DIABETIC FOOT SYNDROME – An Indian Perspective – Apropriate technology

1. DIABETIC FOOT SYNDROME – An Indian Perspective – Apropriate technology DR. ASHOK KUMAR DAS DEAN, DIRECTOR-PROFESSOR & HEAD, DEPARTMENT OF MEDICINE, JIPMER, PONDICHERRY

2. ISSUES COST CLASSIFICATION HIGH RISK FOOT CLINICAL EVALUATION HISTORY PHY EXAM LAB TECHNOLOGY MANAGEMENT 6 CONTROLS INDIAN PROBLEMS & SOLUTIONS DIABETIC FOOT CLINIC CONCLUSIONS AGENDA

3. INTRODUCTION • FOOT PROBLEMS - AN IMPORTANT CAUSE OF MORBIDITY IN DIABETIC PEOPLE • 2025 THERE EXPECTED TO BE 75 MILLION DIABETICS • 150 MILION FEET

4. TYPES OF DIABETIC FOOT • NEUROPATHIC FOOT (COMMONEST) • ISCHEMIC FOOT

6. DIAGNOSIS OF A ‘HIGH RISK’ FOOT • PERIPHERAL NEUROPATHY • SOMATIC • AUTONOMIC • PERIPHERAL VASCULAR DISEASE • PREVIOUS FOOT ULCERS • FOOT DEFORMITY • CLAW TOES • CHARCOT ARTHROPATHY

7. PRESENCE OF CALLUS • BLIND OR PARTIALLY SIGHTED • NEPHROPATHY • ELDERLY • POOR UNDERSTANDING OF DIABETES • INABILITY TO FEEL SEMMES-WEINSTEIN NYLON MONOFILAMENT

8. TECHNOLOGY & DIABETIC FOOT • UTILISED MAINLY • SCREENING • DIAGNOSIS OF HIGH RISK FOOT • DIAGNOSIS OF EXTENT OF INVOLVEMENT • PROGNOSTICATION • TREATMENT OF DIABETIC FOOT

9. TECHNOLOGY & DIABETIC FOOT… • HI TECH EDUCATION • AWARENESS & EDUCATION • PERSONS WITH DIABETES & DIABETIC FOOT CARE PROVIDERS • viz…diabetic foot pressures & its improvement with insoles etc.

10. TECHNOLOGY & DIABETIC FOOT… • Quantification & research • Natural history of Diabetes & its complications • Drug trials • Evidence based Diabetology Practice • viz …diabetic Neuropathy

11. AREAS & APPLICATION OF TECHNOLOGY IN DIABETES PRACTICE 2004 • Diabetic foot pressure studies: • out of shoe • in shoe • emed • pedomed • f-scan

12. Introduction of opticalpedobiographs & development of computing technology • microprocessor like recording devices • provide—possibility of identifying patients at risk of plantar ulceration • give basis for • foot wear prescription & adjustment • surgical intervention • Hi tech education

13. COST • FOOT COSTS A MAJOR COMPONENT OF DIABETES RELATED HEALTH-CARE EXPENDITURE • IN US, COSTS OVER $500 MILLION PER YEAR • IN UK, OVER £13 MILLION PER YEAR

14. CLINICAL ALGORITHM

15. CLINICAL EVALUATION • ALWAYS PRECEDES ANY LABORATORY INVESTIGATION • GOOD HISTORY AND THOROUGH PHYSICAL EXAMINATION WILL REDUCE NEED FOR MANY UNNECESSARY AND COSTLY INVESTIGATIONS

16. HISTORY • VASCULAR / NEUROGENIC CLAUDICATION • PREVIOUS ULCERATION / AMPUTATION • PATIENT UNDERSTANDING OF DM & COMPLICATIONS

17. PHYSICAL EXAMINATION • SHAPE & DEFORMITIES • TOE DEFORMITIES, NAIL DEFORMITIES • HALLUX VALGUS, HALLUX RIGIDUS • PROMINENT METATARSAL HEADS • HAMMER TOE • CHARCOT DEFORMITY • CALLUS

