approach to diabetic foot

THE DIABETIC FOOT

APPROACH to DIABETIC FOOT

Dr. Faiez Alhmoud Surgery Dpt.

Albashir Hospital(MOH)

Diabetic Foot (DF)

It will be unwise if we restrict the term (DF) to foot infection, ulcer or gangrene in a diabetic patient

Why? (advanced stage of the disease)

Diabetic foot definition

Diabetic foot is a disease complex that can develop in the skin, muscles, or bones of the foot as a result of the nerve damage, poor circulation and/or infection that is associated with diabetes.

The Diabetic Foot may be defined as a syndrome in which neuropathy, angiopathy, and infection will lead to tissue breakdown resulting in morbidity and possible amputation ( WHO 1995 )

Any foot pathology that result from diabetes or it’s long – term results (Boulton 2002)

Epidemiology and facts 15% of the adult population in Jordan are diabetics 15% of those with diabetes will, develop an ulcer 15% of patients develop osteomyelitis & 15%

amputation 80% of foot ulcers are precipitated by external

trauma 20% of diabetics admitted to hospitals because of

foot problems Cellulitis occurs 10 times more frequently in diabetics Osteomyelitis of the foot 15 times more frequently in

diabetics than non-diabetics Diabetic patients are 15x at risk of BKA Nearly half of non-traumatic LLA caused by diabetes. 70% of lower limb amputations begin with a foot

ulcer ~50% of diabetics with LLA require 2nd LLA within 5

years 5 year survival rate ~50% after BKA--Tragic “Rule of

50” The annual direct and indirect costs is high Up to 85% of amputations can be avoided.

Diabetic foot…..facts

Every 30 seconds a lower limb is lost somewhere in the world as a consequence of diabetes

Diabetic foot infection require attention to local (foot) and systemic (metabolic) issues by multidisciplinary foot care team

Only in the last 20 years progress in the understanding of pathogenesis and management of diabetic foot had been made

However …. there is still gap between what’s known about diabetic foot and what’s really done to them

Natural history of diabetic foot

It’s unwise to consider that major diabetic foot problem occur all of sudden

There is high risk foot which means There are1- Predisposing factors (Neuro- and angiopathy) العوامل

المهيئة2- Precipitating factors (Trauma and tinea) العوامل المعجلة 3- Perpetuating factors (Pt’s factors & delay healing)

عوامل التكريس

What’s the high risk foot ?

Long duration and uncontrolled D.M …Plus one or more:

Peripheral neuropathy Peripheral vascular disease Trauma Previous ulcers Diabetic nephropathy or retinopathy Obesity Lack of education Male gender ??!!

FOOT AT RISK

Pathophysiology

The critical triad of :1- Neuropathy2- Foot deformity &3- Trauma ……………

will lead to ulcer

The presentation in the majority of pts is an infected ulcer!!

Neuropathy

Sensory : lack of protective sensation (unrecognized trauma)

Motor : Change in foot anatomy (Pressure points) & altered gait and deformity

Autonomic : Lack of sweat ( dry & cracked skin )

Neuropathy

The Gift of Pain

“Pain: The gift nobody wants “.

Paul Brand

Classification and definition of problem

The neuropathic foot – in which

neuropathy predominates but the major

arterial supply to the foot is intact.

The neuro-ischaemic foot – where

neuropathy, and ischaemia resulting from

a reduced arterial supply, contribute to

the clinical presentation.

Infection - is rarely the only factor

but often complicates neuropathy and or

ischaemia, and is responsible for considerable tissue necrosis

Stages Of Ulcer Development

Assessment

History Physical examinations Investigations Patient Limb or foot Wound

Who will take care ?

G. Physicians General Surgeons Diabetologists (Endocrinologist) Orthopaedic surgeon Vascular surgeon Plastic surgeon Podiatrists Specialised nurse

Assessment………..History

Generally: fever, chills, sweats, vom…

Condition : confused, depressed…. Socially : neglected, lack of home

sup Neuropathy : Numbness, loss of

sens. burning, tingling, numbness &

nocturnal leg pains.  Others : duration, diabetic control,

previous ulceration, smoking, HTN....

