Comparison of detomidine and romifidine as premedicants before ketamine and halothane anesthesia in horses undergoing elective surgery.

The study compares the use of two premedication drugs, detomidine and romifidine, in horses undergoing surgery. The research concludes that both drugs are suitable for use, however, detomidine may be preferable when maintaining blood pressure is crucial.

Research Methodology

• The study involved 100 client-owned horses undergoing elective surgery. Half of the horses received detomidine hydrochloride while the other half received romifidine as premedicants.
• Both groups of horses were first administered acepromazine before their respective premedicants. Subsequently, they were induced and maintained on anesthesia with ketamine hydrochloride and halothane.
• Vital signs such as arterial blood pressure, blood gases, ECG, and heart and respiratory rates were recorded during the course of the study. Furthermore, the time it took for the horses to fall unconscious (induction) and wake from anesthesia (recovery) were timed and graded.

Research Findings

• The average duration of anesthesia across all horses was approximately 104 minutes. There were no significant differences in the induction and recovery times or grades between the groups.
• The study found a decrease in Mean Arterial Blood Pressure (MABP) in both groups 30 minutes after the start of the anesthesia. However, from 40 to 70 minutes after the start, the MABP in the detomidine-treated horses was significantly higher compared to that in the romifidine-treated horses.
• Interestingly, more horses in the romifidine group received dobutamine infusions, yet they still presented with lower MABP values.
• Vital signs such as mean respiratory rate, PaO2, PaCO2, arterial pH, and heart rate showed no significant differences between the two groups.

Conclusion

• The study concluded that both detomidine and romifidine were satisfactory premedicants for horses undergoing anesthesia for elective surgeries.
• Despite this, romifidine led to more severe hypotension than detomidine, even in the presence of additional dobutamine infusions.
• Thus, while both drugs are acceptable alpha2-adrenoceptor agonists, detomidine may be preferable for use in situations where maintaining blood pressure is particularly important.