Abstract:Objective To explore the effect of semi-Fowler's lateral position on arterial blood gas, extubation time, post- anesthesia care unit (PACU) discharge time, and complication in patients undergoing bariatric and metabolic surgery during the anesthesia recovery period. Methods Convenience sampling was used to select patients who underwent bariatric and metabolic surgery at Jiangsu Provincial People's Hospital from October 2024 to May 2025 as the study subjects. A total of 106 eligible patients were included and randomly divided into a control group and an experimental group, with 53 patients in each group. The control group received conventional PACU management, while the experimental group, in addition to conventional management, received semi-Fowler's lateral position management with the head of the bed elevated at 45° and lateral tilt at 60°-90°. Arterial blood gas parameters [partial pressure of arterial oxygen (PaO₂), partial pressure of arterial carbon dioxide (PaCO₂), pH, etc.], extubation time, PACU discharge time, and complication rates were compared between the two groups. Results Ultimately, 52 patients in the control group and 50 patients in the experimental group were included. There were significant between-group, time, and interaction effects for PaCO₂, base excess (BE), pH, and bicarbonate ion ( HCO₃^- ) (P<0.01). There was no time effect or interaction effect in PaO₂, but there was a significant between-group effect (P<0.05). There was no between-group effect in hematocrit (Hct), but the time effect and interaction effect were significant (P<0.01). Pairwise comparisons using the LSD-t test showed that, compared to the control group, the experimental group had significantly improved PaCO₂, BE, and HCO₃^- levels during post-extubation deoxygenation and at PACU discharge. The extubation time [ (32.42±13.07) min vs (43.79±13.55) min, t=4.311, P<0.01]and PACU discharge time [ (53.60±17.18) min vs (79.23±12.27) min, t=8.697, P<0.01]in the experimental group were significantly shorter than those in the control group, and comfort scores, systolic blood pressure, diastolic blood pressure, and heart rate at PACU discharge were significantly better in the experimental group (P<0.05). The incidence of hypoxemia in the control group was slightly higher than that in experimental group, but the difference was not statistically significant [32.69% (17/52) vs 16.00% (8/ 50), P=0.066]. However, the incidence of glossoptosis in the experimental group was significantly lower than that in the control group [6.00% (3/50) vs 21.15% (11/52), χ²=4.943, P=0.026]. Conclusion Semi-Fowler's lateral position management can effectively improve oxygenation, ventilation, and metabolic-related indicators, shorten anesthesia recovery time, and reduce the incidence of glossoptosis in patients undergoing bariatric and metabolic surgery during the anesthesia recovery period.