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Vascular AccessCannulation and Care

A Nursing Best Practice Guide for Arteriovenous Fistula

Editors

Maria Teresa Parisotto Jitka Pancirova

Vascular Access Cannulation and CareA Nursing Best Practice Guide for Arteriovenous Fistula

This book is an initiative of Maria Teresa Parisotto (Director Nursing Care Management,

NephroCare Coordination, Fresenius Medical Care Deutschland GmbH), Germany and Jitka Pancirova, (EDTNA/ERCA Executive Director), Czech Republic

Authors of this best practice guide are:

Alberto Garcia Iglesias RN, Spain Cristina Miriunis RN, B.Ec., Germany Dr. Francesco Pelliccia RN, MSc, Italy Iain Morris RN, United Kingdom Iris Romach RN, MA, Israel Joao Fazendeiro Matos RN, BSc, MBA (c), Portugal Mihai Preda RN, Dipl.-Ing., Romania Nicola Ward RN, United Kingdom Raffaella Beltrandi RN, Italy Ricardo Peralta RN, BSc, Portugal Theodora Kafkia RN, MSc, PhD (c), Clinical Lecturer, Greece

Contributors to this best practice guide are:

Jean Pierre Van Waeleghem RN, BSN, Belgium

Victor Moscardó RN, Germany

Dr. Frank Laukhuf MD, Nephrologist, Germany

Volker Schoder M.Sc., Dipl. Statistician, Germany

Prof. Dr. Daniele Marcelli MD, MBA, Nephrologist, Epidemiologist, Germany

Dr. Adelheid Gauly PhD, MBA, Germany

Dr. Stefano Stuard MD, PhD, Nephrologist, Germany

Reviewers of this best practice guide are:

Dr. Richard Fluck FRCP, MA (Cantab), MBBS, Nephrologist Immediate past President, British Renal Society, United Kingdom

Dr. Maurizio Gallieni MD, FASN, Nephrologist, Researcher at University of Milan President, the Vascular Access Society, Italy

Dr. Otto Arkossy MD, Nephrologist Board Member of the Hungarian Society of Nephrology, Hungary

Emine Unal RN, Turkey

Natalie Beddows RN, United Kingdom

Marjelka Trkulja RN, EDTNA/ERCA Brand Ambassador, Croatia

All rights are reserved by the author and publisher, including the rights of reprinting, reproduction in any form and translation. No part of this book may be reproduced, stored in a retrieval system or transmitted, in any form or by means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher.

Illustration included in this publication are property of Fresenius Medical Care Deutschland GmbH and cannot be used without prior permission of the owner.

First edition: September 2014

European Dialysis and Transplant Nurses Association/ European Renal Care Association (EDTNA/ERCA)Pilatusstrasse 35, CH 6003 Lucerne, Switzerlandwww.edtnaerca.org

ISBN: 978-84-617-0567-2

D.L.: M-17528-2014

Layout, Binding and Printing: Imprenta Tomás Hermanos Río Manzanares, 42-44 · E28970 Humanes de MadridMadrid - Spainwww.tomashermanos.com

Acknowledgements

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Vascular Access Cannulation and Care A Nursing Best Practice Guide for Arteriovenous Fistula

AcknowledgementsThis book is an initiative of Fresenius Medical Care and EDTNA/ERCA. We warmly thank the authors, the contributors and the reviewers for their collaboration and enthusiasm on this project. The content created is an excellent example of multidisciplinary, international teamwork, developing best practice guide for the most important aspect of the haemodialysis patient’s care.

EditorsMaria Teresa Parisotto, Director Nursing Care Management, NephroCare Coordination, Fresenius Medical Care Deutschland GmbH, Bad Homburg, Germany

Jitka Pancirova, EDTNA/ERCA Executive Director, Prague, Czech Republic

SponsorFresenius Medical Care Deutschland GmbH has kindly supported the development of “Vascular Access Cannulation and Care. A Nursing Best Practice Guide for Arteriovenous Fistula”. This handbook is the result of the project.

Acknowledgements

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Table of Contents

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1. Preface ................................................................................. 17

2. Executive summary .............................................................. 23

3. Introduction ........................................................................... 273.1 Aims for the use of this best practice guide ................... 293.2 Groups likely to benefit from this best practice guide ..... 293.3 Scope of this best practice guide .................................... 30

4. Background ............................................................................ 33

5. Vascular Access for Haemodialysis ....................................... 375.1 VA types .......................................................................... 38

6. Arteriovenous Fistula ............................................................. 416.1 Timing for Arteriovenous Fistula creation ........................ 426.2 Selection of vessels ........................................................ 46

6.2.1 Artery ..................................................................... 466.2.2 Vein ....................................................................... 47

6.3 Location of Arteriovenous Fistula creation ...................... 486.4 Surgical technique of anastomosis creation ................... 496.5 Maturation ....................................................................... 51

6.5.1 Physiology of maturation ....................................... 516.5.2 Timing of maturation .............................................. 52

6.6 Failure of Arteriovenous Fistula maturation .................... 536.6.1 Instrumental monitoring of Arteriovenous Fistula

maturation ............................................................. 54

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Table of Contents

7. Hygiene and infection control ................................................ 577.1 Hand hygiene .................................................................. 587.2 Personal Protective Equipment (PPE) and work uniform .. 60

7.2.1 Gloving .................................................................. 607.2.2 Face protection ..................................................... 617.2.3 Aprons and gowns ................................................ 617.2.4 Uniforms ................................................................ 61

8. Arteriovenous Fistula cannulation .......................................... 638.1 Competencies and responsibilities ................................. 648.2 Preparation and assessment .......................................... 65

8.2.1 Preparation ............................................................ 658.2.2 Assessment ........................................................... 688.2.3 Arteriovenous Fistula preparation ......................... 69

8.3 First cannulation .............................................................. 708.3.1 Procedure .............................................................. 70

8.4 Cannulation techniques .................................................. 758.4.1 Rope ladder ........................................................... 768.4.2 The buttonhole technique ...................................... 798.4.3 Area technique ...................................................... 838.4.4 Trypanophobia (fear of needles) ........................... 86

8.5 Needle removal and Haemostasis .................................. 868.6 Complications related to Arteriovenous Fistula Cannulation .90

8.6.1 Haematoma/infiltration .......................................... 908.6.2 Pseudo-Aneurysm ................................................. 918.6.3 Infections ............................................................... 93

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9. Complications of Arteriovenous Fistula (related to the fistula) .. 979.1 Stenosis .......................................................................... 989.2 Thrombosis ................................................................... 1019.3 Aneurysms .................................................................... 1039.4 Complications caused by the Arteriovenous Fistula .... 105

9.4.1 Cardiac Complications ....................................... 1059.4.2 Steal syndrome .................................................. 106

10. Arteriovenous Fistula monitoring and evaluation .................. 11110.1 Arteriovenous Fistula monitoring ................................ 112

10.1.1 Dynamic venous and arterial pressures evaluation ............................................112

10.1.2 Measurements of blood recirculation ............... 11310.1.3 Dialysis efficiency ............................................. 11410.1.4 Arteriovenous Fistula instrumental evaluation . 113

11. Reporting of Arteriovenous Fistula incidents ....................... 11711.1 What, When and Why to report .................................. 11811.2 Reporting tools ............................................................ 126

11.2.1 Paper charts ...................................................... 12611.2.2 E-charts ............................................................. 127

11.3 Corrective actions........................................................ 12811.4 Follow-up of corrective actions .................................... 129

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Table of Contents

12. Patient education for the care of Arteriovenous Fistula ....... 13112.1 Preservation of vessels prior to Arteriovenous

Fistula creation ........................................................... 13312.2 Arteriovenous Fistula care .......................................... 134

12.2.1 Creation ............................................................. 13412.2.2 Arteriovenous fistula maturation ........................ 135

12.3 Protect the lifeline – things to consider in the patient’s daily life .................................................. 137

12.4 Arteriovenous Fistula complications ........................... 138

13. From empiric evaluation to clinical research evidence ........ 14313.1 Recommendations for best cannulation practice ........ 149

14. Conclusions ......................................................................... 153

15. Appendix .............................................................................. 15715.1 Table of abbreviations ................................................. 15815.2 Bibliography ................................................................ 159

16. Index .................................................................................... 165

Preface

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Finally Revealed: ‘Vascular Access – A long awaited Guide to the Art of Needling’ Vascular access is considered to be both the ‘lifeline’ and the ‘Achilles heel’ of the end-stage renal disease patient. Des-pite progress and best practice recommendations, vascular access remains the weak point of the renal replacement ther-apy chain, generating a significant burden for the patient and the healthcare system. Vascular access morbidity, including maturation failure, dysfunction (requiring repetitive interven-tion, revision, angioplasty), infection or more severe complica-tions (swelling of access limb, steal syndrome, heart failure) is the third most frequent cause of hospitalisation in haemodialy-sis patients.

Despite the technical advances in vascular access surgery, prosthesis development, imaging and monitoring, the autologous arteriovenous fistula (AVF) developed more than fifty years ago by Cimino and Brescia remains the ‘gold standard’ providing best outcomes in both the short and long term. It is recognised worldwide from evidence-based and shared clinical experience that the native AVF has the most cost-effective and cost-utility ratio in terms of vascular access and for these reasons should be considered as the first vascular access option in almost all circumstances.

In addition, an international observational study linking Dialysis Outcomes and Practice Patterns Study (DOPPS) has clearly identified that clinical practices have a major impact on AVF outcomes. This practice pattern has been particularly well established in the domain of vascular access management by showing that team expertise is of paramount importance for improving outcomes when related to vascular access creation, monitoring and cannulation. Very few studies have concentrated on the association between VA cannulation

Preface

19practice and fistula survival in order to provide best practice guidelines for dialysis nurses performing these tasks at the patient’s bedside. With the publication of this book Maria Teresa Parisotto and Jitka Pancirova, under the auspices of the EDTNA/ERCA, have filled this gap by providing a nursing best practice guide for vascular access cannulation and care.

The Art of Needling the vascular access has been summarised in a practical, scientific and easy-to-read manual that all nurses and/or caregivers should read in order to improve their own practice.

The Art of Needling suggests that inserting a needle in an AVF requires not only the acquisition of knowledge, but also craftsmanship by nurses. From a medical and psychological perspective, it is important to note that vascular access cannulation is a recurrent drama that takes place three times per week, involving, as the main actors, the patient and the dialysis nurse, under the casting prescription of a nephrologist in a quite stressful and bloody backstage environment, the haemodialysis unit.

Each performance of the drama consists of three acts with corresponding scenes that are perfectly detailed in this book. Act one, “the preparation”: different scenes start with the psychological preparation and move to preparing the forearm/arm, choosing needles and materials, examining the vascular access, cleansing and disinfecting the arm, and using local anaesthesia if required. Act two, “the cannulation”: deals with inserting needles and has scenes that consist of choosing the correct technique and the appropriate materials, securing needles to ensure absolute safety, setting the blood flow parameters required for dialysis adequacy and checking that this can be achieved and maintained over the entire course of the dialysis session. Act three, “the ‘disconnection”: the scenes

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of blood reinfusion to the patient and removing needles should be perceived as the dénouement of the drama.

In conclusion, this practical, well-documented nursing guide for vascular access cannulation and care will certainly be welcomed by nurses and caregivers in the dialysis field. It fills the gap that existed between the best clinical guidelines and the need to implement best clinical practices in this field on a daily basis. I would like to thank/congratulate all contributors for their excellent work. My hope is that “The Art of Needling” the vascular access, will contribute to improving the daily care of the patient and reduce both the burden and drama associated with vascular access needling for the haemodialysis patient.

Professor Bernard Canaud, Emeritus Professor of Nephrology at the School of Medicine of Montpellier University I, Montpellier, France, and Chairman of the Medical Board at Fresenius Medical Care Deutschland GmbH, Bad Homburg, Germany

Preface

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Executive Summary

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Executive SummaryFor patients with end-stage renal disease (ESRD) undergoing haemodialysis, the arteriovenous fistula (AVF) is quite literally their lifeline. It provides the means by which their blood can be remotely filtered to remove potential toxins and returned to the body. Indeed, the success of long-term haemodialysis depends chiefly upon the patient having trouble-free vascular access (VA) – and the AVF is considered to be the gold standard of VA for dialysis.

It is important that the site of the AVF is chosen carefully. It needs to be easily accessible for the dialysis procedure, whilst also having minimal complications for the patient. As areas that meet both requirements are limited, it is therefore important that the AVF remains patent for as long as possible. While the surgeon clearly plays a vital part in providing a functioning VA, dialysis nurses, other carers and patients themselves also have important roles to play.

Using the correct cannulation technique to gain access for dialysis is crucial for the long-term survival of the AVF. In general, the dialysis nurse is responsible for cannulation and must therefore learn and develop this skill in order to prevent causing patients unnecessary pain and distress, to ensure that the access functions well and to reduce the risk of infection and other morbidities. To date, training materials and best practice guidelines aimed specifically at dialysis nurses have been lacking.

This Guide, which has been developed by an international panel of experts, aims to define AVF cannulation practices based on the most recent available clinical evidence, and to provide recommendations for AVF cannulation and care. It begins by explaining how and why the AVF is created, and the factors that influence the timing of the procedure and where

Executive Summary

25the AVF is located. It highlights the pivotal importance of good hygiene and infection control, including recommendations for personal protective equipment.

The Guide makes detailed recommendations to enable nurses to assess, plan, implement and evaluate the care given to patients before, during and after cannulation of the AVF, and to recognise and deal with complications of the VA. It provides step-by-step guidance for selecting and performing different cannulation techniques, including checklists of the equipment required and recommendations for recording and reporting complications. The need for highly experienced dialysis nurses to train other nurses in the skills they have acquired is also emphasised.

Failure of the VA is a major cause of morbidity, which may result in hospitalisation and/or loss of the access site. Nurses must therefore educate patients on precautions to preserve the AVF, day-to-day care, and how to recognise signs and symptoms of possible complications. Finally, the Guide provides a reminder that the highly invasive and frequent nature of haemodialysis can be a great burden for patients, that they may need help in understanding their diagnosis and treatment, and may need emotional support to deal with the changes it makes in their lives.

The care and management of a VA for haemodialysis is not without its challenges. This Guide is designed to address some of these and to raise awareness of the importance of a healthy and effective AVF. In so doing, the Guide aims to contribute to improvement in the quality of care for patients with ESRD.

Introduction

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3. IntroductionTo a large extent, the success of long-term haemodialysis depends upon the patient having a trouble-free vascular access (VA). VA-related complications remain a serious clinical problem, with VA failure being a major cause of morbidity leading to a high percentage of hospitalisations in the dialysis population.

The Arteriovenous Fistula (AVF) has been in use since it was first created over 40 years ago. The principal cannulator in the dialysis community is traditionally the dialysis nurse; however, there are only a few recommendations, guidelines and educational materials available for dialysis nurses at present in published literature, and almost every dialysis unit has its own technique and procedure.

Currently available guidelines are mainly targeted at physicians and do not describe cannulation techniques.

Haemodialysis therapy requires a VA through which an adequate blood flow can be obtained to ensure the removal of toxins and the return of blood to the patient. The VA, since it is used on a regular basis, should be reliable and easy to use, with minimal risk to the patient. Providing good quality, reliable and safe VA can be difficult to achieve. This is made possible using an AVF or synthetic Arteriovenous Grafts (AVG) made of e.g. polytetrafluoroethylene (PTFE) rather than Central Venous Catheters (CVC). AVF is the preferred VA compared with AVG and CVC due to the relatively longer access life resulting from fewer episodes of thrombosis and infections, fewer hospital admissions, and lower costs. AVF is the gold standard for haemodialysis access, demonstrating improved survival rates and lower complication rates than AVG or CVC. The AVF should be visible, palpable with bruit present, free from signs of infection and should allow adequate dialysis.

Introduction

29The success of the VA can be measured by its capacity to deliver an adequate blood supply (and therefore an acceptable blood flow rate), the survival of the access and the number of complications associated with it. Poor VA can result in increased hospital admissions, inadequate dialysis and complications leading to higher mortality rates.

3.1 Aims for the use of this best practice guide

• To raise awareness of the importance of AVF as the ‘patient’s lifeline’

• To define AVF cannulation practices based on the available clinical evidence and so minimise complications

• To provide recommendations for AVF cannulation and care

• To improve quality of patient care

3.2 Groups likely to benefit from this best practice guide

• Nurses • Physicians • Healthcare assistants • Patients• Payers

Nurses, in particular, play a crucial role in the management of AVF; therefore it is essential to focus on their educational needs and provide guidance in this area.

This best practice guide has been designed to help and support all involved staff on the most appropriate approach

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to manage, preserve and prolong the life of the AVF. Patient education is essential to ensure optimal AVF care.

