Feasibility and Acceptability of Transcutaneous Vagal Nerve Stimulation in Recovery of Upper Limb Function Post Stroke

This study will find out whether electrical stimulation of a nerve called the "vagus" nerve is acceptable for patients undergoing physiotherapy for arm weakness after a stroke. 20 patients will be recruited if they had a stroke between 4 and 48 months previously and have been left with reduced function in the affected arm. Patients will receive 3 sessions of physiotherapy per week for 6 weeks. Each session will last 1 hour during which the patient will be asked to perform specific movements e.g. shuffling cards, reaching for a shelf. With each arm movement the therapist will turn on a stimulator which is worn clipped to the patients ear. This will deliver a short burst of electricity creating a mild tingling sensation.

At the first visit to the Clinical research Facility, the researcher will check that the patient is still happy to take part. Then, some information about the patient e.g. age, sex, date of stroke, risk factors for stroke will be recorded. Next, the therapist will assess how much existing strength and function the patient has in the arm affected by their stroke using a variety of rating scales. Some brief questionnaires will also be used to measure the patients levels of depression, anxiety, fatigue, quality of life and levels of independence.

These initial assessments will take approximately one hour and will be conducted at the first visit, before the exercises commence. Next the research physiotherapist will clean the patients ear using an alcohol wipe then apply the vagal nerve stimulator clip to part of the ear. The stimulator will be set to deliver a burst of electricity which the patient will feel as a tingling sensation that is not uncomfortable.

The exercise session will then commence with a five minute warmup consisting of whole arm movements using equipment such as pedals and cylinders to facilitate activity. The patient will then be asked to perform a range of practical tasks using their weak arm e.g.turning cards, moving objects of various shapes and sizes, opening and closing bottles and bilateral activities such as lifting objects with both hands. The exercise regime will aim to incorporate 300- 400 such arm movements and will take approximately one hour.

During the exercises, the therapist will press a switch to trigger a run of vagal nerve stimulation in time with the patient's activity. Patients will be videoed during the therapy sessions to allow researchers to retrospectively count the number and type of repetitive movements successfully performed. At the end of the exercises, the stimulator clip will be removed from the patient's ear and cleaned with an alcohol disinfectant wipe ready for next use. After each therapy session, patients will be asked to document on scale of 05 how much they experienced skin reddening, irritation, nausea, dizziness, and headache. Patients will be asked to rate their level of discomfort and fatigue arising from the session using a 05 scale.