Early Electrical Stimulation to Prevent Complications in the Arm Post-stroke - a Feasibility Study

Overview

Stroke is the largest cause of adult disability in the United Kingdom. Loss of hand function, muscle weakness, pain, and joint deformities are persistent and disabling problems for nearly half of all stroke survivors. This can, in part, result from patients not getting adequate therapy targeting the hand and arm in the very early stages of rehabilitation. Previous research has highlighted the importance of early rehabilitation interventions after stroke. Although in stroke patients the damage is to the brain rather than the limbs, muscle wastage (atrophy) can occur soon after stroke through non-use. Muscle atrophy can even occur in those who have retained some degree of active arm movement. Electrical stimulation (ES) is a painless treatment in which small pulses of electrical current from a battery operated portable device are used to activate a paralysed muscle and produce a strong muscle contraction. ES has been shown to increase brain activity and can hence influence the formation of new nerve pathways (known as neuroplasticity) to replace those damaged by stroke. Previous studies have concluded that six weeks of ES to the muscle on the back of the forearm improved the chance of a person recovering arm function. However, as the intensity of treatment was not sufficient to prevent the complications identified in this proposal, the impact of any functional benefit was significantly limited. We plan to build on previous research by training clinical therapists to operate ES devices; starting ES much earlier after stroke; applying a higher intensity treatment to more of the forearm muscles (i.e. both the front and back of the forearm) and providing treatment for a longer period of time than previously carried out. We will evaluate the feasibility of incorporating ES into a patient self-management programme to enable independent use outside of routine therapist led rehabilitation sessions.

The study will evaluate the feasibility of running a randomised controlled trial that will test the efficacy of delivering early, intensive electrical stimulation (ES) to the wrist flexors and wrist extensors to prevent post stroke complications (such as pain and muscle contractures) to the paretic upper limb after stroke. The feasibility study will involve a single centre feasibility randomised controlled trial and an integrated qualitative study (patient and carer interviews and therapist focus discussion groups). Participants in the intervention group will receive electrical stimulation (ES) therapy. ES is similar to a TENS machine and delivers a constant stimulating current from 0 to 100 mA via two independent channels. The motor points for stimulation are already known. The therapist will identify the motor points for the forearm flexors (this will lead to a flexion movement of both the wrist and fingers) and the extensors (this will lead to an extensor of wrist and fingers), and will place an electrode on these motor points using sticky pads. They will then connect the electrodes to the respective channels in the electrical stimulator. The ES will be set to deliver a 450μs pulse at a frequency of 40-60Hz (as per patient convenience). The intensity of the current will be increased to produce an alternating contraction of the flexors and extensors using a flex-hold-extend-hold pattern. A single stimulation and hold cycle will last 20 seconds and this will be cyclically repeated for 30 minutes after which the device can be removed. The devices required for this study have been donated by Verity Medical Ltd. The devices are CE marked and will be used in accordance with the manufacturer's marketing authorisation. Band 5 or above therapists will administer the initial ES treatment and mark the correct electrode placement. The initial treatment will take between 15 and 20 minutes to assess the correct motor points. This is done by ensuring that a pure flexion or extension movement is produced with no ulnar or radial deviation. Once the motor points have been marked on the skin (using medical skin marker pens) any member of the therapy team band 3 or above can provide subsequent treatments which takes between 2-5 minutes to apply the electrode pads to the pre-marked motor points and switch on the device to the pre-stored treatment setting. The ES device will then provide treatment for 30 minutes, without the need for a therapist to remain present. It will be removed once the device has completed the set programme and switched itself off. Patients and/or their carers will be shown by a therapist how to apply the electrode pads and use the device in under 10 minutes. Patients and/or their carers will be asked to self-manage the treatment upon discharge so that treatment can continue twice a day, 5 days a week, for a total period of 3 months. A patient diary will be included in the device case and participants and/or their nominated carer will be encouraged to record the times that the device is used. Participants in the control group will not receive the electrical stimulation therapy intervention but will have access to all other usual services. Ten pairs of patient participants and their nominated carers will be interviewed about their experience of using or supporting a loved one to use electrical stimulation therapy as part of a research study. The interviews will be used to examine issues regarding compliance with the ES treatment regime, acceptability of the ES treatment, experience of supporting a stroke survivor in using the ES treatment, any perceived treatment effects, the training that was provided and the ongoing support needs and any issues related to recruitment and consent. The purpose of these interviews is to identify issues related to delivering ES as part of a randomised controlled trial. The findings from these interviews will contribute to the final content and design of the research protocol for the definitive trial. Each interview will last for around one hour in total and will take place in the participants' homes, or clinic if preferred, and will be recorded, transcribed verbatim and analysed thematically. Interviews will be conducted following completion of the 3 month follow-up assessments. Five pairs of patient participants from the control group and their nominated carers will be interviewed to examine any issues from the perspective of the control group participants. Four Physiotherapists and four occupational therapists from the Nottingham Stroke Unit will be invited to participate in a minimum of one and a maximum of three focus discussion groups during the course of the feasibility RCT. The focus groups will discuss the barriers and facilitators to successfully implementing the intervention and study protocol into clinical practice.