3.3 Scope of this best practice guideIn scope:

• Arteriovenous Fistula * Responsibilities of the nurse * Assessment of the AVF * Hygiene and infection control * Cannulation techniques * Needle removal and haemostasis * Complications: prevention and detection * Documentation and reporting * Patient education

Out of scope:

• Arteriovenous Grafts (AVG)• Central Venous Catheters (CVC)• Patient self-cannulation

Introduction

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Background

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Vascular access for haemodialysis is closely linked to the history of dialysis. The challenge of repeated VA prevented dialysis from becoming a routine method of treatment.

In 1924 Georg Haas from Germany performed the first haemodialysis treatment in humans. In a 15-minute procedure, he used glass needles to access the radial artery and return blood into the cubital vein.

In 1943 Willem Kolff, from the Netherlands, developed a ‘rotating drum kidney’ with a larger filter surface area made from a cellophane membrane. The first patient he dialysed received 12 dialysis treatments, but the therapy was then stopped due to a lack of access sites, since placing each cannula required a separate incision along the artery.

The outcome changed dramatically in the 1960s, when the idea of connecting an artery and a vein with rubber tubing and a glass cannula, originally considered by Nils Alwall from Sweden, was developed by Quinton, Dillard and Scribner into an external AV Teflon shunt. Their first patient survived for more than 10 years after the insertion of his first Teflon AV shunt in March 1960. The tapered ends of two thin-walled Teflon cannulas were inserted into the radial artery and the adjacent cephalic vein, respectively, in the distal forearm. When not in use for dialysis, the external ends were connected by a curved Teflon bypass tube and later replaced by flexible silicon rubber tubing.

In 1961 when unable to find a surgeon to place the necessary dialysis cannula Stanley Shaldon, used the Seldinger technique to insert catheters into the femoral artery and vein. The native AVF was born in 1966, when Brescia, Cimino, Appel and Hurwich published their landmark account of 14 side-to-side anastomoses between the radial artery and the cephalic

Background

35vein at the wrist. In 1968, Lars Röhl presented results from 30 patients with radial-artery-side to vein-end anastomosis. Then, in 1977, the Gracz fistula was presented and subsequently modified by Klaus Konner. This was a proximal forearm fistula that relied on the perforating vein from the superficial to the deep forearm venous system to limit blood flow in the fistula and prevent occurrence of the steal syndrome in patients with peripheral artery disease due to age, hypertension or diabetes.

In 1969 George Thomas attached Dacron patches to the common femoral artery and vein, which were then connected with a silastic tube and brought to the surface of the anterior thigh. The Thomas shunt was soon replaced by the expanded Polytetrafluorethylene (PTFE) graft when LD Baker presented the first results in 72 haemodialysis patients in 1976. PTFE remains the graft material of choice, even though grafts made of biological materials have been available since 1972.

Vascular Access for Haemodialysis

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5. Vascular Access for Haemodialysis

5.1 Vascular Access TypesThere are three types of VA for haemodialysis, which have different life spans once created:

• Central Venous Catheter can be used directly after insertion (see Figure 1)

• Arteriovenous Grafts can be used for dialysis treatment 2–3 weeks after placement; some of them (early cannulation Grafts) can be assessed for use one day after placement (see Figure 2)

• Arteriovenous Fistula can be used for dialysis treatment between 6–12 weeks after creation and can be assessed for use 4 weeks after creation (see Figure 3)

The choice of VA is dependent on the vascular status and clinical condition of the patient, and the time available before initiation of haemodialysis.

Current guidelines recommend AVF as the gold standard for haemodialysis access, rather than CVC and AVG.

Compared to CVC or AVG, AVF is associated with:

• Longer patency and lower complication rates • Fewer episodes of thrombosis and infections• Optimal dialysis dose• Fewer hospital admissions• Reduced costs

Vascular Access for Haemodialysis

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Figure 1. Central Venous Catheter

Figure 2. Arteriovenous Graft

Figure 3. Arteriovenous Fistula

Arteriovenous Fistula

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6 Arteriovenous Fistula

An AVF is a ‘surgically created opening between an artery anastomosed to a juxtaposition (nearby) vein allowing the high pressure arterial blood to flow into the vein causing enlargement, and wall thickening’.1 This procedure is known as arterialisation or maturation of the vein, which is necessary to provide a vessel with adequate flow for haemodialysis and sufficient strength for effective cannulation. The outflow vessel should either be naturally superficial or surgically superficialised.1

The creation of a well-functioning AVF is not simple to achieve and sometimes requires corrections – even prior to the first use. Therefore, an AVF should be created as early as possible, ideally up to 6 months before it is required.2

6.1 Timing for Arteriovenous Fistula creation

Early referral of patients with Chronic Kidney Disease (CKD) to a nephrologist and/or vascular surgeon is strongly recommen-ded. This approach helps to preserve access sites and pro-vides adequate time for planning the creation and allowing maturation of the vascular access.3

Recommendations based on Glomerular Filtration Rates (GFR):

• GFR <30 mL/min/1.73 m2 – initiate education of the patient and family relating to End Stage Renal Disease (ESRD) management, including the options of transplantation, dialysis alternatives, and dialysis access

• GFR ~20 mL/min/1.73 m2 – initiate access creation and placement (AVF, peritoneal catheter) and initiate work-up for the transplant list


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• GFR ≤10 mL/min/1.73 m2 – initiate dialysis according to nephrologist´s evaluation

Patients with stage 4 CKD or those suffering from a rapidly deteriorating GFR should be referred to a nephrologist for further assessment for Renal Replacement Therapy (RRT). If haemodialysis is the preferred treatment option for these patients, the decision as to which type of VA to use should be made at the same time.

A complete patient evaluation is recommended prior to creation of an AVF (Table 1).3

Table 1. Recommendations for patient evaluation prior to Arteriovenous Fistula creation

Aspects to consider Reason

History of CVC, pacemaker

History of arterial or peripheral catheter (e.g. oncology therapy)

Associated with subclavian vein stenosis

Intravenous cannulation of the arm vessels can cause severe damage and endanger the creation of an AVF

Diabetes Mellitus

People with diabetes are at higher risk of developing Peripheral Vascular Disease (PVD). PVD occurs when atherosclerotic plaques, composed of cholesterol and other fatty substances, found in the blood, build up in the inner linings of the artery walls and hinder blood flow

Anticoagulant therapy or disorders

Complications during the use of the AVF, such as bleeding after therapy and rheological disorders


4444Aspects to consider ReasonCongestive Heart Failure (CHF)

May be exacerbated due the extra blood flow from the AVF

Heart valve replacement

May lead to increased risk of cardiac related infections

Comorbidities that limit life expectancy

The patient might die before the AVF is ready to be used

Previous arm, chest or neck trauma, or surgery

Can harm the blood vessels of the arms

The dominant armThe dominant arm should be avoided, if possible, to minimise the impact on patient’s quality of life

Anticipation of a kidney transplant from a living donor

AVF may not be required as a CVC or Peritoneal Dialysis Catheter may be sufficient for a short time prior to transplantation.

Physical examination and Doppler ultrasound of the arteries and veins of the arms

Assess the condition of the blood vessel system, particularly collateral veins in the extremities

Evaluation of oedema in the arms

Oedema indicates venous outflow problems that may limit the development of an AVF

Compatibility of arm size and presence of scars

Assess if there is sufficient space to cannulate

Trypanophobia (fear of needles)

Can increase the difficulties associated with cannulation. (Patient may be referred to Peritoneal Dialysis)


45Aspects to consider ReasonBody mass index (BMI) score above 35 kg/m2

Careful assessment of the veins in obese patients is required as transposition of the vessel may be necessary

Gender

Differences between genders may in part be due to smaller vessel diameter in women. However, even when routine preoperative vascular mapping is used to select vessels having suitable diameters, an AVF is less likely to mature in women than in men4


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6.2 Selection of vessels6.2.1 ArteryThe main artery of the arm is the brachial artery; this runs from the shoulder to the elbow where it branches into two further arteries – the radial and ulnar – which later sub-divide, result-ing in smaller arteries (see Figure 4). An AVF can be crea-ted along these arteries depending on the individual patient’s cardiovascular system and careful instrumental assessment of their vessels.5,6

Figure 4. Anatomy of blood vessels in the arm


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Arterial requirements for AVF creation include:

• Unobstructed inflow into the planned AVF • Patent palmar arch • Luminal diameter of 2.0 mm or greater at the site of the

planned anastomosis• Ability of the vessel to dilate after AVF creation, which

is sometimes a more important requirement than the diameter of the vessel4

6.2.2 Vein

There are several veins in the arm which can be used, as des-cribed in the text below:

• In the extremity of the arm, there are the radial, ulnar and interosseous veins

• The basilic and cephalic veins, which are superficial, converge to the axillary vein; however, many anatomical variations occur

• Proximally, the axillary vein originates at the lower border of the teres major muscle in continuity with the brachial vein

Venous requirements for AVF creation include:

• Unobstructed outflow from the planned AVF• Luminal diameter of the venous outflow of ≥2.5 mm • A straight segment for cannulation • Vein depth of less than 1 cm from the skin surface• Direct continuity of the outflow vein with the central

veins


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6.3 Location of Arteriovenous Fistula creationSuccessful dialysis treatment starts with good access.5 To achieve a well-functioning AVF, the multidisciplinary team, comprising a nephrologist, vascular surgeon, radiologist and CKD nurse, needs to make a thorough perioperative analysis.

Figure 5. Anatomy of arteries and veins in the arm and points of fistula creation


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Ideally using the non-dominant arm, the AVF should be crea-ted as distally as possible to allow for future AVF creation, if needed (see Figure 5).4 Locations for the creation of AVF in-clude the following:

• AVF at the base of the thumb • Standard/Modified Brescia–Cimino wrist AVF • Forearm cephalic AVF at dorsal branch • Mid-forearm cephalic AVF • Antecubital AVF • Cephalic AVF at the elbow • Transposed basilic AVF

6.4 Surgical technique of anastomosis creationTable 2. The recommended techniques for the creation of the anastomosis6,7

Method Advantages Disadvantages

Artery-side to vein-side anastomosis (see Figure 6)

Technically simpler

Only possible if the artery and vein are in close proximity

It is the most likely AVF to be associated with venous hypertension of the hand. This complication is moderated by the presence of venous valves that prevent reversal of venous blood flow in the hand, at least in the early months


5050Method Advantages Disadvantages

Artery-end to vein-end anastomosis (a system used in the 1970s; due to the associated disadvantages this method is not in use today) (see Figure 7)

AVF flow avoids the development of a hyper-circulatory state

Technically more demanding when there are large differences in the luminal diameters of the artery and vein

Ischaemia of the hand, especially with diabetics and the elderly

If venous thrombosis supervenes, it will extend into the arterial limb of the AVF

Artery-side to vein-end anastomosis (the most commonly used technique and currently the most widely accepted anastomosis variant for AVF creation) (see Figure 8)

The best solution when the artery and the vein are far apart and must be brought closely together

No acute angles

Venous thrombosis will affect only the venous side of the AVF

If the AVF has to be revised, it is easy to create an anastomosis at a more proximal site

Torsion when transporting the venous stump to the artery


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Figure 6. Artery-side to vein-side anastomosis

Figure 7. Artery-end to vein-end anastomosis

Figure 8. Artery-side to vein-end anastomosis

6.5 MaturationA primary AVF should be mature, ready for cannulation with minimal risk for infiltration, and be capable of delivering the prescribed blood flow throughout the dialysis procedure.1

6.5.1 Physiology of maturationBlood flow increases immediately after the creation of the AVF due to vasodilation and vascular remodelling. This can lead to:

• Reduction of mean sheer stress, which returns to normal after 3 months

• Progressive increase in the diameter of the proximal antecubital vein

• No change in the thickness of the intima media • Appearance of eccentric hypertrophy in the venous

side of the AVF • Adaptive remodelling of the vein vessel wall, induced by

reorganisation of cellular and extracellular components • Deformation of the endothelial cells (due to the friction-

al force generated by blood flow acting on the apical cells surface) in the direction of blood flow, since these cells play a central role in adaptive remodelling

• Increased arterial diameter due to elevated flow after creation of an AVF

• Remodelling of the radial artery, without arterial hy-pertrophy, despite a marked increase in diameter and blood flow


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• Research shows that uraemia in CKD patients has only a small influence on the maturation of the AVF6

6.5.2 Timing of maturationThe time to AVF maturation differs from patient to patient. The European Renal Best Practice (ERBP) recommends the minimum maturation period should ideally be at least 4 weeks. Adequate AVF flow (>600 mL/min) and diameter (>5 mm), as measured by ultrasonography can confirm AVF maturation.

In the USA the general opinion is that 8–12 weeks is required to assess the occurrence of complications.

In contrast, in Europe it is considered that any problems or complications will be evident within 4 weeks and it is not necessary to wait for 8–12 weeks. However, the appropriate time to use the AVF depends on its maturation, patient’s individual vein development, alternative access situation, and the cannulation expertise of the staff involved.2,3

The rule of 6s (Assessment for maturation)1,2

• The maturation should be assessed by an expert within 6 weeks of creation

• Flow through the vessel should exceed 600 mL/min• The vessel should be greater than 6 mm in diameter• The vessel should be less than 6 mm beneath the

skin surface

If, after 6 weeks, the veins are not large enough to cannulate, the patient should be referred for re-evaluation (VA surgeon and/or interventional radiologist/nephrologist). There may be collateral veins that can be tied off or a fistulogram may detect stenosis that could be corrected to improve blood flow.2,3


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6.6 Failure of Arteriovenous Fistula maturationEarly failure of AVF maturation occurs up to 3 weeks after creation (Table 3). Evidence shows that 28–53% of new AVF will never mature.8 Access flow greater than 400 mL/min on days 1 and 7 after creation of the AVF is considered the best indicator of the success of AVF maturation. In cases where the access flow is less than 400 mL/min, the underlying reasons should be identified as early as possible.4,7

Table 3. Failure of AVF maturation

Problem Cause Signs and symptoms

Assessment /Treatment

Non-maturing outflow vein

Poor arterial flow

Small vein size

Minimal increase of vein size limited to anastomosis areaAbsence of palpable thrill and bruit by auscultation

Doppler ultrasound or fistulogram to measure flow and detect stenosis

Angioplasty or surgical revision

Disturbances in flow dynamics, usually venous stenosis

Venous hypertension

Carpal tunnel syndrome

Increased venous return

Engorgement of vessels distal to the anastomosisEngorgement of the thumb veinCyanotic vein bedOedema of the handSwelling of the arm, breast, chest and face

Arm elevation above the level of the heart



5454Problem Cause Signs and

symptomsAssessment /Treatment

No arterialisation of the venous side of the AVF

Accessory veins

Juxta-anastomotic stenosis between artery and vein

Occlusion of the main vein will change the thrill in augmented pulse

Closure of the accessory veins by surgery or coil ablation


Infections within 3 weeks of surgery

Perioperative infections

Local and general fever, red skin and/or oedema

Antibiotic therapy

6.6.1 Instrumental monitoring of Arteriovenous Fistula maturation

The gold standard for assessing maturation is the use of instrumental monitoring.

There are a number of instrumental methods available for the monitoring and surveillance of the AVF (Table 4).

Table 4. Instrumental monitoring and surveillance methods2,9

Parameter Method

Pressure surveillance Intra Access Pressure (IAP)Static Venous Pressure (SVP)Dynamic Venous Pressure (DVP)

Recirculation (using a non-urea based dilution method)

Ultrasound Dilution Test (UDT)


55Parameter Method

Flow surveillance Duplex Doppler Ultrasound (DDU) (quantitative colour velocity imaging) Magnetic Resonance Angiography (MRA)Variable Flow Doppler Ultrasound (VFDU)Ultrasound Dilution Transonic (UDT)Crit-line III (optodilution by ultrafiltration; [Hema Metrics] [OABF])Crit-line III direct transcutaneous (Hema Metrics) (TQA)Glucose Pump infusion Technique (GPT)Urea Dilution (UreaD)Differential conductivity (haemodynamic monitor [HDM])In-line Dialysis (DD)

Hygiene and Infection Control

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7 Hygiene and infection control

Healthcare-Associated Infections (HCAIs) relate to infections associated with healthcare delivery and are recognised as a major cause of death worldwide. An effective hygiene and infection control programme/policy is essential, and healthcare staff must be trained appropriately and provided with the necessary resources/equipment to carry out tasks and procedures safely and effectively.

Infection is the second most common cause of fistula loss after stenosis /thrombosis.10

Infection in a AVF can usually be treated with antibiotics, but in some cases a new access may be required.11 The best action is to prevent infection in the first place.

