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Contractility Measurements of Human Uterine Smooth Muscle to Aid Drug Development
07:56

Contractility Measurements of Human Uterine Smooth Muscle to Aid Drug Development

Published on: January 26, 2018

Exacerbation of acetazolamide-responsive sodium channel myotonia by uterotonic agents

K Fujii1, H Iranami, Y Hatano

  • 1Department of Anesthesiology, Japanese Red Cross Society, Wakayama Medical Center, Wakayama City, Japan. fujiik@topaz.ocn.ne.jp

International Journal of Obstetric Anesthesia
|November 16, 2010
PubMed

The symptoms of myotonia can worsen during pregnancy and tocolysis with ritodrine has been associated with rhabdomyolysis. We describe a patient with myotonia who developed hypertonus immediately following the administration of uterotonic agents. A 24-year-old, G2P1 at 31 weeks of gestation with a history of acetazolamide-responsive myotonia presented with premature rupture of membranes. During cesarean delivery she experienced significant hypertonus of the upper limbs, shoulders, fingers, and mouth immediately after intravenous administration of oxytocin 5 IU and methylergometrine maleate 0.2mg. The mechanism underlying increased muscle tone in response to these drugs remains unclear. Anesthesiologists should be especially attentive to the administration of uterotonic drugs during the management of pregnant myotonia patients.

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