Risk factors and outcomes associated with acute kidney injury following extracardiac total cavopulmonary connection: a retrospective observational study

BACKGROUND: Total cavopulmonary connection (TCPC) is an important operation for the treatment of complex congenital heart disease. Epidemiology and outcomes for pediatric patients with acute kidney injury (AKI) following extracardiac TCPC have not been well documented. This study investigates the prevalence, risk factors, and outcomes of AKI in children after extracardiac TCPC surgery. METHODS: We retrospectively evaluated patients (age at surgery <18 years) who underwent extracardiac TCPC surgery between January 2008 and January 2020 in the Pediatric Cardiac Surgical Center of Fuwai Hospital, Beijing, China. AKI was defined according to the pediatric-modified risk, injury, failure, loss of function, and end-stage renal disease criteria. RESULTS: A total of 377 pediatric patients were included in this study; 123 patients (32.6%) had some degree of AKI. Among the patients with AKI, 101 (82.1%) were diagnosed with AKI-risk (AKI-R), while 22 (17.9%) were diagnosed with acute kidney injury/failure (AKI/F) (16 with AKI, and 6 with AKF). Preoperative estimated creatinine clearance (OR: 1.039, 95% CI: 1.024–1.055, P<0.001), neutrophil-to-lymphocyte ratio (OR: 1.208, 95% CI: 1.128–1.294, P<0.001), and renal perfusion pressure (OR: 0.962, 95% CI: 0.938–0.986, P=0.002) on postoperative day (POD) 0 were significantly associated with AKI after TCPC. Having previously undergone a bidirectional Glenn was significantly associated with the severity of postoperative AKI (OR: 0.253, 95% CI: 0.088–0.731, P=0.011). Furthermore, AKI was associated with prolonged mechanical ventilation time, prolonged intensive care unit stay, and composite adverse outcome. Compared with non-AKI patients, the 10-year survival rate of patients with severe AKI was significantly lower (95.5% vs. 65.9%, P=0.009). CONCLUSIONS: Although the incidence of AKI was high in patients undergoing TCPC surgery, most cases were AKI-R. Severe AKI was significantly associated with early adverse outcomes and poor long-term survival.