Ankle-Brachial Index and Wound Classification Teaching to Providers as Part of a Comprehensive Limb Preservation Outreach Program

Abstract

Dissemination and use of evidence-based specialty guidelines is frequently low in primary care settings. Early use of ankle-brachial index (ABI) testing and a validated wound classification system including ischemia allows prompt referral of patients for appropriate specialty care. We implemented a program to teach providers ABI testing and use of the Wound, Ischemia, and foot Infection (WIfI) classification tool. Here we report program outcomes and provider perceptions. Physicians and nonphysicians from local wound care centers, nursing and physician education programs, primary care offices, and federally qualified health centers were recruited to participate in two educational modules on ABI testing and use of the WIfI tool. Pretest and post-test responses and intention to use the content in the future were assessed using descriptive statistics. There were 101 participants who completed the pretest and post-test of the ABI module. 84 indicated their occupation (59 physicians, 25 nonphysicians). Seventy participants completed the WIfI module (50 physicians, 20 nonphysicians). Physicians had lower pretest knowledge scores of ABI and WIfI principles than nonphysicians (mean score, 7.9 and 8.2, respectively) (Table I). Both groups significantly increased their scores on the post-test (physicians = 13.4; nonphysicians = 13.8; P < .001). Nonphysicians in practice longer than 10 years who worked at wound care centers had the lowest baseline knowledge scores, whereas physicians in practice more than 10 years had the highest. In the ABI testing module, the largest knowledge gap for providers included how to accurately calculate the ABI based on measurements, followed by how to hold the Doppler, and management of patients with incompressible vessels (Table II). For the WIfI module, providers were unfamiliar with accurately scoring participants based on the wound stage. The greatest barriers to use of ABI testing were availability of trained personnel, followed by limited time to complete testing. Barriers to use of the WIfI tool for physicians included lack of time and national guideline support. For nonphysicians, the most notable barrier was a lack of adequately trained personnel. Both physician and nonphysician understanding of the ABI and WIfI tools is limited in wound care centers, primary care offices, and federally qualified health centers. Further barriers include lack of dedicated training in use of tools, limited potential for point of care ABI testing reimbursement, and insufficient dissemination of guidelines for use of the WIfI tool. Such barriers discourage widespread adoption in primary care settings, leading to delayed diagnosis of arterial insufficiency in patients with lower extremity wounds.Table IBaseline ankle-brachial index (ABI) knowledge based on years in practice and provider typeProvider typeYears in practice% ParticipantsPretest mean (standard deviation)Nonphysician1-3597.80 (3.26)4-10247.25 (2.06)>10176.67 (3.06)Physician1-3708.00 (2.23)4-1087.00 (5.00)>10229.44 (1.59) Open table in a new tab Table IIPretest questions with >60% incorrect answersQuestion% IncorrectA 62-year-old man is being seen to evaluate leg pain associated with walking. You obtain the following brachial and tibial vessel pressures (mm Hg). Right brachial = 128, Left brachial = 134, Right dorsalis pedal = 120, Right posterior tibial = 122, Left dorsalis pedal = 110, Left posterior tibial = 119 What is the ankle-brachial index for the right lower extremity?79%Which of these is the suggested Doppler angle for obtaining arterial Doppler signals?64%While performing the ankle brachial index test, a patient's highest arm pressure is 134 but the tibial pressure is raised to over 220 and the Doppler signal can still be heard. Given the high ankle pressure, which is the most appropriate next step?61% Open table in a new tab