Anesthesia/anesthetics hemodynamic effects

In the horse, induction with thiopental usually results in a brief increase in heart rate and a decrease in cardiac output but no significant change in arterial blood pressure. Arterial blood pressure is typically lower after thiopental induction than in ketamine-based anesthetic techniques (Bennett et al 1998, Muir et al 2000). However, when horses are placed on inhalation anesthetics for maintenance of anesthesia, the hemodynamic effects of the induction agents is short lived and the hypotension and reduced cardiac output typical of inhalation anesthesia predominates (Bennett et al 1998, Wagner et al 1996). Respiratory depression is significant with an accompanying increase in Paco2 and decrease in pH. 

J. E., Peray, P.A., Desch, G., Sassine, A. and Eledjam, J.J. (1996) Comparative electrophysiologic and hemodynamic effects of several amide local anesthetic drugs in anesthetized dogs. Anesthesia and Analgesia, 82, 648—656. 

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