The incidence and risk factors of post-surgical AKI in a low resource setting: a prospective cohort study

Post-surgical acute kidney injury (AKI) accounts for as much as a third of hospital acquired AKI. Post-surgical AKI is underreported in sub-Saharan Africa and it is associated with a longer hospital stay, a higher rate of readmission post-discharge, increased inpatient mortality, 1-year mortality, chronic kidney disease, and end-stage renal disease. The aim of this study is to determine the incidence of post-surgical AKI as well as to evaluate risk factors for post-surgical AKI. The study was a prospective cohort study carried out in Delta State University Teaching Hospital Oghara, Delta State. A total of seventy-nine participants billed to have either elective or emergency major abdominal surgery were recruited. Post-surgical AKI was diagnosed using the KDIGO serum creatinine criterion. Continuous variables were analysed using mean and median and were compared using the student T-test and Mann Whitney U test. Categorical variables were presented as frequencies and were compared using the chi-square test, Yates correction test and the fisher’s exact test as appropriate. The level of statistical significance was defined at p ≤ 0.05, at 95% confidence interval. Seventy-three participants were evaluated in this study with the modal age of 51–60 years and a median age of 44 years. The incidence of post –surgical AKI was 20.5%, more so patients with AKI were most likely to have a higher BMI (p < 0.0001), waist to hip ratio (p = 0.002), higher pulse rate and respiratory rate (p < 0.0001), higher temperature (p = 0.002), higher Revised cardiac risk index score (p = 0.02), higher fasting blood sugar (p = 0.001), longer duration of surgery, higher intraoperative blood loss(p = 0.04) and duration of anaesthesia (p = 0.001). The incidence of post-surgical AKI is high in low resource settings and measures can be taken to reduce the incidence and improve outcomes in the those with established risk factors.