TO ASSESS THE EFFECTS OF DURATION OF CARDIOPULMONARY BYPASS ON POST-OPERATIVE RENAL FUNCTION

Abstract

Background: Cardiopulmonary bypass (CPB) is essential for many cardiac surgeries, yet its physiological impact on renal function remains a persistent clinical concern. Prolonged exposure to extracorporeal circulation can increase renal stress due to altered perfusion, inflammatory activation, and hemodynamic fluctuations. Understanding how CPB duration influences early postoperative renal markers is crucial for preventing complications such as acute kidney injury and ensuring better recovery outcomes for cardiac patients.

Objective: To evaluate the association between CPB duration and postoperative renal function among adult cardiac surgery patients.

Methods: A total of 109 patients undergoing cardiac surgery with CPB were included. Renal parameters were recorded after the first 24 postoperative hours in the ICU. The primary variables measured were CPB duration, serum creatinine, blood urea levels, and urine output. Data analysis was performed using SPSS version 23. Mean values and standard deviations were calculated for all quantitative variables. Correlation analysis was employed to determine the strength and significance of the association between CPB duration and renal markers, with p < 0.05 considered statistically significant.

Results: The mean CPB duration was 102.00 ± 33.85 minutes. The mean postoperative creatinine level was 1.1661 ± 0.56801 mg/dl, and the mean urea level was 32.63 ± 10.73 mg/dl. A significant positive correlation was found between CPB duration and both creatinine (r = 0.287, p = 0.003) and urea (r = 0.330, p = 0.001). The mean urine output was 2142.66 ± 392.04 ml, showing a weak negative and non-significant correlation with CPB duration (r = −0.016, p = 0.867).

Conclusion: Longer CPB duration was associated with higher postoperative creatinine and urea levels, reflecting increased renal strain, while urine output showed no significant association. Minimizing CPB duration where clinically feasible may support renal preservation and contribute to improved postoperative outcomes.