title: Diltiazem reduces the dose requirement for nitroprusside-induced hypotension.
abstract: The efficacy of diltiazem, a calcium channel blocker, for reducing the dose requirement for nitroprusside-induced hypotension was studied in 20 healthy patients during spine fusion for scoliosis. Anesthesia included methohexital (3 mg/kg followed by 3 mg.kg-1.h-1 intravenously), nitrous oxide, and alfentanil (40 micrograms/kg, followed by 0.7 microgram.kg-1.min-1 intravenously). Patients were assigned randomly to two groups, receiving either nitroprusside alone or nitroprusside and diltiazem (bolus of 80 micrograms/kg with two consecutive infusions of 4.5 micrograms.kg-1.min-1 during the first 30 min and then 1.3 micrograms.kg-1.min-1). Nitroprusside was used to maintain mean arterial pressure at 55-60 mm Hg in both groups. Hypotension was obtained in similar times, 4 min in the group receiving nitroprusside alone (range, 1-8 min) and 2 min in the group receiving nitroprusside and diltiazem (range, 1-8 min). Nitroprusside administration lasted 186 +/- 17 min (mean +/- SEM) in the group receiving nitroprusside alone and 214 +/- 26 min (mean +/- SEM) in the other group (NS). After hypotension, arterial blood pressure returned to its initial value in a time of 7 min in the group receiving nitroprusside alone (range, 5-9 min) and 9 min in the group receiving nitroprusside and diltiazem (range, 7-13 min) (NS). Cumulative doses of nitroprusside were larger in the group receiving nitroprusside alone (0.47 +/- 0.07 mg/kg; mean +/- SEM) than in the other group (0.24 +/- 0.05 mg/kg; mean +/- SEM) (P < 0.01). Significant increase in plasma thiocyanate concentration, cardiac index, and heart rate was observed only in the group receiving nitroprusside alone, but no intergroup differences were found.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Département d'Anesthésie-Réanimation Chirurgicale, Hôtel-Dieu, Nantes, France.
authors.forename: J M
authors.initials: JM
authors.lastname: Bernard
authors.forename: J
authors.initials: J
authors.lastname: Moren
authors.forename: D
authors.initials: D
authors.lastname: Demeure
authors.forename: J L
authors.initials: JL
authors.lastname: Hommeril
authors.forename: N
authors.initials: N
authors.lastname: Passuti
authors.forename: M
authors.initials: M
authors.lastname: Pinaud
mesh_terms: D000328:Adult; D004110:Diltiazem / Q000008:administration & dosage*; D005260:Female; D006439:Hemodynamics / Q000187:drug effects / Q000502:physiology; D006801:Humans; D007023:Hypotension, Controlled; D008297:Male; D009599:Nitroprusside / Q000008:administration & dosage*; D012600:Scoliosis / Q000601:surgery*; D013123:Spinal Fusion / Q000379:methods*
chemical_list: D009599:Nitroprusside; D004110:Diltiazem