In a 2 months old infant undergoing surgery for biliary atresia, you would avoid one of the following anaesthetic –

The child with biliary atresia will have hepatic dysfunction. Sevoflurane, thiopentone and propofol are safe in liver disease. Halothane is not contraindicated in pre-existing liver :- "There is no compelling evidence associated with worsening of pre-existing liver disease". ─Morgan "Pre-existing liver disease unrelated to halothane is not a contraindication to the use of halothane". —Lee 13th/e 143 Though not a contraindication, halothane should be avoided in liver disease - "Potentialy hepatotoxic drug should be avoided".  —Lee 55