Bristol Veterinary School, University of Bristol, Langford, Bristol, BS40 5DU, UK.
University of Adelaide, School of Animal and Veterinary Sciences, Roseworthy Campus, Mudla Wirra Rd, Roseworthy, SA 5371, Australia.
Vet J. 2021 Sep;275:105708. doi: 10.1016/j.tvjl.2021.105708. Epub 2021 Jun 17.
Exercise-induced upper airway collapse (UAC) probably occurs when the stabilising muscles of the upper airway are unable to withstand the dramatic changes in airflow and pressure that occurs during exercise. In racehorses, the mainstay of treatment is surgical intervention. In human athletes, exercise-induced laryngeal obstruction has been treated successfully with inspiratory muscle training (IMT). The aims of this study were: (1) to assess the feasibility of IMT in racehorses; and (2) describe the exercising endoscopy findings pre- and post-IMT in racehorses diagnosed with dynamic UAC. Horses undergoing IMT wore a mask with an attached threshold-valve to apply an additional load during inspiration, creating a training stimulus with the purpose of increasing upper airway muscle strength. Each horse underwent IMT once daily, while standing in the stable, 5-6 days/week for 10 weeks. Endoscopy recordings were analysed in a blinded manner using an objective grading scheme and subjective pairwise analysis. Seventeen horses successfully completed the IMT protocol, with full information available for 10 horses. Objective grading analysis showed a lower grade of vocal fold collapse (6/9 horses), palatal instability (7/10 horses) and intermittent dorsal displacement of the soft palate (5/7 horses) post-IMT. Pairwise subjective analysis suggested better overall airway function post-IMT in 3/10 horses. The main limitations of this preliminary investigation were the low number of horses examined and lack of a control population. Further research is required to investigate the effects of IMT on upper airway muscle strength and to evaluate its efficacy for prevention and treatment of UAC.
运动引起的上气道塌陷（UAC）可能发生在上气道稳定肌无法承受运动期间气流和压力的剧烈变化时。在赛马中，主要的治疗方法是手术干预。在人类运动员中，通过吸气肌训练（IMT）成功治疗了运动诱发的喉阻塞。本研究的目的是：（1）评估 IMT 在赛马中的可行性；（2）描述诊断为动态 UAC 的赛马中 IMT 前后的运动内窥镜检查结果。接受 IMT 的马匹佩戴带有附加阈压阀的面罩，以便在吸气时施加额外的负载，从而产生训练刺激，以增加上气道肌肉力量。每匹马每周 5-6 天，每天站立在马厩中进行 IMT，持续 10 周。使用客观分级方案和主观配对分析对内窥镜记录进行盲法分析。17 匹马成功完成了 IMT 方案，其中 10 匹马的信息完整。客观分级分析显示，声带塌陷（9 匹马中有 6 匹）、腭不稳定（10 匹马中有 7 匹）和软腭间歇性背侧移位（7 匹马中有 5 匹）在 IMT 后分级较低。配对主观分析表明，3/10 匹马的气道整体功能在 IMT 后有所改善。本初步研究的主要局限性是检查的马匹数量较少，且缺乏对照组。需要进一步研究来调查 IMT 对上气道肌肉力量的影响，并评估其预防和治疗 UAC 的效果。