Assessment………Clinical Ex.

What to look for ? V.S : tachycardia, hypotension… Signs of volume depletion Cognitive state:delirium,stupor, coma Limb-Foot: 1- Biomechnics: deformities, change pressure points2- Vascular status ( arterial, venous, ABI, ischemia,

gangrene…3- Neuropathy ( light touch, vibration, monofilament

pressure 4- Examining the feet for structural abnormalities such

as nails, calluses, hammer toes, claw toes and flat foot

Diabetic Foot Examination

D deformity I infection A atrophic nails B breakdown of skin E oedema T temperature I ischemia C callosities S skin colour

Assessment………Clinical Ex.

Typical neuropathic foot

Neurologic assessment

Temperature Vibration Sense Pressure Sense Light Touch Proprioception (Romberg’s Sign) Superficial Pain Reflexes

Nylon monofilament test

Neuropathy

Charcot foot“Acute or subacute inflammation of all

or part of the foot in people with diabetes complicated by distal symmetrical neuropathy, accompanying fracture or dislocation that cannot be explained by recent trauma, and with or without preceding ulceration of the surrounding skin”

(Jeffcoate 2004)

Diagnosis of Acute Charcot

Painless

Redness, swelling, and more than 2°C skin temperature difference when compared with the contralateral foot.

Dorsalis pedis pulses are often

bounding.

The patient is afebrile unless a systemic infection is present.

Ulcer assessment

1. Site, size and shape2. Edges3. Establish its depth and involvement of deep

structures4. Examine it for purulent exudates, necrosis,

sinus tracts, and odor5. Assess the surrounding tissue for signs of

edema, cellulitis, abscess, and fluctuation6. Perform a vascular evaluation. 7. The ability to gently probe through the ulcer

to bone has been shown to be highly predictive of osteomyelitis.

8. Establish the ulcer's etiology9. Exclude systemic infection

Classification of diabetic foot ulcer

Wagner Grading System Grade 0 skin intact but "foot at risk" Grade 1: Superficial Diabetic Ulcer &

localised Grade 2: Deep ulcer & extension

Involves ligament, tendon, joint capsule or fascia

No abscess or Osteomyelitis Grade 3: Deep ulcer with abscess or 

Osteomyelitis Grade 4: Gangrene to portion of forefoot Grade 5: Extensive gangrene of entire foot

Classification of diabetic foot ulcer

Neuropathic foot ulcer.

Khanolkar M et al. QJM 2008;101:685-695

© The Author 2008. Published by Oxford University Press on behalf of the Association of Physicians. All rights reserved. For Permissions, please email:

journals.permissions@oxfordjournals.org

The Charcot foot.

Khanolkar M et al. QJM 2008;101:685-695

© The Author 2008. Published by Oxford University Press on behalf of the Association of Physicians. All rights reserved. For Permissions, please email:

journals.permissions@oxfordjournals.org

Effects of Diabetic Peripheral Neuropathy

Vascular assessment

History Changes in skin Pulses Exercise Testing ABPI Duplex Angiography

Assessment..........Ischemia

Peripheral Vascular DiseaseChronic limb ischaemia

Grade 0 = Mild claudication

Grade 1 = Moderate to severe claudication withouttissue loss or ischaemic rest pain

Critical ischaemia Grade 2 = Ischaemic rest pain

Grade 3 = Tissue loss due to ischaemic ulceration or

gangrene

Vascular assessment .........

...........Ankle Brachial IndexABI value Indicates <0.9 Abnormal 0.8- 0.9 Mild PAD 0.5- 0.8 Moderate PAD <0.5 Severe PAD <0.25 Very Severe PAD******The ABI has limited use in

evaluating calcified vessels that are not compressible as in diabetics (gives reading above one)

Ischaemic foot ulcer.