Infection prevention and control is a collective term used for those activities intended to protect people from infections.12

Standard precautions prevent healthcare-associated trans-mission of infectious agents among patients and healthcare workers, and they must be applied to all patients – regardless of their infection status – in all healthcare settings. They are based on the assumption that all blood, body fluids, secre-tions, excretions (except sweat), non-intact skin, and mucous membranes may contain transmissible infectious agents.

7.1 Hand hygiene

The hands of Healthcare Workers (HCW) play a major role in the transmission of HCAIs.

In accordance with the World Health Organization’s (WHO) goals, this best practice guide pursues the following prevention targets:


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• Colonisation with possible resulting exogenous infection of patients

• Endogenous and exogenous infection in patients• Infection in HCW• Colonisation of the healthcare environment and HCWs

The Five Moments of Hand Hygiene Concept

World Health Organisation (WHO)13 defines five moments of hand hygiene. They correspond to the concept of patient area, healthcare zone and critical sites, and are applicable to all care activities in the clinic:

1. Before touching a patient2. Before clean/aseptic procedure3. After body fluid exposure risk4. After touching a patient5. After touching patient surroundings

In accordance with the WHO consensus recommendations, hand hygiene should routinely be performed by cleansing with alcohol-based hand rub.

There are indications when hands must be washed with soap and water

Each HCW must be trained on when to use which methods of hand hygiene and how to carry out the respective techniques.

To ensure that hand rubbing or hand washing is carried out effectively, it must be ensured that alcohol-based rub or water and soap, respectively, covers the entire surface of the hands and wrists.


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Rings, wristwatches and bracelets must not be worn when carrying out direct patient care activities. The only exception to this is a single plain wedding band, which must be manipulated during the hand hygiene process to ensure the skin underneath is effectively cleaned and dried.

Hand hygiene and keeping the AVF clean are the most important actions in relation to infection control.

7.2 Personal Protective Equipment (PPE) and work uniform

PPE (hand and face protection, aprons and gowns) serves to protect HCW from hazards and preventable injuries in the workplace. Some PPE items, such as gloves and masks, protect HCWs and patients

• It must be ensured that PPE does not pose a hazard to others, e,g. PPE must be changed between patients

• PPE must be removed and discarded or disinfected after use

• Hand hygiene must be performed after the removal of PPE

7.2.1 Gloving

The wearing of medical gloves in a healthcare facility serves a dual purpose:

• Gloves protect the HCW from the exposure to blood and other body fluids

• Gloves reduce the spread of microorganisms from the HCWs’ hands to the environment, the transmission between HCWs and patients, and the transmission from one patient to another


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7.2.2 Face protectionThe mucous membranes of the eyes, nose, and mouth need special protection during patient care activities that are likely to generate splashes or sprays of blood, body fluids, secretions or excretions. Mucous membranes are penetrated more easily by pathogenic organisms than intact skin. Therefore, a face shield or goggles must be worn during connection and disconnection of AVF.

7.2.3 Aprons and gownsAprons and gowns are part of the PPE that is worn to comply with standard precautions14 or contact precautions (to prevent transmission of infectious agents that are spread by direct or indirect contact with the patient or the patient’s environment, and for which transmission cannot be interrupted by standard precautions alone).

7.2.4 UniformsUniforms are not considered as PPE. They do not protect against fluids because the cloth (usually cotton) is permeable. They do, however, serve a dual purpose. They provide the HCW with professional attire that supports the HCW in carrying out her or his work in the dialysis unit, while at the same time preventing cross-contamination between the workplace and the home. They also convey a professional image to the patient.

Do not perform any activities without appropriate hand hygiene. Always wear personal protective equipment

Arteriovenous Fistula Cannulation

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8 Arteriovenous Fistula cannulationThe goal should be to cannulate all AVFs safely without causing damage to the patient’s lifeline. It must be ensured that all dialysis staff members understand and master the basics of AVF. The fundamental principles of VA should be used to help train all dialysis staff members in order to improve the quality of care that dialysis patients will receive. There is a need for nurses to continue to gain knowledge through nursing research and education.15

Proper cannulation is a fundamental aspect of maintaining a functioning AVF

8.1 Competencies and responsibilities AVF is a complex chapter in dialysis care. Prolonging the life and patency of the AVF are important objectives. Therefore a highly-skilled dialysis nurse is required to ensure that each cannulation procedure is carried out with minimal or no complications.

At every dialysis session, and before each cannulation, ensure that the patient’s AVF is functional and has no problems in order to obtain the optimal blood flow ensuring an adequate dialysis.

The competencies and responsibilities to achieve this are as follows:

Nurse• Competence in assessing the AVF • Competence in cannulation techniques and care• Competence in managing of AVF complications • Competence in patient education related to AVF


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• Responsibility for ensuring patient comfort and safety• Responsibility for reporting and documenting all

complications relating to AVF • Responsibility for liaising with the dialysis medical

team to early identify and manage complications

Physician• Responsibility for providing an optimal prescription for

the preservation of the AVF• Responsibility for the effective management of com-

plications

8.2 Preparation and assessment

The procedures take place in the haemodialysis treatment room, ensuring the optimal conditions for procedures under the supervision of a Registered Nurse (RN). Evaluating the patient before haemodialysis treatment will assist the nurse identifying potential problems that may arise during the treatment. Attentively listen to the patient to detect any changes that could be relevant.

8.2.1 Preparation Environment

• The room needs to be clean, windows closed, chair/bed and dialysis machine in the correct position

• Every haemodialysis room/section must have an adequate number of * Sinks with running water, hand soap dispensers, and disposable towels

* Disinfectant dispensers


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• The surface area and equipment used for the procedure preparation must be cleaned and disinfected before and after each use

• The required materials should be placed on the disinfected surface area

• Adequate illumination should be provided during the cannulation procedure

Equipment• Stethoscope

Materials• Skin disinfectant • Drape• Gloves • Sterile dressing pack (gauzes)• Tape• Syringes (e.g. flushing fistula needles or blood

samples, if required)• Tube for blood sample, if required• Needle (for sterile 0.9% saline solution, if required)• Tourniquet • Fistula needles (see table 5)• Waste bin• Sharps container• Medication e.g. anticoagulants according to physician’s

prescription

It is recommended that complete, pre-defined kits for connection and disconnection procedures are always available


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Table 5 Recommended needle gauge according to blood flow rate aimed

Blood flow rate Recommended needle gauge<300 mL/min 17 gauge300–350 mL/min 16 gauge350–450 mL/min 15 gauge>450 mL/min 14 gauge

Nurse• Wash and dry hands according to WHO recommenda-

tions and wear PPE (refer to chapter 7.2)• Place the materials required on the disinfected surface• Ensure that the patient is relaxed and sitting comfortably • Explain all routine and non-routine procedures or

activities to the patient as required

Patient • Wear comfortable clothes (remove jewellery if present) • Wash the access arm with water and soap (see Figure

9). If not able to wash the access arm, the nurse should provide assistance

• Ensure AVF is easily accessible

Figure 9. Patient washing AVF arm


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8.2.2 AssessmentA physical assessment must be carried out before every cannulation regardless of when the AVF was created.In the case of being unfamiliar with the patient’s AVF, seek advice from an experienced senior nurse and check the patient’s clinical file.AVF physical examination is important to evaluate the proper function and to detect possible signs of complications (as indicated in Table 6).

Table 6. Clinical monitoring of Arteriovenous Fistula

Action Possible signs

Look – inspection8

(see Figure 10)

Oedema, redness, swelling, bruising, haematoma, rash or break in skin, bleeding, other exudate, aneurysm or pseudo-aneurysm

Feel – palpation (see Figure 11)

Character of pulse, change in temperature, atypical warmth, tendernessDirection of the flow, flow characteristics along the fistula (thrill versus pulse)N.B. The thrill should feel like a continuous vibration, not a strong pulsation

Listen to the fistula – auscultation (see Figure 12)

Auscultation for bruit along the vein for the quality of the sound and its amplitude N.B. The bruit – a whooshing sound – should be strong and continuous; each sound linked to the one before

In case of absence of bruit and/or thrill, DO NOT cannulate the AVF!


69Figure 10. Look – inspection Figure 11. Feel – palpation Figure 12. Listen – auscultation

Document every assessment and report any abnormalities to the senior nurse and/or physician

8.2.3 Arteriovenous Fistula preparationProper needle-site preparation by both the patient and staff reduces infection rates. Site selection should be done prior to the final skin preparation.

Prepare the patient’s skin.

• Clean and disinfect the patient´s skin with an appro-priate solution

• Disinfect AVF site before needle insertion for approxi-mately 30–60 seconds. Allow to air dry for 30–60 sec-onds. Follow manufactures instructions for contact time

• Start at the chosen cannulation site and move out-wards in a circular rubbing motion that will carry bac-teria away from the selected needle insertion site (see Figure 13)

• Repeat skin preparation if the site is touched by the patient or staff once skin preparation has been applied but the cannulation is not completed


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• If using the buttonhole cannulation technique, disinfect before and after scab removal

Figure 13. Skin preparation before cannulation

8.3 First cannulationA newly created primary AVF will be allowed to develop for at least 4 weeks prior to cannulation. Initial attempts to perform dialysis via the new fistula should be performed cautiously.

8.3.1 ProcedureFor a successful cannulation of a new AVF, the following steps are required:

• Obtain approval from a physician to start cannulation of the AVF

• Explain the procedure to the patient. Help the patient to overcome any fear of the initial cannulation

• Experienced, qualified staff should carry out new AVF cannulations

• Use a tourniquet or some form of vessel-engorgement technique (e.g. ask the patient or a staff member to compress the arm)

• Use 16G or 17G needles initially (see Figure 14)• Always stay at least 4–5 cm away from the anastomosis


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• When CVC is still present and AVF not fully developed, use one CVC lumen and a 16G–17G needle for the arterial or venous site, according to the physician’s prescription, (see Figure 15)

Only nurses identified as competent in best cannulation practice techniques should be assigned to

cannulate newly developed AVF

Figure 14. First cannulation with two needles

Figure 15. First cannulation with one needle and CVC

• The venous needle must always be placed in the direction of the blood flow. In contrast, the arterial needle may point in either direction:


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* Antegrade – arterial needle pointing in the direction of blood flow

* Retrograde – arterial needle pointing against the direction of blood flow

• Secure and support the access using one of the fo-llowing: * The ‘three-point’ technique (see Figure 16):

- Stabilise the access with the thumb and forefinger - Pull the skin taut towards the cannulator - Compress the dermis and epidermis. This allows easier cannulation and temporary interruption of pain

Figure 16. The ‘three point’ technique

• The ‘L’ technique * Hold thumb and index finger as an ‘L’ * The thumb should hold the skin taut over the AVF, and the index finger should stabilise and help engorge the AVF (see Figure 17)


73Figure 17. The ‘L’ technique

• Insert the needle * Use an approximately 20–35º angle of insertion depending on the depth of the access (The insertion angle is measured from the skin to the needle hub. The needle enters the skin and tissue above the AVF vessel first, and then the vessel itself) - A less steep angle increases the risk of dragging the cutting edge of the needle along the surface of the vessel

- Steeper angles increase the risk of perforating the underside (back) of the vessel

• Advance the needle * Once the AVF vessel is entered, the blood flashback is visible in the needle tubing. Advance the needle slowly with very minimal pressure and with the cutting edge facing the top of the vessel

* Do not ‘flip’ or rotate the bevel of the needle 180°. Flipping can lead to stretching of the needle-insertion site, can cause oozing during dialysis treatment and can damage the intima of the vessel


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• To prevent side wall infiltration, advise the patient not to move the arm with AVF during cannulation/treatment

• Rotation of the needle must be avoided

• Avoid prolonged needle adjustment

• In the case where additional cannulation attempts are necessary, remove the first needle if possible, correctly disposing of it; then insert a new needle

• Tape the needle in place * Tape the needle at an angle similar to that of insertion * To avoid the needle tip from moving DO NOT press the needle shaft flat against the skin as this can cause damage to the intima of the vessel

* Secure the needle using a minimum of three strips of tape: one to fix the wings, a second on top of it to secure the needle and a third one to secure the needle tubing (see Figure 18)

Figure 18. Needle taping


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8.4 Cannulation techniquesThe most important procedure is the cannulation of an AVF and over the course of a day it is carried out on numerous oc-casions by the dialysis nurse. Choice of the correct cannula-tion site and technique are fundamental factors for an optimal dialysis session, and for a satisfied and comfortable patient.

Cannulation of the AVF must be performed by using one of these techniques:

• Rope ladder• Buttonhole• Area

The ideal technique has not yet been established, although area is the least favoured.

Do not cannulate in the area of an aneurysm

It is recommended that:

• Arterial needle is cannulated first

• Access is kept visible at all times

• Same sites are not re-cannulated within two weeks (expect buttonhole)

• New sites are at least 3 mm. away from previous sites, unless otherwise specified in the patient treatment plan (e.g. buttonhole)

• Needle tips are placed at least 5 cm apart from each other, if possible


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8.4.1 Rope ladderThe rope ladder is also known as site-rotation technique.

• For each cannulation, a new site is selected ~5 mm away from the previous one. Cannulation sites are rotated along the length of the AVF (see Figure 19)

Advantages• Reduced risk of aneurysm formation• Allows healing of previous cannulation sites• Low risk for infection

Disadvantages• Pain during cannulation • Scarring of the vessel• Risk of losing AVF due to poor technique application

Figure 19. The rope ladder technique

An example of best practice for rope ladder technique rotation: Arterial (A) to Venous (V): A1 to V1; A2 to V2; A3 to V3; A4 to V4; A5 to V5


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Before cannulation

• Prepare environment (refer to Chapter 8.2)• Prepare materials (refer to Chapter 8.2)• Attend to hygiene requirements (refer to Chapter 7)• Prepare the patient (refer to Chapter 8.2)• Assess the AVF (refer to Chapter 8.2)

Technique

• Use a tourniquet or some form of vessel engorgement technique (e.g. ask the patient or a staff member to compress the arm)

• Use either the ‘three-point’ or ‘L’ technique to stabilise the vessel (see Figures 16 and 17)

• Locate the arterial side of the AVF and the direction of the flow. It is recommended that the arterial needle be placed in the direction of the blood flow (antegrade) and bevel down. In case of anatomical restrictions, place the needle against blood flow (retrograde) and bevel up (see Figure 20)

• Locate the venous site of AVF and the direction of blood flow. The venous needle is always placed in the direction of the blood flow towards the heart

• Insert the needles at an angle of 20–35°. When flashback is observed, lower the needle and advance into the centre of the vessel

• Confirm adequate flow with a syringe, if required• Continue with the procedure of connecting to the

extracorporeal blood circuit• Sites on the AVF which display evidence of aneurysm

formation should be avoided


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Figure 20. Needle direction and bevel orientation

Troubleshooting for rope ladder• It is very common for needle tearing to occur, and

this frequently happens at the start of AVF use due to poor cannulation technique. In extreme cases it is manifested in: * A thickened area * Haematoma * Discolouration of the area in the days following the creation

• Angle of entry: * Too shallow can lead to upper wall damage and possible infiltration

* Too steep can lead to back wall damage and possible infiltration

• If resistance is experienced at any time during needle advancement or when changing the position of the

1. arterial needle antegrade bevel up

3. arterial needle antegrade bevel down

2. arterial needle retrograde bevel up

4. arterial needle retrograde bevel down


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needle, it should be withdrawn and redirected at a different angle

8.4.2 The buttonhole technique• The buttonhole technique is a cannulation method

where the AVF is cannulated in the exact same spot, at the same angle and depth of penetration every time

• By using the exact same spot a scar tissue tunnel track will be created

• It is strongly recommended that the procedure is performed by the same cannulator until the track tunnel has been created

• Using a sharp needle it takes approximately 6–12 cannulations (depending on the individual patient) to create a track at a given site

• The creation of a scar tissue tunnel track allows the use of a blunt needle

• The original Buttonhole technique was developed with 2 tunnel tracks (see Figure 21a), where both the arterial and venous sites were cannulated in the exact same spot at each dialysis. In recent times there has been a trend to create more than 2 tunnel tracks and in some cases up to 4 (see Figure 21b), to rotate them thus reducing the risks of complications and prolonging the lifespan of the tunnel tracks

21a

Figure 21. Buttonhole technique

21b


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Advantages• Prolongs AVF life• Reduces pain and bleeding• Reduces missed cannulations • Eliminates risk of infiltrations • Promotes self-cannulation• Decreases hospitalisations related to AVF

complications• Reduces risk of needle stick injury• Reduces risk of aneurysm formation

Disadvantages• Mainly suitable for AVF • Increases the risk of infection• Requires the same highly skilled and experienced

cannulator until the track has been created, unless a tool to guide cannulation is used

• Risk of losing AVF due to poor technique application• Difficult to perform with AVF covered by:

* Heavily scarred skin * Large/small amount of subcutaneous tissue

Before cannulation

• Prepare environment (refer to Chapter 8.2)• Prepare materials (refer to Chapter 8.2)• Attend to hygiene requirements (refer to Chapter 7)• Prepare the patient (refer to Chapter 8.2)• Assess the AVF (refer to Chapter 8.2)• Removal of scab


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• Disinfect the cannulation sites before and after scab removal

Dos and Don’ts for removing scabsDos

• Use sterile tweezers/scab picker to remove scabs• Soak two gauzes/swabs with saline or alcohol-

based solution• Stretch the skin around the scab in opposite

directions

Don’ts• Remove the scab with the needle that will be used

for cannulation – this contaminates the needle• Use a needle to remove the scab; patient’s skin can

be injured• Let patients remove their own scabs• Cannulate unless the scabs are completely

removed• Use the buttonhole track if bleeding occurs when

removing the scabs (use a sharp needle to access the AVF at a new site for this treatment)

Technique• Use a tourniquet or some form of vessel-engorgement

technique (e.g. patient or a staff member to compress the arm). Use either the three-point or ‘L’ technique to stabilise the vessel (see Figures 16 and 17)


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For cannulation until the tunnel track has been created: • Select the insertion sites:

* Whether the AVF has been cannulated previously, or whether this is a first cannulation, carefully choose a straight section without aneurysms and with a minimum of 5 cm between the needles’ tips

• When the tunnel track has been established (a round hole should be visible), cannulation can be performed by any trained nurse and it is recommended to use blunt needles

• Insert the needles at an angle of 20–35° (remember always to keep the same angle, direction and bevel orientation in subsequent cannulations). When flashback is observed, lower the needle and advance it into the centre of the vessel making a note of the depth. The use of excessive force to cannulate the vessel should be avoided

• Confirm adequate flow with a syringe, if required• Continue with the procedure of connecting to the

extracorporeal blood circuit

Troubleshooting for buttonhole• Bleeding can occur around the needle during dialysis if:

* Sharp needles are used and cut the tunnel track * The track is stretched because of trying to direct the needle instead of following the track

* A new tunnel track has torn tissue• If the prescribed blood flow is not achieved, check:

* The needle direction (was it changed compared to previous cannulations?)

