Comparison of hemodynamic, clinicopathologic, and gastrointestinal motility effects and recovery characteristics of anesthesia with isoflurane and halothane in horses undergoing arthroscopic surgery.

This research study compares the effects of two types of anesthesia – halothane and isoflurane – on the cardiovascular system, clinical pathologies, gastrointestinal motion and recovery characteristics of horses undergoing arthroscopic surgery. Findings indicate that isoflurane may be more beneficial due to greater cardiovascular stability, less organ and muscle damage, and faster restoration of normal intestinal movement after anesthesia.

Research Methodology

• The study involved eight healthy adult horses.
• The horses underwent anesthesia with either isoflurane or halothane in a crossover study design.
• Several cardiopulmonary variables and related derived values were recorded at six different intervals during anesthesia and surgery.
• The recovery from anesthesia was monitored and gastrointestinal tract motility was subjectively observed for 72 hours after anesthesia.
• Chromium was administered to the horses and the fecal chromium concentration was used to measure intestinal transit time.
• Venous blood samples were taken before and at 2, 24, and 48 hours after anesthesia for clinicopathological analysis.

Key findings

• Compared to horses anesthetized with halothane, the horses anesthetized with isoflurane had higher cardiac index, oxygen delivery, and heart rate and a lower systemic vascular resistance.
• Both types of anesthesia had similar effects on mean arterial blood pressure and the dose of dobutamine required to maintain blood pressure.
• The quality and duration of recovery from anesthesia did not differ between the two groups, although recovery times were slightly shorter with isoflurane.
• Following isoflurane anesthesia, gastrointestinal motility normalized sooner and the intestinal transit time of chromium was shorter than that observed after halothane anesthesia.
• Horses given halothane showed increased serum aspartate transaminase and glutamate dehydrogenase activities compared to those given isoflurane, but there were no other significant differences in clinicopathologic variables between the groups.

Conclusion

• This research suggests that, compared to halothane, isoflurane appears to offer better hemodynamic stability during anesthesia, cause less liver and muscle damage, and allow a quicker return to normal intestinal motility after anesthesia in horses undergoing arthroscopic procedures, making it potentially a more effective choice of anesthetic in these situations.