The effect of defasciculating doses of pancuronium and atracurium on succinylcholine neuromuscular blockade.

Background: A defasciculating dose of non-depolarizing muscle relaxant administered prior succinylcholine decrease its side effects including fasciculations and postoperative myalgias; however it is believed that the dosage of succinylcholine should be increased when such a pre-treatment is used.

Objectives: We hypothesized that a defasciculating dose of pancuronium as a pre-treatment could prolong its duration of effect.

Patients And Methods: Forty patients scheduled for elective orthopaedic surgery were consecutively assigned into 5 groups, a first group without pre-treatment (succinylcholine 1 mg/kg) and 4 subsequent groups of pretreatment with atracurium 0.