Pulmonary shunting by the bronchial artery in the anaesthetized horse.
In the quietly standing horse the bronchial arterial blood flow is low, 0.1-0.2% of the pulmonary arterial flow. In horses anaesthetized with halothane, the bronchial arterial flow is reduced by a greater fraction than that in the pulmonary artery. Thus the shunting through the bronchial circulation is decreased about 3-fold by anaesthesia, and cannot, therefore, contribute significantly to the increased alveolar-arterial gradient seen in dorsal recumbency. The results indicate bronchial vasoconstriction under anaesthesia.
Gleed
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RD
Department of Clinical Science, New York State College of Veterinary Medicine, Cornell University, Ithaca 14853.
Dobson
A
A
Hackett
R P
RP
D000758:Anesthesia; D000818:Animals; D001794:Blood Pressure; D001981:Bronchial Arteries / Q000502:physiology*; D006221:Halothane / Q000494:pharmacology; D006736:Horses / Q000502:physiology*; D007649:Ketamine / Q000494:pharmacology; D010477:Perfusion; D011651:Pulmonary Artery / Q000502:physiology*; D011652:Pulmonary Circulation; D013484:Supination; D014991:Xylazine / Q000494:pharmacology
D014991:Xylazine; D007649:Ketamine; D006221:Halothane