NCT07610655 · Northwestern University
Effects of Transcutaneous Vagal Nerve Stimulation on Post-Surgical Return to Consciousness, Delirium, and Depression
(tVNS)
What this study is about
This study will examine whether noninvasive, transcutaneous vagal nerve stimulation (tcVNS) can help restore consciousness in patients in the operating room and the Post Anesthesia Care Unit (PACU). The study will also investigate if tcVNS can expedite discharge from the PACU and examine whether tcVNS administerd in the PACU helps reduce delirium and depression after surgery.
View original scientific description
This study will examine whether noninvasive, transcutaneous vagal nerve stimulation (tcVNS) can help restore consciousness in patients in the operating room and the Post Anesthesia Care Unit (PACU). The study will also investigate if tcVNS can expedite discharge from the PACU and examine whether tcVNS administerd in the PACU helps reduce delirium and depression after surgery. The study will also evaluate whether tcVNS speeds cognitive recovery from emergence of anesthesia and surgery.
Interventions
DEVICE
Transcutaneous vagal nerve stimulation
The tcVNS device utilized in this study is not an implanted device, but rather is solely operated outside of the body by affixing it around the patient's ear. The device delivers stimulation of the vagus nerve at designated intensity, interval, and frequency.
DEVICE
Sham (No Treatment)
The stimulator is flipped upside down so that the participant does not receive stimulation of the vagal nerve.
Primary outcome measures
Aim 1: Primary Endpoint 1: Determine if administering auricular tcVNS enhances the speed of recovery of anesthesia.
Time frame: 24 Hours
Time in minutes to a Patient State Index (PSI) (Sedline Sedation Monitor) 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 consciousnes during sedation and general anesthesia. The score ranges from 0 (EEG supression) -100 (fully awake). A PSI range of 25-50 indicates optimal hypnotic state for general anesthesia
Aim1:Primary Endpoint 2 : Richmond Agitation Sedation Scale (RASS Score)
Time frame: 1 Hour
The Richmond Agitation-Sedation Scale (RASS) is a 10-point validated scale used to measure patient sedation levels in post-anesthesia care unit, ranging from +4 (combative) to -5 (unarousable). A score of 0 is "alert and calm".Measured on arrival to PACU then at 10,15,30,45,60 minutes after admission to PACU.
Aim 2: Primary Endpoint 1: Post Anesthesia Care Unit Discharge (PACU)
Time frame: 3 Hours
Admission time to the PACU to discharge from PACU in minutes elapsed.
Aim 2: Primary Endpoint 2: Discharge from Hospital
Time frame: From PACU discharge (average of two hours post-surgical end time) to study completion (average of two days)
Time from Post Anesthesia Care Unit discharge to discharge from the hospital in days/minutes
Aim 3: Primary Endpoint 1: Post Anesthesia Care Unit delirium
Time frame: From PACU arrival to one hour post-PACU arrival
Comparison between active and sham tcVNS on delirium scores in the PACU at 30, 45 and 60 minutes after admission to the PACU. The 3D Confusion Assessment Method (3D CAM) will be administered at 30, 45 and 60 minutes after admission to PACU. The 3D CAM diagnostic tool scores delirium based on four core features, where Feature 1 (Acute Change) AND Feature 2 (Inattention) MUST be present, plus either Feature 3 (Disorganized Thinking) or Feature 4 (Altered Consciousness). It offers a severity score (3D-CAM-S) ranging from 0-20, with higher scores indicating more severe symptoms (0/20 low 20/20 high
Aim 3: Primary Endpoint 1a: Post Anesthesia Care Delirium
Time frame: 30 Days after discharge
Delirium scores 30 days after discharge from the hospital. The 3D Confusion Assessment Method (3D CAM) will be administered 30 days after discharge from the hospital. The 3D CAM diagnostic tool scores delirium based on four core features, where Feature 1 (Acute Change) AND Feature 2 (Inattention) MUST be present, plus either Feature 3 (Disorganized Thinking) or Feature 4 (Altered Consciousness). It offers a severity score (3D-CAM-S) ranging from 0-20, with higher scores indicating more severe symptoms (0/20 low 20/20 high
Aim3:Primary Endpoint 1b: PHQ-9
Time frame: 30 days
The Patient Health Questionnaire Nine (PHQ-9) is a 9-question survey used to measure patient depression potential, ranging 1-27 (1 low possibility of depression to 27 highest potential for depression. Tested at baseline, post operative day 1 and 30 days post discharge from hospital.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Aged \> 18 years of age
- Patients undergoing lumbar surgery for degenerative disc disease or spinal stenosis involving two or more levels
- Montreal Cognitive Assessment (MoCA) score ≥ 18 - accept mild
- Ability to use a keyboard
- Able to understand and communicate in English
- Be able to consent independently
- 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
Exclusion criteria
- 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
- History of seizure disorder or intracranial hemorrhage
- Patients with carotid stenosis
- 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 will be excluded postoperatively if there is neck swelling at the proposed site of left tcVNS.
Where
- Chicago, Illinois
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced May 28, 2026 · Source of record for eligibility and locations