Effects of intravenously administered glycopyrrolate in anesthetized horses.

This research investigates the impact of a drug, glycopyrrolate, on the heart rate (HR) and blood pressure (BP) in anesthetized horses, documenting that this medication can provide improvement in both parameters.

Objective and Methodology

• The goal of this study was to evaluate the outcomes of intravenous glycopyrrolate on heart rates (HR) and blood pressure (BP) in anesthetized horses, particularly those with a low HR (less or equal to 30 beats/min).
• Seventeen horses were included in the study and randomly administered either glycopyrrolate at a dosage of 2.5 micrograms/kg body weight (BW) or a saline solution intravenously.

First Trial of Glycopyrrolate Effects

• After the first administration of glycopyrrolate, if HR did not increase by more than 5 beats/min within 10 minutes, the same dose of the drug was re-administered.
• Following the initial glycopyrrolate treatment, heart rate increased by more than 5 beats/min in only 3 of the 9 horses treated, suggesting a limited immediate response to the drug.
• Overall changes in HR and mean BP were not significantly different after this round, but the systolic and diastolic BP significantly increased. The researchers identified this increase as significant with P-value less than 0.025 using the Bonferroni corrected paired t-test.

Second Trial and Sequential Treatments

• On the second treatment, an increased heart rate of more than 5 beats/min was observed in 3 out of 7 horses given 2.5 micrograms/kg BW glycopyrrolate, and 4 out of 5 horses given a total dose of 5.0 micrograms/kg BW. This represented a significant difference in response.
• There was a notable increase in BP after the 2.5 micrograms/kg BW treatment but not after the 5.0 micrograms/kg BW one.

Conclusion

• The final increase in HR, of more than 5 beats/min, was associated with a significant rise in BP. The researchers identified this as significant with P-value less than 0.05 using an unpaired t-test.
• From the study results, the researchers concluded that heart rate can be increased with 2.5 to 5.0 micrograms of glycopyrrolate per kg of body weight, administered intravenously, with the results showing improvement in blood pressure in anesthetized horses. Thus, glycopyrrolate might be useful as a clinical tool in managing anesthetized horses showing lower HR.