Transcutaneous Electrical Stimulation and Dysphagia Rehabilitation: A Narrative Review

Abstract

Transcutaneous electrical stimulation (TES) was introduced as a modality for dysphagia rehabilitation more than a decade ago. The underlying premise of this modality is improving the structural movements and enhancing neural activation based on stimulation-induced muscle contractions. However, divisive evidence exists regarding the effectiveness of this treatment modality. This manuscript reviews current evidence regarding the effects of transcutaneous electrical stimulation (TES) on clinical and physiological aspects of swallowing function. Furthermore, this narrative review delineates the knowledge gap in this area and recommends future research roadmap. This review gives a comprehensive picture regarding current knowledge of TES to practicing speech and language pathologists and interested researchers. It highlights the need for more robust studies in this area. It also encourages researchers to focus more on the physiologic studies to understand the physiologic underpinning behind this treatment modality.

Submental transcutaneous electrical stimulation can impact the timing of laryngeal vestibule closure

“…This may not be enough time for CNS to provide adaptation responses to a new perturbation. Future studies are encouraged to test the physiologic effect of TES with an additional number of swallowing trials (i.e., [15][16][17][18][19][20] to better monitor the adaptation of swallowing motor activity to external perturbation from TES.…”

“…Transcutaneous electrical stimulation was primarily purported to strengthen the weaker muscles and re‐educate safe swallowing 15,16 . However, despite significant clinical studies that have been conducted regarding the efficacy of TES on dysphagia treatment, the findings are still inconclusive 17 .…”

“…Transcutaneous electrical stimulation was primarily purported to strengthen the weaker muscles and re-educate safe swallowing. 15,16 However, despite significant clinical studies that have been conducted regarding the efficacy of TES on dysphagia treatment, the findings are still inconclusive. 17 Thus, recent efforts have revolved around a better understanding of the modulating effects of TES parameters on different aspects of swallowing physiology.…”

The Effect of Sensory Level Versus Motor Level Electrical Stimulation of Pharyngeal Muscles in Acute Stroke Patients with Dysphagia: A Randomized Trial

“…In previous studies, use of sensory versus motor NMES resulted in improved clearance of pharyngeal residue and timeliness in swallow, ultimately resulting in improved scores on the PAS [ 11 ]. Improvements in swallow cannot be solely attributed to electrical stimulation as standard of care dysphagia therapy was provided during this time frame [ 41 ].…”

Transcutaneous electrical stimulation as a resistance force in lingual exercise: A preliminary proof‐of‐concept study

“…Studies have reported equivocal evidence regarding the clinical effect of TES on swallowing 1 . While some potential reasons for these controversial reports might be related to research designs of differing rigor, the applied TES protocol or the type of therapy paired with TES, 2,3 the primary limitation may relate to our lack of understanding regarding the effect of TES on swallowing physiology. Understanding the effect of TES parameters on swallowing physiology will help us depict a more comprehensive picture of the benefits and limitations of TES in swallowing rehabilitation.…”