What is the recommended maintenance dose of rocuronium (neuromuscular blocking agent) in adult and pediatric patients?

Maintenance Dose of Rocuronium in Adult and Pediatric Patients

For adults, rocuronium maintenance should be administered as intermittent boluses of 0.1-0.2 mg/kg when 25% recovery of T1 is reached, or as continuous infusion starting at 10-12 mcg/kg/min, adjusted to train-of-four (TOF) monitoring. 1, 2

Adult Maintenance Dosing

Intermittent Bolus Technique

• Administer 0.1-0.2 mg/kg at 25% recovery of control T1 (defined as 3 twitches of train-of-four), which provides a median clinical duration of 12-24 minutes under opioid/nitrous oxide/oxygen anesthesia 2
• The mean dose required to maintain 80% blockade in critically ill adults is approximately 0.34 mg/kg 1
• Maintenance boluses of 25 mg can be given when TOF shows 2 responses in trauma patients 1

Continuous Infusion Technique

• Initiate infusion at 10-12 mcg/kg/min only after early evidence of spontaneous recovery from the intubating dose 2
• Infusion rates typically range from 4-16 mcg/kg/min, adjusted based on TOF monitoring 2
• Starting infusion after substantial return of neuromuscular function (>10% of control T1) may require additional bolus doses to maintain adequate blockade 2
• In critically ill patients, the median infusion rate required to maintain one twitch is approximately 10 mcg/kg/min 1

Anesthetic Interaction Considerations

• With volatile anesthetics (enflurane or isoflurane), reduce infusion rate by 30-50% at 45-60 minutes after the intubating dose due to potentiation of neuromuscular blockade 2, 3
• Isoflurane results in longer clinical duration and lower maintenance dose requirements (384 ± 127 mcg/kg/hr) compared to propofol (636 ± 191 mcg/kg/hr) 3

Pediatric Maintenance Dosing

With Sevoflurane/Isoflurane Anesthesia

• Administer bolus doses of 0.15 mg/kg at reappearance of T3 in all pediatric age groups 2
• Alternatively, continuous infusion at 7-10 mcg/kg/min can be administered at reappearance of T2, with the lowest dose requirement for neonates (birth to <28 days) and highest for children (>2 years to 11 years) 2

With Halothane Anesthesia

• For patients 3 months through adolescence, administer maintenance doses of 0.075-0.125 mg/kg upon return of T1 to 25%, providing clinical relaxation for 7-10 minutes 2
• Alternatively, continuous infusion initiated at 12 mcg/kg/min upon return of T1 to 10% (one twitch present in train-of-four) can be used 2

Age-Specific Considerations

• Neonates (birth to <28 days): Longest time to maximum block, require lowest infusion rates 2
• Infants (28 days to 3 months): Shortest time to maximum block, longest duration after intubating dose 2
• Children (>2 years to 11 years): Shortest duration of clinical relaxation, highest maintenance dose requirements 2
• The ED95 is greatest in children (409 ± 71 mcg/kg) compared to infants (251 ± 73 mcg/kg) and adults (350 ± 77 mcg/kg) 4

Critical Monitoring Requirements

Train-of-Four Monitoring is Mandatory

• Quantitative neuromuscular monitoring must be used when administering rocuronium infusions and continued until TOF ratio ≥0.9 is obtained 5
• Adjust infusion rate according to the patient's twitch response monitored with peripheral nerve stimulator 2
• Failure to monitor can lead to overdosing or inadequate blockade, with residual neuromuscular blockade occurring in an estimated 28% of pediatric patients 5

Recovery Timing

• After continuous infusion, TOF response typically returns approximately 60 minutes after stopping the infusion 5, 6
• Spontaneous recovery proceeds at rates comparable to those following similar total doses administered by repetitive bolus injections 2

Special Population Adjustments

Geriatric Patients (≥65 years)

• No differences in duration following maintenance doses compared to younger patients, though slightly prolonged median clinical duration after initial dosing 2
• Greater sensitivity in some older individuals cannot be ruled out 2

Patients with Renal or Hepatic Impairment

• Mean clinical duration is approximately 1.5 times longer in patients with hepatic disease compared to normal function 2
• Patients with renal failure may have greater variation in duration of effect 2
• Consider using benzylisoquinoline muscle relaxants (atracurium/cisatracurium) instead; if rocuronium must be used, do not modify initial dose but expect potentially prolonged duration 5

Obese Patients

• Dose based on actual body weight, not ideal body weight 2
• Dosing based on ideal body weight results in longer time to maximum block, shorter clinical duration, and inadequate intubating conditions 2

Critical Safety Considerations

Concurrent Medications Required

• Rocuronium provides no sedation, analgesia, or amnesia; appropriate sedative and analgesic medications must be administered concurrently 5

Drug Interactions

• Inhalational anesthetics potentiate rocuronium's effect 5
• Anticonvulsants may increase maintenance requirements 1, 5
• Patients on pyridostigmine require 50-75% reduction in subsequent dosing (though initial dose should not be modified) 5

Reversal Considerations

• Sugammadex is the preferred reversal agent, with doses adjusted to depth of blockade: 2 mg/kg at TOF count of 2-4, or 4 mg/kg at post-tetanic count of 1-2 1
• Neostigmine (0.04 mg/kg) with atropine (0.02 mg/kg) can be used when TOF count = 4, with efficacy in 10-20 minutes 1