Esmolol is more effective than sodium nitroprusside in reducing blood loss during orthognathic surgery

The goal of this study was to compare the efficacy of esmolol and sodium nitroprusside (SNP) as primary drugs for producing controlled hypotension and limiting blood loss during orthognathic surgery. Thirty ASA physical status I and II patients (mean age 22 yr) undergoing LeFort I maxillary osteotomies were randomly assigned to receive either esmolol (n = 15) or SNP (n = 15) as the primary drug to induce hypotension. All patients received a balanced anesthetic technique including isoflurane, with controlled hypotension during the downfracture of the maxilla. Patients assigned to the esmolol treatment group received boluses of 500 micrograms/kg of esmolol, followed by a continuous infusion of 100-300 micrograms.kg-1.min-1, and the SNP treatment group received a continuous infusion of SNP at 0.25-4.00 micrograms.kg-1.min-1; both infusions were titrated to obtain a mean arterial blood pressure within the target range of 55-65 mm Hg. The mean arterial blood pressure during the hypotensive period was 58.7 +/- 0.7 (mean +/- SEM) and 61.8 +/- 0.4 mm Hg for esmolol and SNP, respectively (P less than 0.001). In addition, 40% +/- 4% of the observed values in the esmolol group and 53% +/- 3% in the SNP group were outside the target range for mean arterial blood pressure (difference significant at P less than 0.05), and a greater proportion of the deviations were above 65 mm Hg in the SNP group than in the esmolol group (0.64 vs 0.46, respectively, P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)