This Just In Susan Simmons Holcomb, PhD, ARNP, BC This Just In Editor

PAOD Testing in Diabetic Patients

Diabetes mellitus is a major risk factor for lower extremity amputa- identify the disease and initiate factor for the development of car- tion and yet, to date, there are no treatment quickly. diovascular disease, including pe- guidelines for the prevention, identi- ripheral arterial occlusive disease fication, and treatment of PAOD in ■ Identifying PAOD (PAOD) or peripheral arterial dis- diabetic patients. Twenty percent of In the past, identification of PAOD ease. Approximately 20% of the 12 diabetic patients older than 40 years was done by clinically analyzing re- million Americans identified in the of age have PAOD and 29% of dia- ported symptoms of claudication or Framingham Heart Study as having betic patients over 50 years of age absence of palpable peripheral symptomatic PAOD were diabetics.1 have PAOD. Twenty-seven percent of pulses. However, these methods are However, this estimate may be low. diabetic patients with PAOD will insensitive and may not identify pa- tients early enough. A more sensitive test is the ankle-brachial index Nurse practitioners must be able to identify PAOD and (ABI). The ABI is obtained by mea- initiate treatment quickly. suring systolic blood pressures in the ankles and arms via a Doppler and then calculating a ratio between the Experts believe over one-half of dia- have disease progression within 5 two. When compared to angiograph- betic patients with PAOD are years; 4% of those patients will re- ically determined arterial disease, asymptomatic, approximately one- quire amputation, and 20% will ex- measuring ABI is 95% sensitive and third have claudication, and the re- perience nonfatal cardiovascular almost 100% specific.1 However, maining patients have extremely events such as myocardial infarction sensitivity decreases in the elderly severe symptomatic disease. Claudi- or stroke.1 In patients with chronic and in some diabetic patients who cation is defined as intermittent limb ischemia, 30% will have ampu- have artificially elevated pressures. pain, cramping, or aching in the tations and 20% will die within 6 Calcified, poorly compressible ves- lower extremities that occurs when months.1 sels, and vessel stenosis in these pa- walking, and is relieved by rest. Se- In 2003, the American Diabetes tients account for potential vere disease may present as resting Association developed a consensus inaccuracies. claudication, gangrene, and need for statement addressing the issue of amputation. Severe disease is also PAOD in the diabetic patient. The ■ Evaluation termed “critical limb ischemia.”The full consensus statement can be Evaluation of the potential PAOD greatest risk factors for the develop- found in the December 2003, issue patient includes a detailed history ment of PAOD include smoking and of Diabetes Care or online at http:// and physical examination. The his- diabetes mellitus. African Americans www.care.diabetesjournals.org/egi/ tory should include ambulation. The and Hispanic diabetics have the content/full/26/12/3333.1 Since dia- physical exam should concentrate on greatest risk. Other risk factors in- betes is one of two major risk fac- potential PAOD findings such as de- clude aging, hypertension, hyperlipi- tors for the development of PAOD pendent rubor, pallor with elevation, demia, and duration of diabetes and because over one-half of dia- absence of hair growth on the lower greater than 10 years. betic patients may have the disease extremities, dystrophic toenails, cool but be asymptomatic, it is impera- and dry skin, and weak or absent ■ PAOD in Diabetics tive that nurse practitioners have a pedal pulses. Examination of pulses Peripheral arterial occlusive disease strong suspicion of PAOD in dia- of the lower extremity should in- in diabetic patients is a major risk betic patients and the ability to clude the femorals and popliteals, as

