Hemodynamic effects of intravenous midazolam-xylazine-butorphanol in dogs.
The hemodynamic effects of a mixture of midazolam (1.0 mg/kg), xylazine (0.44 mg/kg), and butorphanol (0.1 mg/kg) were evaluated in six adult dogs. The dogs were anesthetized with isoflurane for instrumentation. As the dogs returned to consciousness, baseline values were recorded and the midazolam-xylazine-butorphanol mixture and glycopyrrolate (0.01 mg/kg) were administered intravenously (IV). Hemodynamic data were recorded 3, 10, 20, 30, 40, 50, and 60 minutes after injection. Mean arterial pressure (AP), mean pulmonary arterial pressure (PAP), heart rate (HR), rate-pressure product (RPP), mean pulmonary capillary wedge pressure (PCWP), systemic vascular resistance (SVR), and right ventricular stroke work index (RVSWI) were increased significantly above baseline values. Cardiac output (CO), stroke volume (SV), cardiac index (CI), stroke index (SI), mean central venous pressure (CVP), and left ventricular stroke work index (LVSWI) were decreased significantly below baseline values. When administered IV at the dosages used in this study, midazolam-xylazine-butorphanol-glycopyrrolate induced profound acute alterations in several critical hemodynamic variables.
Gross
M E
ME
Department of Veterinary Clinical Medicine, College of Veterinary Medicine, University of Illinois-Urbana 61801.
Tranquilli
W J
WJ
Thurmon
J C
JC
Benson
G J
GJ
Olson
W A
WA
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002077:Butorphanol / Q000008:administration & dosage / Q000494:pharmacology*; D002302:Cardiac Output / Q000187:drug effects; D002496:Central Venous Pressure / Q000187:drug effects; D004285:Dogs / Q000502:physiology*; D004338:Drug Combinations; D004562:Electrocardiography / Q000662:veterinary; D004569:Electroencephalography / Q000662:veterinary; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D007275:Injections, Intravenous / Q000662:veterinary; D008297:Male; D008874:Midazolam / Q000008:administration & dosage / Q000494:pharmacology*; D009019:Morphinans / Q000494:pharmacology*; D011669:Pulmonary Wedge Pressure / Q000187:drug effects; D013318:Stroke Volume / Q000187:drug effects; D013843:Thiazines / Q000494:pharmacology*; D014655:Vascular Resistance / Q000187:drug effects; D014991:Xylazine / Q000494:pharmacology*
D004338:Drug Combinations; D009019:Morphinans; D013843:Thiazines; D014991:Xylazine; D002077:Butorphanol; D008874:Midazolam