Mivacurium-induced Neuromuscular Block Research Articles

Mivacurium-induced neuromuscular block in adult patients suffering from Charcot-Marie-Tooth disease

The response to non-depolarizing neuromuscular blocking drugs is variable in patients with Charcot-Marie-Tooth (CMT) disease. We speculated that CMT involvement of the monitored muscle may be partially responsible for this inconsistency. We therefore investigated the response to a standard dose of mivacurium simultaneously assessed at adductor pollicis (AP) and orbicularis oculi (OO) muscles in five patients with CMT. Over a period of one year, five adult patients with CMT scheduled for orthopedic surgery were studied. The right arm and the right supercilliary arch were prepared for acceleromyographic (AMG) neuromuscular monitoring. The AMG probes were attached at the distal interphalangeal joint of the right thumb and on the right upper eyelid to record the response of the AP and OO, respectively. The ulnar nerve and upper part of the facial nerve were stimulated supramaximally with repeated train-of-four stimuli (2 Hz, 0.2 msec) every 15 sec via applied surface electrodes. Following monitor calibration and induction of general anesthesia, mivacurium 0.2 mg x kg(- 1) iv was given, and the time course of relaxation and recovery were assessed. Times to spontaneous recovery of T1 to 25% were 15 +/- 3 vs 12 +/- 4 min in the AP and OO muscle groups respectively, whereas times to 90% recovery were 23 +/- 5 vs 29 +/- 10 min, respectively. The onset and recovery characteristics associated with mivacurium-induced neuromuscular block were similar at the AP and OO muscle groups. A near normal response to mivacurium was observed in this small series of patients with CMT disease.

Onset and Duration of Mivacurium-Induced Neuromuscular Block in Patients With Duchenne Muscular Dystrophy

Survey of Anesthesiology: August 2006 - Volume 50 - Issue 4 - p 194-195 doi: 10.1097/01.sa.0000234696.92118.4a

Onset and duration of mivacurium-induced neuromuscular block in patients with Duchenne muscular dystrophy

To determine the response to mivacurium, we prospectively studied onset time and complete spontaneous recovery from mivacurium-induced neuromuscular block in patients with Duchenne muscular dystrophy (DMD). Twelve boys with DMD, age 5-14 yr, seven of them wheelchair-bound, ASA II-III, and 12 age- and sex-matched controls (ASA I) were enrolled in the study. Anaesthesia was induced with fentanyl 2-3 microg kg(-1) and propofol 3-4 mg kg(-1) titrated to effect, and maintained by continuous i.v. infusion of propofol 8-12 mg kg(-1) and remifentanil as required. The lungs were ventilated with oxygen in air. Neuromuscular transmission was assessed by acceleromyography using train-of-four (TOF) stimulation every 15 s. After baseline readings, a single dose of mivacurium 0.2 mg kg(-1) was given. The following variables were recorded: (i) lag time; (ii) onset time; (iii) peak effect; (iv) recovery of first twitch from the TOF response to 10, 25 and 90% (T(10), T(25), T(90)) relative to baseline; (v) recovery index (time between 25 and 75% recovery of first twitch); and (vi) recovery time (time between 25% recovery of first twitch and recovery of TOF ratio to 90%). For comparison between the groups the Mann-Whitney U-test was applied. There were no differences between the groups in lag time, onset time and peak effect. However, all recorded recovery indices were significantly (P<0.05) prolonged in the DMD group. The median (range) for time points T(10), T(25) and T(90) in the DMD and control group was 12.0 (8-16) vs 8.4 (5-15) min, 14.1 (9-20) vs 10.5 (7-17) min and 26.9 (15-40) vs 15.9 (12-23) min, respectively. The recovery index and recovery time were similarly prolonged in the DMD group. These results support the assumption that mivacurium-induced neuromuscular block is prolonged in patients with DMD.

