Chronic lung infections, inflammation, hypersensitivity and bleeding (EIPH) in the horse and the role of palatal instability (PI).

Lung disease in a number of forms is quite common in the equine species and in many cases has a detrimental effect on performance. There are of course numerous causative agents including pathogens and physical and environmental factors. Age and immune state also contribute to the incidence as well as hereditary factors.

There is however another surprisingly common factor that can create lung issues either primarily or by potentially aggravating other pre-existing conditions.

This is of course Palatal Instability (PI). Once the palate becomes unstable this allows air to be taken orally (through the mouth) and this air will carry with it bacteria, feed material and saliva which will be deposited in the airways. There are bacterial species that are at home in the mouth (commensal) but can be pathogenic in the airways. Saliva depending on its PH can cause irritation and inflammation of the pharynx and trachea. Over an extended period of time this lung irritation can weaken the linings of the small airways which will increase the likelihood of vascular rupture and bleeding (Exercise Induced Pulmonary Hemorrhage - EIPH).

The only way to prevent this progressive irritation and pulmonary (lung) degradation  is to stabilize the soft palate and stop the passage of air through the mouth during inspiration (respiratory exercise).

For Treatment see -