Arterial Studies And The Diabetic Foot Patient

Transcription

1 Arterial Studies And The Patient George L. Berdejo, BA, RVT, FSVU

2 Disclosures I have nothing to disclose!

3 Diabetes mellitus continues to grow in global prevalence and to consume an increasing amount of health care resources One of the key areas of morbidity associated with diabetes is the diabetic foot

4 Tibial disease with the clinical presentation of CLI is associated with a high rate of limb loss due to amputation Common and especially true in the diabetic population Physical examination is critical but often is limited secondary to edema, infection, tissue loss The pulse examination is subjective and significantly compromised

5 Serious complication Approximately 20 25% of diabetic patients will present with lower extremity ulceration at some time in their lives Amp risk for diabetic patients is ~40x greater than that of the general population Post-amputation mortality is extremely high, with a three-year survival rate of 65% and a five-year survival rate of 41%

6 Diabetic foot ulcer Major complication of DM, and probably the major component of the diabetic foot. Patients will require objective testing in order to assess flow status and potential for healing

7 Diabetic Care Optimal care requires a multidisciplinary management approach Prior history of DFU Prior abnormal vascular examination Prior intervention for peripheral vascular disease or Known atherosclerotic cardiovascular disease (eg, coronary, cerebral, or renal) Have vascular examination of the lower extremities and feet including the evaluation of extremity perfusion

8 Ankle Brachial Index and Toe Pressures

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10 Pulse Volume Recording (PVR) Measures pressure changes in the bladder of the cuff wrapped around the limb The cuff pressure changes reflect changes in cuff volume corresponding to changes within the limb volume Normal PVR has a rapid upstroke with a dicrotic notch Advantage is that it is not affected arterial calcification Disease progression Very reliable assessment of global arterial perfusion

11 Continuous-wave Doppler Utilizes continuous transmission and reception of ultrasound waves Allows for assessment of individual arteries only Blind technique Like all other Doppler analysis is angle dependent Operator dependent Does not provide assessment of global arterial perfusion

12 Duplex Spectral Doppler Doppler scanning of dorsalis pedis Derived artery, Waveforms posterior tibial artery, popliteal artery Utilizes PW Doppler w imaging If Doppler ultrasonography was triphasic, it was graded as normal, biphasic as mild, Use the monophasic B-mode as image moderate to and no sound was heard then severe grade of vasculopathy direct the sample volume Not a blind technique Diabetic, male smokers biggest risk factor was they worked Less barefoot operator outdoors dependent thus more prone to trauma and predisposed to ischemic foot ulceration esp in the Still assessment of individual presence of PAD arteries only Does not provide assessment of global arterial perfusion

13 The SPP and TcPO 2 - Examine the microcirculation or skin capillaries within the skin layer Transcutaneous oxygen (TCOM or TcPO 2 ) Measurements Oxygen level of the tissue below the skin Indirect measure of blood flow Useful for predicting wound healing and whether a patient would benefit HBOT Noninvasive but takes up to 45 minutes to complete Nml oxygen tension is > 40 mmhg in a patient with diabetes, then the wound should heal, <20mmHg unlikely to heal Skin Perfusion Pressure Measurements Laser Doppler probe placed near the wound under a blood pressure cuff The test determines how much blood is flowing around the test site Converts optical information into the skin perfusion pressure Takes approximately 5-10 minutes but may need more than one site evaluated Thought to be more sensitive than TCOM for wound healing Edema, acute local infection, and vasoconstriction during sepsis, which will all decrease the values

14 Other Perfusion Testing Near infrared spectrometry Laser Doppler flux Emerging although not widely used tools for the assessment of deep tissue and skin perfusion

15 Conclusion Many options available for the evaluation of perfusion and potential for wound heling Some evaluate macro others the micro circulation Time and technique variable Pick the modality that best answers the clinical question and suits the need of the patient population and available resources

16 SPP and TcP02 / TCOM both assess microcirculation; however, SPP is proving to be faster, more efficient, and more cost-effective test.