Risk Factors and Consequences of Acute Kidney Injury After Noncardiac Surgery in Children

Postoperative acute kidney injury (AKI) is a serious complication that is associated with prolonged hospital stay, high risk of short-term postsurgical mortality, need for dialysis, and possible progression to chronic kidney disease. To date, very little data exist on the risk of postoperative AKI among children undergoing noncardiac surgical procedures. We used data from a large multicenter cohort to determine the factors associated with AKI among children who underwent inpatient noncardiac surgical procedures and its impact on the postoperative course.

We utilized the National Surgical Quality Improvement Program Pediatric participant user files to identify a cohort of children who underwent inpatient surgery between 2012 and 2018 (n = 257,439). We randomly divided the study population into a derivation cohort of 193,082 (75%) and a validation cohort of 64,357 (25%), and constructed a multivariable logistic regression model to identify independent risk factors for AKI. We defined AKI as the occurrence of either acute renal failure or progressive renal insufficiency within the 30 days after surgery.

The overall rate of postoperative AKI was 0.10% (95% confidence interval [CI], 0.09-0.11). In a multivariable model, operating times longer than 140 minutes, preexisting hematologic disorder, and preoperative sepsis were the strongest independent predictors of AKI. Other independent risk factors for AKI were American Society of Anesthesiologists (ASA) physical status ≥III, preoperative inotropic support, gastrointestinal disease, ventilator dependency, and corticosteroid use. The 30-day mortality rate was 10.1% in children who developed AKI and 0.19% in their counterparts without AKI ( P < .001). Children who developed AKI were more likely to require an extended hospital stay (≥75th percentile of the study cohort) relative to their peers without AKI (77.4% vs 21.0%; P < .001).

Independent preoperative risk factors for AKI in children undergoing inpatient noncardiac surgery were hematologic disorder, preoperative sepsis, ASA physical status ≥III, inotropic support, gastrointestinal disease, ventilator dependency, and steroid use. Children with AKI were 10 times more likely to die and nearly 3 times more likely to require an extended hospital stay, relative to their peers without AKI.