The Accuracy of Pulse Oximeter in Predicting the Arterial Oxygen Saturation

ABSTRACT

We studied 21 neonates who required mechanical ventilation during study period in NICU OF Il Sin Christian Hospital with diagosis of prematurity, IRDS, pneumothorax and diaphragmatic hernia to evaluate the accuracy of pulse oximeter in predicting the arterial oxygen saturtion, hypoxia and hyperoxemia. We also studied whether the changes of birth weight, hematocrit, blood pressure and body temperature affect the accuracy of pulse oximeter. The results are 1) Linear regression analysis revealed a close correlation between in vivo pulse oximeter readings and in vitro SaO2 measurements in patients (Y=0.008X+12.34, r=0.946) 2) The changes of birth weight, hematocrit, blood pressure and body temperature did not affect the accuracy of pulse oximeter. 3) SpO2-PaO2 relationship was similar to the SsO2-PaO2 relationship. 4) When Nellcor N-100 pulse oximeter was setted at alarm limit 96% to avoid hyperoxemia, it identified 16 of 22 hyperoxemic instances (sensitivity 73%) and alarmed falsely in 48 of 92 nonhyperoxemic instances (specificity 59%).