What are the recommended doses of atracurium (Atracurium besylate) for induction and maintenance of neuromuscular blockade?

Atracurium Dosing for Induction and Maintenance of Neuromuscular Blockade

For induction of neuromuscular blockade, atracurium should be administered at 0.4-0.5 mg/kg IV bolus, followed by maintenance doses of 0.08-0.10 mg/kg every 20-45 minutes as needed based on train-of-four monitoring. 1

Induction Dosing

The FDA-approved dosing for atracurium provides clear guidance:

• Standard induction dose: 0.4-0.5 mg/kg IV bolus 1

  • This dose is 1.7-2.2 times the ED95 (effective dose for 95% neuromuscular blockade)
  • Provides good to excellent intubation conditions within 2-2.5 minutes
  • Maximum blockade occurs approximately 3-5 minutes after injection
  • Clinical duration of action is typically 20-35 minutes under balanced anesthesia

• Special populations:

  • Patients with significant cardiovascular disease: Reduced dose of 0.3-0.4 mg/kg given slowly or in divided doses over one minute 1
  • Pediatric patients (2 years and older): Same as adult dosing
  • Infants (1 month to 2 years): 0.3-0.4 mg/kg under halothane anesthesia 1

• Anesthetic considerations:

  • When using isoflurane or enflurane: Reduce dose by approximately one-third (0.25-0.35 mg/kg) due to potentiation effects 1
  • With halothane: Smaller dose reductions may be considered 1

Maintenance Dosing

• Intermittent bolus dosing: 0.08-0.10 mg/kg IV 1

  • First maintenance dose typically required 20-45 minutes after initial injection
  • Subsequent doses needed approximately every 15-25 minutes under balanced anesthesia
  • Slightly longer intervals under isoflurane or enflurane
  • Higher maintenance doses (up to 0.2 mg/kg) allow for longer dosing intervals 1

• Continuous infusion:

  • Adult infusion rate: 0.53 mg/kg/hour (approximately 9-10 μg/kg/minute) 2
  • Neonates (up to 1 month): 25% lower dose at 0.40 mg/kg/hour 2

Monitoring and Administration Considerations

• Use peripheral nerve stimulation (train-of-four monitoring) to guide dosing and prevent overdosage or underdosage 1
• Do not administer before unconsciousness has been induced 1
• Do not mix with alkaline solutions (e.g., barbiturate solutions) in the same syringe 1
• Administer intravenously only; intramuscular administration is not recommended 1

Clinical Pharmacology Considerations

• Atracurium is an intermediate-acting neuromuscular blocking agent 3
• Metabolism occurs via ester hydrolysis and Hofmann elimination, independent of renal or hepatic function 3, 4
• Recovery to 25% of control typically occurs 35-45 minutes after injection 1
• Recovery is usually 95% complete approximately 60 minutes after injection 1
• Minimal cardiovascular effects at standard doses, though higher doses (>0.5 mg/kg) may cause histamine release 3, 4
• Laudanosine, a breakdown product, has been associated with CNS excitation with extremely high doses or in hepatic failure 3

Cautions and Pitfalls

• Histamine release can occur at higher doses, potentially causing cardiovascular effects 3
• Always ensure adequate sedation and analgesia before administration 1
• For rapid sequence induction, higher doses (0.75-1.0 mg/kg) may be required but increase the risk of histamine-related side effects 5
• Avoid cumulative effects by using appropriate monitoring to guide dosing intervals 4
• Consider cisatracurium as an alternative when histamine release is a concern, as it has minimal cardiovascular effects and less tendency for mast cell degranulation 3, 6