18. SENSORY FUNCTION • VIBRATION (128 HZ TUNING FORK) • THERMAL PROPRIOCEPTION • JOINT POSITION SENSE

19. MOTOR FUNCTION • WASTING • WEAKNESS • LOSS OF ANKLE REFLEXES

20. AUTONOMIC FUNCTION • REDUCED SWEATING • CALLUS • WARM FOOT • DISTENDED DORSAL FOOT VEINS

21. VASCULAR STATUS • FOOT PULSES • PALLOR • COLD FEET • EDEMA

22. NEUROPATHY ISCHEMIA DEFORMITY CALLUS OEDEMA SKIN BREAKDOWN INFECTION NECROSIS CLINICAL ASSESSMENT - EIGHT COMPONENTS

23. STAGING THE DIABETIC FOOT

24. LABORATORY EVALUATION OF THE VASCULAR SYSTEM • INDIRECT METHODS • DIRECT METHODS

26. DOPPLER ULTRASOUND PHOTOPLETHYSMO GRAPHY PULSE VOLUME RECORDING LASER DOPPLER FLUX TRANSCUTANEOUS OXYGEN TENSION ISOTOPE CLEARANCE INDIRECT METHODS

27. DIRECT METHODS • DUPLEX SCANNING • MAGNETIC RESONANCE IMAGING • ARTERIOGRAPHY

28. DOPPLER ULTRASOUND AND DOPPLER PRESSURES • METHODS INCLUDE • DOPPLER SIGNAL WAVE FORM • ANKLE DOPPLER PRESSURE • ANKLE - BRACHIAL INDEX • DOPPLER SEGMENTAL PRESSURES

29. DOPPLER USG - MOST WIDELY USED DEVICE • RANGES FROM A POCKET SIZE DEVICE TO LARGE, STATIONARY COMPLICATED DEVICE • AUDIBLE SIGNALS EVALUATED BY HEAD-PHONES OR LOUD SPEAKER

30. DOPPLER SIGNAL WAVE FORM • NORMAL ARTERIAL DOPPLER WAVE FORM IS TRIPHASIC • SYSTOLIC UPWARD DEFLECTION • DIASTOLIC DOWNWARD DEFLECTION • SMALLER UPWARD AND DOWNWARD DEFLECTION (DIASTOLIC FORWARD FLOW)

31. ANKLE - BRACHIAL INDEX • DOPPLER PROBE USED TO MEASURE SYSTOLIC PRESSURE AT BRACHIAL ARTERY AND DORSALIS PEDIS/POSTERIOR TIBIAL ARTERY • NORMALLY, ANKLE PRESSURE / BRACHIAL PRESSURE = 1 OR SLIGHTLY ABOVE • ABI CORRELATES WITH SEVERITY OF ISCHEMIA

32. ABI • ABI OF 0.8 - 0.5 --- • INTERMITTENT CLAUDICATION • ABI OF < 0.5 --- • REST PAIN • A CHANGE OF 0.15 IS CONSIDERED SIGNIFICANT

34. SEGMENTAL PRESSURES • USED TO LOCALIZE VASCULAR OBSTRUCTION • MEASUREMENTS WITH PNEUMATIC CUFFS ARE MADE FROM • HIGH THIGH • LOW THIGH • BELOW KNEE • ANKLE LEVEL

35. PRESENCE OF GRADIENT BETWEEN MEASUREMENTS INDICATES A SIGNIFICANT STENOSIS OR A COMPLETE OCCLUSION IN THE ARTERIAL SEGMENT BETWEEN THE TWO CUFFS

36. EXERCISE FOR DIAGNOSIS • CAN UNMASK OBSTRUCTION • CAUSES A DROP IN DOPPLER PRESSURES DISTAL TO OBSTRUCTION, AFTER EXERCISE • DIFFERENTIATES VASCULAR FROM NON-VASCULAR ETIOLOGY FOR CLAUDICATION

37. ANKLE DOPPLER PRESSURE • SEVERITY OF LOWER EXTREMITY ISCHEMIA • SYSTOLIC PRESSURE AT ANKLE • APPROPRIATE SIZED CUFF IS USED • POSTERIAL TIBIAL / DORSALIS PEDIS • THE HIGHER READING IS TAKEN

