Atracurium Versus Cisatracurium Infusion in Prolonged Ophthalmic Surgeries

Atracurium, an isoquinoline muscle relaxant is broken down spontaneously in the blood stream by Hofmann elim-ination however it causes histamine release and causes homodynamic instability. To overcome this problem cisatra-curium was introduced clinically which is a purified form of one of the 10 stereoisomer of atracurium, approximately three times more potent than atracuritum and without histamine release and cardiovascular side-effects in doses as high as eight times the ED95 i.e. 0.4mg/kg.This study compared atracurium versus cisatracurium infusion started after the patient recovers (T1 5-25%) from the bolus dose used for intubation in prolonged ophthalmic surgeries The IOP is measured by Tonometer.The study was conducted on ninety ASA I or II patients over 65 years old which is the common age for patients undergoing prolonged surgeries like vitrectomy and retinal detachment operations that last more than two hours duration, cisatracurium proved to have a slower onset and a longer duration of action than atracurium with nearly on haemody-namic effects while atracurium caused more histamine release than cisatracurium. Recovery from cisatracurium was complete and did not show any recurarization which indicates no cumulative effects for the drug when given by infusion. Once the infusion was closed, full recovery by the aid of neostigmine. Both atracurium and cisatracurium lowered the IOP as all other non depolarizing muscle relaxants.Conclusion: Cisatracurium is safe with no histamine release. It s pharmacokinetics are not changed in elderly whether used as bolus or infusion. It lowers the IOP with no effect on the CVS.