Rocuronium Infusion Dosing Recommendations
The recommended infusion dose for rocuronium is 10-12 mcg/kg/min initially, which should be adjusted based on neuromuscular monitoring to maintain the desired level of neuromuscular blockade. 1
Initial Dosing and Administration
- Rocuronium infusion should only be initiated after early evidence of spontaneous recovery from an intubating dose (typically 0.6 mg/kg) 1
- Due to rapid redistribution of rocuronium, starting the infusion after substantial return of neuromuscular function (more than 10% of control T1) may require additional bolus doses to maintain adequate block 1
- The initial recommended infusion rate is 10-12 mcg/kg/min (equivalent to 0.6-0.72 mg/kg/hour) 1
Dose Adjustment and Monitoring
- The infusion rate must be individualized according to the patient's twitch response as monitored with a peripheral nerve stimulator 1
- In clinical trials, infusion rates have ranged from 4 to 16 mcg/kg/min 1
- For maintenance of approximately 90% neuromuscular blockade, the average requirement is 528-572 mcg/kg/hour (8.8-9.5 mcg/kg/min) during halothane anesthesia 2, 3
- Quantitative neuromuscular monitoring is strongly recommended when administering rocuronium infusions, continuing until a Train-of-Four (TOF) ratio of 0.9 has been obtained to ensure adequate recovery 4
Special Population Considerations
- Patients with multiple organ failure require significantly lower infusion rates (0.2 mg/kg/hour or approximately 3.3 mcg/kg/min) compared to patients without multiple organ failure (0.5 mg/kg/hour or approximately 8.3 mcg/kg/min) 5
- Critically ill patients receiving prolonged infusions may have longer recovery times than surgical patients 6
- Inhalation anesthetics, particularly enflurane and isoflurane, enhance the neuromuscular blocking action of rocuronium, potentially decreasing infusion requirements by as much as 40% 1
- For pediatric patients, infusion rates of 7-10 mcg/kg/min are recommended, with the lowest dose requirement for neonates and highest for children 2-11 years old 1
Recovery Considerations
- After continuous infusion, train-of-four response typically returns about 60 minutes after stopping the infusion 7
- In critically ill patients, median time from end of infusion to recovery of the fourth twitch in TOF is approximately 60 minutes (range 15-155 minutes) 6
- Spontaneous recovery is significantly prolonged in patients with multiple organ failure 5
- Pharmacokinetic studies show that the elimination half-life after infusion in ICU patients (337 minutes) is longer than in surgical patients 6
Common Pitfalls and Caveats
- Failure to monitor neuromuscular function can lead to overdosing or inadequate blockade 4
- Initiating infusion too late after the intubating dose may result in inadequate blockade requiring additional bolus doses 1
- Residual neuromuscular blockade can occur if monitoring is inadequate, with an estimated frequency of 28% in pediatric patients receiving muscle relaxants 8
- Drug interactions can significantly alter dosing requirements - inhalational anesthetics potentiate the effect of rocuronium, while anticonvulsants may increase requirements 4, 1
- Rocuronium provides no sedation, analgesia, or amnesia, so appropriate sedative and analgesic medications must be administered concurrently 7