Accuracy of three pulse oximeters at low cardiac index and peripheral temperature.

Abstract

To assess the ability of three different pulse oximeters to give reliable readings during poor cardiac index and peripheral temperature states as compared with normal cardiac index and peripheral temperature states in the same patients. The accuracy of the oximeters was tested against a blood oximeter (measuring actual arterial oxygen saturation) during four different physiologic situations: normal and low cardiac index; normal and low peripheral temperature. Thirty-three open-heart surgery patients, mean age 52 yrs, were studied immediately after open-heart surgery and in the ICU after the operation. Saturation display in different oximeters was equally reliable in situations of poor cardiac index (less than or equal to 2.2 L/min.m2) and low peripheral temperature (less than or equal to 28 degrees C), as in control situations. However, there were statistically significant differences between the equipment. The heart rate display was also reliable in these situations. Clinically reliable saturation and heart rate readings were obtained when cardiac output and peripheral temperature were low.