Sensitivity and specificity of pulse oximetry for identification of peripheral artery disease: a systematic review

BACKGROUND: Lower limb peripheral artery disease (PAD) is associated with poor outcomes including ulceration, gangrene, amputations, and mortality. Clinicians therefore routinely perform point-of-care tests in high-risk populations to identify PAD and subsequently implement cardiovascular management and appropriate interventions. Pulse oximetry has been suggested as a useful adjunct test for identifying PAD. OBJECTIVE: The aim of this systematic review was to determine the sensitivity and specificity of pulse oximetry in the lower limb for identifying PAD. METHODS: MEDLINE, EMBASE, and CINAHL were searched up until January 10, 2023, to identify studies of sensitivity and specificity of pulse oximetry that used criterion standard diagnostic imaging as a reference standard. Two authors screened articles for inclusion and appraised quality of included studies using the Quality Appraisal for Diagnostic Accuracy Studies, version 2. RESULTS: A total of 6371 records were screened, and 4 were included. The included studies had a total of 471 participants, with an age range of 41 to 80.6 years. All studies were cross-sectional and conducted in hospital settings. Sensitivity values for pulse oximetry compared with diagnostic imaging in identifying PAD ranged from 44% to 76%, and specificity values ranged from 85% to 96%. There was no consensus regarding measurement techniques and diagnostic thresholds for pulse oximetry, which precluded meta-analysis. CONCLUSIONS: There is currently inadequate evidence to support the use of pulse oximetry for identifying PAD. Current evidence suggests that pulse oximetry has low levels of sensitivity and is therefore likely to miss PAD when it is present.