A Pilot Study to Evaluate Efficacy and Safety of Clevidipine in Neurosurgical Patients

This protocol describes a study to gain experience in the use of Clevidipine for perioperative blood pressure control in patients undergoing craniotomy for brain tumor or epilepsy focus resection. The purpose of this study is to establish the efficacy of Clevidipine for intraoperative blood pressure control in patients undergoing intracranial procedures, and gather information on the dosage and adverse effects of Clevidipine in neurosurgical patients. This initial pilot experience serves to familiarize the investigators with the use of this drug prior to initiating a planned randomized trial versus institutional standard-of-care therapy. The investigators will obtain greater familiarity with the dosing of clevidipine in this patient population and collect information on the incidence of adverse effects.

Clevidipine, a recently introduced, short-acting, vascular-selective calcium antagonist, could be a potentially useful adjuvant for neurosurgical cases. It decreases arterial blood pressure by reducing systemic vascular resistance with no effect on venous capacitance vessels (7). Clevidipine was successfully used for the treatment of hypertension in cardiac surgical patients (8). However, there is no information available on its efficacy and safety in patients undergoing intracranial surgery. The perioperative course of patients undergoing intracranial surgery is frequently complicated by acute hypertensive episodes. Acute hypertension in neurosurgical patients is associated with intracranial bleeds and prolonged hospital stay (1). Even with current neuroanesthesia management, hemodynamic stability may be challenging, especially in hypertensive patients. An anesthetic technique that improves perioperative hemodynamics without increasing the incidence of undesirable events (such as increased intracranial pressure, prolonged recovery, etc.) is desirable. A number of antihypertensive agents are available to treat perioperative hypertension. Labetalol is commonly used to treat hypertensive episodes in patients undergoing craniotomy, but may not be desirable in certain patient populations because of its low potency, a slow onset of peak effect (2), and unpredictability in dose requirements (3). Esmolol is only mildly effective in treating postoperative hypertension. Perioperative use is further complicated by bradycardia and conduction delay. Nicardipine is more effective than esmolol in controlling postoperative hypertension (4). However, it causes a dose-dependent cerebral vasodilation, inhibition of autoregulation, as well as a high incidence of hypotension (as compared to labetalol) (5). Hydralazine may increase intracranial pressure by as much as 100% and is rarely used as the sole agent in treating hypertension in neurosurgical patients (6).

21 or older, Clevidipine in brain tumor resection, epilepsy focus resection during acute hypertension under general anesthesia

Clevidipine (0.5 mg/ml in 20 % lipid solution) will be administered via peripheral vein using syringe pump; drug infusion will be initiated at 5 mg/hr (10ml/h) and titrated to effect up to a maximum rate of 32 mg/hr when SBP exceeds 130 mm Hg. The anesthesiologist will be allowed to administer the alternative antihypertensive treatment (e.g. labetalol, hydralazine) after achieving a maximum clevidipine infusion rate.

The Primary Endpoint of This Trial is the Proportion of Patients Who Did Not Require Rescue Antihypertensive Medication to Maintain SBP Below 130 mmHg (i.e. Clevidipine is a Sole Antihypertensive Agent Used for Blood Pressure Control)

Inclusion Criteria: Age 21 or older Able to give consent No significant laboratory abnormalities Undergoing elective surgery for tumor resection or epilepsy focus resection Exclusion Criteria: Patients with acute cardiac ischemia, renal or liver dysfunction, unstable hemodynamic, advanced heart block, or pregnancy defective lipid metabolism such as pathologic hyperlipemia, lipoid nephrosis, or acute pancreatitis if it is accompanied by hyperlipidemia; and in patients with severe aortic stenosis will be excluded. Known or suspected allergy to study drug or study drug components,patients with allergies to soybeans, soy products, eggs, or egg products; Participation in other clinical research studies involving the evaluation of other investigational drugs or devices within 30 days of enrollment in this study.