Dantrolene for Malignant Hyperthermia 848th FST

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Dantrolene for Malignant Hyperthermia848th FST
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DantroleneDantrium Sodium

• Calcium channel blocker commonly used for
  treatment and pretreatment of Malignant
  Hyperthermia

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Dantrolene

• The agent of choice for treatment of malignant
  hyperthermia (MH)
• It acts directly on the contractile mechanism of
  skeletal muscles by interfering with release of
  calcium by the sarcoplasmic reticulum

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Dantrolene Reactions

• The most serious reaction has been with oral
  administration and a related hepatotoxicity
• Prolonged high doses have been associated with
  hepatic necrosis
• In all cases normal liver function returned after
  discontinuation of the drug

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Dantrolene common side effects

• Dizziness
• Diplopia
• Dysarthria
• Sensation of swelling of the eyeballs and tongue
• Feeling that limb muscles are rubbery
  spaghetti-like and weak
• Decreased proprioception of feet while climbing
  or descending steps
• Nausea, epigastric discomfort, and diarrhea
• Side effects subside within a few days

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Dantrolene

• Marketed in a freeze dried form and must be
  reconstituted with sterile water
• Treatment of MH is by rapid I.V. push of the drug
• Dosage is 1mg/kg and continuing until symptoms
  have begun to subsides
• Temperature begins to fall
• Muscle stiffness begins to subside
• Heart rate begins to decrease
• Or to a maximal dose of 10 mg/kg

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Maintenance

• If symptoms return, previous dosage can be
  repeated every 15 minutes
• Even in absence of recurrence of symptoms,
  loading dose(s) should be followed by infusion of
  1 to 2 mg/kg during each 3 to 4 hour period until
  all evidence of active MH crisis has subsided

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Oral Dantrolene

• Used extensively in pre-treatment of susceptible
  MH patients
• Recommended dosage is 4 mg/kg for 24 to 48 hours
  prior to surgery
• Some clinicians do not use Dantrolene
  prophylacticlly

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References

• Stene, J. K., Grande, C.M. Trauma Anesthesia.
  Williams Wilkins, 1991, Baltimore, Maryland.

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Questions
Jim Malson, CPT