Onset and duration of mivacurium‐induced neuromuscular blockade in children with Charcot–Marie–Tooth disease. A case series with five children

The Charcot-Marie-Tooth (CMT) disorders are a group of hereditary motor and sensory neuropathies characterized clinically by peripheral muscle wasting and weakness. We hypothesized that unknown involvement of the muscle used for monitoring neuromuscular block may account for the conflicting reports about the effect of nondepolarizing neuromuscular agents in these patients. The aim of this study was to compare onset and recovery from mivacurium-induced neuromuscular block on the adductor pollicis and orbicularis oculi muscles. We used mivacurium 0.2 mg.kg(-1) in five children (aged 7-12 years) with CMT type I undergoing propofol-fentanyl-oxygen-air anesthesia for orthopedic surgery. Using acceleromyography, neuromuscular transmission was monitored in parallel in the eye and thumb muscles, and onset and duration times were recorded. Following bolus administration of 0.2 mg.kg(-1) of mivacurium the onset time ranged between 135 and 240 s and 75 and 165 s in the eye and in the thumb, respectively. The recovery time varied between 5.3 and 16 min and 6 and 31.3 min in the eye and in the thumb, respectively. In our small series of patients with CMT the clinical duration of mivacurium-induced neuromuscular block was similar to data known from children without neuromuscular disease.

The Nature of Spontaneous Recovery From Mivacurium-Induced Neuromuscular Block

LIEN, CYNTHIA A.; BELMONT, MATTHEW R.; ABALOS, AMY; HASS, DAVID; SAVARESE, JOHN J. Author Information

The Nature of Spontaneous Recovery from Mivacurium-Induced Neuromuscular Block

The Nature of Spontaneous Recovery from Mivacurium-Induced Neuromuscular Block

Mivacurium compared with succinylcholine in children with liver disease

We have compared mivacurium and succinylcholine in 27 paediatric patients with mild (Child's A) to moderate (Child's B) liver disease undergoing oesophagogastroduodenoscopy (OGD) and injection of oesophageal varices, with 10 healthy children receiving mivacurium for ENT procedures. With mivacurium 0.2 mg kg-1, the severity of liver disease did not correlate with duration of block compared with controls (time from bolus to T1 25%, P = 0.74; T1 25% to T4:T1 > 0.7, P = 0.545). However, initial recovery (time to T1 25%, P = 0.002) and overall recovery (bolus to T4:T1 > 0.7, P = 0.004) from mivacurium-induced neuromuscular block correlated inversely with pre-existing concentrations of plasma cholinesterase. Conditions for tracheal intubation at 2 min with mivacurium were comparable with conditions at 1 min with succinylcholine in the liver patients.

Which monitoring during mivacurium-induced neuromuscular block?

Which monitoring during mivacurium-induced neuromuscular block?

Blood flow and mivacurium-induced neuromuscular block at the orbicularis oculi and adductor pollicis muscles

We have studied the pattern of blood flow and pharmacodynamic profile of mivacurium-induced block at the adductor pollicis and orbicularis oculi muscles. We studied 30 adult patients anaesthetized with fentanyl, thiopentone, nitrous oxide-isoflurane, and mivacurium 0.2 mg kg-1. Neuromuscular transmission was monitored with accelerometry (TOF Guard, Biometer, Denmark). Blood flow was measured at the two muscles with the use of a laser Doppler flowmeter (Laserflo BPM2, Vasamedics, USA). All patients developed 100% neuromuscular block at the adductor pollicis muscle. Mean maximum neuromuscular block at the orbicularis oculi was 96.4 (SD 3.5)% (ns). Onset time, time required for 25% and 75% recovery of the first twitch in the train-of-four (T1), and a train-of-four ratio (T4/T1) of 90% at the orbicularis oculi were respectively, mean 130.4 (SD 28.5) s, 9.1 (3.2) min, 16.2 (3.9) min and 20.2 (4.3) min and were significantly shorter than the corresponding values at the adductor pollicis: 202.7 (37.2) s, 12.9 (3.9) min, 21.1 (5.1) min and 30.8 (7.4) min. For a given T1, there was significantly less train-of-four fade (T4/T1) at the orbicularis oculi than at the adductor pollicis muscle during recovery. Blood flow was comparable at the two muscles before induction of anaesthesia. Thiopentone significantly increased thenar muscle blood flow from 2.9 (1.5) to 12.3 (6.8) ml 100 g-1 min-1, with a further increase to 22.7 (8.0) ml 100 g-1 min-1 after isoflurane (P < 0.001). Blood flow at the orbicularis oculi was not altered by thiopentone or isoflurane and was consistently lower than that at the adductor pollicis muscle. We conclude that the different pharmacodynamic profiles of mivacurium-induced block at the orbicularis oculi and adductor pollicis muscles were not related primarily to a difference in blood flows.

