[Effect of atracurium on pancuronium-induced neuromuscular block recovery.].

BACKGROUND AND OBJECTIVES Additional neuromuscular blocker doses are in general needed during wall closing after abdominal surgeries. This study aimed at determining during partial pancuronium-induced neuromuscular block recovery, the effect of additional atracurium dose on spontaneous neuromuscular block recovery. METHODS Participated in this study 30 patients divided in two groups: pancuronium group (n = 14) and atracurium group (n = 16). Neuromuscular function was continuously monitored by accelerometry of abductor pollicis muscle using TOF to supramaximally stimulate ulnar nerve. Anesthesia was induced with propofol, fentanyl and 0.08 mg.kg-1 pancuronium, and was maintained with 60% N2O in oxygen and 0.5% isoflurane expired concentration. When T1 returned to 25% of control, 0.025 mg.kg-1 pancuronium or 0.20 mg.kg-1 atracurium were administered to pancuronium or atracurium group, respectively. Time for spontaneous T1 recovery = 10%, 25%, 75% of recovery index (RI 25-75%) and time to T4/T1 equal 0.8 after complementary dose, were recorded. RESULTS There were no differences between groups on T1 spontaneous recovery to 10% (45.00 +/- 15.50 vs. 49.69 +/- 9.41), 25% (61.64 +/- 18.58 vs. 64.25 +/- 12.51) and 75% (94.00 +/- 28.52 vs. 84.69 +/- 16.50). Recovery index (RI 25-75%) and time to T4/T1= 0.8 were shorter in the atracurium group. CONCLUSIONS In this study, atracurium complementation has made no difference in initial spontaneous recovery of pancuronium-induced neuromuscular block, but has decreased total recovery time in 20%.