Effects of Transcutaneous Vagal Nerve Stimulation on Post-Surgical Return to Consciousness, Delirium, and Depression

Northwestern University40 enrolled

Overview

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.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

SINGLE

Enrollment

Conditions

Post Operative Delirium Cognitive Impairment Vagus Nerve Stimulation Depression

Interventions

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: 1. Aged \> 18 years of age 2. Patients undergoing lumbar surgery for degenerative disc disease or spinal stenosis involving two or more levels 3. Montreal Cognitive Assessment (MoCA) score ≥ 18 - accept mild 4. Ability to use a keyboard 5. Able to understand and communicate in English 6. Be able to consent independently 7. Women of child-bearing age must be comfortable confirming a negative pregnancy prior to participating in the study. 8. Must not be involved in any other research intervention study testing neurobehavioral functioning Exclusion Criteria: 1. Age \< 18 years of age 2. History of vagotomy (cutting the vagus nerve) 3. 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 4. MoCA \< 18 5. History of seizure disorder or intracranial hemorrhage 6. Patients with carotid stenosis 7. Patients with aneurysms 8. Other neurological diagnoses or a diagnosis of severe psychiatric disorder (e.g., psychosis) or a reported childhood learning disability 9. Pregnancy, breastfeeding 10. Active addiction history 11. ECG adhesive allergy 12. Severe aphasia, preventing subject from understanding the protocol and giving written consent 13. Patients will be excluded postoperatively if there is neck swelling at the proposed site of left tcVNS.

Outcomes

Primary Outcomes

Aim 1: Primary Endpoint 1: Determine if administering auricular tcVNS enhances the speed of recovery of anesthesia.

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

Time frame: 24 Hours

Aim1:Primary Endpoint 2 : Richmond Agitation Sedation Scale (RASS Score)

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.

Time frame: 1 Hour

Aim 2: Primary Endpoint 1: Post Anesthesia Care Unit Discharge (PACU)

Admission time to the PACU to discharge from PACU in minutes elapsed.

Time frame: 3 Hours

Aim 2: Primary Endpoint 2: Discharge from Hospital

Time from Post Anesthesia Care Unit discharge to discharge from the hospital in days/minutes

Time frame: From PACU discharge (average of two hours post-surgical end time) to study completion (average of two days)

Aim 3: Primary Endpoint 1: Post Anesthesia Care Unit delirium

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

Time frame: From PACU arrival to one hour post-PACU arrival

Aim 3: Primary Endpoint 1a: Post Anesthesia Care Delirium

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

Time frame: 30 Days after discharge

Aim3:Primary Endpoint 1b: PHQ-9

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.

Time frame: 30 days

Secondary Outcomes

Aim 3: Secondary Endpoint 1:EEG Monitoring Data

Continuous EEG monitoring data to be evaluated for patterns associated with delirium (polymorphiic delta waves, generalized slowing quantified as delta range vs alpha range power

Time frame: From pre-surgical EEG placement (i.e. approximately 30 minutes before surgery) through study completion (an average of 2 days)

The Montreal Cognitive Assessment (MoCA) evaluations

The MoCA includes measures of memory recll, visuospatial processing, executive functions, attention, language, abstract reasoning and orientation to time and place. Administered baseline and post operative day 2. 0-30 point scale, 26 and above is normal, 18-25 mild cognitive dysfunction, 10-17 is moderate dysfunction and 0-10 is severe dysfunction.

Time frame: 48 hours

SF-36 Survey

The 36-Item Short Form Survey (SF-36) is a self-reported patient outcome measure that assesses physical and mental health across eight domains, including functioning, pain, and vitality. Score ranges from 0 low to 100 high. The higher the score the better the overall health. Administered at baseline and 30 days after discharge.

Time frame: 30 days

Neuro Qol Cognition Function Short Form

This is a brief self-report tool used to measure perceived difficulties in everyday cognitive tasks. It is a portion of of the Quality of Life in Neurological Disorders (Neuro-QoL). he short form uses T-scores, which standardize results against a reference population (typically the U.S. general population).There are 8 questions. A T-score of 50 represents the average for the reference population. A high score indicates better perceived cognitive function. Completed at baseline and 30 days.

Time frame: 30 Days

Neuro- QOL

Neuro-QoL(Quality of Life in Neurological Disorders) is a measurement system that evaluates and monitors the physical, mental, and social effects experienced by adults who may have neurological conditions. Tested at baseline and 30 days.