Edrophonium Antagonism of Intense Mivacurium-Induced Neuromuscular Block in Children

We have studied the time course of recovery after administration of edrophonium during intense mivacurium block in children aged 2-10 yr, using thumb acceleration in response to train-of-four (TOF) stimulation. Forty-three children receiving alfentanil, propofol, nitrous oxide, isoflurane anaesthesia and mivacurium 0.2 mg kg-1 were allocated randomly to one of three groups. Patients in group 1 (n = 15) received edrophonium 1 mg kg-1, 2 min after maximum block (intense block group). At the time of administration of edrophonium in this group, there was no response to TOF stimulation (100% block) and the post-tetanic count was 10.7 (range 0-20). Patients in group 2 received the same dose of edrophonium after 10% recovery of the first twitch (T1) in the TOF (conventional reversal). Patients in group 3 (n = 13) recovered spontaneously. All patients developed complete suppression of twitch height in response to the bolus dose of mivacurium. All recovery times were measured from the point of maximum block after mivacurium. Mean time for 25% recovery of T1 (clinical duration) was 3.8 (SD 1.1) min in the intense block group. This was significantly shorter than the conventional reversal (8.3 (2.4) min) and spontaneous recovery (9.2 (3.5) min) groups (P

Relationship of the Train-of-four Fade Ratio to Clinical Signs and Symptoms of Residual Paralysis in Awake Volunteers

Recovery of the train-of-four (TOF) ratio to a value > 0.70 is synonymous with adequate return of neuromuscular function, but there is little information available concerning the subjective experience that accompanies residual neuromuscular block wherein the TOF ratio is in the range of 0.70 to 0.90. Ten American Society of Anesthesiologists' (ASA) physical status 1 volunteers were studied. Control measurements including grip strength in kilograms and ability to perform a 5-s head- and leg-lift. In addition, a standard wooden tongue depressor was placed between each subject's incisor teeth, and he or she was told not to let the investigator remove it. All subjects were easily able to retain the device despite vigorous attempts to dislodge it. Neuromuscular function was monitored with a Datex (Datex Medical Instrumentation, Inc., Tewksbury, MA) 221 electromyographic (EMG) monitor. TOF stimulation was given every 20 s, and the measured TOF fade ratio was continuously recorded. A 5 mg/kg bolus of mivacurium was then administered, and an infusion at 2 mg.kg-1.min-1 was begun. The infusion was continued until the TOF ratio decreased to < 0.70 and was adjusted to keep it in the range of 0.65 to 0.75. Signs and symptoms of weakness were recorded when the TOF ratio had been stable +/-0.03 for at least 10 min during an interval when there were no adjustments in the infusion. All tests noted previously were repeated at this time. The TOF ratio was then allowed to recover to 0.85-0.90. When stable at this level, all tests were repeated, and the infusion was discontinued. TOF measurements were continued until a ratio of 1.0 was attained and until a final set of observations was recorded. The TOF ratio in all subjects was reduced to < 0.70. No volunteers required intervention to maintain a patient airway, and the hemoglobin oxygen saturation while breathing air was > or = 96% at all times. TOF ratios < or = 0.90 were accompanied by diplopia and difficulty in tracking moving objects in all subjects. The ability to strongly oppose the incisor teeth did not return until the TOF ratio (on average) exceeded 0.85. A sustained 5-s head-lift was not achieved until the TOF ratio averaged 0.60 (range, 0.45-0.75). At a TOF ratio of 0.70, grip strength averaged 59% of control (range, 50-75%). With certain exceptions (vision, ability to clench the teeth tightly), there was wide variation in symptomatology between patients for any given TOF ratio. It is impossible to give reliable TOF break-points at which symptoms and signs will be present or absent. All subjects had significant signs and symptoms of residual block at a TOF ratio of 0.70; none considered themselves remotely "street ready" at this time. The authors believe that satisfactory recovery of neuromuscular function after mivacurium-induced neuromuscular block requires return of the TOF ratio to a value > 0.90 and ideally to unity.

