[Unreliability of pulse oximetry in hypothermic children after cardiovascular surgery with deep hypothermic circulation]. / Inattendibilità del pulse oximetry in lattanti ipotermici dopo interventi di cardiochirurgia in ipotermia profonda.

BACKGROUND: The aim of the study was to evaluate the accuracy of oxygen saturation with the pulse oximeter (SpO2) in children undergoing cardiovascular surgery with deep hypothermic circulation. METHODS: The SpO2 values measured at the hand and at the foot were compared in 50 patients with the arterial oxygen saturation (SaO2) measured with the oximeter. A variance value between the two measurements less than 3% was considered as a reliable measurement, and the precision of the measurement was defined as the standard deviation of the variability. RESULTS: For skin temperature between 35 and 28 C grade, and for core temperature more than 34 grade, the SpO2 is a reliable measurement of the SaO2; for skin temperature less than 28 grade and core temperature less than 34 grade the SpO2 do not correspond the SaO2. CONCLUSIONS: The variability and the precision of the measurements are not affected the position of the probe (hand or foot).