Priming with anticholinesterases — the effect of different priming doses of edrophonium

Abstract

The effect of different priming doses of edrophonium were studied in 77 patients divided into seven groups (n = 11 in each). Edrophonium ] .0 mg.kg -I was administered either dn a single bolus dose (Group I: controls) or in on initial dose of O.05, O. 1, O-15, 0,2, 0.25 We reported that divided administration of neostigmine or edrophonium hastens the recovery of atracurium-induccd neuromuscular blockade as compared to a single bolus administration of the antagonist, t,2 We also demonstrated that a one minute priming interval and the adminislration of edroph0nium in divided doses resulted in the fastest recovery rate following antagonism of atracurium induced neuromuscular blockade as compared to different combinations of neostigmine and edrophonium at different intervals. 3This study was undertaken to investigate the reversal characteristics following different priming doses of edropbonium. MethodsAfter institutional approval, 77 ASA physical status I or I1 adult patients undergoing minor elective procedures were studied. All patients were free of neuromuscular~ renal or hepatic disease and were not taking any drugs known to interfere with neuromuscular function. Informed consent was obtained. All patients were premedicated with diazepam 0.15 mg'kg-I PO 90 minutes preoperatively, An intravenous infusion of lactated Ringer's solution in five per cent dextrose was established prior to induction. The ECG and nasopharyngeal temperature were monitored continuously by a Medishield ~ MI monitor. Blood pressure was measured every five minutes by an electronic oscillotonometer (Dinamap| In all patients, anaesthesia was induced with fentanyl 2.0 ~g.kg -t thiopentone 5.0 mg.kg -~ and was maintained with 70 per cent nitrous oxide in oxygen and halothane (0.5-1 per cent). Ventilation was adjusted to maintain normocapnia and end-tidal COz was monitored by a Datex infra-red CO2 analyzer.The ulnar nerve was stimulated at the wrist with square wave supramaximal stimuli of 0.2 ms duration, delivered in a train-of-four (TOF) sequence at 2 Hz every ten seconds, using a Myotest e peripheral nerve stinlulator (Biometer). The resultant contraction of adductor pollicis was recorded using a force displacement transducer and

Edrophonium priming for antagonism of atracurium neuro-muscular blockade

“…A priming dose of 0.2 mg.kg-' was reported to be the most effective in the range of 0.05-0.3 mg.kg-t. 4 Finally, the three-minute priming interval, when applied to 0.2 mg. kg -t followed by 0.8 mg. kg -~, was associated with the shortest reversal time among different combinations tested in another study. 3 The only apparent difference between this study and those of Naguib et al [2][3][4][5] is the inhalational agent used; enflurane was used in this study instead of halothane. Our choice was dictated by the popularity of the agent in clinical practice and in an attempt to "stress the system."…”

Edrophonium priming alters the course of neuromuscular recovery from a pipecuronium neuromuscular blockade

“…This acceleration of recovery was noted during antagonism of atracurium blockade as well. [4][5][6][7] found that divided administration anticholinesterases did not result in acceleration of recovery of atracurium blockade.t~'~2 Others administered repeated doses of neostigmine (70 p,g. kg-' each) in the presence of profound vecuronium neuromuscular blockade and concluded that repeated administration of neostigmine provided no evidence of hastened recovery, t3…”

“…3 We have demonstrated previously that a marked acceleration of recovery of atracurium neuromuscular blockade could be achieved with the administration of edrophonium in divided doses. [4][5][6][7][8] This study was designed to determine whether divided administration of different doses of edrophonium could alter the course of neuromuscular recovery from a pipecuronium neuromuscular blockade.…”