Korean J Anesthesiol.  1996 Jun;30(6):649-657. 10.4097/kjae.1996.30.6.649.

Effect of Esmolol upon Sodium Nitroprusside-Induced Hypotension under Halothane Anesthesia in Dog : Impact on the Hemodynamic Parameters and the Sodium Nitroprusside Dose Requirement

• Sohn JT
• Woo MG
• Lee KH

• KMID: 1934793
• DOI: http://doi.org/10.4097/kjae.1996.30.6.649

Abstract

BACKGROUND: The induced hypotension was used to decrease blood loss, thereby decreasing the need for blood transfusion and/or improving operating conditions at the surgical site. It was hypothesized that SNP-induced hypotension with fixed concomitant esmolol infusion(75 ug/kg/min) might prevent side effects such as reflex tachycardia and reduce SNP dose requirement during SNP-induced hypotension. METHOD: The concomitant infusion of 75 ug/kg/min esmolol was used to potentiate hypotension(30% reduction of mean arterial blood pressure) induced with sodium nitroprusside in six dog during halothane(lvo1%)-N2O(50%)-O2(50%) anesthesia. Mean arterial blood pressure, heart rate, cardiac output, mean pulmonary arterial blood pressure, central venous pressure, arterial blood gas analysis, and mixed venous oxygen saturation were measured and systemic vascular resistance was calculated in the each periods. RESULT: The results run as follows; 1) Compared to SNP-induced hypotension, there was significant reduction in SNP dose requirement to maintain a 30% reduction of mean arterial pressure at the concomitant infusion of 75 ug/kg/min esmolol. 2) There were significant reduction in heart rate, mixed venous oxygen saturation and cardiac output, but significant increase in systemic vascular resistance and mean pulmonary arterial pressure at the coneomitant infusion of 75 ug/kg/min esmolol. 3) No rebound hypertension was observed at 30 minute after SNP and esmolol infusions were simultaneously discontinued.
CONCLUSION
The result of present study suggests that esmolol infusion is a safe and effective pharmacologic means of potentiating SNP-induced hypotension during halothane-N2O-O2 anesthesia. Probably esmolol may act by counteracting side effects such as acute tolerance during SNP-induced hypotension.

Keyword

Induced hypotension; esmolol; sodium nitroprusside

MeSH Terms

Anesthesia*
Animals
Arterial Pressure
Blood Gas Analysis
Blood Transfusion
Cardiac Output
Central Venous Pressure
Dogs*
Halothane*
Heart Rate
Hemodynamics*
Hypertension
Hypotension*
Nitroprusside*
Oxygen
Reflex
Sodium*
Tachycardia
Vascular Resistance
Halothane
Nitroprusside
Oxygen
Sodium