Interaction of Magnesium Sulfate with Mivacurium-induced Neuromuscular Block in Rabbits

Interaction of Magnesium Sulfate with Mivacurium-induced Neuromuscular Block in Rabbits

Effects of Pseudocholinesterase, Anticholinesterase, and 4-Aminopyridine to the Mivacurium-induced Neuromuscular Block on Rat Diaphragm

Effects of Pseudocholinesterase, Anticholinesterase, and 4-Aminopyridine to the Mivacurium-induced Neuromuscular Block on Rat Diaphragm

Vecuronium or Pancuronium as a Priming Agent is Effective to Shorten the Onset of Mivacurium-Induced Neuromuscular Block for Endotracheal Intubation

Vecuronium or Pancuronium as a Priming Agent is Effective to Shorten the Onset of Mivacurium-Induced Neuromuscular Block for Endotracheal Intubation

Chronic carbamazepine therapy does not influence mivacurium-induced neuromuscular block

Patients receiving anticonvulsant drugs chronically are relatively resistant to some non-depolarizing neuromuscular blocking drugs. We investigated the influence of chronic carbamazepine therapy on neuromuscular block induced by mivacurium in 20 otherwise healthy individuals undergoing neurosurgical operations, 10 of whom were receiving chronic treatment with carbamazepine and the other 10 served as controls. The median duration of carbamazepine therapy was 22 weeks (range 4-182 weeks). After premedication with oral diazepam, anaesthesia was induced with fentanyl and thiopentone and maintained with 0.5% isoflurane and nitrous oxide in oxygen. The ulnar nerve was stimulated and the evoked electromyogram recorded using a Datex NMT monitor. Mivacurium 0.15 mg kg-1 (2 x ED95) was given as a bolus i.v. Based on the response to the first of four stimuli, lag time, onset-time, times to recovery to 10%, 25%, 50% and 75% of baseline responses and recovery index (RI 25-75%) did not differ between the two groups. We conclude that mivacurium-induced neuromuscular block was not influenced by preceding chronic carbamazepine therapy.

Edrophonium and human plasma cholinesterase combination for antagonism of mivacurium-induced neuromuscular block

We have compared the reversal characteristics of mivacurium after administration of an edrophonium-plasma cholinesterase (PCHE) combination with that produced by each antagonist alone. Forty ASA I adults were given mivacurium 0.15 mg kg-1 during fentanyl-thiopentone-nitrous oxide-isoflurane anaesthesia. TOF stimulation was applied to the ulnar nerve every 12 s, and the force of contraction of the adductor pollicis muscle was recorded. When spontaneous recovery of first twitch height (T1) reached 10% of its initial control value, patients were allocated randomly to one of four groups (n = 10 in each). Neuromuscular function in patients in group 1 (control group) was allowed to recover spontaneously. Patients in groups 2-4, respectively, received edrophonium 1 mg kg-1 (group ED), exogenous PCHE equivalent to activity present in 25 ml kg-1 of human plasma (group PCHE) or edrophonium 1 mg kg-1 with exogenous human PCHE equivalent to the activity present in 25 ml kg-1 of human plasma (combination group). The time to attain a TOF ratio of 0.75 in the combination group was 4.6 (SD 0.9) min. This was shorter (P < 0.01) than that observed in patients in the control (16.8 (3.3) min), ED (8.9 (3.6) min) and PCHE (9.3 (1.6) min) groups. There was no difference in recovery indices between groups ED and PCHE. We have demonstrated that the edrophonium-PCHE combination significantly accelerated recovery of mivacurium-induced block compared with that observed with the use of individual antagonists.

Can Succinylcholine Antagonize Mivacurium-Induced Neuromuscular Block?

Can Succinylcholine Antagonize Mivacurium-Induced Neuromuscular Block?

