How to rapidly reverse atracurium (a non-depolarizing neuromuscular blocking agent) to facilitate extubation?

Rapid Reversal of Atracurium for Extubation

For rapid reversal of atracurium to facilitate extubation, administer neostigmine (0.04 mg/kg) with atropine (0.02 mg/kg) when there are at least 4 responses to train-of-four (TOF) stimulation at the adductor pollicis muscle, and continue monitoring until TOF ratio reaches ≥0.9. 1, 2

Assessment of Neuromuscular Blockade

• Before attempting reversal, assess the depth of neuromuscular blockade using quantitative TOF monitoring at the adductor pollicis muscle 1, 2
• Neostigmine should only be administered when there are at least 4 responses to TOF stimulation 1, 2
• If fewer than 4 TOF responses are present, wait and maintain anesthesia until adequate spontaneous recovery occurs 1

Pharmacological Reversal

• Once 4 TOF responses are detected, administer:
  • Neostigmine 0.04 mg/kg IV 1, 2
  • Atropine 0.02 mg/kg IV (to prevent cholinergic side effects) 1, 2
• For very slight residual blockade (TOF ratio >0.6), consider reducing the neostigmine dose to 0.02 mg/kg to avoid paradoxical weakness 1
• Complete reversal typically occurs within 10-20 minutes after neostigmine administration 1, 2

Post-Reversal Monitoring

• Continue quantitative monitoring of neuromuscular function until TOF ratio reaches at least 0.9 1
• Do not rely solely on clinical signs (adequate tidal volume) as they are not reliable indicators of complete neuromuscular recovery 3
• Respiratory muscles may recover faster than peripheral muscles, but this doesn't indicate complete reversal 3

Important Considerations

• Atracurium has a duration of action of approximately 20-35 minutes, with spontaneous recovery beginning around this time 4
• Complete spontaneous recovery (95%) typically occurs approximately 60-70 minutes after initial injection 4
• Unlike steroidal neuromuscular blocking agents (rocuronium, vecuronium), atracurium cannot be reversed with sugammadex 1, 2
• Atracurium is eliminated through Hofmann elimination and ester hydrolysis, which are non-organ-dependent pathways, making it suitable for patients with renal/hepatic failure 1

Cautions and Pitfalls

• Administering neostigmine when TOF ratio is already >0.9 may actually impair neuromuscular transmission and upper airway patency 1, 2
• Neostigmine cannot effectively reverse profound or deep neuromuscular blockade - always ensure adequate spontaneous recovery before administration 2
• Inhalational anesthetics (especially isoflurane and enflurane) potentiate atracurium's effects and prolong neuromuscular blockade by approximately 35% 4
• Rare instances of breathing difficulties have been reported following attempted pharmacological antagonism of atracurium-induced neuromuscular block, possibly related to incomplete reversal 4

Algorithm for Atracurium Reversal

1. Monitor neuromuscular function using quantitative TOF monitoring 1, 2
2. If TOF shows fewer than 4 responses: wait and maintain anesthesia 1
3. Once 4 TOF responses are detected: administer neostigmine (0.04 mg/kg) with atropine (0.02 mg/kg) 1, 2
4. Continue monitoring until TOF ratio reaches ≥0.9 (typically 10-20 minutes) 1, 2
5. Once TOF ratio ≥0.9 is achieved, proceed with extubation 1, 2