Magnitude of early postoperative hypoxemia and its associated factors among adult patients who undergo emergency surgery under general anesthesia at Jimma Medical Center, Jimma, Southwest Ethiopia, 2021: a prospective observational study

Abstract Purpose Emergency surgical procedures involve considerable risks. Among these, early postoperative hypoxemia (EPH) is a frequent anesthetic complication in the post-anesthetic care unit (PACU). There is a great concern for EPH among health professionals, specifically, those providing emergency surgery during the nighttime. This raised anesthesia-ended time-related risk of EPH question. Thus, this study aimed to determine the magnitude of EPH and its associated factors among adult patients who undergo emergency surgery under general anesthesia. Methods A prospective observational study through a consecutive sampling technique was conducted. Binary logistic regression analysis was used to identify associated risk factors. All variables that were found statistically significant on bivariable analysis were entered into a multivariable logistic regression analysis. Result Of 352 patients who had undergone emergency surgery, 149 (42.3%) patients developed EPH. Factors significantly associated with EPH were anesthesia ended during nighttime (AOR = 1.76, 95%CI [1.01, 3.05], p = 0.045), ASA III (AOR = 12.35, 95%CI: [4.5, 34.02], p ≤ 0.001), age greater than 55 (AOR = 3.2, 95%CI: [1.7, 5.91], p ≤ 0.001), surgery duration greater than 2 h (AOR = 2.012, 95%CI: [1.2, 3.51], p = 0.014), hypotension (AOR = 10.3, 95%CI: [2.4, 44.16], p = 0.002), muscular strength score zero (AOR = 2.944, 95%CI: [1.8, 4.82], p ≤ 0.001), and preoperative oxygen saturation less than 95% (AOR = 2.371, 95%CI: [1.35,4.16], p = 0.003). Conclusion The magnitude of EPH among patients who have undergone emergency surgery was high and thus recommended that oxygen should be provided timely to decrease it. Identified risk factors were night-time ended anesthesia, ASA III, age greater than 55, surgery duration greater than 2 h, hypotension, muscular strength score zero, and preoperative oxygen saturation less than 95%. This study found anesthesia ended during early morning favors early morning early postoperative hypoxemia (EMEPH). To avert EMEPH, the anesthetist should avoid factors that favor the circadian rhythm of the lung-based early morning anesthesia augmented EPH.