AnesthesiaNCT07191340
Noninvasive Transcutaneous Vagal Nerve Stimulation (tcVNS) for Neuromodulating the Conscious State
A study testing Vagus nerve stimulator in people with Anesthesia and Delirium, run by Northwestern University.
Trial summary
The purpose of this study is to examine whether noninvasive, transcutaneous vagal nerve stimulation (tcVNS) (Gammacore Sapphire Device) can help restore consciousness in patients in the Operating Room and Post Anesthesia Care Unit (PACU). Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Anesthesia, Delirium, Depression
- What is being tested?
- Vagus nerve stimulator
- Type of treatment
- Medical device
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 0 participants
- Where
- No sites listed yet
- Study dates
- Oct 2023to Nov 2023
- 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
- Aged > 18 years of age
- Patients undergoing lumbar surgery for degenerative disc disease or spinal stenosis involving two or more levels
- Mini-Mental State Examination (MMSE) score ≥ 15-accept mild
- Ability to use a keyboard
- Able to understand and communicate in English
- Be able to consent independently
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- Women of child-bearing age must be comfortable confirming a negative pregnancy prior to participating in the study.
- Must not be involved in any other research intervention study testing neurobehavioral functioning
- Good internet connectivity and ability to use computer, smart phone or good telephone connectivity (follow up)
Who cannot join
- Age < 18 years of age
- History of vagotomy (cutting the vagus nerve)
- History of bradycardia, heart block, prolonged QT syndrome, brugada syndrome, heart failure with ejection fraction less than 35% and/or New York Heart Association symptoms
- MMSE < 15
- History of seizure disorder or intracranial hemorrhage
- Patients with carotid stenosis
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- Patients with aneurysms
- Other neurological diagnoses or a diagnosis of severe psychiatric disorder (e.g., psychosis) or a reported childhood learning disability
- Pregnancy, breastfeeding
- Active addiction history
- ECG adhesive allergy
- Severe aphasia, preventing subject from understanding the protocol and giving written consent
- Patients with an active implantable medical device, such as a pacemaker, hearing aid implant, or any implanted electronic device
- Patients with metallic device such as a stent, bone plate or bone screw implanted at or near their neck
- Patients with an active implantable medical device, such as a pacemaker, hearing aid implant, or any implanted electronic device
- Patients with metallic device such as a stent, bone plate or bone screw implanted at or near their neck
- Patients who are using another device at the same time (e.g., transcutaneous electrical nerve stimulation (TENS) Unit, muscle stimulator) or any portable electronic device (e.g., mobile phone).
About this study
Official title: A Prospective, Randomized, Single-Blinded, Crossover Clinical Trial Evaluating the Use of Noninvasive Transcutaneous Vagal Nerve Stimulation (tcVNS) for Neuromodulating the Conscious State
The purpose of this study is to examine whether noninvasive, transcutaneous vagal nerve stimulation (tcVNS) (Gammacore Sapphire Device) can help restore consciousness in patients in the Operating Room and Post Anesthesia Care Unit (PACU). To examine whether tcVNS administered in the PACU can help reduce delirium and depression post-surgery, speeding up cognitive recovery from anesthesia, and finally determine if tcVNS can expedite discharge from the PACU.
- Conditions
- Anesthesia, Delirium, Depression, Cognitive Function
- Being tested
- Vagus nerve stimulator, Placebo comparator sham
- Keywords
- Vagal Nerve Stimulator, Post Anesthesia Care, Post Surgical
- Medical subject headings
- Delirium, Depression
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Vagus nerve stimulatorDevice
Vagus nerve stimulator placed on neck and activated
Placebo comparator shamDevice
Vagus nerve stimulator placed on neck and not activated
| Study group | Role | What they receive |
|---|---|---|
| Treatment Group Stimulation of Vagus Nerve | Active comparator | Stimulation of the vagus nerve with nerve stimulator placed on neck Receives: Device: Vagus nerve stimulator |
| Sham Placebo Group No Stimulation to Vagus Nerve | Placebo comparator | Nerve stimulator placed on neck but not activated. Receives: Device: Placebo comparator sham |
What is being measured
The primary outcome is the main question the study is designed to answer.
