mivacurium and Muscular-Dystrophy--Duchenne

Studies with nondepolarizing neuromuscular blocking agents showed a delayed onset and prolonged recovery in patients with Duchenne muscular dystrophy. The objective of this study was to investigate if these alterations depend on disease progression.. The authors studied 11 children (6-9 yr) with moderate Duchenne muscular dystrophy, 11 adolescents (12-16 yr) with advanced Duchenne muscular dystrophy, and 2 age-matched control groups of 8 patients each (5-9 and 10-17 yr). Anesthesia was performed with propofol and remifentanil. Patients received a single intravenous dose of 0.2 mg/kg mivacurium. Neuromuscular transmission was monitored by acceleromyography. The time course of neuromuscular blockade was characterized by the onset time and the times to different levels of recovery.. Onset and duration of neuromuscular blockade were significantly prolonged in adolescent Duchenne muscular dystrophy patients (onset time, 4.0 min; recovery index, 12.3 min; median), as compared with Duchenne muscular dystrophy children (onset time, 2.3 min; recovery index, 6.8 min), and also as compared with young controls (onset time, 2.0 min; recovery index, 4.4 min) and adolescent controls (onset time, 2.5 min; recovery index, 4.8 min). Within the Duchenne muscular dystrophy patients, onset time and recovery index increased significantly with age. In the control group, age had no effect.. The neuromuscular blocking effects of mivacurium showed a significant age dependency in Duchenne muscular dystrophy patients, which was most probably caused by the progression of the disease.

Topics: Adolescent; Age Factors; Child; Child, Preschool; Disease Progression; Humans; Isoquinolines; Male; Mivacurium; Muscular Dystrophy, Duchenne; Neuromuscular Blockade

Anesthesia may be administered to patients with Duchenne's muscular dystrophy, but cases are reported in which apparently healthy children suffer hyperkalemic cardiac arrest. We present the case of a 5-year-old boy whose muscular dystrophy was discovered following a fatal, perioperative cardiac arrest in the postanesthesia care unit.

Topics: Anesthesia; Anesthetics, Inhalation; Anesthetics, Intravenous; Blood Gas Analysis; Cardiopulmonary Resuscitation; Child, Preschool; Electrocardiography; Electroencephalography; Fatal Outcome; Fentanyl; Heart Arrest; Humans; Hyperkalemia; Isoflurane; Isoquinolines; Male; Methyl Ethers; Mivacurium; Muscular Dystrophy, Duchenne; Neuromuscular Nondepolarizing Agents; Nitrous Oxide; Postoperative Complications; Rhabdomyolysis; Sevoflurane; Vecuronium Bromide

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.

Topics: Adolescent; Anesthesia Recovery Period; Anesthesia, General; Anthropometry; Child; Child, Preschool; Cholinesterases; Humans; Isoquinolines; Male; Mivacurium; Muscular Dystrophy, Duchenne; Neuromuscular Blockade; Neuromuscular Junction; Neuromuscular Nondepolarizing Agents; Orthopedic Procedures; Prospective Studies

Topics: Adolescent; Child; Humans; Isoquinolines; Mivacurium; Muscular Dystrophy, Duchenne; Neuromuscular Blockade; Neuromuscular Nondepolarizing Agents; Surgical Procedures, Operative