diabetes / diabetic foot / debridement / gangrene /diabetic arteriopathy / peripheral vascular disease

1. Management
of diabetic foot
Dr. Rahul

2. Introduction
– Most common complication of diabetes.
– Greater than retinopathy, nephropathy, heart attack and
stroke combined.
– Most common cause of non traumatic lower limb
amputation.
– 20 times more likely to undergo amputation.

3. Epidemiology
– Leading cause of chronic disease and limb loss worldwide.
– Currently affecting around 382 million people.
– 15% of diabetics will experience foot ulcer at some time over the
course of disease.
– Every year >1 million people with diabetes suffer limb loss as a
result of diabetes.
– Approx. 80% of diabetes related lower extremity amputation are
preceded by foot ulcers.

4. Risk factors

6. Vascular changes
– More than 50% diabetics having the disease for more than 10-15 years are
documented to have atherosclerotic changes.
– Mainly affect arteries below Profunda Femoris and is characterised by multiple
segment involvement.
– Pathogenesis
 Glycosylated LDL enhances formation of cholesteryl esters and accumulation of
macrophages .
 Formation of foam cells.

7. Microangiopathy
– Thickening of basement membranes of small vessels and capillaries.
– Carbohydrates incorporation into BM by induction of enzymes such as glycosyl
and galactosyl transferase.
– Thickening –
 Interferes with transfer of oxygen and nutrients.
 Delays migration of leucocytes.

8. Neuropathy in diabetic foot
– Peripheral neuropathies found in 55% of diabetics.
– Signs and symptoms-
o Hyper or hypoesthesia
o Radicular pain
o Loss of vibratory and position senses
o Heavy callus formation over pressure points
o Changes in bones and joints

9. Neuropathy -Etiology
1. Vascular
• Basement membrane thickening
• Occlusive thrombi
• Epineural vessel atherosclerosis
• Nerve hypoxia
2. Metabolic factors
– Accumulation of sorbitol and glycogen
– Decreased incorporation of glycolipid and amino acid into myelin

10. Natural history
1. Normal: not at risk.
– Does not have risk factors of neuropathy, ischemia,
deformity, callus and swelling.
2. High risk foot: pt. has developed one or more risk factors.
3. Ulcerated foot: foot has a skin breakdown.
4. Infected foot : infection with presence of cellulitis.
5. Necrotic foot
6. Unsalvageable

11. Assessment of diabetic foot
– History
 Medical history
 Foot specific history
– Physical examination
 Dermatologic
 Musculoskeletal
 Neurologic
 Vascular
– Laboratory test and Diagnostic imaging

13. Diagnostic procedures
– Laboratory tests
 Fasting and random blood glucose
 Complete blood count
 Wound and blood cultures
 Urinary analysis
 Common sign of persistent infection is refractory
Hyperglycemia.

14. Imaging studies
– Plain radiograph should be the initial Imaging study
 Can detect osteomyelitis, fractures
 Soft tissue gas
 Structural foot deformities
– MRI is usually preferred over CT for investigation of
osteomyelitis.

15. Diabetic foot ulcer
– Evaluation of ulcer:
• Parameters that might have led to ulcer
• Presence of factors that can impair wound healing
• Description of ulcer
• Character of lesion
• Existence and character of odour should be noted

16. Wagner’s classification

17. Classification of diabetic foot

18. Treatment of diabetic ulcer
– Essential therapeutic areas of management:
 Management of comorbidities
 Evaluation of vascular status and treatment
 Lifestyle assessment and modification
 Ulcer evaluation and management
 Pressure relief

19. Tissue management
– Thorough evaluation
– Debridement:
 Cornerstone of management of ulcer
 Sharp debridement of all nonviable soft tissue and bone
 As deeply and proximally until healthy bleeding soft tissue encountered
 Main purpose is to convert a chronic ulcer into an acute, healing wound
 Repeated as often as needed
 Less frequent debridement can reduce rate of wound healing and increase the
risk of infection.

20. Other forms of debridement
– Enzymatic debridement : collagenases, plant derived papain
– Mechanical debridement: wet to dry dressings and high pressure
irrigation
– Biological therapy: larvae of lucilia sericata blowfly secrete
proteolytic enzymes that liquefies necrotic tissue.

