Korean J Anesthesiol.  1997 Jun;32(6):887-894. 10.4097/kjae.1997.32.6.887.

Effects of Sodium Nitroprusside and Nitroglycerin on the Venous Capacitance during Induced Hypotension in Halothane Anesthetized Dogs

• Sohn JT
• Ahn HY
• Kim SH

• KMID: 2237749
• DOI: http://doi.org/10.4097/kjae.1997.32.6.887

Abstract

BACKGROUND
Since a change in venous capacitance significantly alters venous return and thus affects cardiac output, it is important to know the effects of vasodilators on venous capacitance. The purpose of this study was to examine the effects of sodium nitroprusside and nitroglycerin on venous capacitance during induced hypotension in halothane anesthetized dogs.
METHODS
Fourteen mongrel dogs(SNP group: 7, NTG group: 7), weighing 10~15 kg, were anesthetized with N2O 1.5L/min-O2 1.5L/min-halothane 0.5vol%. Each dog received only one drug. In dogs anesthetized with N2O-O2-halothane, mean arterial pressure(MAP) was decreased by 15%(mild hypotension) and 30%(deep hypotension) of control value by sodium nitroprusside(SNP) and nitroglycerin (NTG), respectively. Venous capacitance was assessed before and during induced hypotension by measuring mean circulatory filling pressure(MCFP). MCFP was measured after arresting the circulation by tightening of superior vena cava and inferior vena cava snares simultaneously.
RESULTS
As compared with MCFP before induced hypotension, MCFP was significantly decreased by SNP at deep hypotension and NTG at mild hypotension and deep hypotension. As compared with MCFP at mild hypotension, MCFP at deep hypotension was significantly decreased by NTG and SNP, respectively.
CONCLUSIONS
These results suggest that NTG has potent venodilating effect at mild and deep induced hypotension, whereas SNP has venodilating effect only at deep induced hypotension.

Keyword

Anesthetic technique; induced hypotension; Monitoring; mean circulatory filling pressure; Pharmacology; nitroglycerin; sodium nitroprusside

MeSH Terms

Animals
Cardiac Output
Dogs*
Halothane*
Hypotension*
Nitroglycerin*
Nitroprusside*
Pharmacology
SNARE Proteins
Sodium*
Vasodilator Agents
Vena Cava, Inferior
Vena Cava, Superior
Halothane
Nitroglycerin
Nitroprusside
SNARE Proteins
Sodium
Vasodilator Agents