A critical assessment of pulmonary function testing in exercising ponies

Area of Science:

• Equine respiratory physiology
• Pulmonary function testing

Background:

• Accurate assessment of pulmonary function during exercise is crucial for equine athletes.
• Existing methods for measuring airflow and intrathoracic pressure in exercising horses require validation.

Purpose of the Study:

• To evaluate the accuracy and reproducibility of pulmonary function measurements in exercising saddle ponies.
• To assess the influence of a breathing apparatus on respiratory patterns during exercise.

Main Methods:

• Measurements of airflow (V), tidal volume (VT), and pleural pressure (Ppl, Pes) using a pneumotachograph and esophageal balloon catheter in exercising ponies.
• Simultaneous recording of respiratory parameters, electrocardiogram, and limb movements.
• Investigation of esophageal elastance and catheter position effects on pressure measurements.

Main Results:

• Pulmonary function measurements showed good accuracy and reproducibility.
• Maximal intrathoracic pressure and total pulmonary resistance calculated using Ppl and Pes were not significantly different.
• Esophageal pressures (Pes) were closely correlated with pleural pressures (Ppl) (R=0.99).
• The pneumotachograph system demonstrated linear response within the measured airflow range.
• The breathing mask influenced respiratory frequency but not exercise-induced changes.

Conclusions:

• The employed techniques allow for accurate pulmonary function measurements in exercising ponies.
• The breathing apparatus minimally impacts exercise-induced respiratory pattern changes.
• Validated methods support further research into equine exercise physiology.