Effect of intraoperative different oxygen concentrations on nausea and vomiting in morbid obesity

Postoperative nausea and vomiting (POBK) is a common problem due to many reasons, especially in the first two hours after the surgery. In this study, the effect of different intraoperative oxygen concentrations on nausea and vomiting in morbidly obese patients was investigated retrospectively. After approval of the ethics committee, 206 patients who underwent bariatric laparoscopic surgery in 2018 were included in the study. The patients were divided into two groups depending on the use of oxygen at different concentrations. Those given 30% oxygen (n=87) were determined as group 30 and those given 70% oxygen (n=119) were determined as group 70. Demographic data of patients, body mass index (BMI), ASA score, hemodynamic parameters and anesthetic agents used, Apfel score, VAS score, PONV score, early (first 2 h.) and late period (2-24.h) the amount of antiemetics performed and the period of discharge were recorded. There was no difference between the groups in anesthetic drugs used and demographic data of the patients. The post-operative nausea-vomiting score of the patients was compared between the two groups and group 30/70 - 29/66 patients had no nausea and vomiting. Group 30/70 – 37/34 patients had nausea, group 30/70 - 17/18 patients had gag reflex-no vomiting, group 30/70 - 4/1 patients had vomiting. The difference between the groups was statistically significant. The difference between group 30 and group 70 in the amount of metoclopramide performed in the PACU (Post Anesthesia Care Unit) was statistically significant. No statistically significant difference was found between the two groups in the first 2-24 hours of rescue antiemetic. Group 70 had a shorter discharge time and this difference was statistically significant. Laparoscopic bariatric surgery is a high risk for postoperative nausea and vomiting. Oxygen therapy is thought to improve intestine perfusion and reduce postoperative nausea and vomiting. In our study, we found that intraoperative high oxygen concentration in morbidly obese patients undergoing laparoscopic bariatric surgery may reduce nausea and vomiting. The inexpensive and in this concentration possible side effects of oxygen are clinically insignificant, combined with effective antiemetic prophylaxis for patient undergoing laparoscopic bariatric surgery with high risk factors for postoperative nausea and vomiting may reduce the cost of postoperative antiemetic treatment and increase patient comfort while improving early patient discharge. Keywords: Morbid obesity, intraoperative oxygen concentration, postoperative nausea and vomiting