The RETRAIN Trial Phase 2

Not Applicable

Recruiting

• Conditions: Ischaemic Stroke

• Registration Number: NCT07197996
• Lead Sponsor: Firstkind Ltd

Brief Summary

Ischaemic strokes, caused by a disruption in the brain's blood supply, are the second leading cause of death and disability in the United Kingdom. This single-center prospective randomised study aims to measure cerebral blood flow and oxygen delivery in patients who have recently suffered an ischaemic stroke and are using either the geko® neuromuscular electrostimulation device or an intermittent pneumatic compression (IPC) device as part of their routine clinical care.

The geko® device stimulates a nerve in the lower leg, inducing muscle contractions that enhance blood circulation. The IPC device applies controlled external pressure through compressed air and a pump, cyclically inflating and deflating chambers in a sleeve worn on the leg. This mimics the action of calf muscles to promote blood flow.

The primary objective of this study is to assess the effect of the geko® and IPC devices on cerebral blood flow in stroke patients, specifically during the hyperacute phase (within 36 hours) following an ischaemic stroke. Both devices will be used as part of standard care for VTE prevention. Cerebral blood flow will be measured using functional near-infrared spectroscopy (fNIRS) and electroencephalography (EEG).

Detailed Description

This study is a randomised trial at a single centre, comparing brain blood flow and activity patterns when two standard treatments for preventing blood clots (VTE) are used following a stroke.

Who Can Take Part?

Patients will be identified for the study as part of their routine hospital care when they arrive at hospital through the emergency department. To take part they must:

1. Be 18 years or older

2. Have had an ischaemic stroke confirmed by a stroke doctor

3. Be within 36 hours of stroke symptom onset

4. Be unable to stand or move around

5. Have had a CT or MRI scan confirming no bleeding in the brain

What Will Happen?

After confirming eligibility and once consent is given, 80 participants will be randomly assigned to one of two groups during the study period:

Group 1 - IPC device Group 2 - geko® device

Both devices are standard treatments for preventing blood clots.

Study Assessments

Brain blood flow will be measured while participants are sitting upright in bed. Each session will include:

5 minutes with the device switched off 5 minutes with the device switched on

These assessments will take place twice a day for two days (a total of 40 minutes) with a pre-assessment preparation (a total of 80 minutes over the two days). Blood pressure, ECG, temperature, and oxygen levels will be continuously monitored. No follow-up is required after the study.

Study Timeline

• Status Verified: 2025-03
• Study Start: 2025-07-01
• Study First Submitted: 2025-09-25
• Study First Submitted QC: 2025-09-25
• Last Update Submitted: 2025-09-25
• Study First Posted: 2025-09-30
• Last Update Posted: 2025-09-30
• Primary Completion: 2026-03-01
• Study Completion: 2026-07-01

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 80

Inclusion Criteria

1. Adult over 18
2. Patient with ischaemic stroke diagnosis confirmed by a stroke physician.
3. Within 36 hours of symptom onset.
4. Unable to stand or mobilise without assistance.
5. No intracerebral haemorrhage as ruled out by computerised tomography (CT) or Magnetic Resonance Imaging (MRI) scan.

Exclusion Criteria

1. Inability to gain consent from the patient, or a declaration from a Personal Consultee or Nominated Consultee.

2. Absence of a transient ischaemic attack (TIA).

3. Clinically apparent deep vein thrombosis at screening

4. Patient is expected to require palliative care within 14 days

5. No response to the geko® device i.e. no involuntary rhythmic upward and outward movement of the foot (dorsiflexion) at the maximum tolerable device setting.

6. Contraindications for the use of the geko™ device

   • Allergy to hydrogel constituents

7. Contraindications to IPC

   • Severe peripheral vascular disease
   • Large leg ulcers requiring extensive bandaging (small ulcers or skin breaks with flat coverings are not an exclusion)
   • Severe oedema
   • Leg deformities making appropriate fitting impossible
   • Symptomatic congestive cardiac failure of NYHA class IV (symptoms of heart failure at rest, any physical activity causing further discomfort).

8. Single or double leg amputations.

9. Participation in any other clinical trial

10. Patients must not have a current coronavirus (COVID-19) infection

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
Change in Cerebral Blood Flow During Device Use	Day 1-2 (within 36 hours of stroke onset; measurements taken twice daily for 2 consecutive days)	Cerebral blood flow (CBF) will be assessed using functional near-infrared spectroscopy (fNIRS) combined with EEG, beat-to-beat blood pressure, and transcutaneous CO₂ monitoring. Measurements will compare baseline (no device) to during active use of either the Intermittent Pneumatic Compression (IPC) device or the geko® T3 device. The primary analysis will evaluate differences in cerebral haemodynamics between the two randomized intervention groups.

Secondary Outcome Measures

Name	Time	Method
Change in Neurovascular Coupling During Device Use	Day 1-2 (twice daily assessments for 2 consecutive days)	Changes in neurovascular coupling will be assessed using combined functional near-infrared spectroscopy (fNIRS) and EEG during resting state and during active use of the Intermittent Pneumatic Compression (IPC) device or the geko® T3 device.
Change in Dynamic Cortical Connectivity During Device Use	Day 1-2 (twice daily assessments for 2 consecutive days)	Functional connectivity between cortical regions will be measured using fNIRS+EEG data during intervention (IPC or geko® device) compared to baseline.
Incidence of Adverse Events	Up to 2 days from enrolment	Number and type of adverse events observed in participants during and after use of either device.
Incidence of Serious Adverse Events	Up to 2 days from enrolment	Frequency of serious adverse events, including death, life-threatening illness, permanent impairment, or prolonged hospitalisation
Incidence of Adverse Device Effects	Up to 2 days from enrolment	Frequency of device-related adverse events such as discomfort, skin irritation, or unexpected physiological responses to device use.
Incidence of Serious Adverse Device Effects	Up to 2 days from enrolment	Frequency of serious device-related adverse events meeting criteria for seriousness under ISO 14155:2020.
Incidence of Device Deficiencies	Up to 2 days from enrolment	Frequency and type of device deficiencies (malfunctions, usability issues, or inadequacy of instructions for use) observed during the trial.

Trial Locations

Locations (1)

Countess of Chester Hospital; 🇬🇧 Chester, Cheshire, United Kingdom