Determination of the incidence of hyperoxia and the effectiveness of oxygen reserve index guided FiO2 titration in preventing hyperoxia. 

Abstract Background Although pulse oximetry technology, which is considered the standard of care to ensure optimum oxygenation, is indispensable in clinical practice, especially in the detection of hypoxemia, it has some limitations in the detection of hyperoxemia. Oxygen Reserve Index (ORi™, Masimo Corp., Irvine, CA, USA) can provide clinicians with a crucial pathway in detecting and preventing hyperoxia, noninvasively. Our aim in this study is to determine the hyperoxia detection ability of ORi and to investigate the effectiveness of ORi and SpO2-guided FiO2 titration in preventing hyperoxia. Material and Methods In this prospective, randomized study, patients who would undergo major abdominal surgery were divided into two groups as the control group and the SpO2 + ORi group. In the SpO2 + ORi group, FiO2 titration was performed by trying to maintain the ORi between 0.00 and 95%<SpO2 ≤ 98%. In both groups, patients' SpO2, ORi, PaO2, PaCO2, PEEP, FiO2, and hemodynamic parameter values were recorded before induction, 10 minutes after intubation, and every hour during the operation. Results In the Ori + SpO2 group, a high level of positive linear relationship of 75.8% was found between PaO2 and ORI (p < 0.001). While moderate hyperoxia was observed in six people in the control group, it was not observed in the ORI + SpO2 group (3rd hour). In ORI + SpO2 group with FiO2 titration, PaO2 values decreased significantly over time (p < 0.001). The optimal cut-off ORi value, which can detect PaO2 ≥ 150 mmHg, was found to be 0.23 (Sensitivity = 100% Selectivity = 72.2%). Conclusion The combined use of SpO2 and ORi has been demonstrated to successfully guide FiO2 titration for optimal oxygenation and reduce hyperoxia.