Dose response, recovery, and cost of doxacurium as a continuous infusion in neurosurgical intensive care unit patients

Objectives: To determine the optimal dosing of doxacurium as a continuous infusion in neurosurgical patients with traumatic brain injury; to determine the effects of bolus administration of doxacurium on heart rate (HR), blood pressure (BP), and intracranial pressure (ICP); to monitor neuromuscular recovery after discontinuation of prolonged doxacurium infusion; and to compare the cost of doxacurium with other current neuromuscular blocking drugs. Design: Prospective, open-label study. Setting: Neurosurgical intensive care unit (ICU) of a university-affiliated teaching hospital. Patients: Eight critically ill, mechanically ventilated patients with traumatic head injury and normal renal and hepatic function. Patients had ICP monitoring. Interventions: A bolus injection of doxacurium (0.05 mg/kg) followed by a continuous infusion (0.015 mg/kg/hr), adjusted to maintain one twitch during Train-of-Four nerve stimulation of the adductor pollicis muscle. Measurements and Main Results: Bolus injections of doxacurium did not alter the HR, BP, or ICP. Patients were paralyzed 66 +/- 12 (SEM) hrs, with recovery of the fourth twitch occurring 118 +/- 19 mins after infusion of the doxacurium was discontined. There were no incidences of prolonged weakness, myopathy, or other adverse events. Conclusions: Continuous infusion of doxacurium provides stable neuromuscular blockade for neurosurgical patients with traumatic brain injury. Doxacurium is devoid of clinically important interactions with HR, BP, or ICP and is less costly than other neuromuscular blockers used in the ICU.