Semirecumbent Positioning in Anesthesia Recovery Reduces Postoperative Hypoxemia Risk: JAMA

The randomized clinical trial that included 700 adults undergoing laparoscopic upper abdominal surgery (LUAS) revealed that a 30° semirecumbent position during recovery from anesthesia may help prevent the development of postoperative hypoxemia.

"A 30° semirecumbent position during recovery from anesthesia lowered the incidence of postoperative hypoxemia from 47% in a supine position to 32%," the researchers reported in JAMA Network Open. 

Postoperative hypoxemia, characterized by low oxygen levels in the blood after surgery, is a common and concerning complication that can lead to respiratory distress and prolonged hospital stays. Traditional recovery practices often involve patients lying flat, which may contribute to impaired lung function and exacerbate oxygenation issues.

Despite the widespread use of a semirecumbent position (SRP) in reducing postoperative hypoxemia during anesthesia emergence, there is no clarity on its efficacy. Considering this, Xinghe Wang, Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, China, and colleagues aimed to determine the differences in postoperative hypoxemia between patients in an SRP and a supine position.

For this purpose, the researchers performed a randomized clinical trial at a tertiary hospital in China between 2021 and 2022. It enrolled patients scheduled to undergo laparoscopic upper abdominal surgery under general anesthesia. Study recruitment and follow-up are complete.

Patients were randomized to one of the following positions at the operation's end until leaving the post-anesthesia care unit: supine (group S), 15° SRP (group F), or 30° SRP (group T).

The primary outcome was the postoperative hypoxemia incidence in the post-anesthesia care unit. Severe hypoxemia was also evaluated.

The study led to the following findings:

• Out of 700 patients (52.0% men; mean age, 47.8 years), 233 were randomized to group S (54.1% men; mean age, 48.2 years), 233 to group F (52.4% men; mean age, 48.1 years), and 234 to group T (50.4% women; mean age, 47.2 years).
• Postoperative hypoxemia differed significantly among the three groups (group S, 46.8%; group F, 45.1%; group T, 32.5%). This difference was statistically significant for groups T versus S (risk ratio [RR], 0.69) and groups T vs F (RR, 0.72), but not for groups F versus S (RR, 0.96).
• Severe hypoxemia also differed among the three groups (group S, 26.2%; group F, 22.7%; group T, 15.4%). This difference was statistically significant for groups T vs S (RR, 0.59).

The findings showed that using a 30-degree SRP during anesthesia emergence notably decreased the incidence of postoperative hypoxemia in patients undergoing LUAS compared to those in the supine position. Additionally, it shortened the duration of stay in the post-anesthesia care unit (PACU), led to fewer instances of airway rescue and coughing, and improved overall PACU operational efficiency.

Reference:

Wang X, Guo K, Sun J, et al. Semirecumbent Positioning During Anesthesia Recovery and Postoperative Hypoxemia: A Randomized Clinical Trial. JAMA Netw Open. 2024;7(6):e2416797. doi:10.1001/jamanetworkopen.2024.16797