NICARDIPINE VERSUS NITROPRUSSIDE FOR CONTROLLED HYPOTENSION DURING SPINAL SURGERY IN ADOLESCENTS

Nicardipine or nitroprusside was used to induce controlled hypotension in healthy adolescents with idiopathic scoliosis undergoing spinal fu sion. Twenty patients were randomly assigned to the nitroprusside (N) or nicardipine (C) group. All patients received a standardized anesthe tic. A target mean arterial blood pressure (MAP) of 60 mm Hg was achie ved by varying the vasoactive infusions only. Moderate hemodilution (P CV = 25) and intraoperative blood salvage were used in all cases. Hemo dynamic variables, blood loss, occurrence of reflex tachycardia, and r eversibility of the hypotensive state were compared between the two gr oups. Significant differences were observed between the two groups in the amount of blood loss and reversibility of the hypotensive state. G roup C had less blood loss (761 +/- 199 mt) than Group N (1297.5 +/- 2 64, P less than or equal to .05). Time to restoration of baseline MAP was longer with Group C (26.8 +/- 4.0 min) than Group N (7.3 +/- 1.1 m in, P less than or equal to 0.001). Both drugs rapidly achieved a stab le, controlled hypotensive state and an acceptable operating field. Th ere was no statistically significant difference between groups with re spect to the amount of crystalloid administered or urine output. These results suggest that nicardipine is a safe, effective drug for contro lled hypotension in this population and that it may offer the signific ant advantage of reduced blood loss in these patients.