Ischaemic StrokeRETRAIN 2NCT07197996
The RETRAIN Trial Phase 2
A study testing Intermittent Pneumatic Compression and geko® T3 in people with Ischaemic Stroke, run by Firstkind Ltd at 1 site in United Kingdom.
Trial 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… Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Ischaemic Stroke
- What is being tested?
- Intermittent Pneumatic Compression and geko® T3
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 53 participants
- Where
- 1 siteUnited Kingdom
- Study dates
- 1 Jul 2025to 26 May 2026
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Adult over 18
- Patient with ischaemic stroke diagnosis confirmed by a stroke physician.
- Within 36 hours of symptom onset.
- Unable to stand or mobilise without assistance.
- No intracerebral haemorrhage as ruled out by computerised tomography (CT) or Magnetic Resonance Imaging (MRI) scan.
Who cannot join
- Inability to gain consent from the patient, or a declaration from a Personal Consultee or Nominated Consultee.
- Absence of a transient ischaemic attack (TIA).
- Clinically apparent deep vein thrombosis at screening
- Patient is expected to require palliative care within 14 days
- 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.
- Contraindications for the use of the geko™ device
Show all 16Show fewer
- Allergy to hydrogel constituents
- 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).
- Single or double leg amputations.
- Participation in any other clinical trial
- Patients must not have a current coronavirus (COVID-19) infection
Trial locations and contacts
1 site in 1 country.
United Kingdom1 site
Countess of Chester Hospital
Chester, Cheshire, CH2 1UL
About this study
Official title: MonitoRing the Effect of Intermittent Pneumatic Compression and TRAnscutaneous Functional electrIcal Stimulation of the Common Peroneal Nerve Using the Geko® Device on Cerebral Haemodynamics in Patients With Ischaemic Strokes (The RETRAIN Trial Phase 2)
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).
Read the 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:
- Be 18 years or older
- Have had an ischaemic stroke confirmed by a stroke doctor
- Be within 36 hours of stroke symptom onset
- Be unable to stand or move around
- 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.
- Conditions
- Ischaemic Stroke
- Being tested
- Intermittent Pneumatic Compression, geko® T3
- Keywords
- Acute ischemic stroke, Neuromuscular electrostimulation, Effects on cerebral blood flow, Randomised controlled trial, Cerebral blood flow measurements, Stroke rehabilitation
- Medical subject headings
- Ischemic Stroke
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Intermittent Pneumatic CompressionDevice
Also called Kendall SCD™ 700 Sequential Compression System
The IPC arm will use the Kendall SCD™ 700 Sequential Compression System, a routinely employed device for VTE prophylaxis in stroke patients. In this study, IPC sleeves will be applied bilaterally to the legs within 36 hours of stroke onset and operated according to the manufacturer's instructions. The intervention is distinguished by its cyclical external leg compression to enhance venous return, and it serves as the comparator to the geko® device for evaluating effects on cerebral blood flow and haemodynamics.
geko® T3Device
Also called geko® device, neuromuscular electrostimulation
The geko® T3 device is a small, disposable, battery-powered neuromuscular electrostimulation device manufactured by Firstkind Ltd. In this study, the geko® will be applied bilaterally to the common peroneal nerve at the knee within 36 hours of stroke onset. It delivers transcutaneous electrical stimulation at 1 Hz, producing involuntary rhythmic foot dorsiflexion to activate the calf and foot muscle pumps. The intervention is distinguished from IPC by its mechanism of action (neuromuscular stimulation vs. external compression) and will be evaluated for its impact on cerebral haemodynamics, neurovascular coupling, and dynamic cerebral autoregulation during VTE prophylaxis.
| Study group | Role | What they receive |
|---|---|---|
| Group 1 - IPC device | Experimental | IPC sleeves applied bilaterally according to manufacturer's instructions for standard VTE prophylaxis following ischaemic stroke. Receives: Device: Intermittent Pneumatic Compression |
| Group 2 - geko® device | Experimental | The geko® device is a disposable, battery-powered neuromuscular electrostimulation device applied bilaterally to the peroneal nerve at the knee. It delivers low-frequency stimulation to activate the calf and foot muscle pumps, enhancing venous return and microcirculatory blood flow. Devices will be applied according to the manufacturer's instructions for VTE prophylaxis. Receives: Device: geko® T3 |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in Cerebral Blood Flow During Device Use
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.
