Diabetic Feet. Juanita Muller

Transcription

1 Diabetic Feet Juanita Muller

2 Mr RR 69 year old male CHARCOT ARTHROPATHY

3 Diabetic Feet Callus Acute injury and ulceration Infection Osteomylitis Chronic ulceration Ischaemic necrosis Charcot s arthropathy Amputation

4 Diabetic Feet Diabetics in Australia 275 patients diagnosed per day 1 million currently in Australia 70-80% of amputations have diabetes 85% of major and minor amputations are preceded by an ulcer Every 30sec patient has an amputation for diabetes

5 Etiology 1. NEUROPATHY 2. INFECTION 3. ISCHAEMIA

6 Etiology - Neuropathy Pathogenesis of Diabetic Neuropathy Alterations in vasa nervorum Ischaemic injury to the nerve Abnormalities in metabolism Increased activity in the polyol (sorbitol) pathway Decrease in neurotrophic factors Increased oxidative stress Advanced glycosylation end products (AGEs)

7 Etiology - Neuropathy AUTONOMIC Shunting tissue hypoxia Nociceptive reflex Loss of sweat and oil gland function

8 Etiology - Neuropathy MOTOR Intrinsic muscles of foot atrophy claw foot hallux valgus dislocated MTP joint SENSORY Pain and temperature High pressure penetrating injuries Low pressure repetitive stress Thermal injury

9 Etiology - Neuropathy JOINT ARTHROPATHY Sturctural foot abnormalities Charcot foot Painless, progressive and degenerative arthropathy of single or multiple joint Fracture, dislocation process Foot and ankle Aetiology Loss of proprioception joint injury

10 Etiology - Infection Skin breakdown portal of entry Systemic effects of diabetes Hyperglycemia immunocompromised state Hypoalbuminaemia Tissue ischaemia Microbiology Superficial infections Aerobic gram-positive cocci Staphylococcus aureus Coagulase negative staphylocicci β-haemolytic streptococcus Deep tissue infections = polymicrobial Gram positives: Staphylococcus/Streptococcus Gram negatives: E. coli, Proteus Anaerobes: Bacteroides, Clostridia Opportunisitic : Enterobacter, Pseudomonas, Yeast Osteomyelitis/Septic Arthritis

11 Etiology - Infection Pathogens Monomicrobial Polymicrobial Staphylococcus aureus Coagulase-negative staphylococci Streptococci Enterococci Klebsiella sp. Proteus sp. Other gram-negatives Pseudomonas aeruginosa Anaerobes Fungi Patients (%) with pathogens isolated Crayson ML et al Diabetic foot infections: anti-microbial therapy Infect Dis Clin North Am 1995;9:

12 Etiology - Ischaemia Macrovascular and Microvascular Atherosclerosis Occlusive disease of crural vessels Sparing of the foot Monckeberg s arteriosclerosis

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14 Diabetic Foot Risk Assessment University of Texas Diabetic Wound Classification System STAGE = wound type A Clean B Infected, not ischaemic C Ischaemic, not infected D Ischaemic and infected GRADE = involvement of deep structures 0 Healed ulcer 1 Superficial 2 Wound penetrating to tendon or capsule 3 Wound penetrating to bone and joint

15 History Diabetes history Length of time Insulin/oral medications/diet controlled BSL control/hba1c Associated neuropathy/retinopathy/nephropathy Peripheral neuropathy Glove and stocking distribution Asymptomatic Numbness, paraesthesia, burning sensation/pain Atherosclerotic risk factors Non-modifiable: Age, gender Modifiable: Hypertension, Dyslipidaemia, Smoking,

16 Examination Gait Vascular examination Inspection Palpation Auscultation Percussion

17 Examination The foot INSEPCTION Neuropathy Clawed foot appearance Dry, cracked skin Callus at points of increased pressure/weight bearing Atrophy of small muscles of foot Colour and temperature changes Hyperemic = acute Charcot fracture/infection/shunting Pale = concomitant ischaemia Charcot foot Rocker bottom deformity Crepitus Excessive range of motion, excessive subluxation

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20 Examination The foot INSEPCTION Ischaemia Cool, pale, atrophic skin changes Decreased capillary refill Decreased venous filling Berger s positive Infection Rubor, Calor, Dolor, Tumor

21 Examination Ulcer Deroof eschar Probe with sterile metallic probe Neuropathy Semms-Weinstein monofilament 10gm on off method Predictive risk for developing foot ulcer: Sensitivity 66-91% Specificity 34-86% Vibration sensation 128 Hz tuning fork

22 Investigation Assessment of Infection Plain X-ray Charcot disease Foreign bodies Osteomylitis Wound swab M/C/S Probe to bone Bone scan/mri/wcc labelled scan Bone biopsy

23 Investigation Assessment of Ischaemic component Toe pressures Ankle brachial pressure index Transcutaneous O2 measurements Duplex arterial ultrasound CT/MR Angiogram Angiogram

24 Investigation Assessment of Neuropathic deformity Xray MRI

25 Management Medical Management of diabetes Treat infection and sepsis Treat ischaemia Control for neuropathy/structural deformity Follow up and surveillance

26 Management Medical management of Diabetes HbA1c: % Blood pressure: <130/80mmHg LDL: <1.8mmol/L Associated co-morbidities Retinopathy Nephropathy Ischaemic Heart Disease

27 Managment Treat infection and/or sepsis Immediate surgical debridement/amputation Devitalized infected tissue Pus/Abscess Septic arthritis Necrotizing fasciitis Osteomyelitis 4-6 weeks antibiotics Surgical excision

28 Management Treat ischaemia limb salvage Arterial reconstruction Endovascular Intervention Hyperbaric oxygen therapy

29 Management Treat ischaemia Arterial reconstruction In-line flow vs Angiosomes

30 Management - Angiosomes Posterior Tibial Anterior Tibial Peroneal

31 Management Treat ischaemia Endovascular Intervention

32 Management

33 Management Treat ischaemia Hyperbaric oxygen therapy RCT 25/48 (52%) healed within 12 months with HBO 12/42 (27%) healed without HBO EJVS Guidelines HBO may be indicated for a selected group of diabetic ulcers, but it is not clear which patients are likely to benefit and what is the optimal duration [Level 1b, Grade A] Londahl et a. Hyperbaric oxygen therapy facilitates healing of chronic foot ulcers in patients with diabetes. Diabetes Care 2010; 33: Tan, T. et a. Inpatient management of diabetic foot problems: summary of NICE guidance. BMJ 2011;342:702-3

34 Management Control for Neuropathy Restriction of weight bearing Bed rest Debridement of callus Reduce peak plantar pressure Protective shoe wear Post op shoe Custom made orthortics Off-loading

35 Management Control for Neuropathy Management of Charcot foot Protect and prevent further collapse and deformity Protect the opposite foot Extended period of non-weight bearing (3-6months) Total contact boot immobilisation Management for painful neuropathy First line: Amytriptyline/Carbamazepine/Sodium valproate Second line: Gabapentin/Pregabalin

36 Management Control for Neuropathy Mechanical Offloading Surgical Offloading Arthroplasties Metatarsal head resections Achilles tendon lengthening Corrective surgery for structural deformities

37 Management Multi-disciplinary team Diabetic physician Diabetic educator Vascular surgeon Podiatrist Orthotist Orthopaedic surgeon Nurse

38 Management Surveillance Ulcer healing 50-60% healed at 20 weeks >75% at 1 year Limb salvage 80% at 1 year 70% at 3 years Mortality Diabetics with CLI 53% mortality at 6 months Operative mortality: 5% Quality of life