* The needle position (is it too shallow or too steep?) * The needle fixation (Is it taped too tightly?)


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• Difficulties with blunt needle insertion can occur when oedema around the insertion sites is present. This leads to problem in following the tunnel track.

• Tap up and down the vessel, trying to find the tunnel track, or switch to a sharp needle for this treatment (being careful not to cut the tunnel track)

• If a tunnel track is not progressing it is acceptable to abandon it and find a new one

If the patient is admitted to another unit, and the nurses do not know how to cannulate using

buttonhole technique, they should move to new sites as long as they stay at a minimum of 2 cm away

from the buttonhole tunnel tracks

8.4.3 Area techniqueThis technique involves repeated cannulations concentrated over a small vessel area (2–3 cm) (see Figure 22). However, repeated cannulations damage the elasticity of the vascular wall and skin, leading to the formation of aneurysms with a tendency for stenotic folding at the border of the aneurysm,11 leading to the appearance of narrowed areas post-aneurysm and increased bleeding time.

This cannulation technique should be avoided and alternative techniques should be explored.

Advantages• Ease of cannulation• Less painful for the patient


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Disadvantages• Damages the elasticity of the vascular wall and skin• Promotes the formation of aneurysms/pseudo-aneu-

rysms and stenosis post-aneurysm• Increases bleeding time• Negative impact on body image

Figure 22. Area technique

Before cannulation

• Prepare environment (refer to Chapter 8.2)• Prepare materials (refer to Chapter 8.2)• Attend to hygiene requirements (refer to Chapter 7)• Prepare the patient (refer to Chapter 8.2)• Assess the AVF (refer to Chapter 8.2)

Technique

• Use a tourniquet or some form of vessel-engorgement technique (e.g. ask the patient or a staff member to compress the arm)


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• Use either the ‘three-point’ or ‘L’ technique to stabilise the vessel (see Figures 16 and 17)

• Locate the arterial side of the vascular access and the direction of the flow. It is recommended to place the arterial needle in the direction of the blood flow (antegrade). In case of anatomical restrictions, place the needle against the direction of blood flow (retrograde)

• Tape the needle as recommended (refer to Chapter 9.3)• Locate the venous site of vascular access and the

direction of blood flow. The venous needle is always placed in the direction of blood flow towards the heart

• Insert the needles at an angle of 20–35°. When flashback is observed, lower the needle and advance into the centre of the vessel

• Tape the needle as recommended (refer to Chapter 9.3)• Confirm adequate flow with a syringe, if required• Continue with the procedure of connecting to the ex-

tracorporeal blood circuit

Troubleshooting for the Area technique• It is very common for needle tearing to occur and more

often this happens at the start of AVF use, due to poor cannulation technique. In extreme cases it is mani-fested in: * A thickened area * Haematoma

• Angle of entry: * Too shallow can lead to upper wall damage and possible infiltration

* Too steep can lead to back wall damage and possible infiltration


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• Difficulties can be experienced with successive cannu-lations due to formation of an extravascular clot result-ing in a haematoma, which can obstruct the needle. In these instances it is recommended that the insertion of the needle is repeated at a new site

• If resistance is experienced at any time during needle advancement, or when changing the position of the needle, it should be withdrawn and redirected at a different angle

• Difficulties can be experienced with successive cannu-lations of the same site due to formation of an extravas-cular clot resulting in a haematoma, which can obstruct the needle. In these instances it is recommended to repeat the insertion of the new needle at a new site

8.4.4 Trypanophobia (fear of needles)

• Staff and patient interactions can help relax and calm the patient. Patient–nurse communication is a powerful tool to use in all cannulation procedures

• Avoid using the words ‘stick’ or ‘needling’; instead use terms like ‘cannulate’, ‘insert’ or ‘place’ when discussing the positioning of the fistula needle into the AVF

• Words alone can cause or reduce fear• Choose the words wisely!

8.5 Needle removal and haemostasis• The procedure of needle removal by the nurse is

as important as the cannulation of the AVF. Needle withdrawal must be done carefully in order to prevent tearing of the vessel, to minimise access trauma and to achieve optimal haemostasis


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• Haemostasis of the first cannulation must always be performed by skilled nursing staff, since the vessel wall is fragile and there is an increased risk of haematoma formation

Procedure• Prepare materials (refer to Chapter 8.2)• Assist the patient to put on a glove so that he/she can

apply pressure on the access site (if able to do so after an appropriate training)

• Stabilise the needle and carefully remove any tape to prevent excessive manipulation leading to possible damage to the access wall and enlargement of the cannulation site

• Remove the tape carefully. Some patients may have very dry skin and care should be taken not to damage it

• Each needle should be withdrawn slowly, keeping the same angle as that of insertion, until the entire needle has been removed. Digital pressure should be applied only after the needle is completely removed to prevent damage to the vessel wall

• The venous needle should be removed first; except if the position of the needle poses risk of protruding arterial needle tip through the access when pressure is applied (pressure on the venous site has a tourniquet effect on arterial needle. If the arterial needle has already been removed, the pressure may cause a haematoma or re-bleed at the arterial site)

• To avoid bruising, compression is essential for good haemostasis. One finger should be positioned over the external insertion site (skin) and the second over the internal insertion site (vessel entry). Pressure should be sufficient to stop bleeding but not so great as to stop the flow of blood through the vascular access.


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Compression that restricts the flow (see Figure 23) of blood through the access may cause the access to clot

Figure 23. Haemostasis pressure An example of best practice for haemostasis is the use of a glove and compression with two fingers, which does not restrict the blood flow through the vascular access

• Thrill should be felt above and below the site of pressure. If the thrill is absent, the pressure on the access should be reduced until it is palpable. The presence of a thrill above and below the pressure sites ensures that the compression does not restrict the blood flow through the vascular access

• The time to haemostasis varies between patients; however, it is usually around 8–12 minutes. Checking for haemostasis early will break the forming clot and re-start bleeding. The haemostasis process is com-pleted when there are no signs of bleeding after re-leasing the pressure

• If it is the first cannulation (or until the vessel is fully developed), maintain the compression for up to 20 mi-nutes to avoid bruising or bleeding that may otherwise complicate the proper development of the AVF. In pa-tients where time to haemostasis is long, an assess-ment of the anticoagulation and of a possible venous stenosis should be considered. In the meantime, cellu-lose haemostatic dressings can be used


89

• Repeat the same procedure for the second needle• Apply haemostatic plaster or tape sterile gauze over

the site. Do not wrap tape completely around the arm. Check for pulse above and below the dressing. Ca-nnulation site is protected from bacterial contamina-tion until a protective scab is formed. Wrapping tape around arm can create a tourniquet effect, restricting blood flow. Remove patient glove (if patient was hold-ing sites)

• Always discharge the patient from the unit with an adhesive dressing or a gauze pad placed over the sites of cannulation

The 10 ‘dos’ of needle removal• Assist the patient in gloving if he or she is able to

hold pressure on the access site • Start with the venous needle• Stabilise the needle and carefully remove any tape• Remove the needle at the same angle as the

insertion angle• Apply pressure by using two fingers, only after the

needle is completely removed• Apply appropriate pressure, thrill should be felt

above and below the site of pressure• Hold for 8–12 min without checking• Hold for up to 20 minutes without checking for the

first cannulation• Apply haemostatic plaster or adhesive dressing to

the site, or tape sterile gauze over the site• Avoid wrapping tape around the arm


9090

The use of venepuncture clamps or special tourniquets for haemostasis of the cannulation sites increases

the risk of complications

8.6 Complications related to Arteriovenous Fistula cannulation

8.6.1 Infiltration/haematomaDefinitionHaematoma is a localized swelling that is filled with blood caused by a break in the wall of a blood vessel. In haemodi-alysis access, it is usually caused by blood leaking from the arterialised vein to the surrounding tissues (see Figure 24).

AetiologyHaematoma results from needle infiltration. Needle infiltration of new AVF is a relatively frequent complication, which occurs most commonly in older patients.

If the access has been assessed as being mature the causes of infiltration/haematoma may be poor cannulation skills, needle manipulation and patient moving access arm during dialysis.

Signs and symptomsCommon signs of infiltration are immediate sharp pain, swell-ing, or surrounding skin discoloration. Signs of haematoma are bruising to the skin and/or hardened lumps; colour chang-es from that of a blue/purple to a yellow/brown as the bruising haematoma resolves.

ManagementInitially, the application of ice (never in direct contact with the patient’s skin) may reduce the haematoma development. If that fails, some antithrombotic ointment could be applied. In some cases, the haematoma may require surgical correction and the use of antibiotics to prevent infection.


91

Figure 24. AVF haematoma

Infiltration of a new AVF is a relatively frequent complication, especially in older patients,

possibly because the vessels are more fragileIt is recommended to use a new cannulation

site avoiding the haematomaHaemostasis techniques are particularly important

after needle withdrawal

8.6.2 Pseudo-Aneurysm

DefinitionA pseudo-aneurysm (false aneurysm (see Figure 25)) is a local disruption of the vessel wall caused by a leakage of blood from an access vessel or Graft into the surrounding tissue with a continuing communication between the originating vessel and the resultant adjacent cavity.

AetiologyThey usually result from repeated cannulation at the same site (area technique). Aneurysms and pseudo-aneurysms are at


9292

risk of complications including rupture with bleeding, infection, and erosion of the overlying skin. Rupture may be a fatal event.

Signs and symptomsPseudo-aneurysms usually present as a painful, tender, pulsatile mass. The overlying skin is sometimes erythematous. Any of the above changes in the overlying skin require urgent evaluation to prevent rupture.

ManagementSome pseudo-aneurysms resolve themselves, while others require treatment to prevent haemorrhage, uncontrolled leakage or other complications. The diagnosis should be confirmed using ultrasound, which will reveal arterial blood flow into the pseudo-aneurysm. A conventional angiogram can also diagnose a pseudo-aneurysm.Many options exist for the treatment of pseudo-aneurysms. While surgery was the gold standard treatment in the past, several less invasive treatment options are popular today like covered stent, ultrasound probe compression, ultrasound-guided thrombin injection and surgical ligation (with or without distal bypass).

Figure 25. AVF Aneurysm/Pseudo-aneurysm


93

Cannulation in the exact area of an aneurysm and pseudo-aneurysm must be avoided

Pseudo-aneurysms can be prevented by using either rope ladder or buttonhole technique

8.6.3 InfectionsOverall, infections account for approximately 20% of VA loss with VA being the source for the majority of cases of bacterae-mia events in haemodialysis patients. Staphylococcus aureus and Staphylococcus epidermidis are the predominant patho-gens.14,15 Bacteraemia frequently occurs during cannulation without infection of the AVF.

Risk factors for AVF infection include pseudo-aneurysms, haematoma, severe pruritus and scratching over needle sites. Furthermore, the use of AVF as an intravenous route for drug abuse and use of the AVF for intravenous medication admi-nistration during surgical procedures.17,18,19 Infection of the AVF may be either superficial or deep. Superficial infections do not involve the fistula itself and are generally related to the ca-nnulation site. On physical examination, superficial infections appear as small lesions (e.g. small white spots on the skin) with minimal or no inflammation, swelling or pain and are not purulent.

The buttonhole technique has been associated with a high risk of infection in some studies:39-41 rates of bacteraemia ranging from 0.15–0.6 per 1000 patient-days, or 0.05–0.2 per patient-year, have been reported.

DefinitionAn infection is the result of an invasion of the body by pathogens and of the effects of their presence in the tissues. Infections

9494

of established AVF are uncommon, are mainly localised to the immediate area, do not progress to bacteraemia and, usually, are caused by staphylococci.20,21 The US Renal Data System (USRDS) reports AVF sepsis rates of 0.52 per patient-year: this compares with a rate of 2.32 per patient-year in patients with CVC (USRDS 2008).

AetiologyInfection is mainly due to the patient’s poor hygiene or poor aseptic technique during cannulation. It can also be caused by contamination of the post-surgical peri-anastomosis haematoma or lymphocele.21,22

Signs and symptomsClinical signs of VA infection are localised redness, tenderness, warmth, oedema, extravasation of local serous or purulent fluid, and increased body temperature. Even in the absence of these clinical signs, infection may be present especially if the patient presents with unexpected sepsis or increased inflammatory parameters.20,23,24,25

ManagementAn AVF infection is a serious clinical problem and should be treated for at least two weeks using appropriate antibiotics. Positive skin and blood culture tests mean that cannulation at the infected site must be avoided and the arm rested.26 In cases of septic embolism during haemodialysis, a surgical excision of the fistula may be performed.4,22,23,27,28 If AVF infections are suspected or diagnosed frequently in a haemodialysis unit, a re-evaluation of the unit’s hand hygiene protocol should be initiated.26 Reports from Canada have demonstrated, in



95

patients using buttonhole technique, the efficacy of topical mupirocin prophylaxis in reducing the risk of patients on home care developing S. aureus bacteraemia.29

If signs and symptoms of infections are observed, refer to a physician for further prescription

Complications Related to Arteriovenous Fistula

97

97


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9 Complications related to Arteriovenous Fistula

9.1 StenosisDefinitionThe lumen of blood vessels that form the AVF can become constricted or narrowed by the proliferation or thickening of their inner layer (see Figure 26). This process is called AVF stenosis.30

AVF stenosis can occur anywhere along the vessel track; it may develop at the inflow (arterial side), middle part and outflow (venous side) of the AVF.20,30,31 Irrespective of where it occurs, stenosis increases the chances of AVF failure.

AetiologyStenosis can occur early in the process, by surgical manipulation during AVF creation and can be related to stretching, torsion or other types of intraoperative trauma.30 The main late causes of stenosis include turbulence, formation of pseudo-aneurysms and poor cannulation technique. Irrespective of the timing, AVF stenosis is caused by intimal and fibrous hyperplasia.27

Figure 26. AVF stenosis

The vessel of the AVF can become stenotic over time as the lumen of the blood vessel becomes constricted or narrowed by the thickening of the inner lining of the vessel.


99

Signs and symptoms

The clinical manifestations differ according to the location of the stenosis.

