Anaesthetic profile and perioperative mobi-mortality according to renal function in patients undergoing urgent and elective surgery at Monkole Hospital, Kinshasa: a cross-sectional study

Abstract

Background: Chronic kidney disease (CKD) increases perioperative risk through metabolic, cardiovascular, and hematologic disturbances that complicate anaesthetic management. Evidence from sub-Saharan Africa on surgical outcomes across CKD stages is limited.

Objective: To describe anaesthetic practices and assess perioperative morbidity and mortality in CKD patients undergoing surgery at Monkole Hospital, Kinshasa.

Methods: This retrospective cross-sectional study included adult CKD patients who underwent urgent or elective surgery between February 2018 and December 2024. Renal function was classified using the CKD-EPI 2021 equation into GFR categories G1–G5. Outcomes included intraoperative incidents, perioperative complications, transfusion requirements, opioid use, and in-hospital mortality. Multivariate logistic regression identified predictors of adverse outcomes, comparing patients with GFR < 60 and ≥60 mL/min/1.73 m2.

Results: Among 418 patients, 48.1% were G3, 24.6% G2, and 15.3% G1. Complications and mortality rose with declining renal function. Patients with GFR < 60 mL/min/1.73 m² had higher mortality than those with GFR ≥ 60 (11.2% vs. 5.4%). After adjustment, GFR < 60 remained independently associated with mortality (OR 2.61, 95% CI 1.01–6.71).

Conclusion: Reduced renal function independently predicted increased perioperative mortality, highlighting the need for improved risk stratification in CKD patients.