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

Atracurium Dosage and Use for Endotracheal Intubation and Skeletal Muscle Relaxation

For endotracheal intubation and skeletal muscle relaxation during surgery, atracurium should be administered at an initial dose of 0.4 to 0.5 mg/kg intravenously for most adult patients, with maintenance doses of 0.08 to 0.10 mg/kg as needed. 1

Initial Dosing for Intubation

• For routine endotracheal intubation, atracurium 0.4 to 0.5 mg/kg IV (1.7 to 2.2 times the ED95) is recommended, providing good to excellent intubation conditions within 2 to 2.5 minutes 1
• Maximum neuromuscular blockade is achieved approximately 3 to 5 minutes after injection 1
• For patients with significant cardiovascular disease, a reduced initial dose of 0.3 to 0.4 mg/kg is recommended, administered slowly or in divided doses over one minute 1
• When used with inhalational anesthetics, dosage adjustments are necessary:
  • Under isoflurane or enflurane: reduce initial dose by approximately one-third (0.25 to 0.35 mg/kg) 1
  • Under halothane: smaller dose reductions may be considered due to its marginal (20%) potentiating effect 1

Maintenance Dosing

• Maintenance doses of 0.08 to 0.10 mg/kg are recommended during prolonged surgical procedures 1
• First maintenance dose is typically required 20 to 45 minutes after initial injection 1
• Subsequent maintenance doses should be determined by clinical criteria, typically needed every 15 to 25 minutes under balanced anesthesia 1
• Higher maintenance doses (up to 0.2 mg/kg) allow for longer intervals between doses 1
• Atracurium lacks cumulative effects, allowing for relatively regular dosing intervals 1

Special Populations

• Pediatric patients (2 years and older): No dosage adjustments required 1
• Infants (1 month to 2 years): Initial dose of 0.3 to 0.4 mg/kg under halothane anesthesia, with potentially more frequent maintenance dosing 1
• Patients with renal or hepatic failure: No dose modification required due to atracurium's organ-independent elimination via ester hydrolysis and Hofmann elimination 2, 3

Monitoring and Administration

• Peripheral nerve stimulation monitoring is strongly recommended (Grade 1+) to optimize dosing and minimize the risk of overdosage or underdosage 2, 3
• Monitoring the corrugator supercilii muscle provides optimal guidance for dosing due to its comparable kinetics to laryngeal muscles 3
• Atracurium should only be administered after unconsciousness has been induced 1
• Do NOT administer intramuscularly as it may cause tissue irritation 1
• Do NOT mix with alkaline solutions (e.g., barbiturate solutions) in the same syringe or administer through the same needle 1

Clinical Duration and Recovery

• Under balanced anesthesia, clinically required neuromuscular block generally lasts 20 to 35 minutes 1
• Recovery to 25% of control typically occurs 35 to 45 minutes after injection 1
• Recovery is usually 95% complete approximately 60 minutes after injection 1
• Neuromuscular blockade can be readily antagonized with neostigmine 4

Specific Clinical Applications

• Strongly recommended for abdominal laparotomy or laparoscopy surgery (Grade 1+) 2, 3
• Recommended for ENT laser surgery (Grade 2+) 2, 3
• For airway obstruction related to supraglottic devices, a lower dose of 0.1 to 0.2 mg/kg is effective if adequate anesthetic depth is maintained 2

Pharmacological Considerations

• Atracurium is an intermediate-acting non-depolarizing neuromuscular blocking agent of the benzylisoquinolinium group 2, 5
• It is inactivated by ester hydrolysis and Hofmann elimination, making it suitable for patients with renal or hepatic dysfunction 2, 3
• At higher doses, atracurium may cause histamine release with potential cardiovascular effects 2, 5
• Laudanosine, a breakdown product of atracurium, has been associated with central nervous system excitation at extremely high doses, though seizures are rare 2

Cautions and Monitoring

• Intraoperative monitoring of neuromuscular blockade is strongly recommended (Grade 1+) 2
• For morbidly obese patients, dosing based on ideal body weight is recommended to avoid prolonged neuromuscular blockade 6
• When using atracurium in patients with cardiovascular instability, slower administration or divided doses should be considered 1