2024 FSA Podium and Poster Abstracts
P043: IMPACT OF OSA STATUS ON TIMING OF POSTOPERATIVE DESATURATION AMONG BARIATRIC SURGERY PATIENTS
Naveen Perisetla, BS1; Jose Malavet, BS1; Christopher Popiolek, BS1; Ashley Mooney, MD2; Peter Wu, MD3; Jeffrey Weiss, DO3; Maha Balouch, CCRP3; Enrico Camporesi, MD3; John Hodgson, MD3; 1University of South Florida Morsani College of Medicine; 2Tampa General Hospital; 3TEAMHealth Anesthesia
Background: Bariatric surgery patients are at increased risk of developing postoperative respiratory depression. Among these patients, obstructive sleep apnea (OSA) is a common comorbidity. While OSA has been associated with postoperative respiratory depression, there is scant evidence regarding the exact timing of these desaturation events. In this study, we determined the impact of OSA status on postoperative exposure duration to a wide range of SpO2 levels (80-95%) among bariatric surgery patients. In addition, we also investigated the distribution of desaturation events within the postoperative period.
Methods: Data were collected from 195 patients who had bariatric surgery at our hospital between June 2022 and December 2023 (IRB # 00036836). Patients were continuously monitored during the postoperative period with Masimo Rad 97 and TRACE software until the next morning. Exposure duration to four SpO2 ranges (<80%, 80-84%, 85-89%, 90-95%) were then compiled. A desaturation event was defined as a drop in SpO2 by 3% for a minimum duration of 30 seconds or a drop to SpO2 < 89%. We divided postoperative events into 2-hour intervals, during which events were recorded. We conducted descriptive statistics, Pearson chi-square tests, and student’s t-test, to compare OSA vs non-OSA patients.
Results: Patients were mainly female (88.7%) with a mean age of 44.5 years (SD: 11.5). On average, patients were monitored for 871 minutes (14.5 hours) after discharge from PACU. One hundred and twenty-six patients (64.6%) were OSA positive, and 69 (35.4%) were OSA negative. There was no significant difference in monitor duration between the two groups (872 minutes vs. 869 minutes, p=0.934). Patients with OSA received slightly higher intraoperative narcotics (only by 1.45 MME, total), but received similar amounts of postoperative narcotics. Exposure duration to the 80-84%, 85-89%, and 90-95% SpO2 ranges was significantly higher among patients with OSA. Both groups of patients had minimal exposure to SpO2 ranges below 80% (see Table). Patients with OSA overall showed significantly more desaturation events than those without OSA (9.06 vs. 2.16, p=0.010). When dividing the postoperative monitoring period into 2-hour intervals, patients with OSA had most of their desaturation events within the first 6 hours after PACU discharge, though some later differences were also significant (see Figure). Patients without OSA had no clear temporal distribution of their desaturation events.
Conclusion: Among bariatric surgery patients, the presence of OSA is significantly associated with postoperative desaturation events, though medications with narcotics were minimized. Particular attention should be paid to the postoperative period as a time of desaturation among patients with OSA.
