Effects of buprenorphine on cardiovascular and pulmonary function in clinically normal horses and horses with chronic obstructive pulmonary disease.

The research evaluated how buprenorphine, administered intravenously, impacts the cardiovascular and respiratory functions of both healthy horses and horses suffering from chronic obstructive pulmonary disease (COPD).

Methodology

• The research involved five healthy horses and five horses in either a partial clinical remission from COPD (period A) or experiencing an acute attack of airway obstruction (period B).
• Several tests were performed before and after the intravenous administration of a single buprenorphine, including pulmonary function testing, arterial blood gas analysis, and arterial blood pressure measurements.
• Different parameters were calculated using a pulmonary function computer, including the respiratory rate, tidal volume, the ratio of expiration time to inspiration time, minute expiratory ventilation, maximal change in transpulmonary pressure, dynamic compliance (a measure of lung elasticity), and pulmonary resistance.
• The researchers also measured heart rate and systolic, diastolic, and mean arterial blood pressures.

Results & Interpretation

• The baseline measurements indicated that COPD horses in period A had reduced dynamic compliance and increased respiratory rate, minute expiratory ventilation, change in transpulmonary pressure, and heart rate compared to healthy horses.
• COPD horses in period B had decreased ratios of expiration to inspiration time, arterial blood pH, and oxygen sufficiency, along with increased respiratory rate, minute expiratory ventilation, change in transpulmonary pressure, and pulmonary resistance compared to healthy horses.
• Buprenorphine administration led to increased systolic, diastolic, and mean arterial blood pressures in all horses. The respiratory rate and minute expiratory ventilation increased in healthy horses, while oxygen sufficiency decreased within 60 minutes in COPD horses.

Conclusion

• The results suggest that buprenorphine can cause excitement in unsedated horses or horses without pain signs.
• However, it does not appear to cause severe respiratory depression or adverse cardiovascular effects in either healthy horses or horses with COPD.

This study contributes to our understanding of the impacts of drugs like buprenorphine on horses, particularly those with COPD. The insights could be useful in designing therapeutic strategies and managing the health of horses with respiratory disease.