EVALUATION OF THE VASCULAR STATUS OF DIABETIC WOUNDS Travis Littman, MD NorthWest Surgical Specialists

EVALUATION OF THE VASCULAR STATUS OF DIABETIC WOUNDS Travis Littman, MD NorthWest Surgical Specialists

Nothing To Disclosure

DISCLOSURES I have no outside conflicts of interest, financial incentives, or other disclosures

OBJECTIVES Identify when further Vascular intervention is indicated What is the initial foot evaluation What can Physical Exam tell us What tests should be ordered as part of the initial work up Describe and Define the various modalities available for further evaluation Define a potential treatment algorithm when vascular compromise is suspected.

65M PRESENTS TO CLINIC

EPIDEMIOLOGY Diabetes in the most common cause of Foot ulcers Infections Ischemia Amputations ~25% of diabetic pts will get an ulcer 50% of diabetic foot ulcers get infected 20% of these require amputation 85% of all diabetic lower extremity amputation are preceded by ulceration

AMPUTATION 90,000 amputations are done on diabetics each year 70-80% of non-traumatic amputations are done on diabetics Up to 17% will require a 2 nd amputation during the first year After one limb is injured, 50% will develop a serious wound on the contralateral limb Up to 70% will lose their other limb within 5 years

AMPUTATION 5 year mortality rate for major lower extremity amputations

PROGRESSION OF DISEASE Diabetes Neuropathy PAD Ulceration Infection Amputation

CAUSES OF ULCERS Neuropathy Autonomic, Motor, Sensory Abnormal Mechanics Bony Deformity PAD Trauma Ulceration Poorly Fitting Shoes

CAUSES OF ULCERS Ischemia Diabetic Neuropathy

CLINICAL PRESENTATION Ulcers can involve any part of the toes, foot, or ankle Complicated by Neuropathy May, or may not, present with claudication Be worried if: Pain Drainage Malodor Signs of Infection

DIABETIC FOOT RISK ASSESSMENT History Foot wounds? Amputations? Prior Surgery (Bypass/Stent) Exam Check for pulses Evaluate the Skin Check for neuropathy Look for Ulcers Foot Structure Joint Mobility

EARLY WORKUP Checking pulses Femoral Popliteal Posterior Tibial Dorsalis Pedis

DIABETES Creager M A et al. Circulation 2003;108:1527-1532 Copyright American Heart Association

EARLY WORKUP

EARLY WORKUP Checking pulses Evaluate the Skin Dry Hairless Dependent Rubor

EARLY WORKUP Checking pulses Evaluate the Skin Evaluate for Neuropathy

EARLY WORKUP Checking pulses Evaluate the Skin Evaluate for Neuropathy Look for Ulcers Check between toes In Creases Socks and shoes are off

EARLY WORKUP Checking pulses Evaluate the Skin Check for Neuropathy Look for Ulcers Classify the Ulcer Depth, size Infection Probe to Bone PPV (~50%) NPV (97%) Lavery LA et al. Diabetes Care 2007; 30:270-274.

ULCER CLASSIFICATION IWGDF International Work Group for Diabetic Foot 0 1 2 3 No Issues Neuropathy A: Neuropathy & deformity B: PAD A: Hx of Ulcer B: Amputation Meggitt-Wagner Grade Description 0 Pre-ulcerative lesion 1 Superficial Ulcer 2 Deep Ulcer 3 Deep Ulcer with Infection 4 Forefoot Gangrene 5 Whole foot Gangrene

UNIVERSITY OF TEXAS WOUND CLASSIFICATION SYSTEM Class A B C D Pre-ulcerative Healed +Infection - PAD -Infection +PAD +Infection +PAD Wound Depth 0 1 2 3 Superficial Skin/Sub-Q +Infection - PAD -Infection +PAD +Infection +PAD Deep Tendon/Capsule +Infection - PAD -Infection +PAD +Infection +PAD Deep Bone/Joint +Infection - PAD -Infection +PAD +Infection +PAD Armstrong DG et al. Diabetes Care 1998; 21:855-859.

MULTI-SPECIALTY CARE

PREDICTING ULCER HEALING ABI Toe Pressures TcPO2 Duplex Arterial Imaging

NON-INVASIVE TESTING ABI The reference standard for PAD Sensitivity 97% Specificity 100% In Diabetics -due to calcification- ABI falsely elevated (falsely normal) ABI >1.3 requires additional testing

NON-INVASIVE TESTING ABI The reference standard for PAD Sensitivity 97% Specificity 100% In Diabetics -due to calcification- ABI falsely elevated (falsely normal) ABI >1.3 requires additional testing

NON-INVASIVE TESTING ABI The reference standard for PAD Sensitivity 97% Specificity 100% In Diabetics -due to calcification- ABI falsely elevated (falsely normal) ABI >1.3 requires additional testing Yao JST. Br J Surg. 1970;57:761

NON-INVASIVE TESTING TOE PRESSURES Usually accurate in Diabetics Digital arteries are seldom calcified

NON-INVASIVE TESTING TOE PRESSURES Usually accurate in Diabetics Digital arteries are seldom calcified Ramsey DE. J Cardiovasc Surg. 1983;24:43.

NON-INVASIVE TESTING SEGMENTAL PRESSURES Give hints as to the level of disease A decrease of >20mmHg at any level indicates dignificant disease Normal Iliac SFA Iliac & SFA Below Knee Arm 120 120 120 120 120 Upper Thigh Above Knee Below Knee 160 110 160 110 160 150 100 100 70 150 140 90 90 60 140 Ankle 130 80 80 50 90

NON-INVASIVE TESTING PITFALLS Using L or R UE pressure: want to take the higher of the two Failure to have pt supine for 5 minutes or longer Proper cuff size Small (higher pressure), Large (lower pressure)

NON-INVASIVE TESTING DOPPLER/DUPLEX Normal flow is brisk triphasic Arterial stenosis flattens the waveform Doppler looks at flow and can determine Shift f = 2Vf 0CCCC C

NON-INVASIVE TESTING DOPPLER/DUPLEX

NON-INVASIVE TESTING DOPPLER/DUPLEX Stenosis (%) Peak Velocity (cm/s) Velocity Ratio Distal Artery waveform <20% <150 <1.5 Triphasic, normal PSV 20-49% 150-200 1.5-2 Triphasic, normal PSV 50-75% 200-300 2-4 Monophasic, reduced PSV >75% >300 4 Damped, monophasic

NON-INVASIVE TESTING DOPPLER/DUPLEX Highly user dependent Velocity across multi-level stenosis is less reliable Critical Stenosis Loss of triphasic waveform Broadening with PSV >200

NON-INVASIVE TESTING TCPO2 Skin probes measure ppo2 Essentially looks at the extra oxygen available TcPO2 of 0 means that all diffusing oxygen has been consumed

NON-INVASIVE TESTING TCPO2 Normal >55 Marginal healing 20-40 Poor healing <20

NON-INVASIVE TESTING TCPO2 Factors affecting TcPO2 Skin temperature Sympathetic tone Body Temperature Cellulitis Hyperkeratosis Obesity Edema Metabolic Activity Oxygen diffusion through tissue Oxyhemaglobin curve Increased venous Pressure Vertical Position relative to the heart Age

SO WHAT S THE KEY!

DON T WAIT TOO LONG!

WHEN AN ULCER IS PRESENT Careful Foot Exam?Pulses? No ABI Testing Arterial Duplex <0.5 Yes >0.5 Local Wound Treatment Charcot Evaluation Medical Adjuncts Vascular Evaluation Arterial Imaging Endovascular Options Surgical Options Amputation Debridement

QUESTIONS?