Inspiratory muscle training for the treatment of dynamic upper airway collapse in racehorses: A preliminary investigation.

Authors: Fitzharris L E, Franklin S H, McConnell A K, Hezzell M J, Allen K J

Journal: Veterinary journal (London, England : 1997)

DOI: 10.1016/j.tvjl.2021.105708 PubMed: 34147643Log in to save

Summary

# Editorial Summary: Inspiratory Muscle Training for Upper Airway Collapse in Racehorses Dynamic upper airway collapse during exercise likely results from inadequate strength in the stabilising musculature to cope with the extreme pressure and airflow changes of high-speed work, yet surgical intervention remains the standard treatment approach in racing practice despite its risks and variable outcomes. Fitzharris and colleagues investigated whether inspiratory muscle training (IMT)—a technique already proven effective for exercise-induced laryngeal obstruction in human athletes—could feasibly be applied to horses, using a threshold-valve mask device worn in the stable to load the inspiratory muscles over a 10-week period at 5–6 sessions weekly. Of 17 horses that completed the protocol, objective endoscopic analysis revealed improvements in 6 of 9 horses for vocal fold collapse, 7 of 10 for palatal instability, and 5 of 7 for intermittent dorsal displacement of the soft palate, though subjective overall airway function improvement was noted in only 3 of 10 horses. Whilst the findings are encouraging and suggest IMT warrants further investigation as a non-surgical intervention option, the small sample size and absence of a control group limit the strength of these preliminary conclusions. Practitioners should await larger, controlled trials before incorporating IMT into routine management protocols, though this approach may eventually offer valuable preventative or adjunctive benefits for horses predisposed to airway dysfunction.

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Practical Takeaways

•Inspiratory muscle training via threshold-valve mask may offer a non-surgical alternative for managing upper airway collapse in racehorses, though efficacy requires further validation
•The protocol is feasible for practical implementation in stabled horses (once daily, 5-6 days/week for 10 weeks) with objective improvements in some airway structures
•Current evidence is preliminary; surgical intervention remains the established treatment and IMT should not replace conventional management without further research

Key Findings

•17 horses successfully completed 10 weeks of daily inspiratory muscle training using a threshold-valve mask
•Objective grading showed improvement in vocal fold collapse (6/9 horses), palatal instability (7/10 horses), and intermittent dorsal displacement of soft palate (5/7 horses) post-IMT
•Subjective pairwise analysis suggested better overall airway function post-IMT in 3/10 horses
•Study was limited by small sample size and absence of control population

Conditions Studied

exercise-induced upper airway collapsedynamic upper airway collapsevocal fold collapsepalatal instabilitydorsal displacement of soft palate

Related References

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