Arm-to-arm variation when evaluating neuromuscular block: an analysis of the precision and the bias and agreement between arms when using mechanomyography or acceleromyography.

Background: Studies comparing acceleromyography and mechanomyography indicate that the two methods cannot be used interchangeably. However, it is uncertain to what extent differences in precision between the methods and the naturally occurring arm-to-arm variation have influenced the results of these studies. Accordingly, the purpose of this study was to examine the precision and the arm-to-arm variation, when the same method is used on both of the arms.

Should dosing of rocuronium in obese patients be based on ideal or corrected body weight?

Background: Pharmacokinetic studies in obese patients suggest that dosing of rocuronium should be based on ideal body weight (IBW). This may, however, result in a prolonged onset time or compromised conditions for tracheal intubation. In this study, we compared onset time, conditions for tracheal intubation, and duration of action in obese patients when the intubation dose of rocuronium was based on three different weight corrections.

Is the performance of acceleromyography improved with preload and normalization? A comparison with mechanomyography.

Background: Many studies have indicated that acceleromyography and mechanomyography cannot be used interchangeably. To improve the agreement between the two methods, it has been suggested to use a preload and to refer all train-of-four (TOF) ratios to the control TOF (normalization) when using acceleromyography. The first purpose of this study was to test whether a preload applied to acceleromyography would increase the precision and the agreement with mechanomyography.

Acceleromyography and mechanomyography for establishing potency of neuromuscular blocking agents: a randomized-controlled trial.

Background: Acceleromyography (AMG) is increasingly being used in neuromuscular research, including in studies establishing the potency of neuromuscular blocking and reversal agents. However, AMG is insufficiently validated for use interchangeably with the gold standard, mechanomyography (MMG) for this purpose. The aim of this study was to compare AMG and MMG for establishing dose-response relationship and potency, using rocuronium as an example.

The undesirable effects of neuromuscular blocking drugs.

Neuromuscular blocking drugs are designed to bind to the nicotinic receptor at the neuromuscular junction. However, they also interact with other acetylcholine receptors in the body. Binding to these receptors causes adverse effects that vary with the specificity for the cholinergic receptor in question.

Acceleromyography for use in scientific and clinical practice: a systematic review of the evidence.

This systematic review describes the evidence on the use of acceleromyography for perioperative neuromuscular monitoring in clinical practice and research. The review documents that although acceleromyography is widely used in research, it cannot be used interchangeably with mechanomyography and electromyography for construction of dose-response curves or for recording different pharmacodynamic variables after injection of a neuromuscular blocking agent. Some studies indicate that it may be beneficial to use a preload to increase the precision of acceleromyography, and to "normalize" the train-of-four ratio to decrease the bias in relation to mechanomyography and electromyography.

Two novel mutations in the BCHE gene in patients with prolonged duration of action of mivacurium or succinylcholine during anaesthesia.

Background: Butyrylcholinesterase (BChE) hydrolyses the neuromuscular blocking agents, succinylcholine and mivacurium used during general anaesthesia. Hereditary low BChE activity may result in an extensively prolonged duration of action of these drugs, especially in patients who are homozygous for the atypical or silent variants. We present three novel mutations in the butyrylcholinesterase gene (BCHE) identified in three families in which a member had experienced severely prolonged duration of action of succinylcholine.

Prolonged residual paralysis after a single intubating dose of rocuronium.

It is often argued that neuromuscular monitoring is unnecessary when only one dose of an intermediate-acting neuromuscular blocking agent is given. This case report documents that it may take more than 3.5 h before it is possible to antagonize a block caused by a normal dose of rocuronium (0.

Good clinical research practice in pharmacodynamic studies of neuromuscular blocking agents II: the Stockholm revision.

The set of guidelines for good clinical research practice (GCRP) in pharmacodynamic studies of neuromuscular blocking agents, which was developed following an international consensus conference in Copenhagen, has been revised and updated following the second consensus conference in Stockholm in 2005. It is hoped that these guidelines will continue to help researchers in the field and assist the pharmaceutical industry and equipment manufacturers in enhancing the standards of the studies they sponsor.

