What is the recommended maintenance dose of rocuronium (a non-depolarizing neuromuscular blocking agent) for a patient with potential impaired renal or hepatic function undergoing craniectomy excision of a mass?

Rocuronium Maintenance Dosing for Craniectomy with Mass Excision

For intraoperative maintenance of neuromuscular blockade during craniectomy, administer rocuronium 0.1-0.2 mg/kg as needed based on train-of-four monitoring, with no dose adjustment required even in patients with renal or hepatic impairment.

Maintenance Dosing Strategy

Standard maintenance dosing of rocuronium during cranial surgery should follow these principles:

• Administer 0.1-0.2 mg/kg boluses when neuromuscular monitoring indicates recovery of neuromuscular function 1
• This represents approximately one-third to one-half of the initial intubating dose and provides adequate surgical relaxation 2
• Redosing intervals typically occur every 20-40 minutes depending on the initial dose used (0.6 mg/kg provides approximately 36 minutes of clinical duration, while 0.4 mg/kg provides 21 minutes) 2

Monitoring Requirements

Quantitative neuromuscular monitoring is essential for optimal rocuronium management:

• Monitor train-of-four (TOF) responses at the adductor pollicis or corrugator supercilii muscle throughout the procedure 1, 3
• Redose when TOF count returns to 2-4 twitches to maintain adequate surgical conditions 1
• The corrugator supercilii is particularly useful in cranial surgery as it has kinetics comparable to laryngeal muscles and remains accessible 3

Special Considerations for Organ Dysfunction

Rocuronium requires no dose modification in renal or hepatic failure, though clinical considerations apply:

• While atracurium is probably recommended over rocuronium for patients with severe renal or hepatic failure due to organ-independent elimination 3, rocuronium remains acceptable
• If rocuronium is used in organ dysfunction, maintain standard dosing but expect potentially prolonged duration of action requiring careful monitoring 3
• No specific dose reduction is mandated by current guidelines for maintenance dosing in organ failure 3

Reversal Planning

Plan for adequate reversal time at case conclusion:

• If using neostigmine for reversal, ensure TOF count of 4 is present and allow minimum 10 minutes between neostigmine administration (0.04 mg/kg with atropine 0.02 mg/kg) and extubation 1, 4
• If using sugammadex, dose according to depth of blockade: 2 mg/kg for moderate block (TOF count ≥2), 4 mg/kg for deep block (post-tetanic count 1-2), or 8 mg/kg for immediate reversal 1
• Quantitative monitoring to TOF ratio ≥0.9 is mandatory before extubation to prevent residual neuromuscular blockade 1, 4

Common Pitfalls

Avoid these errors in rocuronium maintenance:

• Never rely on clinical assessment alone without neuromuscular monitoring, as this commonly results in postoperative residual blockade 4
• Do not overdose based on body weight in obese patients; use ideal body weight for dosing calculations 4
• Reduce doses in elderly patients (>55 years) and female patients to prevent excessive duration 4
• Ensure adequate time for reversal agent to work before attempting extubation, particularly with neostigmine which requires 10-20 minutes for full effect 1