Influence of disease progression on the neuromuscular blocking effect of mivacurium in children and adolescents with Duchenne muscular dystrophy.
BACKGROUND
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.


METHODS
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.


RESULTS
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.


CONCLUSIONS
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.
Department of Anesthesiology, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany.
Harald
H
Ihmsen
Joachim
J
Schmidt
Helmut
H
Schwilden
Hubert J
HJ
Schmitt
Tino
T
Muenster
D000293:Adolescent; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D018450:Disease Progression; D006801:Humans; D007546:Isoquinolines / Q000008:administration & dosage / Q000009:adverse effects*; D008297:Male; D000077590:Mivacurium; D020388:Muscular Dystrophy, Duchenne / Q000175:diagnosis / Q000503:physiopathology*; D019148:Neuromuscular Blockade / Q000009:adverse effects* / Q000379:methods
D007546:Isoquinolines; D000077590:Mivacurium