Neuromuscular monitoring.

This review summarizes recent reports on the techniques and the use of methods for monitoring neuromuscular function during anaesthesia. The latest news on the use of acceleromyography in the face and hand, on laryngeal and diaphragmal surface electromyography, on acoustic myography, on evaluation of intense neuromuscular block, and on postoperative residual curarization is presented and discussed. It is concluded that available evidence suggests that more attention should be paid by the anaesthetist to the problems of residual curarization and hence to proper monitoring of neuromuscular function using objective methods.

Reversal of rocuronium-induced neuromuscular block by the selective relaxant binding agent sugammadex: a dose-finding and safety study.

Background: Sugammadex (Org 25969) forms a complex with steroidal neuromuscular blocking agents, thereby reversing neuromuscular block. This study investigated the dose-response relation, safety, and pharmacokinetics of sugammadex to reverse rocuronium-induced block.

Methods: Twenty-seven male surgical patients aged 18-64 yr were randomly assigned to receive placebo or sugammadex (0.

[Does evidence lead to a change in clinical practice? Danish anaesthetists' and nurse anesthetists' clinical practice and knowledge of postoperative residual curarization].

Background: Recent studies have shown a high incidence of postoperative residual curarization (PORC). The reason for this is unclear. The purpose of this study was to evaluate whether the methods used by Danish anaesthetists to exclude PORC are evidence-based and, if they are not, to determine the reasons why.

Pharmacokinetics and pharmacodynamics of mivacurium in patients phenotypically homozygous for the atypical plasma cholinesterase variant: effect of injection of human cholinesterase.

Background: In patients homozygous for atypical plasma cholinesterase, mivacurium causes a long-lasting neuromuscular block, but injection of human cholinesterase has been proven effective in antagonizing the block. The purpose of this study was to evaluate the pharmacodynamics and pharmacokinetics of mivacurium in such patients, as well as the effect of cholinesterase injected early or late after mivacurium.

Methods: Eleven patients phenotypically homozygous for the atypical variant received 0.

Response to mivacurium in patients carrying the k variant in the butyrylcholinesterase gene.

Background: Mivacurium is hydrolyzed by the butyrylcholinesterase enzyme, and patients with hereditary changes of the enzyme often have prolonged duration of action of mivacurium. In this study, the authors investigated the significance of the most commonly occurring variant, the Kalow (K) variant, established using DNA analysis, for the response to mivacurium.

Methods: A total of 58 patients carrying either the wild-type butyrylcholinesterase or different combinations of the atypical (A) variant and the K variant were included.

Remifentanil vs. alfentanil infusion in non-paralysed patients: a randomized, double-blind study.

Background And Objective: Remifentanil has a short duration of action and constant elimination, which allow administration of high doses, without prolonging recovery. Remifentanil has been compared to alfentanil, as part of a total intravenous anaesthetic technique, where remifentanil provided better anaesthetic conditions than alfentanil, without adverse effect on recovery. However, these results were obtained during anaesthesia involving neuromuscular blockade, which may mask both signs of insufficient anaesthesia and side-effects such as muscle rigidity.

Scandinavian research in anaesthesiology 1981-2000: visibility and impact in EU and world context.

Background: We wished to assess the development in number and impact of publications in anaesthesiology and intensive care medicine from 1981 to 2000 in the four Scandinavian countries: Sweden, Norway, Finland, and Denmark. For comparison, we also analyzed data from the UK and the Netherlands.

Methods: Publication and citation data from 1981 to 2000 were gathered from National Science Indicators (2001), covering 33 journals indexed in Current Contents.

Pharmacokinetics and pharmacodynamics of mivacurium in patients phenotypically heterozygous for the usual and atypical plasma cholinesterase variants (UA).

Background: Mivacurium is hydrolyzed by plasma cholinesterase (pChe). The purpose of this study was to evaluate the pharmacodynamics and the pharmacokinetics of the three isomers of mivacurium in patients phenotypically heterozygous for the usual and the atypical pChe variant (UA).

Methods: Thirty-two patients were included in a dose-response study, in which the patients received one of four doses of mivacurium.