What is the recommended use and dosage of Atracurium (Atracurium besylate) for facilitating endotracheal intubation and skeletal muscle relaxation during surgery or mechanical ventilation?

Atracurium for Endotracheal Intubation and Skeletal Muscle Relaxation

Atracurium besylate at 0.4-0.5 mg/kg IV is the recommended initial dose for facilitating endotracheal intubation in most adults, providing good to excellent intubation conditions within 2-2.5 minutes, with clinically effective neuromuscular blockade lasting 20-35 minutes under balanced anesthesia. 1

Dosing for Intubation

Standard Adult Dosing

• Initial bolus: 0.4-0.5 mg/kg IV (1.7-2.2 times ED95) for nonemergency intubation 1
• Maximum neuromuscular block occurs at 3-5 minutes after injection 1
• For airway obstruction with adequate anesthetic depth: 0.1-0.2 mg/kg is sufficient 2, 3

Modified Dosing Based on Anesthetic Agent

• With isoflurane or enflurane: Reduce initial dose by one-third to 0.25-0.35 mg/kg due to potentiation 1
• With halothane: Smaller reductions (approximately 20%) may be considered 1
• Balanced anesthesia: Use standard 0.4-0.5 mg/kg dose 1

Special Populations

• Pediatric patients ≥2 years: No dose adjustment required 1
• Infants (1 month to 2 years) under halothane: 0.3-0.4 mg/kg 1
• Cardiovascular disease or histamine sensitivity: 0.3-0.4 mg/kg given slowly or divided over one minute 1
• Renal or hepatic failure: No dose modification required due to organ-independent elimination via Hofmann elimination and ester hydrolysis 2, 3, 4

Maintenance Dosing During Surgery

Intraoperative Maintenance

• Maintenance dose: 0.08-0.10 mg/kg for prolonged procedures 1
• First maintenance dose typically required 20-45 minutes after initial injection 1
• Subsequent doses at 15-25 minute intervals under balanced anesthesia (slightly longer with isoflurane/enflurane) 1
• No cumulative effect, allowing regular dosing intervals 1
• Higher doses (up to 0.2 mg/kg) permit longer maintenance intervals 1

Continuous Infusion for ICU

• Initial infusion rate: 2.5-3 μg/kg/min for critically ill patients requiring mechanical ventilation 2
• Adjust based on train-of-four (TOF) monitoring 2
• Recovery of TOF ratio >0.7 occurs within 34-85 minutes after discontinuation 2

Clinical Applications and Indications

Strongly Recommended Uses

• Abdominal laparotomy or laparoscopy surgery (GRADE 1+ recommendation) 2, 3
• Facilitating tracheal intubation to reduce pharyngeal/laryngeal injury (GRADE 1+ recommendation) 2
• ENT laser surgery (GRADE 2+ recommendation) 2, 3

Advantages in Specific Clinical Scenarios

• Preferred in renal or hepatic failure (GRADE 2+ recommendation) due to organ-independent elimination 3, 4
• Minimal cardiovascular effects at standard doses 2
• Predictable recovery profile independent of organ function 2

Critical Monitoring Requirements

Neuromuscular Monitoring

• Intraoperative monitoring is strongly recommended (GRADE 1+ recommendation) 2, 3
• Use peripheral nerve stimulator with TOF monitoring to optimize dosing and minimize over/underdosage 1
• Monitor corrugator supercilii muscle when possible, as it reflects laryngeal muscle sensitivity 3

Recovery Parameters

• Recovery to 25% of control: 35-45 minutes under balanced anesthesia 1
• Recovery to 95% complete: approximately 60 minutes 1
• Reversal with neostigmine is prompt and adequate 5

Important Safety Considerations and Pitfalls

Administration Precautions

• Never administer before unconsciousness is induced to avoid patient distress 1
• Do not mix with alkaline solutions (e.g., barbiturates) in the same syringe 1
• Intravenous route only—intramuscular administration causes tissue irritation 1

Histamine Release

• Histamine release occurs at higher doses, potentially causing cardiovascular effects 2, 4
• Use divided or slower administration in patients with cardiovascular disease or histamine sensitivity 1

Laudanosine Concerns

• Laudanosine (breakdown product) has been associated with CNS excitation at extremely high doses 2, 4
• Theoretical seizure risk with prolonged high-dose infusions or hepatic failure (laudanosine is hepatically metabolized) 2
• Only one reported case of seizure in surgical patient receiving atracurium 2
• This concern is primarily theoretical in standard clinical practice 2

Comparison with Alternatives

• Onset time: Slower than succinylcholine (90.9 seconds vs. faster with succinylcholine) but can be optimized with priming technique 5, 6
• Priming technique: Administer 0.06 mg/kg three minutes before intubating dose of 0.44 mg/kg to reduce onset time to 42 seconds 6
• For rapid sequence induction, 1 mg/kg atracurium provides acceptable intubation conditions within one minute in 56.7% of cases 7