Sensitivity to Mivacurium in a Patient with Mitochondrial Myopathy

Sensitivity to Mivacurium in a Patient with Mitochondrial Myopathy

Dose Responses for Neostigmine and Edrophonium as Antagonists of Mivacurium in Adults and Children

Reversal of neuromuscular blockade induced with pancuronium, d-tubocurarine, or doxacurium is achieved using smaller doses of neostigmine in adults than in children. Also, pancuronium- and doxacurium-induced blockade is reversed with smaller doses of edrophonium in children than in adults. The purpose of this study was to compare the spontaneous and neostigmine- and edrophonium-assisted recovery of mivacurium-induced neuromuscular block in adults and children. Fifty-four adults, aged 40.1 +/- 10.9 yr, and 54 children, aged 4.9 +/- 0.7 yr, physical status ASA 1-2, were studied during propofol/fentanyl/nitrous oxide anesthesia. A Datex relaxograph was used to monitor the electromyographic response of the adductor pollicis to train-of-four stimulation of the ulnar nerve every 10 s. After induction of anesthesia, 0.2 mg x kg(-1) intravenous mivacurium was administered followed by an infusion to maintain 90-95% T1 block. At the end of surgery, one of four doses of neostigmine (5, 10, 20, and 50 micrograms x kg(-1)) or edrophonium (100, 200, 400, and 1,000 micrograms x kg(-1)) or placebo was given, by random allocation, when T1 had recovered to 10%. Values of T1 and train-of-four were measured for 10 min. Spontaneous recovery proceeded more rapidly in children than in adults. At 10 min, T1 had recovered to 97 +/- 2% (SD) in children compared with 69 +/- 11% in adults and train-of-four to 84 +/- 5% versus 30 +/- 13% (P<0.0001). In children, 10 min after reversal, recovery of T1 and train-of-four was not different from control after edrophonium and was enhanced only by the larger doses of neostigmine. In adults, recovery was accelerated by both edrophonium and neostigmine. Five minutes after reversal, recovery was improved by either drug in adults and in children. Spontaneous recovery from mivacurium- induced neuromuscular block is more rapid in children than in adults. Ten minutes after attempted reversal, recovery is accelerated by edrophonium and usually by neostigmine in adults but not in children. Thus, when reversal is required, edrophonium may be preferred to neostigmine.

Edrophonium antagonism of intense mivacurium-induced neuromuscular block in children

We have studied the time course of recovery after administration of edrophonium during intense mivacurium block in children aged 2-10 yr, using thumb acceleration in response to train-of-four (TOF) stimulation. Forty-three children receiving alfentanil, propofol, nitrous oxide, isoflurane anaesthesia and mivacurium 0.2 mg kg-1 were allocated randomly to one of three groups. Patients in group 1 (n = 15) received edrophonium 1 mg kg-1, 2 min after maximum block (intense block group). At the time of administration of edrophonium in this group, there was no response to TOF stimulation (100% block) and the post-tetanic count was 10.7 (range 0-20). Patients in group 2 received the same dose of edrophonium after 10% recovery of the first twitch (T1) in the TOF (conventional reversal). Patients in group 3 (n = 13) recovered spontaneously. All patients developed complete suppression of twitch height in response to the bolus dose of mivacurium. All recovery times were measured from the point of maximum block after mivacurium. Mean time for 25% recovery of T1 (clinical duration) was 3.8 (SD 1.1) min in the intense block group. This was significantly shorter than the conventional reversal (8.3 (2.4) min) and spontaneous recovery (9.2 (3.5) min) groups (P < 0.001). The times for 75% and 90% recovery of T1 were shorter in the intense block group (9.4 (2.8), 12.3 (4.2) min) compared with the conventional (13.1 (3.8), 17.3 (4.8) min) and spontaneous recovery (14.9 (4.5), 17.9 (5.2) min) groups (P < 0.01). Total recovery time required for 70% recovery of the TOF ratio (T4/T1) was 8.8 (2.4) min in the intense block group. This was significantly shorter than the conventional reversal (11.9 (3.2) min) (P < 0.05) and spontaneous recovery (17.1 (4.0) min) groups (P < 0.001). Conventional reversal was associated with a shorter total recovery time compared with spontaneous recovery (P < 0.01). The recovery index (time interval between T1 25% and 75%) was comparable in groups 1-3 (5.5 (2.0), 4.8 (2.1) and 5.7 (1.4) min respectively). Ten minutes after development of maximum block, the numbers of patients who recovered adequately (TOF ratio 70% or more) were, respectively, 12 (80%), 8 (53%) and 1 (8%) in groups 1-3. We conclude that edrophonium antagonized intense (no response to TOF stimulation) mivacurium-induced block in children, with significant reduction in the recovery times of T1 and TOF ratio compared with conventional reversal and spontaneous recovery.