Surgeon-controlled mivacurium administration during elective caesarean section.
We have compared the dose requirements and recovery characteristics of a continuous mivacurium infusion given by the anaesthetist to maintain 95-100% block at the hand muscles with that of a surgeon-controlled, on-demand dosing technique based on the direct assessment of abdominal muscle tone during elective Caesarean section. Twenty-four full term pregnant patients were included. A rapid-sequence induction using thiopentone 3-5 mg.kg-1 and succinylcholine 1 mg.kg-1 was used. Anaesthesia was maintained with fentanyl, N2O and isoflurane 0.5%. The mechanomyographic response of the adductor pollicis muscle to supramaximal train-of-four (TOF) ulnar nerve stimulation was recorded. Muscle relaxation was achieved initially with mivacurium 0.1 mg.kg-1 followed either by a continuous infusion of mivacurium to maintain 95-100% block at the adductor pollicis muscle (n = 12) or by surgeon-controlled relaxation (SCR) technique using a syringe pump for patient-controlled analgesia to administer on-demand doses of mivacurium 0.05 mg.kg-1 (n = 12). The lockout interval was three minutes and the maximum hourly dose of mivacurium allowed was 0.6 mg.kg-1. The total doses of mivacurium (mean +/- SD) were 23.2 +/- 10.4 and 12.4 +/- 3.5 mg in the infusion and SCR groups, P < 0.01. On-demand, surgeon-controlled doses of mivacurium were injected at a mean of T1 42.3 +/- 36%. At the end of surgery, T1 and TOF ratio were respectively 16.7 +/- 13%, 5 +/- 10% and 48 +/- 37%, 30 +/- 24% in the infusion and SCR groups.(ABSTRACT TRUNCATED AT 250 WORDS)
Abdulatif
M
M
Department of Anaesthesia, Faculty of Medicine, Cairo University, Egypt.
Taylouni
E
E
D000009:Abdominal Muscles / Q000187:drug effects; D000328:Adult; D000762:Anesthesia Recovery Period; D000771:Anesthesia, Intravenous; D000773:Anesthesia, Obstetrical; D000776:Anesthesiology; D002585:Cesarean Section; D017558:Elective Surgical Procedures; D004558:Electric Stimulation; D005260:Female; D013502:General Surgery; D006225:Hand; D006801:Humans; D007260:Infusion Pumps; D007546:Isoquinolines / Q000008:administration & dosage*; D000077590:Mivacurium; D009119:Muscle Contraction / Q000187:drug effects; D018482:Muscle, Skeletal / Q000187:drug effects; D009469:Neuromuscular Junction / Q000187:drug effects; D003473:Neuromuscular Nondepolarizing Agents / Q000008:administration & dosage*; D011247:Pregnancy; D014459:Ulnar Nerve / Q000502:physiology
D007546:Isoquinolines; D003473:Neuromuscular Nondepolarizing Agents; D000077590:Mivacurium