Comparison of Effects of Propofol and Sevoflurane Used in Maintenance of General Anaesthesia on Post-Operative Nausea and Vomiting - A Prospective Observational Study

BACKGROUND Post-operative nausea and vomiting is a complication of general anaesthesia but can also be seen less commonly in regional anaesthesia. The uneasiness and discomfort associated with it can make the post-operative period eventful. We conducted this study to evaluate if sevoflurane and propofol used in maintenance of anaesthesia have any influence on post-operative nausea and vomiting. METHODS We included 64 patients in this prospective observational study who were undergoing elective otorhinolaryngology surgery belonging to American Society of Anaesthesiologist (ASA) PS I and II. After induction of general anaesthesia and endotracheal intubation, Group P received propofol at 100 - 200 mcg / kg / hr and group S received sevoflurane as maintenance anaesthetics agent at 1.5 - 2 %. All the patients were given ondansetron intravenously in the intra-operative period. Anaesthetic agents used for maintenance was stopped at the end of the surgery and patients were extubated and shifted to post-operative care unit. Patients were assessed for any occurrence of post-operative nausea and vomiting after extubation for 24 hours. RESULTS There were 2 (6.25 %) patients in the propofol group and 12 (37.5 %) patients in the sevoflurane group who had post-operative nausea and vomiting in the first hour. The difference in the nausea and vomiting between the groups was statistically significant with (P value of 0.0046) higher incidence in sevoflurane group. All the patients who had nausea and vomiting were treated with dexamethasone. When the patients were reassessed after four hours, five patients had nausea in sevoflurane group after four hours, which was treated with metoclopramide or Ondansetron. After six hours, none of the patients had nausea or vomiting. CONCLUSIONS The incidence of post-operative nausea and vomiting was lesser in the propofol group compared to sevoflurane group.