Perioperative changes in oxygen saturation after ambulatory laparoscopic cholecystectomy: a retrospective analysis

In the ambulatory surgical setting, patients may present with grossly abnormal oxygen saturation (Spo2) readings that, along with other disease pathology, make referral to an inpatient facility a straightforward decision. Patients presenting with unexplained slightly abnormal Spo2 readings might make evaluation as an appropriate candidate for the ambulatory setting more problematic. Little guidance is provided for these scenarios in current consensus documents, and minimal data exist regarding preoperative baseline Spo2 readings as a predictor for postoperative Spo2 readings after undergoing general anesthesia and surgery in the ambulatory care setting. A retrospective analysis was performed of all laparoscopic cholecystectomies performed at a freestanding ambulatory surgery center during 2011 (n = 56). Multiple linear regression analysis was performed to establish predictors for variability in baseline Spo2. Wilcoxon tests were used to compare preoperative baseline Spo2 readings with readings taken at discharge. Increased patient age was the only statistically significant predictor of lower baseline Spo2 levels, although no statistically significant decrease in Spo2 was found at discharge in patients above 60 years old. Males, patients who smoke, and patients whose body mass index exceeded 30 kg/m2 all demonstrated statistically significant decreases in Spo2 values at discharge home (Z = -1.947, -1.807, -1.75, P < .05).