Introduction: Acute kidney injury after pediatric liver transplantation (LT) is a serious complication associated with increased morbidity and mortality. There are few data regarding the incidence, risk factors and outcome of KDIGO (Kidney Disease Improving Global Outcomes) based AKI after pediatric LT. The aim of the study was to evaluate children with AKI in the early postoperative period using KDIGO criteria and to compare patients with and without AKI to determine incidence, risk factors and clinical outcomes.
Material and Methods: In this retrospective cohort study, the medical records of all patients aged <16 years undergoing LT from April 2007 to April 2017 was reviewed. AKI was defined according to KDIGO criteria based on serum creatinine and urine output. Recorded data included demographic features and perioperative variables.
Results and Discussion: A total of 117 pediatric liver transplant recipients were analyzed. The mean age of transplantation was 6.1 ± 5.4 years and 69 (59%) were male. Postoperative AKI was seen in 39 (35.8%) children of which 21 (19.3%) had AKI stage 1, 12 (11%) stage 2, 6 (5.5%) stage 3. When compared with children who did not have AKI, preoperative aPTT values (38.9 ± 9.4 seconds vs 45.7 ± 19.3 seconds, p=0.02), intraoperative lactate levels at the end of surgery (5.2 ± 3.3 mmol/L vs 6.9 ± 4.0 mmol/L, p=0.004) andneed for open abdomen (2.9% vs 15.4%, p=0.01) were significantly higher in those children who had AKI. The mean calculated Model for End-Stage Liver Disease and Pediatric End-Stage Liver Disease Scores, intraoperative blood and fluids administered during the intraoperative period were similar in both groups. Logistic regression analysis revealed that preoperative high aPTT levels (odds ratio (OR), 1.043; 95% confidence interval (CI), 1.006-1.082; p=.02), intraoperative end of surgery lactate levels (OR, 1.151; 95%CI, 1.021-1.297; p=.02) and need for open abdomen (OR, 0.162; 95%CI, 0.031-0.845; p=.03) were independent risk factors for AKI. Renal replacement therapy was initiated in 12.8% of children with AKI. Length of ICU stay was significantly longer in children who developed AKI (7.1 ± 8.5 days vs 4.4 ± 5.4 days, p=0.04). Duration of mechanical ventilation and length of hospital stay were similar between the groups. In-hospital mortality was significantly higher in children with AKI (12.8% vs 1.4%, p=.01).
Conclusion: Our results suggest that based on KDIGO criteria early postoperative AKI occur in 35.8% of pediatric liver transplant recipients with an increased risk of mortality. Preoperative high aPTT levels, intraoperative high end of surgery lactate levels and need for open abdomen are associated with AKI after pediatric LT.