Incidence, Risk Factors, and Outcomes of Acute Kidney Injury in Major Burn Patients: A 7-Year Experience in Ramathibodi Hospital

Objective: To identify the incidence of acute kidney injury (AKI) in patients with major burn injuries within the first week of intensive care unit (ICU) admission at Ramathibodi Hospital and to identify risk factors associated with AKI. Materials and Methods: The present study was a retrospective observational study of the patients with major burn injuries in the burn intensive care unit (BICU) at Ramathibodi Hospital. All data were retrieved from the scanned medical records of the patients admitted to the BICU between January 1, 2016 and December 31, 2022. The patients were diagnosed and graded according to the Kidney Disease Improving Global Outcomes (KDIGO) recommendation. Independent risk factors associated with AKI were identified by multivariable logistic regression. Results: Eight of the 50 patients (16%) had AKI within the first week of admission. The baseline international normalized ratio (INR) level of 1.5 or greater was independently associated with AKI with an odds ratio (OR) of 32.42 (95% confidence interval [CI] 2.194 to 478.608). No independent risk factor was identified for 28-day mortality. Fluid balance in the first week had an area under receiver operating characteristics (ROC) of 0.856 (95% CI 0.747 to 0.964) to diagnose 28-day mortality. A cutoff point of 22,761 mL or more provided a sensitivity of 90.91% and a specificity of 61.54%. Conclusion: The incidence of AKI in the first seven days of BICU admission was 16%. Coagulopathy, defined as INR of 1.5 or greater, was identified as an independent risk factor associated with early AKI in patients with major burns. Utilizing a simple value of INR could be a practical way to identify patients with major burns that may require further workup. Furthermore, the fluid balance cutoff point could be used as a warning signal of high risk for mortality during a weekly review of patients’ clinical rounds.