The ideal muscle relaxant used for a neonate undergoing poo-enterostomy for biliary atresia is:

A i.e. Atracurium In this case a muscle relaxant is required whose metabolism has nothing to do with liver (preferabely) & it should not be excreted through bile. The straight forward answer is atracurium/cisatracurium as these are inactivated in plasma by spontaneous non enzymatic degradation (Hoffman elimination) independant of hepatic or renal function and biliary or urinary exceretion.