The Role of Expiratory Muscle Strength Training in Dysphagia Treatment

Educational Objectives

The goal of this program is to improve management of dysphagia with expiratory muscle strength training (EMST). After hearing and assimilating this program, the clinician will be better able to:

1. Compare outcomes among EMST devices.
2. Improve swallow safety in patients using EMST.

Summary

Expiratory muscle strength training (EMST): this is a device-driven therapy that relies on exercising or overloading the muscles of exhalation to create gains of maximal expiratory pressure (MEP); it uses a specific exercise to improve respiratory muscle function in the internal intercostal and abdominal muscles

EMST and swallowing: a part of swallowing relies on coordinating breathing and the apnea period to facilitate better pressure for propulsion and for airway protection; if the protection is impaired (eg, vocal fold paralysis, deficits in strength from stroke or degenerative disease), it may increase the chance of bolus entering the airway; strengthening MEP with EMST can help chronic penetrators and aspirators to clear their airway, reducing their penetration aspiration scale score, and increasing swallow safety; research indicates that EMST increases submental suprahyoid muscle activation; thus, it may impact hyoid elevation and upper esophageal sphincter opening, and improve swallow safety (limited evidence; further research is needed)

Isocapnic hyperpnea trainer: this device is used primarily in research laboratories and requires a demanding respiratory excursion; it measures 60% to 90% maximal voluntary ventilation and gas exchange; it has low clinical utility (large size; expensive)

Incentive spirometer: this is a common EMST device provided mostly to encourage deeper breathing and bronchial hygiene, but it is not considered resistance training as the forces required to perform exercises with the incentive spirometer do not cause overload

Pressure threshold trainer: it has clinical benefit, allows for overload, and can be a reliable measure of progress; it relies on achieving a specific level of air pressure to release a valve inside the device and can be tracked over time; EMST 150 has a pressure threshold range of 30 to 150 cmH20 and EMST 75 has a lower pressure range of 0 to 75 cmH20; the device is smaller, handheld, portable, and affordable; recommendation — “the power of fives”, ie, 5 sets of 5 breaths, 5 days a week for 5 wk

OMNI-perceived exertion scale: this is used while establishing the patient’s initial pressure threshold goal; it is a collection of category scales that rate perceived exertion

Resistance-based trainer (eg, Airofit, Bigbreathe, The Breather): its cost is comparable to EMST 150 or 75; it incorporates exhalation and inhalation into one device (vs separate inhaler adapter required for EMST 150); there is no specific threshold of air pressure the patient has to achieve; it targets airflow rate over a period of time; the demand on the respiratory muscles is lower; it does not specifically target MEP; the device can be used for patients with generalized weakness related to degenerative disease or long-COVID (as it is easier to use; can be a stepping stone to the threshold device); an application helps to track the practice and allows the user to choose between strengthening and endurance programs

Candidates for EMST: these devices can be used for patients with degenerative diseases (eg, amyotrophic lateral sclerosis, multiple sclerosis, and Parkinson disease), other chronic conditions (eg, chronic obstructive pulmonary disease), diaphragmatic paralysis, ventilator dependency, and head and neck cancer (HNC) who have radiation fibrosis and radiation associated aspiration (chronic aspirators); though EMST devices did not significantly change swallowing, quality of life, efficiency, or improve diet in patients with radiation-associated aspiration after HNC, there were improvements in swallow safety and ability to clear aspirated material (Hutcheson et al [2018]); van Sluis et al (2020) found EMST to be a feasible and safe option after total laryngectomy; they demonstrated improvements in MEP

Contraindications: EMST is not recommended for patients with recent or acute stroke, untreated hypertension, untreated gastroesophageal reflux, reactive airway disease (eg, uncontrolled asthma), pregnancy, a history of collapsed lung, recent head and neck surgery, or myasthenia gravis; consulting with the referring physician or specialist can help clarify any potential patient reservations in using EMST

Readings

Hutcheson KA, Barrow MP, Plowman EK, et al. Expiratory muscle strength training for radiation-associated aspiration after head and neck cancer: a case series. Laryngoscope. 2018;128(5):1044-1051. doi:10.1002/lary.26845; Laciuga H, Rosenbek JC, Davenport PW, et al. Functional outcomes associated with expiratory muscle strength training: narrative review. J Rehabil Res Dev. 2014;51(4):535-546. doi:10.1682/JRRD.2013.03.0076; Park JS, Oh DH, Chang MY, et al. Effects of expiratory muscle strength training on oropharyngeal dysphagia in subacute stroke patients: a randomised controlled trial. J Oral Rehabil. 2016;43(5):364-372. doi:10.1111/joor.12382; van Sluis KE, Kornman AF, Groen WG, et al. Expiratory muscle strength training in patients after total laryngectomy; a feasibility pilot study. Ann Otol Rhinol Laryngol. 2020;129(12):1186-1194. doi:10.1177/0003489420931889.

Disclosures

For this program, members of the faculty and planning committee reported nothing relevant to disclose.

Acknowledgements

Dr. Wilson was recorded at the Johns Hopkins Dysphagia Symposium 2024, held September 20-21, 2024, in Baltimore, MD, and presented by Johns Hopkins. For information on upcoming CME activities from this presenter, please visit Hopkinscme.cloud-cme.com. Audio Digest thanks the speakers and presenters for their cooperation in the production of this program.

CME/CE INFO

Accreditation:

The Audio- Digest Foundation is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.

The Audio- Digest Foundation designates this enduring material for a maximum of 0.50 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Audio Digest Foundation is accredited as a provider of continuing nursing education by the American Nurses Credentialing Center's (ANCC's) Commission on Accreditation. Audio Digest Foundation designates this activity for 0.50 CE contact hours.

Lecture ID:

OT581003

Expiration:

This CME course qualifies for AMA PRA Category 1 Credits™ for 3 years from the date of publication.

Instructions:

To earn CME/CE credit for this course, you must complete all the following components in the order recommended: (1) Review introductory course content, including Educational Objectives and Faculty/Planner Disclosures; (2) Listen to the audio program and review accompanying learning materials; (3) Complete posttest (only after completing Step 2) and earn a passing score of at least 80%. Taking the course Pretest and completing the Evaluation Survey are strongly recommended (but not mandatory) components of completing this CME/CE course.

Estimated time to complete this CME/CE course:

Approximately 2x the length of the recorded lecture to account for time spent studying accompanying learning materials and completing tests.