Perioperative management of pediatric patients with inborn errors of metabolism during liver transplantation

Abstract

Inborn errors of metabolism (IEM) are rare disorders, most are liver-based with liver transplantation (LT) emerging as an effective cure in the pediatric population. LT has been shown to offer a cure or deter disease progression and provide symptomatic improvement in patients with IEM. Each metabolic disorder is unique, with the missing enzyme or transporter protein causing substrate deficiency or toxic byproduct production. Knowledge about the distribution of deficient enzymes, the percentage of enzymes replaced by LT, and the extent of extrahepatic involvement helps anticipate and manage complications in the perioperative period. Most patients have multisystem involvement and can be on complex dietary regimens. Metabolic decompensation can be triggered due to the stress response to surgery, fasting and other unanticipated complications perioperatively. Thus, a multidisciplinary team’s input including those from metabolic specialists is essential to develop disease and patient-specific strategies for the perioperative management of these patients during LT. In this review, we outline the classification of IEM, indications for LT along with potential benefits, basic metabolic defects and their implications, details of extrahepatic involvement and perioperative management strategies for LT in children with some of the commonly presenting IEM, to assist anesthesiologists handling this cohort of patients.

Keywords: Inborn errors of metabolism; Anaesthesia for paediatric liver transplantation; Metabolic crisis; Hyperammonemia in paediatric liver transplantation; Perioperative care in metabolic liver diseases

Core Tip: Most metabolic disorders are liver-based, and liver transplantation (LT) has emerged as an effective cure for a variety of inherited metabolic disorders in the pediatric population. LT has been shown to offer a cure, deter disease progression and provide symptomatic improvement in patients with inherited metabolic disorders. Perioperative management of these children presenting for LT with inborn errors of metabolism requires disease specific and patient specific strategies in all aspects right from preoperative assessment, intraoperative and postoperative management compared to those presenting with other indications. Knowledge about the distribution of deficient enzymes, the percentage of enzymes replaced by LT, and the extent of extrahepatic involvement helps anticipate and manage complications in the perioperative period.