Predictors of mortality among non-traumatic critically ill patients with electrolyte imbalances attending a Ugandan regional referral hospital Emergency Department

Abstract

Background: Electrolyte imbalances are common among critically ill patients and strongly influence outcomes, and yet data from sub-Saharan Africa remain limited. This study aimed to determine the prevalence, severity of electrolyte imbalances and predictors of 14-day mortality among non-traumatic critically ill patients in a Ugandan tertiary hospital Emergency Department (ED). Methodology: We conducted a four-month prospective cohort study in 2023 on non-trauma patients at Mbarara Regional Referral Hospital ED. Consecutive non-traumatic adults with a Modified Early Warning Score ≥5 or a single parameter score of 3 were enrolled. Serum sodium, potassium and chloride were measured at admission. Patients were followed for 14-day mortality. Multivariate Cox regression was used to identify independent predictors of mortality using Stata version 17.0. Results: Among the 400 patients enrolled, 45% (median age 59 years; 64% male) had electrolyte imbalances. The 14-day mortality was 59.9%, with most deaths occurring within the first three days. More than three-quarters of patients had multiple electrolyte imbalances, of which hyponatraemia, hyperchloraemia, and hypokalaemia was the most common. After adjustment, independent predictors of increased mortality were referral from other facilities (AHR 2.4, 95% CI: 1.1-5.3) in addition to heart failure and a history of alcohol use. Specialist involvement (AHR 0.5, 95% CI: 0.3-0.9) was found to be protective in addition to pre-referral electrolyte correction and ward admission from the ED. Conclusion: Electrolyte imbalances affect over half of critically ill non-trauma ED patients in Uganda and are associated with high early mortality. Heart failure, alcohol use, and inter-facility referral predict worse outcomes, while targeted pre-referral electrolyte correction, early specialist input and prompt ED disposition are strongly protective. These findings highlight actionable priorities for improving emergency care in similar low-resource settings.