• S K Powers, S Dodd, J Freeman, G D Ayers, H Samson, and T McKnight.
• Department of Exercise and Sport Sciences, University of Florida, Gainesville 32611.
• J. Appl. Physiol. 1989 Jul 1;67(1):300-4.

AbstractThe accuracy of two pulse oximeters (Ohmeda 3700 and Biox IIa) was evaluated during cycle ergometer incremental exercise in 10 healthy subjects. The exercise protocol began at 30 W with the power output being increased 15 W.min-1 until volitional fatigue. Ear and finger probe pulse oximetry measurements of available hemoglobin (%Spo2) were compared with arterial oxyhemoglobin fraction of total hemoglobin (%HbO2) measured directly from arterial blood samples using a CO-oximeter. To provide a wide range of %HbO2 values, four subjects exercised under hypoxic conditions [inspired partial pressure of O2 (PIo2) = 107 Torr], while the remaining six subjects exercised under normoxic conditions (PIo2 = 150 Torr). Because carboxyhemoglobin (HbCO) or methemoglobin (MetHb) is not measured by pulse oximeters, %HbO2 was corrected for HbCO and MetHb and expressed as percent arterial O2 saturation of available Hb (%Sao2). Small and insignificant differences (P greater than 0.05) existed between SpO2 (all 3 instruments) and %SaO2 at the lowest work rate and the highest power output achieved. Regression analyses of %SpO2 vs. %SaO2 produced correlation coefficients of r = 0.82 [standard error of the estimate [(SEE) = 1.79], r = 0.89 (SEE = 1.48), and r = 0.93 (SEE = 1.14) for the Biox IIa, Ohmeda 3700 (ear), and the Ohmeda 3700 (finger) pulse oximeters, respectively. We conclude that pulse oximetry, within the above limits of accuracy, is useful in estimating %SaO2 during exercise in healthy subjects.

11 keywords...

hide…