Comparison of two expiration training devices for improving swallowing functions in nasopharyngeal cancer survivors

Abstract

Objective: The study aims to compare the effect of expiratory muscle training with and without resistance on swallowing functions in nasopharyngeal cancer (NPC) survivors. Background: NPC survivors often experience changes in pharyngeal and laryngeal functions as the head and neck muscles are often affected following radiotherapy. Increased pharyngeal residue, penetration and aspiration may occur a few years after radiotherapy in NPC survivors. Expiratory muscle strength training (EMST) has been recently proposed as a rehabilitative swallowing exercise for head-and-neck cancer survivors, however, further evidence is needed. Method: Twenty-four NPC survivors were recruited and randomly assigned to one of two groups: a resistance training group (RT) and a no resistance training group (NR). All participants were assessed before and after treatment. The swallowing outcome measures included amount of residue, penetration and aspiration as assessed with fiberoptic endoscopic evaluation of swallowing (FEES). The maximum expiratory pressure and pitch range were also included as outcome measures. Both groups received four weekly training sessions that included tongue exercises, effortful swallow and pitch glide. The RT group was further trained with the EMST 150TM device and the NR group was trained with an exhalation training tool with minimal resistance. Results: The resistance training group had significant improvement in maximum expiratory pressure and pitch range but the same improvement was not observed in the no resistance training group. Both group showed changes in penetration and aspiration. Conclusions: The study suggested that traditional swallowing exercises together with expiratory muscle training with resistance were effective in improving the pharyngeal and laryngeal functions in nasopharyngeal cancer survivors.