6 The Nurse Practitioner • Vol. 29, No. 11 www.tnpj.com Literature Review

evaluation, treadmill testing, duplex Ankle-Brachial Index (ABI) sonography, magnetic resonance an- (ankle systolic/brachial giography, x-ray angiography, and systolic = ABI) transcutaneous partial pressure of oxygen. Vascular lab evaluation in- ABI value Significance cludes segmental pressures and MUSCULOSKELETAL CARE 0.91 to 1.30 Normal pulse volume recordings at the toe, ankle, calf, low thigh, and high ■ Wrist Injury—Scaphoid 0.70 to 0.90 Mild obstruction thigh. The values help to determine Fracture 0.40 to 0.69 Moderate obstruction vessel lesion location. Treadmill test- Phillips TG, Reibach AM, Slomiany WP: ing can illicit claudication symp- Diagnosis and management of scaphoid < 0.40 Severe obstruction toms and can also determine if the fractures. Am Fam Physician treatment for PAOD is working. 2004;70(5):879-84. 1.30* Poorly compressible Sonography and magnetic reso- Young men who fall with their *May be poorly compressible at an- nance imaging can identify specific hands outstretched are more likely kle due to calcification. This value is lesions and/or blood vessel wall ab- to receive a scaphoid fracture than considered unreliable and should normalities and invasive angiogra- similar injuries in young children not be considered normal. phy can be useful prior to surgical or the elderly that result in a frac- Adapted from: American Diabetes Association procedures such as angioplasty. ture of the distal radius. It is impor- and the American College of Cardiology. Peripheral arterial disease in diabetes. Testing diabetic individuals for tant to identify scaphoid fractures Diabetes & Cardiovascular Disease Review PAOD should be considered, along and provide correct therapy be- 2004, Issue 6, page 2. with the normal vital signs of blood cause nonunion related to a poor pressure, heart rate, respiratory rate, blood supply can complicate heal- well as the pedal pulses. After taking and temperature. Smoking is also a ing. Because early imaging is often the history and completing the major risk factor, so a smoking his- negative, the practitioner needs a physical examination, calculate the tory should be obtained at each high index of clinical suspicion to ABI. visit. In diabetics, feet are evaluated catch this diagnosis. The pain may To correctly perform the ABI, at every visit. Peripheral arterial oc- be dull and deep in the radial wrist, place the patient recumbent for 5 clusive disease screening should be worsened by gripping or squeezing. minutes. Next, measure the systolic done in all diabetics by the age of 50 Anatomic snuffbox tenderness is a blood pressure in both arms and use years, and in younger diabetics with very sensitive test (90%), but it is the higher value for the brachial risk factors such as smoking, hyper- nonspecific (40%). In a second ma- portion of the index. Then, measure tension, hyperlipidemia, or diabetes neuver, tenderness over the the systolic blood pressure in the an- for longer than 10 years. Screening is scaphoid tubercle is elicited with kles using the dorsalis pedis and done using the ABI. In patients with the patient’s wrist extended. This posterior tibial arteries. Place the a normal ABI, a rescreen should be maneuver is also sensitive (87%), blood pressure cuff just above the done in 5 years. In patients with ab- but more specific (57%). Absence ankle and use a Doppler for ascer- normal ABI measurements, treat- of tenderness with these two ma- taining the systolic blood pressure. ment should be initiated and neuvers makes a scaphoid fracture As with the brachial portion, use the rescreening done on a reduced highly unlikely. The authors suggest higher ankle systolic pressure value. schedule. It may be helpful to com- that a patient with clinically sus- Divide the brachial reading into the plete an ABI at least on a yearly ba- pected scaphoid fracture but nega- ankle reading to get the ABI (see sis, along with checking for tive initial radiographs should have Table: “Ankle-Brachial Index”). microalbuminuria. a short arm thumb spica cast ap- plied and be reevaluated in 2 weeks ■ Other Tests REFERENCES because the fracture can worsen if 1. American Diabetes Association. Peripheral arter- In patients who have poorly com- ial disease in people with diabetes, consensus the injury is not cast. Either mag- pressible arteries or in patients who statement. Diabetes Care 2003;26(12): 3333-41. netic resonance imaging or a bone warrant follow-up, additional test- 2. American Diabetes Association and the Ameri- scan are equally appropriate to con- can College of Cardiology. Peripheral arterial dis- ing should be ordered. Potential ad- ease in diabetes. Diabetes and Cardiovascular firm a fracture when the initial ra- ditional tests include vascular Disease Review 2004: 6, 1-9. diographs are negative. www.tnpj.com The Nurse Practitioner • November 2004 7