Use of Pulse Oximeter as a Tool to Detect Peripheral Arterial Disease: A Cross-sectional Study in a Tertiary Care Center

A BSTRACT Use of pulse oximeter as a tool to detect peripheral arterial disease. A cross-sectional study in a tertiary care center. Aims and Objectives: To evaluate the utility of pulse oximeter (index test) as a diagnostic test to detect peripheral arterial disease (PAD) by comparing it with the standard diagnostic test, that is, arterial Doppler ultrasonography. Secondary Objective: To evaluate the efficacy of ankle brachial pressure index (ABPI) in detecting PAD. Materials and Methods: Patients of age 40 years or older with symptoms of PAD or asymptomatic patients with risk factors for peripheral vascular disease had pulse oximeter readings of upper and lower limbs. A decrease in pulse oximeter reading of 2% in the lower limb compared to the upper limb reading was considered positive. The patients then underwent ABPI measurement with a handheld Doppler device, arterial Doppler ultrasonography of the lower limb was conducted, and the results of each test were compared. Results: The values obtained by pulse oximeter measurement had a sensitivity of 64.4% (95% CI 56.7%-71.4%), specificity of 75% (95% CI 47.6%-92.7%), PPV and NPV of 96.6% (95% CI 92.2%-98.5%) and 16.2% (95% CI 12.04%-21.48%) respectively, with a P value of 0.002 and accuracy of 65.2%, whereas values obtained by ABPI had a sensitivity of 72.4% (95% CI 65.5%-79.1%), specificity of 50% (95% CI 24.6%-75.3%), PPV and NPV of 94% (95% CI 90.6%-96.3%) and 14.3% (95% CI 8.8%-22.3%) respectively, with a P value 0.06, and an accuracy of 70%. Conclusion: Pulse oximeter can be used as a tool for the detection of PAD with considerable accuracy.