Skip Navigation LinksHome > August 1986 - Volume 65 - Issue 2 > Dose-dependent Effects of Bupivacaine on Rat Muscle Arteriol...
Anesthesiology:
ORIGINAL ARTICLE: PDF Only

Dose-dependent Effects of Bupivacaine on Rat Muscle Arterioles.

Johns, Roger A. M.D.; Seyde, Walter C. M.D.; DiFazio, Cosmo A. M.D., Ph.D.; Longnecker, David E. M.D.

Collapse Box

Abstract

The dose-dependent actions of bupivacaine on the microvasculature were evaluated by television microscopy in an in vivo rat cremaster muscle preparation. Animals were anesthetized with chloralose and urethane. Mean arterial pressure was measured via a carotid artery cannula; heart rate was calculated from the phasic pressure trace. The cremaster muscle was suffused with a balanced electrolyte solution that was controlled for temperature, pH, PO2, PCO2, and osmolarity to provide a physiologic environment. Internal diameters of fourth-order arterioles were measured with an electronic vernier displayed on the video monitor. Arteriolar diameters were measured every 30 s during a 10-min control period, a 10-min period of topical application of bupivacaine hydrochloride, and a 30-min recovery period. Bupivacaine 10-1, 100, 101, and 102 [mu]g [middle dot] ml-1 produced progressive vasoconstriction to 82.7 +/- 2.9%, 75.0 +/- 5.6%, 71.0 +/- 7.0%, and 65.7 +/- 9.4% of control (P <= 0.05 for each), respectively. Bupivacaine, 103 and 2.5 X 103 [mu]g [middle dot] ml-1, did not alter arteriolar diameters significantly, although there was a tendency for vasodilation. In a second group of animals, arteriolar diameters were measured during intravenous bupivacaine infusion that produced stable plasma concentrations of 2.3 +/- 0.2 [mu]g [middle dot] ml-1. Vasoconstriction of 91.4 +/- 2.2%, of control (P <= 0.01) was observed. These results demonstrate that dose-dependent arteriolar constriction occurs even with blood bupivacaine levels that are at the upper limits of those expected to occur during regional anesthesia.
(C) 1986 American Society of Anesthesiologists, Inc.
Publication of an advertisement in Anesthesiology Online does not constitute endorsement by the American Society of Anesthesiologists, Inc. or Lippincott Williams & Wilkins, Inc. of the product or service being advertised.
Login

Article Tools

Share

Search for Similar Articles
You may search for similar articles that contain these same keywords or you may modify the keyword list to augment your search.