After suxamethonium 50mg, apnea persists for one hour --
treatment with cholnesterase is indicated
Probably an atypical cholinesterase is present
Treatment with stored blood is indicated
Apnea may be due to low serum potassium concentration
Suxamethonium is a depolarising muscle relaxant used to rapidly gain optimal intubating conditions. It is normally metabolised within 5 minutes by plasma cholinesterase. Some patients lack this enzyme or have an altered enzyme that does not metabolise the suxamethonium as rapidly. These patients may remain paralysed for a prolonged period after a standard dose of suxamethonium and rely on renal elimination. This condition is often referred to as suxamethonium apnea
Muscle relaxants