Stenosis located at the arterial side will induce a low blood flow through the AVF, causing difficulties in cannulation and abnormal changes in the negative arterial pressures (e.g. using a 15-gauge needle and blood pump speed up to 350 mL/min). This type of stenosis can be observed in very early stages of cannulation, or even during maturation.32

Stenosis located in the middle part of the AVF may develop at a later stage and may be caused by poor cannulation technique, trauma or following an infection at the access site. In such cases the part of the AVF between the anastomosis and the stenosis will have a strong bruit and thrill, whilst above the stenosis it may have no bruit or thrill at all. Arterial and venous pressures during dialysis may be normal if the arterial needle is placed below, and the venous needle is placed above the stenosis.32

Stenosis located at the venous side of the AVF will develop a very strong pulsating flow through the access. During dialysis, low negative arterial pressures (e.g. –80 mmHg, using a 15-gauge needle and blood pump speed up to 350 mL/min) and high positive venous pressures are observed (e.g +300 mmHg, using a 15-gauge needle and blood pump speed up to 350 mL/min). Venous stenosis may also be induced after a localised infection or needle trauma with haematoma formation or intimal hyperplasia.

Previous insertion of CVCs may have caused a stenosis at the subclavian vein resulting in a high resistance at the venous side of the AVF.32


100100

Stenosis located at the arterial and venous side of the AVF are characterised by a decreased dialysis dose, with the

most common factors responsible being reduced access flow and a high blood recirculation

Severe stenosis is associated with difficulties in cannulation, a painful arm, oedema and, particularly, prolonged bleeding time following needle removal.

In a juxta-anastomotic stenosis, a water-hammer pulse may be present. Instead of being continuous, the thrill is present only in the systole. As one feels the AVF along its full length, the pulse goes away abruptly when the site of stenosis is encountered. Above the stenosis the pulse is very weak and the vein is not fully developed. The exact site of the stenosis can be felt as an abrupt diminution in the size of the vein.20 Stenosis at the anastomosis site will reduce blood flow into the AVF. A stenosis higher up – above the venous needle site – will increase pressure within the fistula, reduce blood flow and increase the percentage of recirculation, all of which can affect the efficacy of dialysis. During dialysis high venous pressure or negative arterial pressure are indicators of recirculation, and thereby stenosis of the AVF.23,27

ManagementRegular physical examination of the AVF (before and after each haemodialysis session) should reveal the problem. The patient should be taught to inspect his/her AVF on a daily basis. Regular monitoring of the AVF can detect stenosis early and prevent under-dialysis.23

Duplex ultrasonography can confirm the diagnosis of ste-nosis, irrespective of its location. The precise location and


101

diameter of the stenosis should be recorded for further inter-ventions.

Early detection facilitates correction of the stenosis (by angioplasty or surgical revision) prior to thrombosis.23 Stenosis should be treated if the diameter is reduced by more than 50%, otherwise it will cause reduced access flow and decreased dialysis dose.22 A surgical reconstruction should be considered in stenosis located at the arterial side of the AVF.20,32

Angiographic or surgical revision of the AVF to correct the stenosis before the occurrence of thrombosis can reduce the rate of thrombosis and loss of AVF.23,33,34

According to recent literature the buttonhole cannulation technique is likely to minimise the risk of area dilatation, and subsequent aneurysm and stenosis.35

9.2 Thrombosis

DefinitionThe formation of a clot (thrombus) in the AVF is defined as thrombosis. In AVF, thrombosis is the leading cause of loss of AVF patency.21

AetiologyAVF thrombosis can occur either soon after its creation or as a late event. Hypotension, during or after haemodialysis, infection and hypercoagulability may precipitate thrombosis.22,23 AVF thrombosis is often related to venous stenosis (outflow vein or central venous drainage), or stenosis within the conduit or the arterial anastomosis, resulting in reduced blood flow.21,27 Another cause includes constriction of blood flow, by occlusion of the access with tight bandages or clamps


102102

during haemostasis, by falling asleep on the fistula arm, or by haematoma formation after extravasation.22

Signs and symptomsThe patient is often the first to notice a loss of palpable pulse or thrill in the AVF. Close examination of the AVF may reveal loss of bruit and thrill and on aspiration of the clot the absence of blood when the AVF is cannulated.21,27 Nurses can easily suspect thrombosis when poor flow of the AVF is present during haemodialysis. Thrombosis may be accompanied by increased flow volume in collateral veins or increased distal oedema. High fibrinogen levels, reduced levels of protein S or protein C, factor V Leiden mutation, or lupus anticoagulant should be taken under consideration. Haematocrit levels >40% are associated with increased risk of thrombosis.23 Parameters that predispose towards thrombosis formation following dialysis include: low blood pressure (most common cause) and haemoconcentration (due to excessive ultrafiltration and firm or prolonged compression of the AVF for haemostasis).26

ManagementAn organised monitoring approach including regular assess-ment of the clinical parameters during dialysis as well as the dialysis dose is crucial. Trends in these variables are very important. Careful assessment of Erythropoiesis Stimulating Agents (ESA) response and blood pressure is part of reducing risk.

Patient and carers should also be educated in examination of their access and be given clear instruction in the event of suspected thrombosis. If a thrombosis is suspected, a Dop-pler ultrasound can demonstrate the absence of flow,35 but the use of fistulography can confirm thrombosis and allow access retrieval. Pharmacological prevention of thrombosis is contro-


103

versial. Warfarin may be prescribed to these patients, but at-tention should be given to patients with protein S or protein C deficiency (as warfarin can precipitate skin necrosis) and those with lupus anticoagulant (note that prothrombin time is an unreliable measure of anticoagulation).23 Aspirin and Clopi-dogrel have also been recommended, but evidence is limit-ed. In all cases, the use of these drugs must be weighed up against the risk of side effects in a vulnerable population. When occlusive thrombosis is present interventional radiology is the most common approach although surgical thrombectomy may be an alternative, especially for new access. In either case, firstly it is important to determine the cause of the thrombosis, if possible.32 Interventional radiological methods are used to confirm the diagnosis of AVF thrombosis. A fistulogram can demonstrate the exact area of obstruction in the AVF. Surgi-cal treatment (thrombectomy) may be indicated, but salvage of the AVF may often be unsuccessful. Percutaneous angio-plasty using a balloon-tipped embolectomy catheter may be more successful in thrombus removal.23,31 Thrombolysis with urokinase or other agents (tissue plasminogen activator [tPA], alteplase, and streptokinase) may be an alternative delivered to the access via a fistula needle. The use of heparin may also be adjunct to intervention, either before a procedure or after, but evidence is lacking or not proven.

9.3 Aneurysms

DefinitionAneurysms are abnormally dilated focal regions of a blood vessel (>150% of the AVF diameter). An aneurysm contains all the layers of the vessel wall.


104104

An aneurysm of the AVF is a localised enlargement (or bulging)20 of the vessel wall, at least 1.5 times the size considered normal for the segment.

AetiologyThe aetiology of aneurysms in AVF is unclear, but it is suggested that increased venous pressure due to a central venous stenosis, repeated cannulations at the same site (area technique), and immunosuppression may be involved.36,37

Aneurysms are primarily caused by the use of the area cannulation technique. The skin gradually becomes thinner in result of destruction of the vessel wall and replacement by scar tissue after repetitive cannulation of the same vessel segment as the aneurysms dilate. Infection also can cause aneurysms. Aneurysms are also associated with the development of stenosis of the vein above the needling site. A pseudo-aneurysm of the venous limb results from inadequate haemostasis and extravasation of blood following dialysis needle removal (refer to chapter 8.6.2).20,21,23

Signs and symptomsEnlargement and saccular dilation of the AVF, ulceration of the overlying skin, rupture, haemorrhage and lesions.20,23

ManagementAneurysms should be observed and the affected area avoided during cannulation.20,23 Repair of the aneurysm or bypass can often be performed without the need for a temporary dialysis catheter. The AVF must be repaired when aneurysms enlarge and become filled with thrombi, the skin becomes thin, and spontaneous bleeding or limitation at needling sites, or nerve compression, occurs. A surgical repair can be performed for


105

cosmetic/aesthetic reasons if the patient is uncomfortable with his/her appearance.20

9.4 Complications caused by the Arteriovenous Fistula9.4.1 Cardiac complications

DefinitionThe presence of an AVF, specially proximal with high flow, demands a high cardiac output. This situation can cause an exacerbation of pre-existing conditions for Congestive Heart Failure (CHF).

AetiologyCHF may occur in patients with upper arm or femoral fistulae,23 and has been related to the presence of large vessel AVF or the presence of multiple AVFs.38 The access flow rate through an AVF varies from 400 mL per minute to 2000 mL per minute (AVG). CHF may result from systolic or diastolic dysfunction due to left ventricular hypertrophy (LVH).

Signs and symptomsDyspnoea, jugular vein distension, bilateral lung crepitations.

ManagementEchocardiography is used to assess left ventricular (LV) dimensions and function. Regular chest X-rays should be performed in order to assess the cardiothoracic index.39

Surgical intervention (narrowing or banding) in a functioning AVF should be performed when changes in cardiac output are present. Long-term cardiac function is unaffected by the presence of AVFs in most patients.23,38


106106

9.4.2 Steal syndromeDefinitionSteal syndrome is defined as a diversion of blood flow from excessive its natural route within the AVF, resulting in ischaemia of the limb (see Figure 27).

Patients with normal radial and/or ulnar pulses are unlikely to develop steal syndrome. It is common in patients with co-existing vascular disease, diabetes, narrow arteries, absent wrist pulse, Raynaud’s phenomenon, amputations, vasculitis, and patients who have had multiple AVF attempts.21,23,30,40 It can have serious consequences for an individual, ranging from access loss to loss of function of the limb through neurological or ischaemic damage, or pain during dialysis.

Figure 27. Ischemic signs of steal syndrome

AetiologyLow arterial pressure at the fistula site resulting from excessive diversion of artery blood to the anastomosed vein is the main cause of steal syndrome. During the AVF creation, the radial artery distal to the AVF is usually connected, to the ulnar artery. In steal syndrome, high blood flow volume through an


107

arteriovenous anastomosis may cause stealing of blood from forearm arteries. This steal can lead to distal hypoperfusion and produce peripheral ischaemia

The radial artery anastomosis steals blood from the ulnar artery system, and blood destined for the hand and fingers is shunted through the arterial-venous anastomosis, depriving the extremity of required oxygenation. This is due to the difference in resistance to flow presented by the AVF and the microcirculation of the hand.22,23,30

Signs and symptomsPhysical findings depend upon the severity of the problem and the pre-existence of peripheral circulation. Coldness and paraesthesia (numbness and tingling) without sensory or motor loss can be the first signs. The radial pulse may be diminished or absent. Pain in the hand during exercise, coldness and numbness during haemodialysis, mononeuropathy with intrinsic muscle weakness in the hand, rest pain in the affected extremity, appearance of non-healing ulcers and gangrene can be present in the later stages.21,23

ManagementAn Allen test can be used to predict steal syndrome prior to AVF creation, but it is not an accurate predictor. During physical examination of a patient with a cold and painful arm, a comparison of the affected side versus the non-affected side and assessment of the radial pulse in both extremities is helpful. The diagnosis can only be confirmed with the use of a Doppler stethoscope. Baseline digital blood flow at the finger level should be checked and compared with subjective flow patterns before and after temporary access site occlusion. If occlusion leads to increased flow with visible hyperaemia of digits, the diagnosis is confirmed. Pulse volume records and


108108

colour flow duplex ultrasound are used to evaluate the flow in the extremities.21

For minor steal syndrome (early detection), it is recommended that the access site is revised (repaired). The most common procedure is called Distal Revascularisation-Interval Ligation (DRIL), where the hand is re-vascularised with a bypass and the interval artery is ligated. For major steal syndrome that is threatening to the limb, an urgent procedure should be scheduled. This may include a new arterial inflow site, bypass around the access site, flow limitation of the limb and thrombectomy.21,23


109

Arteriovenous Fistula Monitoring and Evaluation

111

111


112112

10 Arteriovenous Fistula monitoring and evaluation

Early identification of possible complications is the most important challenge to maintain the long-term patency of the AVF.

It is important always to perform assessment of the AVF before, during and after each dialysis session.

10.1 Arteriovenous Fistula monitoring

10.1.1 Dynamic venous and arterial pressures evaluation

Arterial pressureAn increased dynamic negative arterial pressure during consecutive dialysis sessions could also be a sign of AVF stenosis or low access flow. Pre-pump arterial pressure (AP) monitoring helps to make sure the correct blood flow is delivered through the extra-corporeal blood circuit. It also prevents a non-functioning vascular access from being used.

Venous pressureAn increased dynamic venous pressure during consecutive dialysis sessions is more significant than a single high value under the same technical conditions.27 Patients with increased dynamic venous pressures during consecutive sessions require venography or a Doppler ultrasound examination to investigate for venous stenosis.

‘Measuring dynamic venous and arterial pressures is the least expensive and easiest method of surveillance available, although very few studies have evaluated its utility in AVFs, and some found a low accuracy for stenosis detection, whereas others reported that measuring the ratio of dialysis


113

blood pump flow (Qb) to negative arterial pressure (Qb/AP) can predict AVF inflow stenosis’.41

10.1.2 Measurements of blood recirculationBlood recirculation measurement may indicate a stenosis in the AVF. Nevertheless it will be a late diagnosis.

There is more than one method available to evaluate blood recirculation.

Blood sampleTwo-needle measurement of blood recirculation comprises the following steps and should be performed after 30 minutes of dialysis with ultrafiltration switched off:

• Take arterial (A) and venous (V) blood samples from the respective lines

• Reduce the blood flow rate to 120mL/min for 10 sec then switch off the blood pump Clamp the arterial line above the sampling port and take a systemic arterial sample (S) from the arterial line

• Continue dialysis• Measure urea levels in the A,V and S samples27

• Recirculation is defined as S–A/S–V x 100

ThermodilutionThe thermodilution method makes it possible to determine the total blood recirculation with a non-invasive temperature bolus technique, and thus detect vascular problems that could reduce the efficacy of dialysis. This method can be used to assess both fistula and cardiopulmonary recirculation. If the value is lower than 10%, recirculation is categorised as ‘low’; this may be due to cardiopulmonary recirculation only. A value


114114

higher than 20% indicates considerable fistula recirculation and the fistula should be examined for the presence of any possible stenosis.42

10.1.3 Dialysis efficiency If dialysis efficiency as expressed by Kt/V, urea reduction rate (URR), is decreasing, one of the explanations for this can be the presence of an AVF stenosis. Serum potassium, phosphate, urea and creatinine levels will be elevated.

10.1.4 Arteriovenous Fistula instrumental evaluationAccess flow The presence of a palpable thrill is associated with an access flow >450 mL/min. An access flow of 800–2000 mL/min is accepted as normal.27 When access flow falls below 400 mL/min the risk of VA thrombosis increases. A trend of reduced access flow values is a very important predictive factor for stenosis. Therefore, consecutive measurements are more useful than a single measurement.33 Doppler ultrasound is one of the methods of access flow measurement.

AngiographyAngiography is an imaging technique used to visualise the inside, or lumen, of the AVF. This is traditionally done by injecting a radio-opaque contrast agent into the blood vessel.

Patients with suspected venous or arterial stenosis require angiography of the AVF from the arterial inflow up to the venous outflow as far as possible. Care should be taken during these examinations, as the effect on residual renal function of using contrast media could be detrimental. When performing angiography, interventional procedures can be done simultaneously, resolving the cause of access dysfunction.


115

Doppler ultrasoundDoppler ultrasound provides accurate anatomical and haemodynamic information, also measuring the access flow (even in patients whose AVF has not yet matured). This examination can be performed as part of a routine surveillance programme, to detect early an AVF problem, or suspected dysfunction.

Magnetic resonance flow measurementsThis is an accurate but very expensive procedure.43 Recently, Contrast-Enhanced Magnetic Resonance Angiography (CE-MRA) has been introduced for examining failing VAs. CE-MRA is non-invasive, does not use ionising radiation, and provides an angiographic map of the complete vasculature of the VA. However, a major limitation of CE-MRA is the absence of magnetic resonance-guided access intervention.44 In addition, nephrogenic systemic fibrosis has been reported with the use of gadolinium in dialysis patients.

Reporting of Arteriovenous Fistula Incidents

117

117


118118

11 Reporting of Arteriovenous Fistula IncidentsAVF dysfunction remains a major contributor to morbidity and mortality of haemodialysis patients. Regular monitoring and surveillance of all risk factors related to AVF internal character-istics, as well as any comorbidity that may influence its func-tion and preservation, are recommended.44

External risk factors associated with cannulation techniques should also be encompassed by regular assessment param-eters to identify risks or complications associated with dys-function to either prevent thrombosis or to intervene in a timely manner to correct any incident and address the causes.

11.1 What, When and Why to reportAll factors that might influence the patency and survival of the AVF should be reported. Many of the risk factors for AVF failure are associated with comorbid conditions that decrease the likelihood of its survival.

Current guidelines recommend that vascular access monitoring and surveillance are part of the dialysis care provided to patients with ESRD in order to identify problems and intervene at an early stage.

