The Passy Muir Swallowing Self Training Device to Enhance Recovery Post Stroke "PMSST"


Phase N/A Results N/A

Trial Description

The purpose of this study is to develop a vibratory self-trainer for the treatment of dysphagia post-stroke.
The aim is to identify the optimal stimulation characteristics for use with participants with swallowing problems including:
- Frequency of vibration
- Mode of vibration either continuous or pulsed
- Pressure of device against the neck
- Duration of vibration to allow a participant to initiate a swallow

Detailed Description

This study investigates the use of self-training device to improve swallowing post-stroke. The device has motors placed on the neck over each side of the thyroid cartilage and provides noninvasive vibratory stimulation. The vibration penetrates through the neck to the tissues in the larynx to activate mechanoreceptors innervated by the internal branch of the superior laryngeal nerve, which when stimulated will trigger swallowing at the brain stem level. The outcomes of this research will be used to develop a device for use by the patients for daily swallowing self-training in their own environment.
Site monitoring and auditing will be conducted at crucial time points during the study, including just prior to participant enrollment. Auditing will be conducted by Julie Kobak, Vice President for Clinical Education of Passy Muir , Inc.
Source data verification will be comparing raw data forms to electronic case report forms.
Standard operating procedures are in place for participant recruitment, data collection, data management, data analysis, and reporting adverse events.
Sample size assessment: Based on previous studies in healthy volunteers contrasting air puff stimulation on the rate of swallowing (1, 2) the expected change in rate of swallowing will be from 1.2 swallows/minute without stimulation to 2.0 swallows/minute with stimulation with a standard deviation of the differences being 0.9. Using a Bonferroni corrected alpha of 0.025 (to test 2 measures) at 0.80 power with an effect size of 0.88, the number of participants needed will be 15 per experiment. Allowing for some participants to participate in several studies, the investigators plan to recruit between 30 and 40 participants with risk of aspiration post stroke.
Potential problems and alternative strategies: Anticipated problems include difficulties with recruiting an adequate sample. There are 3 rooms available for participant testing at Rockingham Memorial Hospital to support multiple participants being tested simultaneously. Furthermore, all the equipment is portable including Powerlab, a laptop, the amplifier system, the Kistler accelerometers, and Inductive plethysmography so participants can be tested in rehabilitation settings and/or in their own home. Advertisements and a website have also been created.



  • Passy Muir Swallowing Self-Trainer Device
    Other Names: PMSST; Swallowing Self-Trainer
    Intervention Desc: Comparison of the effects of different vibratory characteristics on the frequency of swallowing, time of initiation of swallowing with stimulation and urge to swallow. Will compare frequency of vibration, mode of vibration, pressure of device against neck, and duration of vibration. Each session will last no more than 1 hour with short breaks. Each participant can volunteer for up to three nonconsecutive sessions.
    ARM 1: Kind: Experimental
    Label: Participants with swallowing deficits post stroke

Trial Design

  • Observation: Cohort
  • Perspective: Prospective
  • Sampling: Non-Probability Sample

Trial Population

Participants who have swallowing problems secondary to a stroke..


Type Measure Time Frame Safety Issue
Primary Frequency of swallowing During intervention No
Secondary Perceived urge to swallow During intervention No