Khanolkar M et al. QJM 2008;101:685-695

© The Author 2008. Published by Oxford University Press on behalf of the Association of Physicians. All rights reserved. For Permissions, please email:

journals.permissions@oxfordjournals.org

Assessment…….Infection

Infection is diagnosed clinically by

The presence of purulent secretion

OR At least 2 of the cardinal local

manifestations of inflamation Hotness Redness Swelling Function loss or pain

Clinical assessment of infection

Non-Limb-threatening Infections:

Superficial infection

Lack systemic toxicity

Minimal cellulitis (< 2 cm. Extension from portal of entry)

Ulcer-if present-doesnot penetrate fully thru skin

No bone or joint involvement

No underlying ischemia

Clinical assessment of infection

Limb-threatening infections: Extensive cellulitis (> 2 cm.)

Lymphangitis

Full-thickness ulcers

Frequent bone & joint infections

Ischemia + gangrene

Fever +

Deep plantar abscesses

Bacteremia + hematogenous spreading infections

Classification of diabetic foot infection

Minimal inflammation with no pus = 1

2 or more signs or ~2cm erythema around the ulcer or superficial path. and no systemic manifistations = 2

As above plus deeper infection, lymphangitis ,abscess or gangrene =3

As above with systemic or metabolic instability = 4

Classification of diabetic foot infection

Non-Limb-threatening Infections:

Classification of diabetic foot infection

Limb-threatening Infection:

Common Pathogens

MILD infection = MONOMICROBIAL SEVERE infection = POLYMICROBIAL

In acute wounds and cellulitis : S. aur. & B.Hem. Strept. are commonly found (+)

In chronic infected wounds : add entrobacter (-)

Macerated soaked wound : Pseudomonas Long duration & nonhealing : all the above

plus fungi Deep infection & extensive necrosis with

bad odor : all the above plus obligate anaerobes

Principles of diabetic foot ulcer

managementبدها صبر

Five cornerstones of management

of the diabetic foot

The situation can be changed & possibly

reduce amputation rates between 50% -85% by:

1- Regular inspection and examination of the foot and patient education

2- Identification of the foot at risk.3- Education of patient, family and healthcare

providers.4- Appropriate footwear.5- Multidisciplinary approach & treatment of

ulcerative and non-ulcer pathology

Patient education

Decreases the chance of occurrence Foot hygiene Daily inspection Proper footwear Prompt treatment of new lesions

Must take an active role in their care Disease management Routine nail care Ulcer management

Elective surgery to correct structural deformities before ulcerations occur

A multidisciplinary approach

Providing : - Debridement, - Meticulous wound care, - Adequate vascular supply,- Metabolic control, - Antimicrobial treatment and -Relief of pressure (offloading) are

essential in the treatment of foot ulcer.

Investigations

Bloodwork for high BS, DKA, hyperosmolar state…..

Gram staining and culture Imaging- Plain X-ray- MRI ?- Doppler – Angiogram- US? For deep abscess- Doppler and ABI

Approach to foot wound in diabetics

General Principles1- Avoid antibiotics in uninfected foot2- Determine the need for hospitalizationSevere infection or critical ischemia

3- Stabilize the patient and correct:- Fluids and electrolytes - Hyperglycemia, hyperosmolarity ,acidosis- Treat other exacerbating factors4- Choose antibiotic regimen:Limited data support the use of topical antibioticsMild-moderate infection, give narrow spectrum antibiotics –no

anaerobSevere infection, give broad-spectrum with anaerobic

coverage

Principles of Foot ulcer management

1.Infection Control2.Offloading3.Vascular assessment4.Wound care

Infection Control

Foot infections are the most common cause of admission to hospital for patients with diabetes

Infection is a precursor to amputation in many cases

Need to be treated aggressively Sampling by sterile swabs misses important

pathogens True bacteriological yield is obtained from

deep tissue samples IF INFECTION IS PRESENT, DO NOT WAIT

FOR SWAB RESULTS

Approach to foot wound in diabetics

……Principles of wound care1- Determine the need for surgeryRanges from debridement to revascularizationDetermine life- or limb-threatening condition ( NF, GG,

Ischemia…. )

2- Formulate wound care plan- Daily inspection- Dressing and debridement as needed- Removal of pressure…..