Prevention is better than cure! Early diagnosis translates into early intervention prolonging access patency and survival. It is important to clarify, that surveillance and monitoring are complementary and must be combined.

Primary AVF failure related to poor development and maturation of the fistula prior to the first cannulation as well as dysfunction or complications associated with the AVF’s patency and functionality, must be reported as described in table 7.


119

Tabl

e 7:

Rep

ortin

g AV

F co

mpl

icat

ions

Prob

lem

sid

entifi

edW

hat t

o re

port

Whe

n to

repo

rtW

hy to

repo

rt

Failu

re

of A

VF

mat

urat

ion

Sw

ellin

g in

the

limb

A w

eak

puls

e (h

ypop

ulsa

tion)

,45

poor

or a

bsen

t thr

ill/

brui

t

Whe

n sw

ellin

g do

es n

ot

resp

ond

to a

rm e

leva

tion

or p

ersi

sts

beyo

nd 2

w

eeks

afte

r AV

F cr

eatio

n

On

asse

ssm

ent

Ear

ly re

cogn

ition

of a

dy

sfun

ctio

nal A

VF

can

prov

ide

an o

ppor

tuni

ty

for t

imel

y in

terv

entio

n du

ring

mat

urat

ion

that

may

pr

even

t the

loss

of t

he A

VF

If a

thro

mbo

sed

AVF

is

reco

gnis

ed w

ithin

48

hour

s an

d th

e pa

tient

is re

ferr

ed

imm

edia

tely

to a

vas

cula

r ac

cess

cen

tre, t

hat m

ay

prev

ent t

he lo

ss o

f the

AV

F33,4

6


120120

Prob

lem

sid

entifi

edW

hat t

o re

port

Whe

n to

repo

rtW

hy to

repo

rt

Hae

mat

oma/

infil

trat

ion

All

even

ts o

f in

filtra

tion

Pre

senc

e of

ha

emat

oma

incl

udin

g si

ze a

nd a

ffect

ed a

rea

Inco

rrec

t use

of

cann

ulat

ion

tech

niqu

e

As

soon

as

the

infil

tratio

n ta

kes

plac

e an

d/or

hae

mat

oma

appe

ars

Ear

ly re

cogn

ition

of a

n ha

emat

oma

can

prev

ent

the

risk

of th

rom

bosi

s an

d/or

ste

nosi

s

Incr

ease

d ha

emos

tasi

s tim

e

Pro

long

ed b

leed

ing

time

afte

r nee

dle

rem

oval

Whe

n pr

olon

ged

blee

ding

tim

e oc

curs

on

at le

ast t

wo

cons

ecut

ive

treat

men

ts

Pro

long

ed b

leed

ing

may

be

a p

redi

ctor

of s

igni

fican

t ce

ntra

l vei

n st

enos

is,

inad

equa

te a

ntic

oagu

latio

n th

erap

y, o

ther

com

orbi

ditie

s (e

.g. l

iver

failu

re)


121

Prob

lem

sid

entifi

edW

hat t

o re

port

Whe

n to

repo

rtW

hy to

repo

rt

Sign

s of

In

fect

ion

The

patie

nt p

rese

nts

with

sig

ns/s

ympt

oms

of in

fect

ion

(ref

er to

ch

apte

r 8.6

.3)

Pre

senc

e of

an

eury

sms,

infe

cted

th

rom

bi o

r loc

alis

ed

absc

ess

form

atio

n

As

soon

as

any

sign

s of

in

fect

ion

are

reco

gnis

edR

epor

ting

can

decr

ease

pa

tient

mor

bidi

ty a

nd

cost

s as

soci

ated

with

ho

spita

lisat

ion.

Var

ious

re

ports

indi

cate

that

the

mos

t fre

quen

t cau

se o

f ho

spita

lisat

ion

amon

g E

SR

D p

atie

nts

is

com

plic

atio

ns a

ssoc

iate

d w

ith th

e VA

6

Sign

s of

A

neur

ysm

A la

rge

aneu

rysm

is

pres

ent a

nd s

how

s si

gns

of fr

agili

ty o

r ru

ptur

eTh

e an

eury

sm

show

s pr

ogre

ssiv

e en

larg

emen

t as

soci

ated

with

de

velo

pmen

t of l

ocal

or

pro

xim

al s

teno

sis

The

aneu

rysm

has

a

poor

thril

l and

stro

ng

puls

e

As

soon

as

an a

neur

ysm

is

reco

gnis

edR

efer

ral a

nd in

terv

entio

n fo

r lar

ge a

neur

ysm

s ca

n pr

even

t pos

sibl

e ru

ptur

e an

d ha

emor

rhag

e, s

ever

e bl

eedi

ng, a

nd c

an b

e fa

tal

for t

he p

atie

nt

Thes

e pa

tient

s sh

ould

be

refe

rred

imm

edia

tely

to

furth

er in

vest

igat

ion

and/

or in

terv

entio

n to

sav

e th

e AV

F


122122

Prob

lem

sid

entifi

edW

hat t

o re

port

Whe

n to

repo

rtW

hy to

repo

rt

Sign

s of

St

enos

is

loca

ted

upst

ream

(fr

om th

e an

asto

mos

is

to a

rteria

l ca

nnul

atio

n si

te)47

Dim

inis

hed

acce

ss

inflo

w c

hara

cter

ised

by

ele

vate

d ne

gativ

e ar

teria

l pre

-pum

p pr

essu

res

Red

uced

thril

l an

d al

tere

d pu

lse

char

acte

ristic

s.

Poo

r blo

od fl

ow w

ith

diffi

culti

es to

ach

ieve

th

e pr

escr

iptio

n

Whe

n th

ere

is s

igni

fican

t de

crea

se in

thril

l as

soci

ated

with

a w

eak

puls

e W

hen

elev

ated

neg

ativ

e ar

teria

l pre

-pum

p pr

essu

res

prev

ent

achi

evin

g th

e pr

escr

ibed

bl

ood

flow

In c

ase

of in

adeq

uate

bl

ood

flow

con

firm

ed

on tw

o co

nsec

utiv

e tre

atm

ents

The

pres

crib

ed K

t/V

with

in d

efine

d di

alys

is

dura

tion

is n

ot a

chie

ved

(e.g

. una

ble

to p

rovi

de

eKt/V

≥1.

2 in

a 4

-hou

r di

alys

is s

essi

on).

Une

xpla

ined

low

Kt/V

(e

.g. e

Kt/V

<1.

2 in

a

4-ho

ur d

ialy

sis

sess

ion)

Reg

ular

mon

itorin

g of

bl

ood

flow

can

pre

dict

th

e pr

esen

ce o

f AV

F m

alfu

nctio

n an

d pr

ovid

e an

opp

ortu

nity

for e

arly

in

terv

entio

n to

pre

vent

or

redu

ce th

rom

bosi

s in

the

fistu

lae4,

47

The

corr

ectio

n of

the

sten

osis

incr

ease

s th

e ef

fect

iven

ess

of d

ialy

sis

and

decr

ease

s m

orbi

dity

ra

tes

for p

atie

nts


123

Prob

lem

sid

entifi

edW

hat t

o re

port

Whe

n to

repo

rtW

hy to

repo

rt

Sign

s of

St

enos

is

loca

ted

dow

nstr

eam

(fr

om

veno

us

cann

ulat

ion

site

to

cent

ral

vein

s)

Ele

vate

d dy

nam

ic

or s

tatic

ven

ous

pres

sure

s

Pro

long

ed b

leed

ing

time

afte

r nee

dle

rem

oval

Pre

senc

e of

oed

ema

Dev

elop

men

t of

mul

tiple

col

late

ral

drai

ning

vei

ns p

rese

nt

at s

ome

dist

ance

fro

m th

e an

asto

mot

ic

site

(e.g

. ove

r the

ch

est)

Per

sist

ent s

wel

ling

in th

e AV

F ar

m w

ith

oede

ma

of th

e sh

ould

er,

brea

st, s

upra

clav

icul

ar,

neck

and

face

, and

an

abno

rmal

arm

ele

vatio

n te

st46

Per

sist

ent p

ain

in th

e AV

F du

ring

treat

men

t

Pat

ient

has

pro

gres

sive

ly

incr

easi

ng in

tra-a

cces

s ve

nous

pre

ssur

e

Reg

ular

mon

itorin

g of

ac

cess

blo

od fl

ow c

an

pred

ict t

he p

rese

nce

of A

VF

mal

func

tion

and

prov

ide

an o

ppor

tuni

ty fo

r ear

ly

inte

rven

tion

to p

reve

nt o

r re

duce

thro

mbo

sis

in th

e fis

tula

e4,47

Reg

ular

sur

veill

ance

of

the

AVF

is re

com

men

ded

for d

etec

ting

and

treat

ing

sten

osis

and

in o

rder

to

prev

ent t

hrom

bosi

s an

d fa

ilure

. Ear

ly d

iagn

osis

of

fistu

la d

ysfu

nctio

n fo

llow

ed

by a

ngio

plas

ty o

r ele

ctiv

e su

rger

y ca

n re

pair

and

prol

ong

fistu

la fu

nctio

n.

Rem

oval

of t

he th

rom

bosi

s is

effe

ctiv

e in

mor

e th

an

90%

of c

ases

33


124124

Prob

lem

sid

entifi

edW

hat t

o re

port

Whe

n to

repo

rtW

hy to

repo

rt

Sign

s of

Ste

al

synd

rom

e

A di

ffere

nce

in

tem

pera

ture

bet

wee

n th

e fin

gers

of t

he

hand

on

the

AVF

limb

and

the

cont

rala

tera

l lim

b

Poo

r arte

rial b

lood

flo

w to

the

hand

due

to

hig

h flo

w th

roug

h th

e AV

F

Isch

aem

ic p

ain

at

rest

acc

ompa

nied

by

atro

phic

cha

nges

su

ch a

s ul

cera

tion,

ne

cros

is a

nd

gang

rene

As

soon

any

sig

ns o

f st

eal s

yndr

ome

have

be

en d

etec

ted

(Ste

al

synd

rom

e of

the

limb

can

be e

asily

con

firm

ed

by a

skin

g th

e pa

tient

ab

out s

ympt

oms,

or b

y ph

ysic

al e

xam

inat

ion)

Rep

ort w

hene

ver t

he

patie

nt h

as a

pal

e or

co

ld h

and

with

or w

ithou

t pa

in d

urin

g ex

erci

se

and/

or h

aem

odia

lysi

s

Red

ucin

g or

cor

rect

ing

the

prob

lem

s as

soci

ated

with

di

stal

lim

b is

chae

mia

can

pr

even

t los

s of

lim

b an

d AV

F


125

Prob

lem

sid

entifi

edW

hat t

o re

port

Whe

n to

repo

rtW

hy to

repo

rt

Inad

equa

te

Blo

od F

low

The

pres

crib

ed b

lood

flo

w is

not

ach

ieve

d du

ring

the

treat

men

t

Whe

n th

e bl

ood

flow

rate

is

less

than

pre

scrib

ed

valu

e

Whe

n el

evat

ed n

egat

ive

arte

rial p

re-p

ump

pres

sure

s, p

reve

nts

achi

evin

g th

e pr

escr

ibed

bl

ood

flow

, thu

s re

duci

ng

dial

ysis

effi

cacy

Blo

od fl

ow ra

tes

is le

ss

than

pre

scrib

ed v

alue

may

le

ad to

und

er-d

ialy

sis

and

may

indi

cate

urg

ent n

eed

of A

VF

revi

sion

Reci

rcul

atio

nR

ecirc

ulat

ion

valu

es

exce

edin

g 5%

Dur

ing

surv

eilla

nce

mea

sure

men

ts u

sing

the

non-

urea

-bas

ed d

ilutio

n m

etho

d

Ear

ly re

porti

ng o

f fist

ula

dysf

unct

ion

is im

porta

nt to

co

rrec

t, be

fore

the

loss

of

vasc

ular

acc

ess

occu

rs.

The

nurs

e sh

ould

repo

rt al

l cha

nges

in th

e AV

F an

d ris

k fa

ctor

s as

soci

ated

with

th

e AV

F’s

pate

ncy

and

func

tiona

lity

to p

reve

nt it

s fa

ilure

Rec

ircul

atio

n va

lues

ex

ceed

ing

10%

Dur

ing

surv

eilla

nce

mea

sure

men

ts u

sing

the

two-

need

le u

rea-

base

d di

lutio

n m

etho

d

Rec

ircul

atio

n va

lues

ex

ceed

ing

20%

Cha

nges

of t

he n

eedl

e pl

acem

ent


126126

Reporting responsibilities

Each dialysis unit should appoint a vascular access coordinator to manage the database and the referral of patients with dysfunction related to the patency/survival of the AVF.

For better assessment, bimonthly multidisciplinary meetings should discuss the data of those patients presenting with dysfunctional factors, which will require further investigation.

Before each treatment, the nurse must perform an assessment, report the findings and change the haemodialysis treatment plan if required.

According to the protocol established in the dialysis unit, the vascular access coordinator must notify the physician responsible for the patient regarding all findings. To ensure timely and effective actions, the multi-disciplinary team must use the same reporting language, therefore providing consistency of communication.

Studies indicate that the introduction of these protocols are very important because it can achieve a higher primary and secondary patency therefore resulting in lower patient morbidity.19,48

11.2 Reporting toolsDialysis unit should establish a protocol for monitoring and surveillance of vascular access, and define methodologies for reporting the findings. Tools must be created to store the data collected either manually or electronically.

11.2.1 Paper chartsA programme for monitoring and surveillance should be created for each unit in order to collect the data relating to


127

the patient’s AVF. The results and findings of the vascular access monitoring (physical examination and/or surveillance test) should be inserted into the database. The vascular access coordinator should do a systematic observation of the findings, correlating various factors monitored in the charts. Trend analysis is more useful than any single measurement and should be used to predict and prevent access failure.

The tool should include the biographic data from each patient, along with the following factors related to AVF:

• Location• Access flow• Recirculation• Needle gauge used• Cannulation technique and complications• Distance between cannulation sites/needle tips• Changes observed in the physical examination• Bleeding associated with needle removal• Hospitalisations related to AVF complications

11.2.2 E-chartsThe data from all treatments may be collected in electronic format directly from the haemodialysis machines and inserted into a computerised data file. In this way, a computerised database for documentation of procedures and complications is developed for all patients. This programme should be managed by a vascular access coordinator who will undertake the analysis of the data.

This database could also include all of the items described above which can be inserted manually. Each unit should build its own database including biographic data from each patient.


128128

To facilitate analysis, an algorithm can be formulated to generate an automatic warning if there is a deviation in the indicators of AVF dysfunction.49

The data collected and related to VA should include:

• Arterial pressure ratios• Venous pressure ratios• Average flow rate of the blood pump• Dialysis dose (Kt/V)

11.3 Corrective actions Before referral, the causes of dysfunction should be deter-mined. Depending on the results, refer the patient for angio-plasty and/or vascular surgery.

• If the test indicates the presence of stenosis, either upstream or downstream, this can be confirmed by venography or fistulography. The stenosis of AVFs can be corrected using angioplasty. When recurrent stenosis is dependent on the location, it may need surgical revision. These interventions can substantially reduce the number of thromboses and avoid the need to construct a new access

• AVF thrombosis can be rescued within 48 hours using angioplasty or surgical revision. Several studies have demonstrated that such interventions can reduce the number of access replacements and prolong the use-life of the fistula

• Fistulae that fail to mature due to multiple collateral draining veins can be corrected with surgical interven-tion. Collateral vein obliteration results in high salvage rates for these immature fistulae


129

• Fistulae with adequate diameter and blood flow, but too deep to be cannulated, can be treated surgically to facilitate cannulation

• AVF with aneurysms, localised abscess formation and risk of rupture may require surgical intervention and excision

• Large aneurysm formation can lead to fistula failure with thrombosis or possible rupture and death. Vascular surgeons can develop local strategies for repair interventions

• Patients with signs and symptoms of severe ischaemia should be referred to a VA surgeon immediately.

11.4 Follow-up of corrective actions Regular monitoring and surveillance, allows the multidisciplinary team to be involved in a coordinated structured manner in the identification of patients with dysfunction or incidents in the fistula.

• Hygiene and aseptic procedures should be re-evaluated to ensure that they are being correctly followed

• The cannulation technique in use should be re-assessed to check that it is the most appropriate (Area cannulation is the least favoured technique)

• Patient and staff education levels should be re-evaluated in order to additional future educational needs

• The AVF should be evaluated after an interventional procedure, in order to assess the surgical intervention efficacy

Patient Education for the Care of Arteriovenous Fistula

131

131


132132

12 Patient education for the care of Arteriovenous FistulaPatient education/information is a powerful tool in helping to maintain the AVF’s patency, and guarantee successful dialysis therapy. For patients, diagnosis of CDK is a traumatic event that can lead to stress and depression. To reduce the risk of these events, patients should be given as much information as possible. The Internet has a wealth of information available for dialysis patients with a few clicks of a mouse. Information resources range from basic explanations of dialysis procedures and technology to more complex technical terminology.

