Comparative Analysis of Arterial Oxygen Saturations During Exercise by Pulse Oximetry, Photometric Measurements, and Calculation Procedures

Abstract

Pulse oximetry allows non-invasive monitoring of arterial oxygen saturation (SO₂). To study the validity of pulse oximetry, comparative measurements were performed. During exhaustion limited exercise S0₂-values measured by pulse oximetry (SO₂puls), calculated SO₂-values (algorithms of Kelman, Severinghaus, and Siggaard-Andersen - SO₂calc), and as “golden standard” photometric measured SO₂-values (SO₂meas) were compared. Fourteen triathletes performed a stepwise cycling exericse test in the supine position. SO₂calc was determined on the basis of capillary actual blood gas values. SO₂puls was measured continuously with a finger probe attached to the second finger. The SO₂puls- and SO₂calc-values differed from the SO₂meas-values (p < 0.05); however, the differences were of no clinical relevance. Performing linear regression analysis, only SO₂puls correlated significantly (r = 0.47, p < 0.001) with SO₂meas. Pulse oximetry is able to replace invasive measurements of arterial oxygen saturation in athletes. It is superior to SO₂-calculations and permits reliable, valid and non-invasive continuous monitoring of SO₂.

Key words

pulse oximetry - oxygen saturation - ergometry - triathlon