3- Twice- weekly follow up for outpatients4- WBC, ESR, C-RP, culture … are of limited

value

Debridement

Sharp

Larval

Enzymatic (Lytic)

Approach to diabetic foot ulcer

According to ulcer stage0 At-risk foot, no ulceration : Patient

education, accommodative footwear, regular clinical examination

1 Superficial ulceration, not infected :Offloading with total contact cast (TCC), walking brace, or special footwear

2 Deep ulceration exposing tendons or joints : Surgical debridement, wound care, offloading, culture-specific antibiotics

3 Extensive ulceration or abscess : Debridement or partial amputation, offloading, culture-specific antibiotics

Approach to ischemic diabetic foot

Ischemia Classification A Not ischemic : no treatmentB Ischemia without gangrene:

Noninvasive vascular testing, vascular consultation if symptomatic

C Partial (forefoot) gangrene :Vascular consultation and debridement

D Complete foot gangrene : Major extremity amputation, vascular consultation

Approach to diabetic foot infection

Antibiotics Empirical antibiotics Benzylpenicillin or ampicillin – Streptococcus sp. Oxacillin, nafcillin or 1 st generation cephalosporin (eg.

cefazolin) – Staphylococcus sp. Quinolone + aminoglycoside (gentamycin) – Pseudomonas

sp. Methicillin-resistant Staphylococcus aureus – vancomycin

or cotri-moxazole Clostridial species are sensitive to a combination of

penicillin G and clindamycin Duration of antibiotic treatment * 1-2 weeks course for mild to moderate infections * more than 2 weeks for more serious infections * 6 - 8weeks for osteomyelitis * If all infected bone is removed,a shorter course (1-2 weeks)

of antibiotics, as for soft tissue infection, may be adequate

Offlaoding

Remove pressure from the affected site is essential

How ?- Footwear- Specialised offloading devices

Offlaoding FootwearGood shoes are integral to good foot

health

Offloading

Vascular assessment

Surgical revascularisation

Follow up

OsteomyelitisConsider potential osteomyelitis in any 1- Deep or extensive chronic ulcer and over bony

prominence2- Unhealed ulcer after 6 weeks of Abx. And offloading

ttt.3- Ulcer in which bone is visible or easily felt4- Sausage toe

Osteomyelitis

Initial screening tool is the plain X-ray : Easily obtained, relatively inexpensive and

provides anatomical information Demineralization, periosteal reaction, bony

destruction: (the classic triad) Appear after 30 – 50% of bone is destroyed

and can take as much as 2 weeks to appear

Found in other conditions such as fracture or deformity

Sensitivity and specificity approximately 54% and 80%

Osteomyelitis

Follow up……Osteomyelitis

DiagnosisSerial X-rays with 2-4 weeks interval- If typical, treat as ostemyelitis- If not but clinically suspected MRI or Bone scan or Radionuclide or Scintigraphic imaging Triple Phase Bone Scan (TPBS) Gallium Scan Indium-111 Leukocyte Scan- Probe to Bone- Empirical antibiotics for 6-8 weeks and repeat Ro or- Bone biopsyMRI is the most accurate imaging modalityThree-phase bone scintigraphy is highly sensitive

Outcome

Good outcome to appropriate therapy

In 80–90% of mild-moderate infection 50-80% of severe or OM infection

Poor outcome associated withSigns of systemic infectionInadequate limb ischemiaOMNecrosis or gangreneProximal site of infectionInexperienced surgeon

Prevention

Early detection of neuropathy Educate patient about- Optimizing glycemic control- Using appropriate footwear- Avoid foot trauma- Perform daily self examination- Smoking cessation

Refer patient with critical ischemia

Key Message Of all late complications of diabetes, foot

problems are the most easily detectable and easily preventable.

Relatively simple interventions can reduce amputations by 50 - 80%. (Bakker et al 1994).

Strategies aimed at preventing foot ulcers are cost effective and cost saving.

“The pathway to amputation Is littered with bandages and dressings

which have deceived both the doctor and patient into thinking that by dressing an ulcer they were curing it”

Diabetics should treat their Feet like their Face

Key Message

Mission:… Happy Feet

QUSTIONS ?