Safety and feasibility of continuous infusion of remifentanil in the neurosurgical intensive care unit

OBJECTIVE: Remifentanil is a selective mu-opioid agonist with a context-sen sitive half-time of 3 to 5 minutes, independent of dose or administration d uration. Other desirable effects include decreased cerebral metabolism and intracranial pressure (ICP) with minimal cerebral perfusion pressure change s. We present six cases illustrating indications for the use of remifentani l in the neurosurgical intensive care unit. METHODS: Patients received bolus doses of remifentanil of 0.05 to 1.0 mu g/ kg, followed by continuous infusions of 0.03 to 0.26 mu g/kg/min, titrated to effect. When infusions were discontinued for neurological examinations, another bolus dose preceded infusion reinstitution. Indications for the use of remifentanil included mean arterial pressure and cerebral perfusion pre ssure decreases with the use of other agents (e.g., codeine or propofol) fo r ICP control, elevated ICP that was refractory to propofol/mannitol treatm ent, agitation that was unresponsive to standard therapies, and coughing th at caused ICP increases after subarachnoid hemorrhage. RESULTS: Three patients experienced spontaneous intracranial bleeding (two cases of subarachnoid hemorrhage and one case of intraventricular hemorrhag e), and three patients exhibited severe traumatic subdural hemorrhage. All patients recovered from the effects of remifentanil within 3 minutes after discontinuation of infusion, which allowed frequent rapid neurological asse ssments. Procedures for pulmonary toilet (i.e., endotracheal suctioning, po stural drainage, and bronchoscopy) were performed without deleterious ICP i ncreases or mean arterial pressure or cerebral perfusion pressure decreases during remifentanil infusions. CONCLUSION: The ultrashort duration of action of remifentanil allowed easy performance of frequent neurological examinations in the neurosurgical inte nsive care unit. No patient experienced deleterious hemodynamic or neurolog ical effects as a result of remifentanil use.