Enhancing the Effect of Stellate Ganglion Block in the Treatment of Posttraumatic Stress Disorder: A Double-blind Randomized Controlled Trial of Bupivacaine vs Bupivacaine + Ketamine

November 3, 2026 updated by: Rebecca Gomez, MD, The Royal's Institute of Mental Health Research

The goal of this clinical trial is to learn whether stellate ganglion block (SGB), with or without ketamine, can reduce symptoms of post-traumatic stress disorder (PTSD) in adults receiving care through the Operational Stress Injury (OSI) Clinic and military community partners. The main questions it aims to answer are:

Does adding ketamine to the standard SGB anesthetic (bupivacaine) improve treatment effectiveness compared with bupivacaine alone?

Does SGB reduce PTSD symptom severity compared with no injection (control group)?

Researchers will compare participants receiving SGB with bupivacaine, SGB with bupivacaine plus ketamine, and no injection (control) to determine whether SGB reduces PTSD symptoms and whether ketamine enhances the effects of the procedure.

Participants will:

Be randomly assigned to receive SGB with bupivacaine, SGB with bupivacaine plus ketamine, or no injection during the randomized controlled trial portion of the study.

Complete questionnaires and clinical interviews assessing PTSD symptoms, anxiety, depression, functioning, and quality of life.

Participate in follow-up interviews to discuss their experiences with the treatment.

Invite a family member or support person to complete a questionnaire about observed changes in symptoms and functioning.

Have the option to receive a standard SGB procedure during the study extension phase, if eligible.

This study will enroll approximately 126 participants and aims to improve understanding of how SGB works for PTSD and whether ketamine can enhance its therapeutic effects.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Not yet recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

The most common treatment for Post-traumatic Stress Disorder (PTSD) is trauma-focused therapy and/or prescription of medication(s). However, these treatments may not directly reduce symptoms associated with PTSD, making it difficult for patients to be treated for this condition and recover.

Stellate ganglion block (SGB) is a medical procedure that involves injection of a local anesthetic (a medication that causes reduced sensation/feeling in a given area) around the stellate ganglion, which is a collection of nerves near the base of the neck. This procedure causes a short-lived, temporary shutdown of nerve signals (up to 5-7 hours) and is commonly performed in Canada for certain pain and medical conditions. In the last decade, several studies, including those involving members of military groups, have shown that SGB can result in a rapid and sustained drop in symptoms related to PTSD such as overwhelming anxiety, increased irritability, heightened alertness, and exaggerated startle. Considering these results and the known safety of this procedure (as demonstrated by previous research and use in other illnesses), SGB has been increasingly used to treat PTSD among veterans in the United States but has not yet been thoroughly evaluated in Canada. More research is thereby needed to use SGB as a method of PTSD treatment in Canada, and to better understand how it works to reduce symptoms associated with this condition.

The use of the SGB procedure for PTSD has not yet been approved by Health Canada for the general population.

WHY IS THIS STUDY BEING DONE? The purpose of this study is to better understand how SGB works in helping reduce symptoms associated with PTSD, and to understand if infusing bupivacaine (the standard local anesthetic used for SGB) with ketamine increases the effectiveness of the procedure. Combining ketamine with local anaesthetics such as lidocaine or bupivacaine is a specialized approach used in interventional pain management. Research has shown that this combination works safely in providing powerful relief for severe treatment resistant chronic conditions. However, combining ketamine in the context of an SGB injection, or as a supporting treatment for PTSD symptoms, has yet to be studied.

To do this, the study will have two Parts. The first Part is the Randomized Controlled Trial (RCT), and the second Part is the study extension. In Part I, participants will be randomized into groups where they will either receive one SGB injection of bupivacaine alone, one injection of bupivacaine combined with ketamine, or no injection. We will also be collecting additional information through the use of pupillometry (a non-invasive technique that measures the size and reactivity of your pupil) to monitor the effectiveness of each individual procedure. Additionally, during this project we hope to obtain feedback from both the participant and their family/support network about their experience and satisfaction with the SGB procedure and its effects. This will help us understand for whom SGB works best and will provide us with information and experience for introducing SGB into programs within The Royal. A series of questionnaires will also be asked to understand more about each participant.

In Part II, all participants who meet eligibility criteria, including those who received no injection during Part I, will have the option to finish and exit the study, or continue and receive one standard SGB injection (bupivacaine) during the extension. This means those who received an injection during the RCT will have the option for a second injection, and those who were randomized to the Control Group will have the option to receive one injection.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
126

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Phase 2

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

  • Name: Krysta Boutin-Miller, Research Coordinator
  • Phone Number: 6137226521
  • Email: kboutin@theroyal.ca

Study Locations

  • Canada
    • Ontario
      • Ottawa, Ontario, Canada, K1Z 7K4
        • The Royal
        • Contact:
          • Tammy Beaudoin, Director, Clinical Research
          • Phone Number: 6214 613-722-6521
          • Email: tbeaudoin@theroyal.ca

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years to 69 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  1. DSM-5 diagnosis of PTSD of at least moderate severity confirmed by PCL-5 score ≥33 or CAPS-5 score ≥26 at screening visit
  2. Age 18-69 years
  3. Under care of a mental health clinician
  4. Has not benefited from pharmacological and/or psychological evidence-based treatments for PTSD