Measured: Day 1-2 (within 36 hours of stroke onset; measurements taken twice daily for 2 consecutive days)
Secondary outcomes (7)
Change in Neurovascular Coupling During Device Use
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.
Measured: Day 1-2 (twice daily assessments for 2 consecutive days)
Change in Dynamic Cortical Connectivity During Device Use
Functional connectivity between cortical regions will be measured using fNIRS+EEG data during intervention (IPC or geko® device) compared to baseline.
Measured: Day 1-2 (twice daily assessments for 2 consecutive days)
Incidence of Adverse Events
Number and type of adverse events observed in participants during and after use of either device.
Measured: Up to 2 days from enrolment
Incidence of Serious Adverse Events
Frequency of serious adverse events, including death, life-threatening illness, permanent impairment, or prolonged hospitalisation
Measured: Up to 2 days from enrolment
Incidence of Adverse Device Effects
Frequency of device-related adverse events such as discomfort, skin irritation, or unexpected physiological responses to device use.
Measured: Up to 2 days from enrolment
Incidence of Serious Adverse Device Effects
Frequency of serious device-related adverse events meeting criteria for seriousness under ISO 14155:2020.
Measured: Up to 2 days from enrolment
Incidence of Device Deficiencies
Frequency and type of device deficiencies (malfunctions, usability issues, or inadequacy of instructions for use) observed during the trial.
Measured: Up to 2 days from enrolment
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted30 Sep 2025
- Study start1 Jul 2025
- Primary completion26 May 2026
- Study completion26 May 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Ischaemic StrokeStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Randomized, Parallel Assignment
- Masking
- None (open label)
- Enrolment
- 53 participants (actual)
Sponsor and investigators
- Lead sponsor
- Firstkind Ltd
- Sponsor type
- Industry (pharma, biotech, devices)
- Collaborators
- Innovate UK
- Responsible party
- Sponsor
- Investigators
- Kausik Chatterjee, Study director, COUNTESS OF CHESTER HOSPITAL NHS FOUNDATION TRUST
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07197996
- Sponsor's protocol ID
- ISS-BBF-002
- Other IDs
- 10038715
- Acronym
- RETRAIN 2
- Status last verified
- Sep 2026
- First submitted
- 25 Sep 2025
- Last updated
- 15 Sep 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: De-identified individual participant data (IPD) underlying the results of this trial (including baseline characteristics, outcome measures, and safety data) will be made available to other researchers upon reasonable request, following publication of the main trial results. Data will be shared through a controlled access process after approval of a research proposal and data sharing agreement. Supporting documents (such as the study protocol and statistical analysis plan) will also be available.
Study at a glance
From the registry record, last updated by the sponsor on 15 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- MonitoRing the Effect of Intermittent Pneumatic Compression and TRAnscutaneous Functional electrIcal Stimulation of the Common Peroneal Nerve Using the Geko® Device on Cerebral Haemodynamics in Patients With Ischaemic Strokes (The RETRAIN Trial Phase 2)
- ClinicalTrials.gov ID
- NCT07197996
- Acronym / sponsor ID
- RETRAIN 2 / ISS-BBF-002
- Conditions
- Ischaemic Stroke
- Keywords
- Acute ischemic stroke, Neuromuscular electrostimulation, Effects on cerebral blood flow, Randomised controlled trial, Cerebral blood flow measurements, Stroke rehabilitation
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 53 participants (actual)
- Lead sponsor
- Firstkind LtdIndustry (pharma, biotech, devices)
- Collaborators
- Innovate UK
- Study start
- 1 Jul 2025 (actual)
- Primary completion
- 26 May 2026 (actual)
- Study completion
- 26 May 2026 (actual)
- First posted
- 30 Sep 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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:
- Be 18 years or older
- Have had an ischaemic stroke confirmed by a stroke doctor
- Be within 36 hours of stroke symptom onset
- Be unable to stand or move around
- 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 design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- Randomized, Parallel Assignment
| Arm | Type | Receives |
|---|---|---|
| Group 1 - IPC device | Experimental | Device: Intermittent Pneumatic CompressionIPC sleeves applied bilaterally according to manufacturer's instructions for standard VTE prophylaxis following ischaemic stroke. |
| Group 2 - geko® device | Experimental | Device: geko® T3The geko® device is a disposable, battery-powered neuromuscular electrostimulation device applied bilaterally to the peroneal nerve at the knee. It delivers low-frequency stimulation to activate the calf and foot muscle pumps, enhancing venous return and microcirculatory blood flow. Devices will be applied according to the manufacturer's instructions for VTE prophylaxis. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- Adult over 18
- Patient with ischaemic stroke diagnosis confirmed by a stroke physician.