For CKD patients, like with other chronic illness, families may also need the same knowledge as the patient to help them with decision making in relation to many aspects of the disease such as the care of vascular access and its preservation.

The learning process should start as soon as the patient is diagnosed with CKD 4 and/or referral to pre-dialysis care and/or CKD 4 management. This timing gives the patient, their family and carers an understanding of the choices regarding the type of replacement therapy and vascular access options.

Whilst important, patient education means more than provid-ing information. In addition to information, most CKD patients benefit from counselling in how to participate actively in their care and to self-manage the tasks needed to optimise their health successfully. This vital part of patient education is need-ed to increase patients’ skills and confidence in managing their health problems.

Each CKD unit should have a written education plan for pa-tients and carers. During the education sessions the nurse needs to remember that uraemia, depression, age, denial, anger, etc. are factors that might cause problems and delays in the patient understanding the information. In addition, CKD


133

patients may not have patience for long teaching sessions; they are most likely to remember what they were taught in the first 10 minutes of the session. Written material is essential for the success of the education.

Patient education doesn’t mean simply handing over informa-tion. The patient and carer’s understanding of the information given should be checked during each session and at the be-ginning of the following one.

Written materials, pictures and discussions with patients already in haemodialysis may also be a very helpful educating tool.

12.1 Preservation of vessels prior to Arteriovenous Fistula creation

Whether patients choose haemodialysis or peritoneal dialysis, it is of utmost importance that they should be aware of how they can help to preserve the vessels in both arms. This will have a great impact on the creation of an AVF. Even patients who opt initially for peritoneal dialysis may need haemodialysis in the future.

Patients need to be aware from the beginning that the AVF represents their connection to life,

and that their creations are not endless

Early detection of problems and a prompt intervention are essential for a long-lasting AVF

The patient must be aware that at each admission at the hospital or the healthcare interaction, following activities should be avoided:


134134

• the use the major vessels and the vessel located in the antecubital fossa for: * Blood sampling * Intravenous (IV) injections and infusions * Invasive arterial pressure measurement

• the use of upper arms veins for: * Catheterisation (e.g. Angiography) * Radiological investigation (contrast medium substances)

• Instead use the veins of the hand and minor vessels• Patients should be informed about the possible

use medium of contrast if that will be used for the examination and they should be inquired regarding allergy. The results of the investigation, as well as any possible intervention, should be carefully explained to the patient

12.2 Arteriovenous Fistula care12.2.1 CreationWhen the patient has been informed about the creation of an AVF and what to expect after the surgery, they must then be supported to understand that if side effects or important changes occur, they should immediately contact the CKD unit.

Important advice after surgery includes:

• Keep the arm warm and dry after surgery• Monitor the surgical wound for changes in temperature,

redness, pain levels and drainage, and contact the CKD staff if any of these observations are present

• Elevate the arm slightly if swelling is present (and contact CKD staff as soon as possible)


135

• Ask the nurse to inspect the new AVF at each session if already on dialysis treatment via a CVC

Important general advice includes:

• Use the other hand to feel the thrill three times a day• Avoid sleeping on the AVF arm• Avoid wearing tight sleeves that may act as a tourniquet

on the AVF or on the vessels above the AVF• Avoid carrying heavy weights (e.g. while shopping,

lifting children, lifting furniture, or at the gym)• Avoid violent sports or activity that may cause a trauma

to the AVF• Make sure that staff are made aware of the presence

of the AVF via signalling bracelet and avoid blood pressure measurements, blood sampling and IV injections or infusions on the AVF arm in case of hospital admission

12.2.2 Arteriovenous fistula maturationInform patients that during the maturation period they need to pay special attention to their vascular access arm. For this time the AVF area should be covered with a light bandage/dressing to protect it from infection and to keep it safe. Periodically, the nurse or the physician will examine the AVF.

After the surgery it is very important that patients understand and adhere to the recommendations regarding all aspects of AVF care. Patients should be advised to follow an appropriate exercise programme for the maturation of the AVF. Exercises should start when the wound is healed and after removal of the stitches.

Here are some simple exercises that patients can practise several times a day:


136136

• Grab a clothes peg (see Figure 28) * Take a normal clothes peg * Squeeze it open with the index finger and thumb, allowing it to close again

* Repeat this exercise for 5 minutes, six times a day

Figure 28. Clothes peg

• Squeeze a soft ball (see Figure 29)

* Hold the ball in the hand of the AVF arm * Let the arm hang down beside the body * Squeeze the ball by opening and closing the hand repeatedly for about 5 minutes

Figure 29. Squeeze soft ball


137

• Touching the fingertips (see Figure 30) * Touch each finger ‘to’ the tip of the thumb, repeating this action for 5 minutes

* Open the hand after each touch * Touch fingertips to thumb repeatedly for 5 minutes, six times a day

Figure 30. Touching fingertips

12.3 Protect the lifeline – things to consider in the patient’s daily life

Remind patients that the AVF requires checking every day using their eyes, ears and fingers.

Educate patients to:

• Recognise signs of redness and swelling when looking at AVF arm

• Use a stethoscope if possible to check if there is a good blood flow through the AVF; and teach them to recognise the ‘bruit’ sounds

• Use palpation, to feel a rhythmic vibration/buzzing sensation (thrill) by putting their hand on the AVF.


138138

Remind them that when palpating their AVF, to pay special attention if it feels sore or warmer than usual

Educate patients on the importance of hygiene for the AVF in order to avoid any possible migration of bacteria from the skin to the blood circulation system, which could lead to infection, advise patients to:

• Wash their access arm with water and soap every day and particularly before each dialysis session

• Avoid coughing or sneezing in the direction of the AVF• Keep the haemostatic or adhesive plaster in situ for up

to 3–4 hours after haemostasis (depending on local policy) and refrain from scratching the AVF area – especially the cannulation sites

Teach patients the importance of maintaining a constant temperature in the area of the AVF. The patients must be aware that:

• Excessive heat (e.g. saunas or steam baths) induces vessel dilation and reduces the blood pressure and blood flow. If the patient wants to be outside on a very hot day, they should try to stay in the shade

• Excessive cold induces vessel constriction and hence reduces blood flow in the limbs, especially in the AVF arm. On extremely cold days, remind patients to wear appropriate warm clothes if they want to go out for some fresh air

12.4 Arteriovenous Fistula complications Patients should be educated and informed on how to recognise the following complications and any treatments that may be


139

required. It should be very clear to patients that when they feel that ‘something is wrong’ they should immediately contact their dialysis unit. Patients should be taught to recognise the following signs.

Prevention and signs of infectionPatients must be educated:

• To perform hand washing before and after each treatment

• To recognise, prevent and report any signs and symptoms of infection, such as: * Redness * Fever * Swelling, warmth to touch * Pain * Exudate

Always keep in mind that S. aureus is the most common pathogen and if there is any sign of infection advise the patient to contact the dialysis unit immediately and report the signs and symptoms to the unit staff. Advise the patient that blood cultures may be required and that a course of antibiotics may be given. Re-educate the patient on the importance of hygiene and access care.

HaematomaAn untreated clot can reduce the blood flow in the AVF and may cause thrombosis. Clotting in the AVF can be caused by several reasons such as:

• Excessive use of pressure at haemostasis• Hypotension


140140

Dehydration may be due to excessive fluid removal during the treatment, or diarrhoea and/or vomiting. This may cause a reduced flow of blood through the fistula and possible clotting. It is important to educate patients and to involve them in their care in order to minimise the risks. Educate the patient to:

• Monitor the AVF daily and report any changes• Apply appropriate pressure at haemostasis and for an

appropriate time• Recognise the signs and symptoms of hypotension

Bleeding

It is not uncommon for dialysis patients to present with bleeding from their AVF. They can lose a large amount of blood in a short period of time if not treated promptly, but if treated too aggressively clotting may occur in the AVF.

Nurses can give patients some tips on how to control the bleeding if the needle sites begin to bleed again after dialysis (this can happen occasionally):

• Make sure the patient applies pressure directly on to the needle site in the same way when as needle removal

• Advise them to keep applying pressure for at least 5 minutes before checking to see if the bleeding has stopped. If it has, apply a new plaster. If it continues to bleed, apply pressure again until it stops

• Tell them to contact the dialysis clinic for advice if it continues to bleed after 30 minutes; the patient may need to be seen at their local dialysis unit for assessment


141

Signs of a non-functioning Arteriovenous FistulaPatients should notify the dialysis unit immediately if:

• The AVF stops buzzing, or if the buzzing is faint, as the fistula will need immediate attention. Advise the patient that an admission and possibly surgery may be necessary

• The appearance or feel of the AVF, skin or arm alters. For example, damaged skin, any abnormal lumps, swollen or painful area, and altered sensation in the arm.

• The AVF has been injured. For example, if the patient receives a blow to the AVF, which could cause serious damage, he/she should check the AVF for swelling, bruising and any altered sensation in the arm and that it is still buzzing as normal

In conclusion, patient education/information requires energy and time from the nursing staff, but once the basics for teaching patients are established, morbidity and mortality can only improve.

From Empiric Evaluation to Clinical Research Evidence

143

143


144144

13 From empiric evaluation to clinical research evidence“Hemodialysis patient survival is dependent on the availability of a reliable vascular access. In clinical practice, procedures for vascular access cannulation vary from clinic to clinic. We investigated the impact of cannulation technique on arteriovenous fistula and graft survival. Based on an April 2009 cross-sectional survey of vascular access cannulation practices in 171 dialysis units, a cohort of patients with corresponding vascular access survival information was selected for follow-up ending March 2012. Of the 10,807 patients enrolled in the original survey, access survival data were available for 7058 patients from nine countries. Of these, 90.6% had an arteriovenous fistula and 9.4% arteriovenous graft. Access needling was by area technique for 65.8%, rope-ladder for 28.2%, and buttonhole for 6%. The most common direction of puncture was antegrade with bevel up (43.1%). A Cox regression model was applied, adjusted for within-country effects, and defining as events the need for creation of a new vascular access. Area cannulation was associated with a significantly higher risk of access failure than rope-ladder or buttonhole. Retrograde direction of the arterial needle with bevel down was also associated with an increased failure risk. Patient application of pressure during cannulation appeared more favorable for vascular access longevity than not applying pressure or using a tourniquet. The higher risk of failure associated with venous pressures under 100 or over 150 mmHg should open a discussion on limits currently considered acceptable”.50

The characteristics of the 7058/10807 (65%) patients enrolled in the survey for whom access survival data were obtained are shown in Table 8.


145

Table 8. Patient characteristics for whom access survival were available

Characteristic Value

Mean age, years 63.5 ± 15.0

Female, % 38.5

Diabetic, % 27.1

Native fistula, % 90.6

Graft, % 9.4

Median dialysis vintage, months 43.2

Lower arm access location, % 51.2

Antiaggregant treatment during follow-up, % 51.1

15-G needle size, % 63.7

16-G needle size, % 32.2

Cannulation technique, %

Area puncture 65.8

Rope-ladder 28.2

Buttonhole 6.0

Antegrade direction of arterial puncture, % 57.3

Upward bevel orientation of needle, % 70.2

Needle rotated during insertion, % 42.0

Median blood flow, mL/min 350–400


146146

Tabl

e 9.

Res

ults

of t

he C

ox m

odel

with

prim

ary

outc

ome

vasc

ular

acc

ess

surv

ival

Para

met

erCa

tego

ryRe

fere

nce

HR95

% C

Ip

valu

eM

argi

nal

p va

lue

Age

18-5

0 ye

ars

65-7

6 ye

ars

>75

year

s

50-6

5 ye

ars

1.01

1.03

1.45

0.86

0.89

1.26

1.19

1.18

1.67

0.91

0.

72

<0.0

001

<0.0

001

Gend

erM

aleFe

male

0.93

0.84

1.04

0.21

Diab

etes

Yes

No1.

121.

001.

260.

06

Hear

t fail

ure

Yes

No1.

391.

121.

720.

003

Vint

age

6-24

mon

ths

≥24

mon

ths

unkn

own

0-6

mon

ths

1.04

0.

98

0.55

0.81

0.

77

0.26

1.33

1.

24

1.18

0.79

0.

84

0.13

0.34

Plat

elet a

nti-

aggr

egat

ionYe

sNo

1.11

1.00

1.24

0.05

Fistu

la typ

eGr

aft

Fistu

la1.

741.

482.

06<0

.000

1

AV-fi

stula

locat

ionRi

ght

Left

1.13

1.01

1.27

0.03


147

Para

met

erCa

tego

ryRe

fere

nce

HR95

% C

Ip

valu

eM

argi

nal

p va

lue

AV-fi

stula

locat

ionPr

oxim

alDi

stal

1.49

1.33

1.67

<0.0

001

Need

le siz

e14

G

16 G

17

G15

G1.

25

1.21

1.

42

0.85

1.

07

0.93

1.83

1.

38

2.17

0.26

0.

003

0.11

0.01

Cann

ulatio

n te

chniq

ueBu

ttonh

ole

Rope

-Lad

der

Area

0.78

0.

890.

61

0.79

1.00

1.

000.

05

0.06

0.04

Beve

l and

nee

dle

direc

tion

Ante

grad

e +

Beve

l Do

wn

Retro

grad

e +

Beve

l Up

Retro

grad

e +

Beve

l Do

wn

Ante

grad

e +

Beve

l Up

0.97

0.

93

1.18

0.82

0.

81

1.01

1.14

1.

07

1.37

0.71

0.

32

0.04

0.03


148148

Para

met

erCa

tego

ryRe

fere

nce

HR95

% C

Ip

valu

eM

argi

nal

p va

lue

Bloo

d flo

w<3

00 m

L/m

in 35

0-40

0 m

L/m

in >4

00 m

L/m

in

300-

350

mL/

min

1.18

0.

91

0.93

1.01

0.

80

0.75

1.36

1.

04

1.15

0.03

0.

16

0.49

0.03

Veno

us p

ress

ure

<100

mm

Hg

150-

200

mm

Hg

200-

300

mm

Hg

>300

mm

Hg

100-

150

mm

Hg

1.51

1.40

1.87

2.09

1.11

1.20

1.54

1.21

2.07

1.64

2.26

3.59

0.00

9 <0

.000

1 <0

.000

1 0.

008

<0.0

001

Arm

com

pres

sion

at

time

of ca

nnula

tion

None

To

urniq

uet

Patie

nt

assis

tanc

e1.

25

1.30

1.04

1.

071.

49

1.58

0.02

0.

008

0.02

Abb

revi

atio

ns: C

I, C

onfid

ence

Inte

rval

; HR

, Haz

ard

Rat

io.1


149

13.1 Recommendations for best cannulation practiceIn summary, this study revealed that area cannulation technique, despite being the most commonly used technique, was inferior to both rope-ladder and buttonhole for the maintenance of VA functionality.

However, when choosing a cannulation technique, other aspects need to be considered: patients’ characteristics, staff experience, centre organisation, shift planning, etc. The buttonhole cannulation technique requires specific expertise, excellent centre organisation and, above all, a strict respect of hygienic rules. Buttonhole cannulation does not allow for any margin of error.

For the above reasons, the rope-ladder technique should be the first choice. It provides almost the same results in terms of fistula survival as the buttonhole, and requires fewer pre-requisites to be successful. There are few exceptions which indicate the buttonhole cannulation as the absolute best option: when there is a limited area for cannulation sites and for the potential self-care dialysis patient.

With regard to the effect of needle and bevel direction, the combination of antegrade positioning of the arterial needle with bevel-up orientation was significantly associated with better access survival than retrograde positioning with bevel down. However, it seems that the arterial needle direction has a higher impact on AVF survival than the bevel direction.

Results referring to the type and location of access and the technical parameters (i.e., venous pressure) were as follows: there was an increased risk for access failure for grafts vs fistulae, proximal location vs distal, right arm vs left arm, and for the presence of a venous pressure >150 mmHg vs pressures between 100 and 150 mmHg.


150150

The results on venous pressure are worth considering. A venous pressure of 200–250 mmHg is considered acceptable by the scientific community; the results of this study put these values under discussion. Further investigations are required to clarify the topic fully.


151

Conclusions

153

153


154154

13 Conclusions The AVF is recognised worldwide as the ‘gold standard for VA’; however, care and management of this VA is not without its challenges. Both the haemodialysis nurse and patient have an important role in ensuring the longevity of the AVF. The haemodialysis nurse needs to develop expertise in the assessment of VA and be vigilant for any indications of possible complications.36

A good knowledge is necessary to enable the nurse to assess, plan, implement and evaluate the care given to patients before, during and after cannulation of the AVF and to deal with complications of the VA.

