[Analysis of factors influencing prognosis in patients with acute kidney injury receiving continuous renal replacement therapy after cardiac surgery].

Objective

To analyze the factors influencing prognosis in patients with acute kidney injury (AKI) receiving continuous renal replacement therapy (CRRT) after cardiac surgery.

Methods

The data of patients who developed postoperative AKI and received CRRT after cardiac surgery at Fuwai Huazhong Cardiovascular Disease Hospital from January 1, 2018 to December 31, 2020, were retrospectively analyzed. All patients were followed up for 90 days after surgery. The primary endpoint was a composite of dialysis dependence or death at 90 days postoperatively. Patients were divided into a successful renal replacement therapy (RRT) group and a failed RRT group according to whether the endpoint occurred. The clinical data were compared between the two groups. A logistic regression model was used to identify independent risk factors for 90-day RRT failure in AKI patients treated with CRRT after surgery, and the area under the receiver operating characteristic (ROC) curve was calculated to evaluate the predictive performance of the model.

Results

A total of 113 patients aged (57.7±12.3) years were enrolled, including 55 males and 58 females. There were 56 patients in the successful RRT group and 57 in the failed RRT group, respectively. Compared with the successful RRT group, patients in the failed RRT group had a higher preoperative prevalence of diabetes mellitus [29.8% (17/57) vs 3.6% (2/56)], lower intraoperative transfused red blood cell volume [(474±188) ml vs (559±195) ml] and platelet units [(1.2±0.6) U vs (1.5±0.7) U], higher serum creatinine at discharge [(230±167) μmol/L vs (129±80) μmol/L], and a larger proportion of dialysis dependence at discharge [80.7% (46/57) vs 39.3% (22/56)] (all P<0.05). Multivariate logistic regression analysis showed that male sex (OR=2.930, 95%CI: 1.086-7.904, P=0.034), preoperative diabetes mellitus (OR=12.033, 95%CI: 2.136-67.780, P=0.005), serum creatinine at discharge (OR=1.006, 95%CI: 1.002-1.010, P=0.005), and dialysis dependence at discharge (OR=5.147, 95%CI: 1.762-15.036, P=0.003) were independent risk factors for 90-day RRT failure in AKI patients receiving CRRT after cardiac surgery. The risk prediction model constructed with male sex, preoperative diabetes mellitus, serum creatinine at discharge and dialysis dependence at discharge yielded an area under the ROC curve of 0.850 (95%CI: 0.782-0.918, P<0.001).

Conclusion

Male sex, preoperative diabetes mellitus, and elevated serum creatinine and dialysis dependence at discharge are risk factors for 90-day RRT failure in AKI patients treated with CRRT after cardiac surgery.