Post-operative Nausea and Vomiting at Mulago Hospital

Background : Postoperative nausea and vomiting (PONV) are among the most common adverse events related to surgery and anaesthesia and despite modern anaesthetic and surgical techniques the incidence of PONV remains at 20-30%. The aim of this study was to determine the prevalence and factors associated with postoperative nausea and vomiting. Methods : This was a prospective study. Precoded data were analyzed and for categorical variables data were summarized as proportions and presented using tables, histograms and pie charts. Continuous variables were analyzed by separating means using independent samples T-test. In the univariate analysis, Odds ratio together with 95% confidence interval was calculated to test for the association between the possible risk factors and outcome variables. Multivariate analysis was done using logistic regression model to determine prognostic factors of postoperative nausea and vomiting. Results : One hundred eighty two patients aged 10 years and above met the inclusion criteria. They had fasted 6 hours prior to the operation and undergone both general anaesthesia and surgery. Patients who had medical and surgical conditions that led to nausea and vomiting were excluded. 53% of the patients were males and 43% were females. The prevalence of PONV was 40.7% within 24 hours after surgery. Factors that were statistically significantly (p value < 0.05) associated with PONV following univariate analysis included : age group 20 to 30 years, female gender, history of PONV, intra-operative use of Pethidine, type of operation (orthopaedic surgery) and postoperative use of Pethidine. Independent predictors of PONV include; age group of 20 to 30 years, history of PONV, and the type of operation. Conclusion : Predictors of PONV within 24 hours include age group of 20 to 30 years, history of PONV and the orthopaedic surgery