Incidence and Risk Factors of Acute Kidney Injury After Emergency Laparotomy at Kenyatta National Hospital

Abstract

Background: Acute kidney injury (AKI) is one of the most under-diagnosed post-operative complications and yet associated with increased morbidity and mortality. It is influenced by both patient and procedural factors. Study design: This was a prospective observational cohort study. Objective: To establish the incidence and risk factors of acute kidney injury in patients undergoing emergency laparotomy at Kenyatta National Hospital. Methodology: Convenience sampling was used to recruit 201 adults requiring emergency laparotomy and who met the inclusion criteria. The patients’ biodata and pre-determined physiological parameters were captured before, during and after surgery. Data collected was entered into Microsoft Excel, and thereafter exported to SPSS version 23 for analysis. The incidence of AKI was reported as a proportion, while the AKI stage was determined and reported as frequencies and proportions. Univariate analysis of the risk factors was done via chi-square tests, and the statistically significant factors were subjected to multivariate analysis with the use of logistic regression. Odds ratio, as well as relative risk with their 95% interval of confidence, were reported where applicable. All statistical tests were considered significant if the p-value was less than 0.05. RESULTS: The mean age of the patients was 40.1 (SD 15.8) years, with a male a notable male predominance. The overall incidence of AKI in this study was 18.4%, with a 10%, 11.4% and 8.5% prevalence of AKI at 12, 24 and 48 hours after surgery. Age >60 years, diabetes mellitus, hypertension, duration of anaesthesia >3 hours and requirement for blood transfusion were found to be the risk factors of AKI in this study. CONCLUSION: Patients with advanced age, pre-existing diabetes mellitus and hypertension, those undergoing major surgery and who receive Peri-operative red cell transfusion are at increased risk of developing post-operative AKI. Thus, they require close monitoring and early institution of renal protective strategies.