Category:

• Muscle relaxant

  Description:

• Curare class, nondepolarizing skeletal muscle relaxant

  Indications:

• Adjunct to general anesthesia to facilitate intubation and skeletal muscle relaxation

• Diagnostic agent for myasthenia gravis

  Contraindications:

• Patients in whom histamine release if a definite hazard.

  Precautions:

• Pregnancy category C

• Only used by skilled personnel in airway management and respiratory support.

• Must have anticholinesterase reversal agents immediately available during use.

• Will cause histamine release.  Use with caution in patients susceptible to histamine, such as cardiovascular disease and asthma.

• May cause bradycardia during anesthesia.

• Use with caution in patients with neuromuscular disease.

• Use in caution in elderly due to increased dosage requirements and recovery times.

• Does not alter consciousness or relieve pain.

• Use a peripheral nerve stimulator to monitor twitch suppression and recovery.

• IM injection may cause tissue irritation.

Adverse Reactions (Side Effects):

• Cardiovascular: arrhythmias, cardiac arrest, bradycardia, hypotension

• Excessive salivation

• Prolonged respiratory suppression

Dosage:

• Administered IV as a sustained injection over 1-1.5 minutes or IM

• Individualize dosage calcualted at 0.1-0.2mg/kg

• General dosing reference:

  • Adult (70kg): 40-60 units IV at time of incision, 20-30 units in 3-5 minutes if required

  • long operations: supplemental doses of 20 units as required (based on 1.1 units/kg)

  • Electroshock therapy (EST): 1.1 units/kg

  • Myasthenia gravis diagnosis:

  • administer 1/15 to 1/5 of EST dose

  • exaggerated response will occur

  • reverse effect with neostigmine

• Children: 0.6mg/kg

• Neonates: 0.3mg/kg