Interventional procedure overview of electrical stimulation of the pharynx for neurogenic dysphagia

Article

Number of patients/ follow up

Direction of conclusions

Reasons for non-inclusion in summary of key evidence section

Bath PM, Lee HS and Everton LF. (2018) Swallowing therapy for dysphagia in acute and subacute stroke. The Cochrane database of systematic reviews 10:cd000323

Systematic review and meta-analysis

n=4 studies

Moderate- and low-quality evidence suggests that swallowing therapy did not have a significant effect on the outcomes of death or dependency/disability, case fatality at the end of the trial, or penetration aspiration score. However, swallowing therapy may have reduced length of hospital stay, dysphagia, and chest infections, and may have improved swallowing ability. However, these results are based on evidence of variable quality, involving a variety of interventions. Further high-quality trials are needed to test whether specific interventions are effective.

More recent systematic reviews included.

Beirer S, Grisold W and Dreisbach J. (2020) Therapy-resistant dysphagia successfully treated using pharyngeal electrical stimulation in a patient with the pharyngeal-cervical-brachial variant of the Guillain-Barre syndrome. eNeurologicalSci 20:100255

Case report

n=1

FU=18 days

PES was safe and may be beneficial in other neurologic disorders, where traditional dysphagia therapies have proved unsuccessful.

Studies with more people or longer follow up included.

Chiang CF, Lin MT, Hsiao MY et al. (2019) Comparative Efficacy of Noninvasive Neurostimulation Therapies for Acute and Subacute Poststroke Dysphagia: A Systematic Review and Network Meta-analysis. Archives of Physical Medicine and Rehabilitation 100(4):739-50e4

Systematic review and meta-analysis

n=3 studies

Among the 4 noninvasive neurostimulation therapies, rTMS, tDCS, and sNMES were effective for treating poststroke dysphagia; furthermore, rTMS may be the most effective therapy according to probability ranking.

More recent systematic reviews included.

Ebihara S and Naito T. (2022) A Systematic Review of Reported Methods of Stimulating Swallowing Function and their Classification. The Tohoku journal of experimental medicine 256(1):1-17

Systematic review

n=15 studies

PES with a catheter electrode has been shown to be useful in early recovery from post-stroke dysphagia and other various conditions of dysphagia including post-tracheal intubation.

Meta-analyses included.

Essa H, Vasant DH, Raginis-Zborowska A et al. (2017) The BDNF polymorphism Val66Met may be predictive of swallowing improvement post pharyngeal electrical stimulation in dysphagic stroke patients. Neurogastroenterology and motility: the official journal of the European Gastrointestinal Motility Society 29(8)

RCT post hoc analysis

n=36 (18 active treatment)

FU=3 months

Our findings suggest an association between BDNF and stimulation induced swallowing recovery. Further work will be required to validate these observations and demonstrate clinical utility in patients.

RCT (Vasant, 2016) included.

Everton LF, Benfield JK, Michou E et al. (2022) Reliability of the Penetration-Aspiration Scale and Temporal and Clearance Measures in Poststroke Dysphagia: Videofluoroscopic Analysis From the Swallowing Treatment using Electrical Pharyngeal Stimulation Trial. Journal of speech, language, and hearing research: JSLHR 65(3):858-68

RCT post hoc analysis

n=18

Analysis of interrater reliability for analysis of penetration-aspiration scale scores. Interrater reliability for PAS is acceptable but depends on how the PAS scores are handled in the analysis. Interrater reliability for most temporal measures was high, although some measures required additional training. No clearance measures had excellent reliability.

RCT (Bath, 2016) included.

Everton LF, Benfield JK, Michou E et al. (2021) Effects of Pharyngeal Electrical Stimulation on Swallow Timings, Clearance and Safety in Post-Stroke Dysphagia: Analysis from the Swallowing Treatment Using Electrical Pharyngeal Stimulation (STEPS) Trial. Stroke Research and Treatment: 5520657

RCT post hoc analysis

n=81 (43 active treatment)

This study, which conducted additional measurements of kinematic and residue analysis on the STEPS data did not detect "missed" improvements in swallowing function that the PAS is not designed to measure. However, more studies with greater numbers are required.

RCT (Bath, 2016) included.

Florea C, Braumann C, Mussger C et al. (2020) Therapy of dysphagia by prolonged pharyngeal electrical stimulation (Phagenyx) in a patient with brainstem infarction. Brain Sciences 10(5):256

Case report

n=1

We present a case of brainstem infarction with severe dysphagia in a 53-year-old woman with preserved cognitive functions. Though the swallowing improved, she stayed tube-dependent with minimal attempts with puréed food during therapy, and could not be decannulated.

Studies with more people or longer follow up included.

