WREXHAM ANAESTHETIC DEPARTMENT TEACHING

DAVID GEORGE

ARTERIAL AND CVP WAVEFORM

OBJECTIVES‣ PRINCIPLES

‣ INDICATIONS

‣ COMPONENTS

‣ WAVEFORMS

‣ QUESTIONS

ARTERIAL AND CVP TRACE 31/8/17

PRINCIPLES▸ Intravascular pressures measurement

▸ Intravascular Cather connected via a fluid filled tubing to a transducer

▸ Resonance

▸ Tendency of a system to oscillate at maximum amplitude at a particular frequency

▸ Dampening

▸ Reduces the amplitude of oscillations in an oscillating system

▸ Zeroing

▸ Measurement is referenced to a point, the RA, which is then set as zero pressure

ARTERIAL AND CVP TRACE 31/8/17

INDICATIONS-ARTERIAL LINE

▸ Blood pressure

▸ Beat to beat

▸ Ineffective NIBP

▸ Where BP is being manipulated

▸ Sampling

▸ CO monitoring

▸ Access to vascular system e.g. angiography, intra-arterial thrombosis

▸ Heart Rate

▸ Pressure

▸ Systolic function

▸ Filling

▸ Pulse contour analysis

LOCATION‣ RADIAL ‣ BRACHIAL ‣ FEMORAL ‣ DORSALIS PEDIS ‣ POSTERIOR TIBIAL

ARTERIAL AND CVP TRACE 31/8/17

COMPONENTS▸ Arterial cannula

▸ Fluid filled stiff tubing

▸ Ports

▸ Transducer

▸ Pressure bag 300mmHg

▸ Computer

ARTERIAL AND CVP TRACE 31/8/17

COMPLICATIONS▸ Technical

▸ Disconnection

▸ Inadvertent intra-arterial injection

▸ Catheter fracture/Wire loss

▸ Incorrect flush solution

▸ Insertion difficulties

▸ Medical

▸ Thrombosis/embolism

▸ Ischaemia

▸ Haematoma/False aneurism

▸ Infection

▸ Damage to local structures

▸ Stenosis

▸ Ateriovenous fistular

ARTERIAL AND CVP TRACE 31/8/17

WAVEFORM

▸ Upstroke - contractility

▸ Peak - Systolic

▸ Dicrotic notch

▸ Downstroke

▸ AUC

WHERE?AS PRESSURE WAVE TRAVELS DISTAL ‣ ARTERIAL UPSTROKE

BECOMES STEEPER ‣ SYSTOLIC PEAK INCREASES ‣ DICROTIC NOTCH APPEARS

LATER ‣ DIASTOLIC PRESSURE LOWER ‣ MAP SLIGHTLY HIGHER IN

AORTA ‣ DELAY IN PRESSURE WAVE

QUIZANACROTIC - AORTIC STENOSIS

COLLAPSING - HYPERDYNAMIC

BISFERIENS - AS AND AR

ALTERNANS LVF

DAMPED TRACE

RESONANCE - TOO LONG OR TOO FLEXIBLE

CATHETERA-Z Anaesthesia and intensive care

SWINGVARIATIONS WITH RESPIRATION

USE IN THOSE ON IPPV

NOT USEFUL IN SPONTANEOUSLY BREATHING

INDICATES VARIABLE FILLING

COLLAPSE OF IVC/SVC WITH RISING INTRATHROACIC PRESSURE

https://www.slideshare.net/samirelansary/arterial-line-analysis-46584416

CENTRAL VENOUS PRESSURE

ARTERIAL AND CVP TRACE 31/8/17

CENTRAL VENOUS

▸ A Wave

▸ C Wave

▸ V Wave

▸ X Decent

▸ Y Decent

▸ Filling

TEXT

RAISED CVP

▸ Right ventricular failure

▸ Fluid Overload

▸ High PEEP

▸ Hyperdynamic circulation

▸ Tricuspid stenosis/TR

▸ Pericardial effusion/Pericarditis

▸ SVC obstruction

WikiEcho.org

TEXT

WAVEFORM ANALYSIS

▸ Dominant A wave - Pulmonary Hypertension

▸ Cannon A wave - Complete heart block

▸ Dominant V wave - TR

▸ Absent X descent - AF

▸ Exagerated X descent - Tamponade, constrictive pericarditis

▸ Sharp Y descent - TR, Atrial Myxoma

▸ Prominent x and y descent -RV infarction

ARTERIAL AND CVP TRACE 31/8/17

MCQ

▸ Which of the following are correct

1. Normal saline is used for arterial line flush

2. 5% Dextrose is a suitable flush for CVP lines

3. A pressure of 200mmHg is suitable for flush line

4. A flow rate of 0.4ml/hr through an arterial is suitable

5. Non-injectable ports are not suitable for arterial lines

TEXT

MCQ

▸ In relation to pressure transduction lines

1. Highly compliant sets reduce damping

2. Highly rigid sets increase accuracy

3. An optimum damping ratio is 0.54

4. Transducer lines are made of latex

5. IV fluid giving sets are a suitable alternative

TEXT

MCQ

▸ In relation to central venous pressure waveform

1. Cannon v waves are seen in complete heart block

2. CVP is the ‘Gold Standard’ fluid guide

3. Cardiac tamponade may give a high CVP

4. Raising PEEP with raise CVP in a ventilated patient

5. An arterial trace is seen on the monitor after insertion of a CVP, this means the tip is in the RV and needs to be pulled back to be used safely

TEXT

SAQ

▸ List indictions for invasive blood pressure monitoring

▸ Describe the information that may be obtained from an arterial pressure waveform

ITS BETTER TO BE LUCKY THAN SKILLED

Dave 2017

TEXT

TEXT

▸ E-Learning for health Core training, 03_02_01 Indications and Complications of Arterial Lines

▸ CEACCP - https://doi.org/10.1093/bjaceaccp/mkt078

▸ ATOW - Physical principles of intra-arterial blood pressure measurement 2009

▸ A-Z anaesthethesia and critical care

▸ Training in anaesthesia, The essential curriculum

▸ WikiEcho.org

References and Further Reading