Effects of pentoxifylline on pulmonary function and results of cytologic examination of bronchoalveolar lavage fluid in horses with recurrent airway obstruction.

The research study investigates the effects of administering Pentoxifylline (PTX), a drug often used for chronic obstructive pulmonary disease, on horses suffering from recurrent airway obstruction (RAO). It found that PTX improved lung function but had varying absorption rates in horses.

Research Methodology

The research involved 10 horses affected by RAO. The test was set up such that:

• 6 horses were given PTX (16 g) mixed with corn syrup
• 4 horses were given only corn syrup, serving as the control group
• The treatment was administered twice daily over a period of 14 days
• Pulmonary function was evaluated on three occasions – before the start of the treatment (day 0), in the middle of the treatment spell (day 8), and at the end of the treatment (day 15)
• Bronchoalveolar lavage (BAL), an investigation method of the lower respiratory tract, was performed on days 0 and 15
• Airway block reversibility was calculated by measuring pulmonary function before and after administering atropine, a drug used to treat certain heart conditions
• Serum concentration of PTX was measured in 4 horses at various points post the administration of the drug over the course of the treatment

Research Findings

The findings of the study included:

• The administration of PTX resulted in a decrease in elastance (a measure of the lung’s ability to return to its initial state after being stretched) by day 8 and both elastance and airway resistance by day 15
• Cytologic examination of BAL fluid did not show significant differences between values for day 0 and day 15, indicating that the cellular makeup and fluid condition within the lungs were left relatively unchanged
• All horses showed a decrease in airway resistance after being administered atropine
• When mixed with corn syrup and given orally, PTX’s absorption in horses was inconsistent, showing noticeable variation in serum PTX levels over time and among horses

Conclusions

The research concluded that high dosage administration of PTX can enhance the respiratory function of horses suffering from RAO, even when kept in unfavorable environmental conditions. However, the differing absorption rates indicate a need for further research to determine optimal delivery methods of administering PTX in horses.