Utility of digital pulse oximetry in the screening of lower extremity arterial disease

Purpose:The aim of this study was to evaluate screening methods in the lower extremities by measurement of the digital pulse oximetry (oxygen percent saturation [SpO2]) of toes for peripheral arterial disease (PAD).Methods: A prospective study was performed among 49 patients (98 limbs) with lower extremity arterial occlusive disease.We attempted to measure the ankle-brachial index (ABI), digital pulse oximetry (SpO2), and computerized tomographic angiography (CTA).Patients were divided into three groups by the traditional Fontaine classification system by symptom and CTA criteria: 1) Critical limb ischemia (Fontaine III and IV), 2) Claudication; (Fontaine II), and 3) asymptomatic limbs (Fontaine I).Results: The sensitivity, specificity, positive and negative predictive values between active treatment groups (group I and II; endovascular and open surgery) and conservative group (group III) are all statistically significant.ABI; 55.09%, 94%, 96.7%, 39.02% (R = 12.54, P ＜ 0.000) SpO2; 87.06%, 87.8%, 84.3%, 90% (R = 40.11,P ＜ 0.000).Pre-SpO2 and pre-ABI all show statistically significant correlation in group I vs. group II, symptomatic PAD (group I and II) vs. asymptomatic PAD (group III), and the total PAD comparison.The Pearson's correlation coefficient between SpO2 and ABI all show significant correlation in group II.Pre-SpO2 vs. Pre-ABI show strong positive correlation except asymptomatic group (group III).Conclusion: Digital pulse oximetry can be a useful, simple, noninvasive screening device as well as ABI in PAD.