Usefulness of ankle brachial pressure index measured using photoplethysmography and automated blood pressure measurement device

Lee, Chang Won; Park, Keun Yong; Son, Seok Man; Kim, In Ju; Kim, Yong Ki

Abstract

BACKGROUND: Resting ankle brachial pressure index is a non-invasive method to assess the patency of lower extremity arterial system and it can be measured using traditional Doppler method or photoplethysmography. Automated blood pressure measurement is a easy and quick method for measurement of ankle brachial pressure index, but usefulness of this method have not been investigated. So we evaluated the accuracy of Automated blood pressure measurement device as flow detector in determining the ankle brachial pressure index in comparison to photoplethysmography.
METHODS
A total 136 subjects containing 117 diabetic patients and 19 volunteers were included in the study. With each subject in the supine position, dorsalis pedis arterial pulses were palpated by examiner. And the brachial and ankle systolic blood pressure were recorded using photoplethysmography (Rheoscreen, Medis, Germany) and automated blood pressure measurement device (MD-800, Meditec, Korea). Ankle brachial pressure index for each leg was separately calculated by dividing the ankle systolic pressure by the higher brachial systolic pressure. Statistical analyses were performed by SPSS for Windows (version 10.0 SPSS Inc.)
RESULTS
Brachial and ankle systolic pressure measured using automated blood pressure measurement device were higher than photoplethysmography and correlations between both method were significant (r=0.886, r=0.844). Ankle brachial pressure index derived using automated blood pressure measurement have a better correlation with photoplethysmography method (r=0.622) than pulse palpation (r=0.255). The subject was considered to have peripheral arterial disease if either leg ABI was 0.9 or less. Peripheral arterial disease was more frequent when it was defined using photoplethysmography (13.8%) vs automated blood pressure measurement device (6.3%). The sensitivity of the automated blood pressure measurement is 32.4%, the specificity is 97.8% and the accuracy is 88.8% for peripheral arterial disease defined using photoplethysmography.
CONCLUSION
Automated blood pressure measurement was easier and quicker and less expensive as compared with photoplethysmography. Automated blood pressure measurement was not sensitive but more accurate as compared with pulse palpation. So we recommend that it be used on a routine screening basis of peripheral arterial disease in primary care.