Jayasekeran V, Singh S, Tyrrell P et al. (2010) Adjunctive functional pharyngeal electrical stimulation reverses swallowing disability after brain lesions. Gastroenterology 138(5):1737-46

RCT

n=28 (16 active treatment)

FU=2 weeks

This pilot study of PES confirms that it is a safe neurostimulation intervention that reverses swallowing disability after virtual lesion or stroke.

Studies with more people or longer follow up included. Included in systematic reviews and meta-analyses.

Kesik G and Ozdemir L. (2021) Non-pharmacologic approaches to dysphagia in patients with multiple sclerosis: A systematic review. Turk Noroloji Dergisi 27(2):111-6

Systematic review

n=1 study

One study was identified that used PES to treat dysphagia associated with multiple sclerosis.

The study identified (Restivo, 2013) was included in the key evidence.

Koestenberger M, Neuwersch S, Hoefner E et al. (2020) A Pilot Study of Pharyngeal Electrical Stimulation for Orally Intubated ICU Patients with Dysphagia. Neurocritical care 32(2):532-8

Cohort study

n=40 (15 active treatment)

This study demonstrated the benefits of PES in ICU patients still orally intubated, thus offering a potential new method to reduce morbidity, mortality, and economic burden in a mixed ICU population.

Studies with more people or longer follow up included.

Michou E, Mistry S, Jefferson S et al. (2014) Characterizing the mechanisms of central and peripheral forms of neurostimulation in chronic dysphagic stroke patients. Brain stimulation 7(1):66-73

RCT

n=6 (had both active and sham)

FU=30 days

The 2 neurostimulation paradigms, PES and PAS, which mainly employ peripheral stimulation, showed associated increases in cortical excitability of the affected hemisphere.

Studies with more people or longer follow up included. Included in systematic reviews and meta-analyses.

Muhle P, Suntrup-Krueger S, Bittner S et al. (2017) Increase of Substance P Concentration in Saliva after Pharyngeal Electrical Stimulation in Severely Dysphagic Stroke Patients - an Indicator of Decannulation Success? Neuro-Signals 25(1):74-87

Before-and-after study

n=23

FU=35 days

The physiological mechanism of PES may consist in restoration of sensory feedback, which is known to be crucial for the execution of a safe swallow. Substance P possibly acts as a biomarker for indicating response to PES.

Studies with more people or longer follow up included.

Scutt P, Lee HS, Hamdy S, and Bath PM. (2015) Pharyngeal Electrical Stimulation for Treatment of Poststroke Dysphagia: Individual Patient Data Meta-Analysis of Randomised Controlled Trials. Stroke Research and Treatment 429053

Systematic review and meta-analysis

n=3 studies

PES was associated with less radiological aspiration and clinical dysphagia and possibly reduced length of stay in hospital across three small trials.

More recent systematic reviews included.

Suntrup S, Marian T, Schroder JB et al. (2015) Electrical pharyngeal stimulation for dysphagia treatment in tracheotomized stroke patients: a randomized controlled trial. Intensive care medicine 41(9):1629-37

RCT

n=30 (20 active treatment)

In this pilot study, PES enhanced remission of dysphagia as assessed with fiberoptic endoscopic evaluation of swallowing, thereby enabling decannulation in 75% of patients.

Studies with more people or longer follow up included. Included in systematic reviews and meta-analyses.

Traugott M, Hoepler W, Kitzberger R et al. (2021) Successful treatment of intubation-induced severe neurogenic post-extubation dysphagia using pharyngeal electrical stimulation in a COVID-19 survivor: a case report. Journal of medical case reports 15(1):148

Case report

n=1

PES treatment contributed to the restoration of a safe swallowing function in this critically ill patient with COVID-19 and ICU-acquired swallowing dysfunction.

Studies with more people or longer follow up included.

Vasant DH, Michou E, O'Leary N et al. (2016) Pharyngeal Electrical Stimulation in Dysphagia Poststroke: A Prospective, Randomized Single-Blinded Interventional Study. Neurorehabilitation and neural repair 30(9):866-75

RCT

n=36 (18 active treatment)

FU=3 months

Although the direction of observed differences were consistent with PES accelerating swallowing recovery over the first 2 weeks postintervention, suboptimal recruitment prevents definitive conclusions.

Studies with more people or longer follow up included. Included in systematic reviews and meta-analyses.

Wang T, Dong L, Cong X et al. (2021) Comparative efficacy of non-invasive neurostimulation therapies for poststroke dysphagia: A systematic review and meta-analysis. Neurophysiologie clinique = Clinical neurophysiology 51 (6):493-506

Systematic review and meta-analysis

n=2 studies

Non-invasive neurostimulation therapies can effectively promote the recovery of dysphagia after stroke.

More recent systematic reviews included. Included in systematic reviews and meta-analyses.