Mivacurium Metoclopramide

Skinner HJ, Girling KJ, Whitehurst A, NathansonMH. Influence of metoclopramide on plasma cholinesterase and duration of action of mivacurium. BrJ Anaesth (1999) 82, 542-5. 

El Ayass N, Hendrickx P. Decreased mivacurium infusion rate and delayed neuromuscular recovery after metoclopramide a randomized double blind placebo-controlled study. EurJAn-aesthesiol 2005) 22, 197-201. 

Motamed C, Kirov K, Combes X, Dhonneur G, Duvaldestin P. Effect of metoclopramide on mivacurium-induced neuromuscular h oz i.ActaAnaesthesiolScandO.002) 46, 214-16. 

The neuromuscular blocking effects of suxamethonium (succinylcholine) and mivacurium can be increased and prolonged in patients taking metoclopramide. 

A randomised, placebo-controlled, double-blind study in 30 patients found that 150 micrograms/kg of intravenous metoclopramide given prior to anaesthetic induction about 10 minutes before mivacurium 150 micrograms/kg prolonged the duration of action of mivacurium by about 30%.Another report found that infusion rates of mivacurium were reduced by up to about 80% in patients given metoclopramide 10 or 20 mg intravenously, 5 minutes before induction, and metoclopramide delayed complete recovery from neuromuscular block after mivacurium by 36% (10 mg dose) and 50% (20 mg dose). Delays in recovery from mivacurium block of 78% after metoclopramide 20 mg were found in another study. ... 

Metoclopramide is postulated to reduce the activity of plasma cholinesterase, which is responsible for the metabolism of suxamethonium and mivacurium. One in vitro study found that a metoclopramide level of 800 nanograms/mL inhibited plasma cholinesterase aetivity by 50%. However, a 10-mg dose of metoclopramide in adult patients weighing 50 to 70 kg produces peak plasma levels five times less than this (140 nanograms/mL). Further, in an in vivo study, metoclopramide had only minimal inhibitory effects on plasma cholinesterase, and there was no difference in plasma cholinesterase levels in patients who had received metoclopramide and those who had not. ... 

The interaction between metoclopramide and suxamethonium is an established but not extensively documented interaction of only moderate or minor clinical importance. However anaesthetists should be aware that some enhancement of blockade can occur. The interaction between metoelopra-mide and mivacurium has only more recently been demonstrated. Metoclopramide appears to allow a reduction in the infusion rate of mivaeurium and it causes a significant delay in recovery from neuromuscular block. Care is recommended during combined use. The authors of the suxamethonium reports also point out that plasma cholinesterase activity is reduced in pregnancy and so suxamethonium sensitivity is more likely in obstetric patients. Ester-type local anaesthetics also depend on plasma... 

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