Effect of Hypothermia on the Oxygen Saturation Readings with Pulse Oximeter
Published Online: Jul 24, 2015
Abstract
Although pulse oximetry is a potentially useful diagnostic tool under anesthesia. there are concerns regarding its reliability for measuring oxygen saturation (SpO2 ; arterial oxygen saturation by pulse oxymeter) in hypothermic or low perfusion states. To test pulse oximeter reliability under hypothermic condition 30 data from 14 patients were collected.
Subjects were divided into group I which was as body temperature>36℃ and group 2 which was body temperature <36℃.
The results were as follows:
1) There were no differences between group I and group 2 in the SaO2(arterial oxygen saturation by blood gas analyzer) and SpO2.
2) The SpO2 in group I was underestimated by 1.20±0.85% than SaO2 in group 1(P<0.001).
3) The SpO2 in group 2 was underestimated by 0.60±1.03% than SaO2 in group 2(p<0.05).
Although the SpO2 was underestimated under hypothermic condition, the pulse oximeter with expired CO2 tension monitor decreased the frequent invasive arterial blood gas analysis. And it was useful tool for the detection of the hypoxia which is most commom cause of preventable anesthesia related death.