Exclusion Criteria:

  1. Assessed with high risk for suicide in the last 30 days
  2. Active mania/ hypomania or psychosis within the last 30 days
  3. Moderate to severe substance use within the last 30 days
  4. In process of disability assessment or legal action
  5. Current participation in another treatment study for PTSD
  6. Pregnancy or breastfeeding confirmed by urine test
  7. Current anticoagulant use (eligible if can be held before the procedure)
  8. History of bleeding disorder
  9. Infection, mass or anatomic abnormalities at target injection site
  10. Myocardial infarction within 6 months of procedure
  11. Pathologic bradycardia or irregularities of heart rate or rhythm;
  12. Symptomatic hypotension
  13. Phrenic or laryngeal nerve palsy
  14. History of glaucoma
  15. Uncontrolled seizure disorder
  16. History of allergy to local anesthetics
  17. History of allergy to general anesthetics
  18. Severe chronic obstructive pulmonary disease (COPD)
  19. Current or reoccurring Pneumothorax
  20. Contralateral pneumonectomy or non-functional lung
  21. Active systemic infection
  22. Bilateral procedure is always contraindicated due to risk of laryngeal/phrenic nerve dysfunction
  23. Participant refusal/inability to tolerate procedure/positioning
  24. End stage renal disease
  25. Known allergy to Ketamine
  26. Unable to hold stimulant or benzodiazepine medication prior to SGB procedure

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Quadruple

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Active Comparator: Group 1: One SGB injection with standard local anesthetic, bupivacaine

One dose of 6mL 0.5% bupivacaine combined with 2ml normal saline. The dose and medication provided to Group 1 is in line with current research practice for SGB which suggests a dosage between 6mL and 9 mL of local anaesthetic. Saline is included in the injection to match the volume of the injection for Group 2 without adding additional medical properties to the solution.
Drug: SGB Bupivacaine

6 mL of 0.5% preservative-free bupivacaine plus 2 mL normal saline
Experimental: Group 2: One SGB injection combining standard local anesthetic, bupivacaine, with Ketamine

The bupivacaine dose administered to Group 2 is identical to that administered to Group 1, with the addition of 20 mg ketamine (2 mL of a 10 mg/mL solution). A fixed ketamine dose of 20 mg was selected to approximate a low-dose (subanesthetic) exposure of 0.3 mg/kg in a 70 kg adult (21 mg), while allowing standardized dosing across participants. This dose was chosen to remain within a range commonly used in clinical research investigating the analgesic and neuropsychiatric effects of ketamine. This is the accepted standard and widely used dose in clinical practice.
Combination product: SGB Bupivacaine + Ketamine

6 mL of 0.5% preservative-free bupivacaine plus 2 mL ketamine (10 mg/mL)

Other Names:
  • Group 2: One SGB injection combining standard local anesthetic, bupivacaine, with Ketamine
No Intervention: Group 3: Treatment as usual

Participants selected to this group will not receive any intervention and continue with their treatments as usual.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Change of the Clinician-Administered PTSD Scale for DSM-5 (CAPS-5) total symptom severity score
Time Frame: From baseline to +4 weeks

The mean difference in the change of the Clinician-Administered PTSD Scale for DSM-5 (CAPS-5) total symptom severity score, specifically evaluated by comparing the Bupivacaine + Ketamine group to the Bupivacaine alone group.
From baseline to +4 weeks
Change of the Clinician-Administered PTSD Scale for DSM-5 (CAPS-5) total symptom severity score
Time Frame: From baseline to +4 weeks

The mean difference in the change of the CAPS-5 total symptom severity score , specifically evaluated by comparing the Bupivacaine + Ketamine group to the Control group.
From baseline to +4 weeks

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
The mean change in PTSD Check List-5 (PCL-5) scores
Time Frame: From baseline to +4 weeks

The mean change in PCL-5 scores between the Bupivacaine + Ketamine group and the Bupivacaine alone group.
From baseline to +4 weeks
The mean change in PCL-5 scores
Time Frame: From baseline to +4 weeks

The mean change in PCL-5 scores between the Bupivacaine + Ketamine group versus the Control group.
From baseline to +4 weeks
Proportion of patients achieving reliable change (at least 14-point reduction) in the total score on Outcome Questionnaire 45 (OQ45)
Time Frame: from baseline to +4, +8 and +12 weeks.

Proportion of patients achieving reliable change (at least 14-point reduction) in the total score on OQ45.2 reflecting improvement in symptom burden and functioning
from baseline to +4, +8 and +12 weeks.
Changes in participant's symptomatology and overall functioning from the perspective of the participant's family and support network measured by the FAST-Q
Time Frame: From baseline to +4 and +12 weeks

Changes in participant's symptomatology and overall functioning from the perspective of the participant's family and support network measured by the FAST-Q
From baseline to +4 and +12 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
The Royal's Institute of Mental Health Research

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Rebecca J Gomez, MD, Research Institute (IMHR) at The Royal, Ottawa campus

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
February 1, 2027

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
February 1, 2029

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
February 1, 2029

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
November 3, 2026

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 3, 2026

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
November 9, 2026

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
November 9, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 3, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
November 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 300167

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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