38. ANKLE DOPPLER PRESSURE • ABSOLUTE ANKLE PRESSURE IS THE BEST PREDICTOR OF LIMB VIABILITY • > 60 MM HG = 86% OF VIABLE LOWER EXTREMITIES • < 60 MM HG = 77% OF NON-VIABLE EXTREMITIES

39. PHOTOPLETHYSMOGRAPHY • USES A DIODE THAT EMITS INFRA-RED LIGHT INTO THE TISSUE, WHICH IS REFLECTED BACK FROM THE BLOOD IN THE CUTANEOUS MICROCIRCULATION • TWO MEASUREMENTS • TOE BLOOD PRESSURE • SKIN PERFUSION PRESSURE

40. TOE BLOOD PRESSURE • FALSE HIGH DOPPLER PRESSURES IN CASE OF CALCIFIED VESSELS • ESPECIALLY USEFUL WHEN THE PATHOLOGY IN VESSELS IS BELOW THE ANKLE • BUERGER’S DISEASE • RAYNAUD’S PHENOMENON • LOWER LIMIT OF NORMAL FOR TOE PRESSURE IS 50 MM HG

41. SKIN PERFUSION PRESSURE • A GOOD PREDICTOR OF HEALING OF ULCER AND AMPUTATION SITES • SKIN PERFUSION PRESSURE OF 21 MM HG OR ABOVE FOUND TO CORRELATE WITH HEALING AND DECREASED COMPLICATION RATE OF THE AMPUTATION SITE

42. PULSE VOLUME RECORDER • SEGMENTAL PLETHYSMOGRAPH IS USED • CHANGES IN EXTREMITY OR DIGIT VOLUME THAT TAKES PLACE IN RESPONSE TO ARTERIAL PULSATION IS MEASURED

43. NORMAL WAVE PEAKED BRISK ANACROTIC AND DICROTIC DEFLECTIONS DICROTIC NOTCH ABNORMAL WAVE FLATTENED WAVE ABSENCE OF DICROTIC NOTCH REDUCED ANACROTIC / DICROTIC COMPONENTS PULSE CONTOUR

44. PULSE AMPLITUDE • ARTERIAL OCCLUSIVE DISEASE IS MARKED BY DECREASE IN AMPLITUDE OF THE PULSE WAVE FORM • AMPLITUDE < 15 MM - FOOT PAIN LIKELY ISCHEMIC • AMPLITUDE < 5 MM - FOOT ULCER UNLIKELY TO HEAL

46. TRANSCUTANEOUS OXYGEN TENSION (TCPO2) • MODIFIED CLARK ELECTRODE THAT MEASURES PARTIAL PRESURE OF O2 THAT DIFFUSES THROUGH SKIN • GOOD ULCER HEALING IF TCPO2 > 35 - 40 MM HG • POOR ULCER HEALING IF TCPO2 < 20 - 26 MM HG

47. LASER DOPPLER FLUX • ALSO CALLED VELOCIMETRY • PROVIDES A DIRECT & CONTINUOUS MEASUREMENT OF SKIN CAPILLARY BLOOD FLOW VELOCITY • SENSITIVITY LESS THAN TCPO2

48. ISOTOPE CLEARANCE • 133XE GAS ISOTOPE TO MEASURE SKIN BLOOD FLOW • FLOW RATES ABOVE 2.6 ML / 100 GM TISSUE CORRELATED WITH GOOD HEALING

49. DUPLEX SCANNING • COMBINATION OF REAL TIME B MODE SONOGRAPHY AND A PULSE DOPPLER • ALLOWS 2-D VISUALIZATION OF BLOOD VESSEL WITH SURROUNDING TISSUES • DETECTS CALCIFIED PLAQUE, ULCER, THROMBI, ANEURYSMS

50. COLOUR FLOW DOPPLER • DISPLAY OF FLOW IN VESSELS IN DIFFERENT COLOURS DEPENDING ON DIRECTION OF FLOW • ACCURACY OF 77% - 97% • TIME-CONSUMING AND NEEDS SKILL