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Home / Equine Research Bank / Equine Vet J / Dynamic nasopharyngeal collapse in horses: What we know so f...
Equine veterinary journal2023; doi: 10.1111/evj.14022

Dynamic nasopharyngeal collapse in horses: What we know so far.

Abstract: Dynamic nasopharyngeal collapse (NPC) is an obstructive upper airway disease that affects mainly the inspiratory phase of respiration in horses undergoing strenuous exercise. It occurs when the neuromuscular activity of the nasopharynx is overwhelmed by the intense negative pressures generated during exercise. This leads to collapse of at least one of the four components of the nasopharynx which is comprised of the two lateral walls, the dorsal roof and the ventral soft palate. As a result, the airway diameter and thus airflow become compromised. Even small changes in the airway diameter produces profound increases in negative inspiratory pressure, perpetuating the cycle of collapse. Compared to other dynamic upper respiratory tract disorders, the amount of literature on NPC as a disease entity is limited. The exact pathophysiology of NPC is unknown; however, it impacts up to one quarter of high-performance equine athletes presenting for poor performance. There is currently no definitive treatment for this severely performance-limiting condition. Thus, the prognosis for future athletic prognosis is guarded, with most horses being retired from racing or athletic use in general. Further research is warranted in this field to reduce the impact of disease and in turn, reduce the turnover rate and economic loss by enhancing the career longevity of elite equine athletes diagnosed with NPC.
© 2023 The Authors. Equine Veterinary Journal published by John Wiley & Sons Ltd on behalf of EVJ Ltd.
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Publication Date: 2023-12-12 PubMed ID: 38084762DOI: 10.1111/evj.14022Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research article discusses dynamic nasopharyngeal collapse (NPC), a severe respiratory condition affecting horses during exercise which often restricts their performance and has a significant economic impact due to the premature retirement of these animals from their athletic pursuits.

Overview of the Condition

  • Dynamic nasopharyngeal collapse (NPC) is an ailment that restricts the upper airway in horses, affecting their respiration mainly during the exercise’s inspiratory phase — the inhaling portion of the breathing cycle.
  • This collapse happens when the muscles and nerves in the nasopharynx, the area behind the nose and above the throat, can’t withstand the intense negative pressure created during exercise.
  • The nasopharynx consists of four sections – the two side walls, the upper roof, and the lower soft palate. If any of these components collapses, it results in a decrease in airway diameter and subsequent airflow.
  • Even minor changes in the airway’s size lead to significant increases in negative inspiratory pressure, aggravating the collapse cycle.

Current Understanding and Impact of the Disease

  • Compared to other dynamic upper respiratory tract disorders impacting horses, there is relatively less scientific literature on NPC.
  • The exact cause or pathophysiology of NPC remains unclear, but it affects up to 25% of elite performing horses who show signs of underperformance.

Treatment and Prognosis

  • At present, there is no specific, definitive treatment for this condition, which severely hampers the athletic performance of horses.
  • Due to NPC’s debilitating nature, the prognosis for affected horses is cautious. The majority of them are forced to retire from racing or any athletic activity in general.

The Need for Further Research

  • The paper underlines the critical need for ongoing research in this area to reduce the impact of the disease.
  • Suitable interventions could help lower the rate of premature retirement of horses and the consequent economic losses, and enhance the career longevity of horses diagnosed with NPC.

Cite This Article

APA
Jeong S, Bond SL, Sole-Guitart A. (2023). Dynamic nasopharyngeal collapse in horses: What we know so far. Equine Vet J. https://doi.org/10.1111/evj.14022

Publication

Equine veterinary journal
ISSN: 2042-3306
NlmUniqueID: 0173320
Country: United States
Language: English

Researcher Affiliations

Jeong, Sharon
  • School of Veterinary Science, Faculty of Science, University of Queensland, Gatton, Queensland, Australia.
Bond, Stephanie L
  • School of Veterinary Science, Faculty of Science, University of Queensland, Gatton, Queensland, Australia.
Sole-Guitart, Albert
  • School of Veterinary Science, Faculty of Science, University of Queensland, Gatton, Queensland, Australia.

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