21. Adjunctive modalities
– HBO (hyperbaric oxygen) therapy
– Growth factor therapy
– Bioengineered tissue
– NPWT (negative pressure wound therapy)

22. Pressure relief / off loading
– Reduction of pressure is essential to treatment
– Prevents further trauma and promotes wound healing
– Choice of modality should be determined by patient’s physical
characteristics and ability to comply with treatment.
 Total non-weight bearing: bedrest, crutches and wheel chair
 Total contact cast
 Modified surgical shoes
 Foam aperture pad

24. NICE guidelines (August 2015)
– Investigation:
• Document size, depth and position
• Use standardised system SINBAD, University of Texas system
– Treatment:
• Offer 1 or more: offloading, control of infection, wound debridement and
dressing.
• Consider NPWT after surgical debridement
• Do not offer following unless part of clinical trial-
 Autologous platelet rich plasma gel, growth factors
 Hyperbaric therapy

25. Clinical practical guideline (2016)
Society for Vascular Surgery in collaboration with the American
Podiatric Medical Association and the Society for Vascular Medicine
– Diabetic foot ulcer
• Frequent evaluation at 1-4 week interval
• Sharp debridement of all devitalised tissue and surrounding callus
• Initially sharp debridement with subsequent choice based on availability of
expertise and patient preference.
• Adjunctive therapies after minimum 4 week of standard wound therapy

26. Clinical practical guideline (2016)
Society for Vascular Surgery in collaboration with the American
Podiatric Medical Association and the Society for Vascular Medicine
– Offloading DFU:
• In patient with plantar DFU – offloading with TCC
• RCW in patient who require frequent dressing changes
• Non-plantar wound – use any modality that relieves pressure.

27. Diabetic foot infection
– Major reason for hospitalization among diabetics
– Important causal factor for amputation
– Classification:
 Non-limb threatening- superficial ulceration without ischemia, <2cm cellulitis
 No signs of systemic involvement
 Can be managed on outpatient basis
 Limb threatening- cellulitis beyond 2cm
 Fever, edema, lymphangitis, Hyperglycemia, ischemia
 Gangrene, abscesses, osteomyelitis and necrotising fasciitis may be present.

29. Treatment of non limb threatening
infections
– Initially treated in an outpatient setting.
– In addition to standard treatment for ulcer, oral antibiotic therapy
is sufficient as initial therapy.
– Antibiotic should be adjusted according to culture results and
patient’s response.
– Consider hospitalization with IV antibiotics if no improvement.

30. Treatment of limb-threatening
infections
– Patient requires emergent hospital admission for appropriate
intervention
– Thorough evaluation
– Radiographs are necessary to evaluate for evidence of
osteomyelitis and soft tissue gas
– Blood cultures are required if clinical finding indicate septicaemia.
– Multidisciplinary approach has been shown to significantly
improve outcome.

31. Treatment of limb-threatening
infections
– Early surgical treatment is necessary :
• May include simple debridement, incision and drainage or amputation to
eliminate areas of infection.
• Aerobic, anaerobic and fungal tissue culture should be obtained.
• Even sickest of patient should be considered for surgical intervention.
– Empiric antibiotics modified by culture directed antibiotics.

33. Treatment of limb-threatening
infections
– Wound care is initiated on day 1 or 2 post surgery.
– If wound fails to show signs of healing patient’s vascularity , nutritional status,
infection control and wound off-loading must be re-evaluated.
– Once soft tissue infection is under control consideration may be given to wound
closure or definitive amputation.
– Restoration and maintenance of function is the ultimate goal.

35. NICE guidelines (August 2015)
– Investigation:
• send soft tissue/bone sample from base of debrided wound for culture.
• Consider X-ray of the affected foot.
• If osteomyelitis is suspected and not confirmed by X-ray, consider MRI.
– Treatment:
• Start antibiotic treatment for suspected infection as soon as possible.
• Choose appropriate antibiotic regimen based on care setting, clinical situation and medical
history and cost.
• For mild infection initially offer oral antibiotic with activity against gram-positive organism.

36. NICE guidelines (August 2015)
– Treatment:
• For moderate and severe infection offer gram positive , gram negative and anaerobic
coverage.
• Offer prolonged antibiotic treatment to patient with diabetes and osteomyelitis.

37. Amputation
– Can be curative or emergent
– Indications:
 Removal of gangrenous tissue or infected tissue to control or arrest the spread of
infection.
 Removal of portion of foot that frequently ulcerates
 Creation of a functional unit

40. Prevention of diabetic foot
– Annual foot inspections.
– Foot examination should include testing for peripheral neuropathy.
– Education to patient and family about foot care.
– Adequate glycaemic control.