Peripheral vascular disease (PVD) affects 8 million adults in the United States with a disproportionately higher frequency among those who are homebound (Hamburg & Balady, 2011). This increase has been attributed to a higher prevalence of PVD risk factors among the homebound population such as advancing age, sedentary lifestyle, high cholesterol, hypertension, diabetes, tobacco use, heart disease, and stroke (Mayo Clinic, 2018). It is notable that less than half of individuals with PVD do not report claudication pain, a sensation of cramping pain in the lower extremities (Dhaliwal & Mukherjee, 2007). Therefore, it is important for home healthcare providers, including physical therapists (PTs), to observe and assess for signs and symptoms of PVD, as early identification can impact both the individual's short- and long-term health outcomes.
The initial PVD screening assessment should include a medical and social history with attention to modifiable risk factors including tobacco use, physical inactivity, and/or improper use of medication prescribed to control chronic conditions associated with PVD risk. Tobacco smoking can cause arteries to spasm and constrict, which in turn, decreases blood flow to the extremities. Tobacco use can also accelerate plaque formation in the arteries that will further compromise blood flow to the body (Argacha et al., 2008). Individuals who are contemplating quitting smoking can benefit from referral to, and support of, smoking cessation programs.
The Centers for Disease Control and Prevention (2020) recommends adults achieve 150 to 300 minutes of moderate, or 75 to 150 minutes of vigorous, activity each week. The positive impact of physical activity and exercise can be significant for individuals experiencing intermittent claudication (Agrawal & Eberhardt, 2015). Therapists are well positioned to dose exercise, create exercise prescriptions, and modify programs to meet the individual needs of each patient. Evidence suggests exercise that continues through the point of claudication pain, followed by a brief rest and then having the individual continue exercising, promotes collateral blood flow that increases blood supply to the distal extremity (Hamburg & Balady, 2011). Additionally, antihypertensives, lipid-lowering drugs, and medications used to control glucose levels can be beneficial to reduce atherosclerotic plaque formation, inflammation, endothelial dysfunction, hypercoagulability, and ultimately nonhealing ulcers (Huysman & Mathieu, 2009). Therefore, PTs have a role in monitoring medication compliance to assure chronic condition associated with elevated PVD risk is controlled.
An examination of the integumentary system is essential to screen lower extremities for skin changes, such as abnormal color or a shiny appearance, coldness or temperature change as well as weak pulses (Mayo Clinic, 2018). One reliable and efficient assessment of arterial sufficiency is known as the Buerger's test. During this test the vascular angle, also known as the Buerger's angle, examines to what degree the leg has to be raised from a dependent position before it becomes pale. The assessment is done while the patient is supine. An ischemic lower extremity demonstrates pallor after 30 to 60 seconds when elevated 15 to 30 degrees; whereas, normal circulation remains pink even when the lower extremity is raised by 90 degrees. Additionally, dependent rubor is characterized by a reddish or dusky-red skin hue when in a dependent position but not when elevated above the heart. The presence of either pallor or dependent rubor is indicative of vascular disease (Wright & Rajachandran, 2017). Another measure useful in screening for PVD is the ankle brachial index (ABI; DeTurk & Cahalin, 2018). It is relatively easy to perform, but efficiency requires practice. An online video demonstration titled Ankle Brachial Index Test (ABI): How to Perform is available at http://stanfordmedicine25.stanford.edu/the25/ankle.html (Standford Medicine 25, 2012). Additionally, Chaudru et al. (2016) provide detailed instruction relevant to the assessment protocol.
When calculating the ABI, each lower extremity pressure is individually divided by the highest upper extremity pressure (Table 1). The highest upper extremity systolic blood pressure, from either side, is used for this calculation irrelevant of the side of the lower extremity measurement. If the calculation results range from 1.00 to 1.40, the vascular system is considered normal. However, as the calculation values decrease, the risk of PVD increases. For example, a value in the range of 0.4 to 0.79 would indicate moderate-to-severe PVD. It is also notable that elevated values above 1.40 may indicate falsely elevated vessel pressures due to calcified vessels (Shu & Santulli, 2018). The interpretation chart depicted in Table 2 may be helpful to reference for further evaluation.
When screening suggests PVD may be present, the referring or primary care physician should be notified and a plan for further medical examination initiated. Sharing the observed findings with the patient is warranted, but should be approached judiciously to promote self-efficacy and not fear. Education and the development of a safe exercise prescription can be advantageous in PVD risk reduction with potential to optimize a patient's quality of life.
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