Biochemical changes following succinylcholine administration after pretreatment with rocuronium at different intervals

Objective: to evaluate the biochemical changes associated with succinylcholine administration after pretreatment with rocuronium at different time intervals. method: the prospective, randomised, single-blinded study was conducted at the combined military hospital, rawalpindi, from january to may 2010. ninety male, aged 18-60 years, american society of anaesthesiology i or ii patients undergoing elective inguinal herniotomy or external haemorrhoidectomy were included. the patients were randomly divided into three equal groups. group a received a normal saline 5ml as placebo 1 minute before succinylcholine; group b received rocuronium 0.06 mg/kg 1 intravenously minute before succinylcholine, while group c received intravenous injection of rocuronium 0.06 mg/kg 5 minute before succinylcholine. venous blood samples for creatinine phosphokinase, lactate dehydrogenase and myoglobin plasma concentrations were obtained at 0, 30 minutes, 6 hours and 24 hours after succinylcholine administration. results: mean serum creatinine phosphokinase and myoglobin concentrations were significantly decreased in groups b and c compared to group a at 30 minutes and 24 hours (p<0.05). however, no significant difference in the enzyme levels at any time interval was observed among the rocuronium groups. there was a significant rise in lactate dehydrogenase concentrations at 6 hours and 24 hours in group a compared to groups b and c (p<0.05). conclusion: pretreatment with rocuronium effectively reduces the biochemical changes associated with succinylcholine-induced muscle fasciculations. however, whether it is given 1 minute or 5 minutes before succinylcholine does not make much difference.