Intraoperative and Postoperative Factors Tend to Decrease in Oxygen Saturation in Postanesthesia Care Unit

  We aimed to investigate intraoperative and postoperative factors tend to decrease in oxygen saturation in postanesthesia care unit (PACU). In this observational study, body temperature, systolic and diastolic blood pressure, mean arterial pressure, respiratory rate, pulse rate, O2 saturation, needs for using nitrous oxide (N2O), needs for positive end-expiratory pressure (PEEP), liquid volume used for each patients during surgery, mean patient's blood loss, type of blood products used during surgery, snoring, type of anesthetic medications, time duration of surgery, and site of operation in patient's body were recorded during and after operation. Patients were divided into two groups that experienced oxygen desaturation and those did not. All the variables were compared between the two groups. Findings: From 500 patients participated in this study, 50 participants (10%) experienced oxygen desaturation, while 445 cases (89%) did not, and 5 patients (1%) had uncertain condition for oxygen saturation. Significantly higher variables in the group with oxygen desaturation were as pulse rate during the surgery (P = 0.009), mean liquid volume (P = 0.029), pain and its severity (P = 0.001 for both), and snoring (P = 0.020). There was a significant relation between presence of oxygen desaturation and having operation on thorax (60%), upper abdomen (40%), and spine (39%) (P = 0.001). Pulse rate during the surgery, liquid volume used during surgery, using N2O, not using PEEP, pain and its severity, and snoring in PACU are associated with experiencing oxygen desaturation.