Aim 1: To determine if administering tcVNS enhances recovery from anesthesia
Time to a Patient State Index™ (PSi, Sedline Sedation Monitor, Massimo, Inc, Irvine, CA) score of 85.The PSi is a quantitative score derived from 4 channel EEG monitoring of the frontal and prefrontal cortex for assessing level of consciousness during sedation and general anesthesia. The score ranges from 0 (EEG suppression) to 100 (fully awake). A PSi range of 25-50 indicates optimal hypnotic state for general anesthesia.
Measured: 60 minutes
To determine if administering tcVNS improves Richmond Agitation-Sedation Scale (RASS) scores after anesthesia
RASS Score on arrival to the PACU then 10, 15, 30, 45 and 60 min later.The Richmond Agitation-Sedation Scale (RASS) is a standardized instrument to assess arousal, cognition, and sustainability to stepped progression of stimuli. The patient is first observed. If alert a score between 1 to 4 is assigned based on their cognitive state. If the patient is not alert, the patient's name is loudly spoken and they are instructed to open their eyes and look at the speaker. This is repeated once if necessary. If there is eye opening and eye contact for > 10 seconds, a score of -1 is assigned. If not sustained for 10 secs then a score of -2 is assigned, and so forth.
Measured: 60 minutes
Secondary outcomes (1)
To determine if tcVNS can improve conscious cognitive control in post-surgical patients.
Targeted tcVNS compared to sham tcVNS will reduce PACU and hospital ward delirium and post-surgical depression. The investigators will test this hypothesis by PACU and in-hospital evaluations for delirium and in-hospital measurement of depression prior to discharge and at a one-month virtual follow-up evaluation.
Measured: 1 month after surgery
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted24 Sep 2025
- Study startOct 2023 (estimated)
- Primary completionOct 2023 (estimated)
- Study completionNov 2023 (estimated)
Why it stopped: Withdrew study equipment issue.
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for AnesthesiaStudies of the same condition, open and under way.
- More trials run by Northwestern UniversityThe sponsor's other registered studies.
- 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 controlled trial
- Masking
- Double blind
- Who is masked
- Participant, Outcomes assessor
- Enrolment
- 0 participants (actual)
Sponsor and investigators
- Lead sponsor
- Northwestern University
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Alyson Engle, MD, Principal investigator, Northwestern Univesity
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07191340
- Sponsor's protocol ID
- STU00217188
- Status last verified
- Sep 2025
- First submitted
- 22 Mar 2024
- Last updated
- 24 Sep 2025
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- Yes
Study at a glance
From the registry record, last updated by the sponsor on 24 Sep 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Prospective, Randomized, Single-Blinded, Crossover Clinical Trial Evaluating the Use of Noninvasive Transcutaneous Vagal Nerve Stimulation (tcVNS) for Neuromodulating the Conscious State
- ClinicalTrials.gov ID
- NCT07191340
- Acronym / sponsor ID
- STU00217188
- Conditions
- Anesthesia, Delirium, Depression, Cognitive Function
- Keywords
- Vagal Nerve Stimulator, Post Anesthesia Care, Post Surgical
- Study type
- Interventional
- Recruitment status
- WithdrawnReason stopped: Withdrew study equipment issue.
- Enrolment
- 0 participants (actual)
- Lead sponsor
- Northwestern UniversityUniversity, hospital or other
- Study start
- Oct 2023 (estimated)
- Primary completion
- Oct 2023 (estimated)
- Study completion
- Nov 2023 (estimated)
- First posted
- 24 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.
