RESUMO
Magnesium inhibits the release of acetylcholine from the motor nerve terminals and thus potentiates the action of the non- depolarizing neuromuscular blocking drugs. The effect of pretreatment with magnesium sulfate on the neuromuscular block after atracurium administration was studied. Forty adult patients were allocated randomly into two groups. Control group [n=20] received atracurium only, while the MgSO4 group [n=20] received atracurium after pretreatment with MgSO4 [40 mg kg-1]. In all patients midazolam was given as premedication and anesthesia was induced with fentanyl and thiopentone and tracheal intubation was performed with atracurium 0.5 mg kg-1. The neuromuscular transmission was monitored using mechanomyography and TOF stimulation. For each patient the onset time, the clinical duration, the recovery index were determined. The intubation time and the intubation conditions were also described. The results are given and discussed