- Within 36 hours of symptom onset.
- Unable to stand or mobilise without assistance.
- No intracerebral haemorrhage as ruled out by computerised tomography (CT) or Magnetic Resonance Imaging (MRI) scan.
Key exclusion criteria (16 listed)
- Inability to gain consent from the patient, or a declaration from a Personal Consultee or Nominated Consultee.
- Absence of a transient ischaemic attack (TIA).
- Clinically apparent deep vein thrombosis at screening
- Patient is expected to require palliative care within 14 days
- 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.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Intermittent Pneumatic CompressionAlso: Kendall SCD™ 700 Sequential Compression SystemThe IPC arm will use the Kendall SCD™ 700 Sequential Compression System, a routinely employed device for VTE prophylaxis in stroke patients. In this study, IPC sleeves will be applied bilaterally to the legs within 36 hours of stroke onset and operated according to the manufacturer's instructions. The intervention is distinguished by its cyclical external leg compression to enhance venous return, and it serves as the comparator to the geko® device for evaluating effects on cerebral blood flow and haemodynamics. | Device | Group 1 - IPC device |
| geko® T3Also: geko® device, neuromuscular electrostimulationThe geko® T3 device is a small, disposable, battery-powered neuromuscular electrostimulation device manufactured by Firstkind Ltd. In this study, the geko® will be applied bilaterally to the common peroneal nerve at the knee within 36 hours of stroke onset. It delivers transcutaneous electrical stimulation at 1 Hz, producing involuntary rhythmic foot dorsiflexion to activate the calf and foot muscle pumps. The intervention is distinguished from IPC by its mechanism of action (neuromuscular stimulation vs. external compression) and will be evaluated for its impact on cerebral haemodynamics, neurovascular coupling, and dynamic cerebral autoregulation during VTE prophylaxis. | Device | Group 2 - geko® device |
Primary outcome
Change in Cerebral Blood Flow During Device Use
Time frame: 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.
7 secondary outcomes
Change in Neurovascular Coupling During Device Use
Time frame: Day 1-2 (twice daily assessments for 2 consecutive days)
Change in Dynamic Cortical Connectivity During Device Use
Time frame: Day 1-2 (twice daily assessments for 2 consecutive days)
Incidence of Adverse Events
Time frame: Up to 2 days from enrolment
Incidence of Serious Adverse Events
Time frame: Up to 2 days from enrolment
Incidence of Adverse Device Effects
Time frame: Up to 2 days from enrolment
Incidence of Serious Adverse Device Effects
Time frame: Up to 2 days from enrolment
Incidence of Device Deficiencies
Time frame: Up to 2 days from enrolment
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 15 Sep 2026.
- Individual participant dataSharing planned: Yes. De-identified individual participant data (IPD) underlying the results of this trial (including baseline characteristics, outcome measures, and safety data) will be made available to other researchers upon reasonable request, following publication of the main trial results. Data will be shared through a controlled access process after approval of a research proposal and data sharing agreement. Supporting documents (such as the study protocol and statistical analysis plan) will also be available.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Kausik Chatterjee study director
COUNTESS OF CHESTER HOSPITAL NHS FOUNDATION TRUST
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Intermittent Pneumatic Compression and geko® T3 in people with Ischaemic Stroke, run by Firstkind Ltd at 1 site in United Kingdom.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 16 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 15 Sep 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United Kingdom. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in Cerebral Blood Flow During Device Use (time frame: Day 1-2 (within 36 hours of stroke onset; measurements taken twice daily for 2 consecutive days)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 15 Sep 2026.