The purpose of this study is to examine whether noninvasive, transcutaneous vagal nerve stimulation (tcVNS) (Gammacore Sapphire Device) can help restore consciousness in patients in the Operating Room and Post Anesthesia Care Unit (PACU). To examine whether tcVNS administered in the PACU can help reduce delirium and depression post-surgery, speeding up cognitive recovery from anesthesia, and finally determine if tcVNS can expedite discharge from the PACU.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (participant, outcomes assessor)
- Number of arms
- 2
- Model description
- Randomized controlled trial
| Arm | Type | Receives |
|---|---|---|
| Treatment Group Stimulation of Vagus Nerve | Active comparator | Device: Vagus nerve stimulatorStimulation of the vagus nerve with nerve stimulator placed on neck |
| Sham Placebo Group No Stimulation to Vagus Nerve | Placebo comparator | Device: Placebo comparator shamNerve stimulator placed on neck but not activated. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (9 listed)
- Aged > 18 years of age
- Patients undergoing lumbar surgery for degenerative disc disease or spinal stenosis involving two or more levels
- Mini-Mental State Examination (MMSE) score ≥ 15-accept mild
- Ability to use a keyboard
- Able to understand and communicate in English
Key exclusion criteria (17 listed)
- Age < 18 years of age
- History of vagotomy (cutting the vagus nerve)
- History of bradycardia, heart block, prolonged QT syndrome, brugada syndrome, heart failure with ejection fraction less than 35% and/or New York Heart Association symptoms
- MMSE < 15
- History of seizure disorder or intracranial hemorrhage
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 |
|---|---|---|
| Vagus nerve stimulatorVagus nerve stimulator placed on neck and activated | Device | Treatment Group Stimulation of Vagus Nerve |
| Placebo comparator shamVagus nerve stimulator placed on neck and not activated | Device | Sham Placebo Group No Stimulation to Vagus Nerve |
Primary outcome
Aim 1: To determine if administering tcVNS enhances recovery from anesthesia
Time frame: 60 minutes
Time to a Patient State Index™ (PSi, Sedline Sedation Monitor, Massimo, Inc, Irvine, CA) score of 85.The PSi is a quantitative score derived from 4 channel EEG monitoring of the frontal and prefrontal cortex for assessing level of consciousness during sedation and general anesthesia. The score ranges from 0 (EEG suppression) to 100 (fully awake). A PSi range of 25-50 indicates optimal hypnotic state for general anesthesia.
To determine if administering tcVNS improves Richmond Agitation-Sedation Scale (RASS) scores after anesthesia
Time frame: 60 minutes
RASS Score on arrival to the PACU then 10, 15, 30, 45 and 60 min later.The Richmond Agitation-Sedation Scale (RASS) is a standardized instrument to assess arousal, cognition, and sustainability to stepped progression of stimuli. The patient is first observed. If alert a score between 1 to 4 is assigned based on their cognitive state. If the patient is not alert, the patient's name is loudly spoken and they are instructed to open their eyes and look at the speaker. This is repeated once if necessary. If there is eye opening and eye contact for > 10 seconds, a score of -1 is assigned. If not sustained for 10 secs then a score of -2 is assigned, and so forth.
1 secondary outcome
To determine if tcVNS can improve conscious cognitive control in post-surgical patients.
Time frame: 1 month after surgery
Results and safety
The study was withdrawn before enrolling participants, so there are no results.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 24 Sep 2025.
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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.
Alyson Engle, MD principal investigator
Northwestern Univesity
Questions about this trial
What is this clinical trial studying?
A study testing Vagus nerve stimulator in people with Anesthesia and Delirium, run by Northwestern University.
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 9 inclusion and 17 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: withdrawn, as of the sponsor's last update on 24 Sep 2025. Status can change between updates, so confirm with the study contact before making plans.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. 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 was withdrawn before enrolling participants, so there are no results.
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?
Aim 1: To determine if administering tcVNS enhances recovery from anesthesia (time frame: 60 minutes). The study lists 2 primary outcomes in all. 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 24 Sep 2025; AzTrials last refreshed its copy on 8 Nov 2026.