Accumulation of Postoperative Unexpected Events Assessed by the Comprehensive Complication Index Are Prognostic Outcome Parameters After Kasai Procedure

Introduction Kasai procedure in children with biliary atresia (BA) is associated with several complications in the short-term. The Comprehensive Complication Index (CCI) is a validated metric in adult surgery for the analysis of complication and morbidity in surgical patients. We aimed to analyze the CCI for the first time in BA infants and to corelate its association with the outcome. Material and Methods Retrospective review of medical records of infants with type III BA undergoing Kasai procedure between January 2011 and December 2021 at our institution. All unexpected events were ranked according to the Clavien-Dindo classification and the CCI per patient was subsequently calculated. Clavien-Dindo grades, individual events, the CCI and the total event number per patient were correlated with the one- and two-year outcome post Kasai. Results 131 events were identified in 101 patients (range 0 – 11 per patient). Forty-four Grade I (33.6%), 67 Grade II (51.1%), 18 Grade III (13.7%) and two sentinel events [> Grade IV] (1.5%) were documented according to Clavien-Dindo, including one death in a cardiac-associated BA patient. None of the complications correlated significantly with a poor outcome. Sixty-three (62.4%) CCI were calculated (range 0 – 100). The mean CCI during the in-patient treatment post Kasai, was significantly higher in patients with a poorer outcome compared to patients with native liver survival at one- and two-year follow-up (22.7 21.7 vs 13.2 18.1; p=0.02). Conclusion Not the severity of complications, but the accumulation of numerous events related to Kasai procedure are associated with a poorer outcome. Therefore, the CCI is an excellent instrument for the postoperative morbidity assessment of BA patients.