Proper cannulation is crucial for the long-term survival of VA and is a fundamental skill that the nurse must develop. First cannulation of VA should be carried out by a nurse who is an expert in the art of cannulation. The first cannulation is also an important opportunity for the expert nurse to demonstrate and transfer his/her knowledge and expertise to novice cannulators. This will ensure the continuing education of healthcare staff engaged in patient care within the haemodialysis unit.36

Haemodialysis patients have a role to play and must be educated on the care and management of their VA and have knowledge of how to deal with any VA emergencies that might arise within their own home environment.36

Conclusions

155

Appendix

157

157


158158

14 Appendix

14.1 Table of abbreviations

A Arterial Blood sample

ANNA American Nephrology Nurses Association

AV Arteriovenous

AVF Arteriovenous Fistula

AVG Arteriovenous Graft

BTM Blood temperature monitor

CARI Caring for Australasians with Renal Impairment

CE-MRA contrast-enhanced magnetic resonance angiography

CHF Congestive Heart Failure

CKD Chronic Kidney Disease

CVC Central Venous Catheter

DD In-line Dialysis

DDU Duplex Doppler Ultrasound

DRIL distal revascularisation-interval ligation

DVP Dynamic Venous Pressure

eKt/V equilibrated Kt/V

ERBP European Renal Best Practice Guidelines

ESA Erythropoetin Stimulating Agent

ESRD End Stage Renal Disease

GFR Glomerural Filtration Rate

GPT Glucose Pump infusion Technique

Appendix

159

HCAI Healthcare Associated Infections

HCW Healthcare Workers

HDM haemodynamic monitor

IAP Intra Access Pressure

KDOQI Kidney Disease Outcome Quality Initiative

Kt/V Dialysis adequacy

LV left ventricular

LVEDV left ventricular end diastolic pressure

MR Magnetic Resonance

MRA Magnetic Resonance Angiography

PPE Personal protective equipment

PTFE polytetrafluoroethylene

PVD Peripheral Vascular Disease

RA Renal Association (RA) guidelines

RN Registered Nurse

RRT Renal Replacement Therapy

S Systemic arterial sample

S. aureus Staphylococcus aureus

14.2 Bibliography

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2. Konner K. (2003). The initial creation of native arteriovenous fistulas: surgical aspects and their impact on the practice of nephrology. Semin Dial 16, 291–298


160160

3. National Kidney Foundation. Clinical practice guidelines for vascular access, NKF KDOQI. 2006

4. Tordoir J, Canaud B, Haage P et al. (2007). EBPG on vascular access. Nephrol Dial Transplant 22(suppl 2), ii88–ii117

5. Counts CS (ed). Core curriculum for nephrology nursing. 5th ed. Pitman, NJ: American Nephrology Nurses’ Association, 2008

6. Reinhold C, Haage P, Hollenbeck M et al. (2011). Multidisciplinary management of vascular access for haemodialysis: from the preparation of initial access to the treatment of stenosis and thrombosis. Vasa 40, 188–198

7. Beathard GA, Peden EK. (2012). Creating an arteriovenous fistula for haemodialysis

8. Achneck HE, Sileshi B, Li M et al. (2010). Surgical aspects and biological considerations of arteriovenous fistula placement. Semin Dial 23, 25–33

9. Nates RA, Alonso RP. (2012). Manual de Enfermería Nefrológica. Madrid: Pulso Ediciones

10. Mc Cann Μ, Einarsdottir H, Van Waeleghem JP et al. (2008). Vascular access management I: An overview. J Renal Care 35(2), 90–98

11. UK Renal Association. (2008–2011) Clinical Practice Guidelines. Vascular Access for Haemodialysis. Complications of vascular access (Guidelines 6.1–6.4) 5th edition

12. Dougherty L, Lister S (eds). (2011). The Royal Marsden Hospital Manual of Clinical Nursing Procedures. Marsh.

13. World Health Organization. (2009). WHO Guidelines on Hand Hygiene in Health Care. Geneva: World Health Organization

14. Centers for Disease Control and Prevention (CDC). (2007). Invasive methicillin-resistant Staphylococcus aureus infections among dialysis patients – United States, 2005. Morb Mortal Wkly Rep 56, 197

15. Fan PY, Schwab SJ. (1992). Vascular access: concepts for the 1990s. J Am Soc Nephrol 3,1

16. Anderson JE, Chang AS, Anstadt MP. (2000). Polytetrafluoroethylene hemoaccess site infections. ASAIO J 46, S18

17. Verhallen AM, Kooistra MP, van Jaarsfeld BC. (2007). Cannulating in hemodialysis: rope-ladder or buttonhole technique? Nephrol Dial Transplant 22(9), 2601–2604

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18. Van Loon M, Goovaerts T, Kessel A, et al. (2010). Buttonhole needling of hemodialysis arteriovenous fistulae results in less complications and interventions compared to the rope-ladder

19. Chow J, Rayment G, San Miguel S, Gilbert M. (2011). A randomized controlled trial of buttonhole cannulation for the prevention of fistula access complications. J Renal Care 37(2); 85–93

20. Challinor P. (2008). Haemodialysis in renal nursing. 3rd ed. Thomas N. Bailliere Tindall, 3rd ed. pp 181–222.

21. Kaufman J. (2008). Major complications from vascular access for chronic hemodialysis. In: Nissenson A, Fine R (eds). Handbook of Dialysis Therapy. 4th ed. Philadelphia, PA: Saunders-Elsevier

22. Vogel S. (1993). Access to bloodstream. In: Gutch C, Stoner M, Corea A (eds). Review of Heamodialysis for nurses and dialysis personnel. 5th ed. St Louis, MI: Mosby. pp 110–125

23. Besarab A, Raja R. (2001). Vascular access for hemodialysis. In Daugirdas J, Blake P, Ing T (eds). Handbook of Dialysis. 3rd ed. Philadelphia PA: Lipincott Williams & Wilkins

24. Ball LK. (2005). Improving arteriovenous fistula cannulation skills. Nephrol Nurs J 32(6), 611–617

25. Doss S, Schiller B,Moran J. (2008). Buttonhole cannulation—an unexpected outcome. Nephrol 32, 44

26. Mc Cann Μ, Einarsdottir H, Van Waeleghem JPet al. (2009). Vascular access management II: AVF/AVG cannulation techniques and complications. J Renal Care 35(2), 90–98

27. Levy J, Morgan J, Brown E. (2005). Screening for arteriovenous fistula/graft stenosis and thrombosis. In: Oxford Handbook of Dialysis 2nd ed. Oxford, UK: Oxford University Press

28. Tordoir JH, Herman JM, Kwan TS, Diderich PM. (1988). Long-term follow-up of the polytetrafluoroethylene (PTFE) prosthesis as an arteriovenous fistula for haemodialysis. Eur J Vasc Surg 2(1), 3–7

29. Nesrallah G. Cuerden M, Wong JHS. (2010). Staphylococcus aureus bacteremia and buttonhole cannulation: long-term safety and efficacy of mupirocin prophylaxis. Clin J Am Soc Nephrol 5(6), 1047–1053

30. Beathard G. (2002). Physical diagnosis of the dialysis vascular access. In: Dialysis Access: A Multidisciplinary Approach. Gray JR, Sands JJ (eds). Philadelphia, PA: Lippincott Williams & Wilkins. pp 111–118


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31. Rocek M, Peregrin J. (2001). Percutaneous interventions for vascular dialysis access. EDTNA ERCA J 27(2), 83, 91.

32. Turmel-Rodrigues L, Pengloan J, Rodrigue H et al. (2000). Treatment of failed native arteriovenous fistulae for hemodialysis by interventional radiology. Kidney Int 57(3), 1124–1140

33. Besarab A, Hall B, El-Ajel F et al. (1995). The relation of brachial artery flow to access flow. J Am Soc Nephrol 6, 483A

34. Safa A, Valji K, Roberts A, et al. (1996). Detection and treatment of dysfunctional hemodialysis access grafts: Effect of a surveillance program on graft patency and the incidence of thrombosis. Radiology 199, 653–657

35. Vaux E, King J, Lloyd S, et al. (2013). Effect of buttonhole cannulation with a polycarbonate peg on in-center haemodialysis fistula outcomes: a randomized controlled trial. Am J Kidney Dis 62, 81–88

36. Nassar GM, Ayus JC. (2000). Clotted arteriovenous grafts: a silent source of infection. Semin Dial 13, 1

37. Nassar GM, Ayus JC. (2002). Infectious complications of old nonfunctioning arteriovenous grafts in renal transplant recipients: a case series. Am J Kidney Dis 40, 832

38. Stern AB, Klemmer PJ. (2011) High-output heart failure secondary to arteriovenous fistula. Hemodial Int Jan doi: 10.1111/j.1542-4758.2010.00518.x

39. Murphy S, Parfrey P. (2008). Management of ischemic heart disease, heart failure, and pericarditis in haemodialysis patients. In: Nissenson A, Fine R (eds). Handbook of Dialysis Therapy. 4th ed. Philadelphia, PA: Saunders-Elsevier

40. Krönung G. (1984). Plastic deformation of Cimino fistula by repeated puncture. Dial Transplant 13, 635–638

41. Nicola Tessitore et al. (2011). In Search of an Optimal Bedside Screening Program for Arteriovenous Fistula Stenosis. Clin J Am Soc Nephrol 6(4), 819–826

42. Schneditz D, Wang E, Levin N. (1999). Validation of haemodialysis recirculation and access blood flow measured by thermodilution. Nephrol Dial Transplant 14, 376–383

43. Daugirdas J, Blake P, Ing T. (2007). Arteriovenous access for haemodialysis. In: Handbook of Dialysis. 4th edition. Philadelphia, PA: Lippincott Williams & Wilkins

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44. Wasinrat J, Siriapisith T, Thamtorawat S, Tongdee T. (2011). 64-slice MDCT angiography of upper extremity in assessment of native hemodialysis access. Vasc Endovascular Surg 45, 69–77

45. Fistula First. Cannulation of the AV fistula. Available at: http://www.fistulafirst.org/HealthcareProfessionals/WheredoIstartifIamadialysiscenter/CannulationoftheAVFistula

46. Miller CD, Robbin ML, Allon M. (2003). Gender differences in outcomes of arteriovenous fistulas in hemodialysis patients. Kidney Int 63(1), 346–352

47. Hawkins C. (1995). Nurses’ roles in influencing positive vascular access outcome. ANNA J 22(2), 127–129

48. Fluck R, Kumwenda M. (2011). Renal Association clinical practice guideline on vascular access for haemodialysis. Nephron Clin Pract 118(suppl 1), c225–c240

49. Besarab A, Sullivan L, Ross R, Moritz M. (1995). Utility of intra-access pressure monitoring in detecting and correcting venous outflow stenosis prior to thrombosis. Kidney Int 47, 1364–1373

50. Parisotto MT et al. (2014). Cannulation technique influences arteriovenous fistula and graft survival. Kidney Int doi: 10.1038/ki.2014.96

Index

165

165


166166

15 Index

Title PageAAccess flow 53, 100, 101, 105, 112,

114, 115, 127Allen Test 107Anastomosis 35, 47, 49, 50, 53, 70,

94, 99, 100, 101, 107, 122

Aneurysm 68, 75, 76, 77, 80, 82, 83, 84, 91, 92, 93, 98, 101, 103, 104, 121, 129

Antegrade 72, 77, 78, 85, 144, 145, 147, 149

Anticoagulant 43, 66, 102, 103Atherosclerotic 43Area 24, 29, 34, 53, 59, 66,

75, 78, 83, 84, 85, 91, 93, 94, 101, 103, 104, 120, 129, 135, 138, 141, 144, 145, 147, 149

Arterial 42, 43, 47, 50, 51, 53, 71, 72, 75, 76, 77, 78, 79, 85, 87, 92, 98, 99, 100, 101, 106, 107, 108, 112, 113, 114, 122, 124, 125, 128, 134, 144, 145, 149

Index

167

Arteriovenous Fistula 18, 24, 28, 30, 38, 39, 42, 43, 48, 53, 54, 64, 68, 69, 90, 98, 105, 112, 114, 118, 132, 133, 134, 135, 138, 141, 144

Arteriovenous Graft 28, 30, 38, 39, 144Artery 34, 35, 42, 43, 46, 49,

50, 51, 54, 106, 107, 108,

Auscultation 53, 68, 69BBevel 73, 77, 78, 82, 144,

145, 147, 149, Bleeding 43, 68, 80, 81, 82, 83,

84, 87, 88, 92, 100, 104, 120, 121, 123, 127, 140

Blood flow 19, 28, 29, 35, 43, 44, 49, 51, 52, 64, 67, 71, 72, 77, 82, 85, 88, 89, 92, 99, 100, 101, 106, 107, 112, 113, 122, 123, 124, 125, 129, 137, 138, 139, 145, 148

Blood flow rate 29, 67, 113, 125 Blood pressure 102, 135, 138Blood pump 99, 113, 128Body fluids 58, 60, 61Body image 84


168168

Bruit 28, 53, 68, 99, 102, 119, 137

Buttonhole 70, 75, 79, 81, 82, 83, 93, 95, 101, 144, 145, 147, 149

C

Cannulation techniques 25, 28, 30, 64, 75, 118

Cannulation sites 76, 81, 90, 127, 138, 149

Cardiac 44, 105

Central Venous Catheter 28, 30, 38, 39

Chronic Kidney Disease (CKD) 42, 43, 48, 52, 132, 134

Complications 18, 24, 25, 28, 29, 30, 43, 52, 64, 65, 68, 79, 80, 90, 92, 98, 105, 112, 119, 121, 127, 138, 154

E

End Stage Renal Disease 18, 24, 42

European Renal Best Practice (ERBP) 52

Evaluation 43, 44, 52, 92, 94, 112, 114, 144

Exercises 135

F

Fever 54, 139

G

Index

169

Glomerular Filtration Rate (GFR) 42, 43H

Haemodialysis 18, 19, 20, 24, 25, 28, 34, 35, 38, 42, 43, 65, 90, 93, 94, 100, 101, 102, 107, 118, 124, 126, 127, 133, 154

Haematoma 68, 78, 85, 86, 87, 90, 91, 93, 94, 99, 102, 120, 139

Hyperaemia 107

Hypertension 35, 49, 53

Hypertrophy 51, 105

Hypoperfusion 107

Hypopulsation 119

Hypotension 101, 139, 140

IInfection 18, 24, 25, 28, 30, 38,

44, 54, 58, 59, 60, 69, 76, 80, 90, 92, 93, 94, 95, 99, 101, 104, 121, 135, 138, 139,

Infiltration 51, 74, 78, 80, 85, 90, 91, 120

MMagnetic Resonance 55, 115Maturation 18, 42, 51, 52, 53, 54,

99, 118, 119, 135


170170

Monitoring 18, 54, 68, 100, 102, 111, 112, 118, 122, 123, 126, 127, 129

NNeedles 19, 20, 34, 44, 66, 70,

71, 77, 82, 85, 86Needle removal 30, 86, 89, 100, 104,

120, 123, 127, 140Needle rotation 74Needle tips 75, 127PPain 24, 72, 76, 80, 83, 90,

92, 93, 100, 106, 107, 123, 124, 134, 139

Patient education 30, 64, 132, 133, 141Peritoneal dialysis 44, 133Physical examination 44, 68, 93, 100, 107,

124, 127Pseudo-aneurysm 68, 84, 91, 92, 93, 98,

104Pulse 54, 68, 89, 100, 102,

106, 107, 119, 121, 122RRecirculation 54, 100, 113, 114, 125,

127Retrograde 72, 77, 78, 85, 144,

147, 149Rope Ladder 75, 76, 78, 93, 145,

147, 149

Index

171

SSteal Syndrome 18, 35, 106, 107, 108,

124Stenosis 43, 52, 53, 54, 58, 84,

88, 98, 99, 100, 101, 104, 112, 113, 114, 120, 121, 122, 123, 128

TThermodilution 113Thrill 53, 54, 68, 88, 89, 99,

100, 102, 114, 119, 121, 122, 135, 137

Thrombosis 28, 38, 50, 58, 101, 102, 103, 114, 118, 120, 122, 123, 128, 129, 139

UUrea Reduction Ratio (URR) 114VVein 44, 45, 47, 48, 52, 54,

102, 123, 128, 134Venous 28, 30, 35, 38, 39, 44,

47, 49, 50, 51, 53, 54, 71, 76, 77, 79, 85, 87, 88, 89, 98, 99, 100, 101, 104, 112, 113, 114, 123, 128, 144, 148, 149, 150,

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