Cervicothoracic Sympathetic Block Evaluation for Post COVID Condition

ConditionAutonomic Dysfunction

Trial statusRecruiting

Trial phasePhase 4

Trial typeInterventional

Biological sexAll

Age18+

SponsorUniversity Health Network, Toronto

About this trial

Post-COVID Condition (PCC) affects roughly 2.1 million Canadians, carrying an annual economic burden of CAD $7.8-50.6 billion. It presents across multiple organ systems with symptoms including fatigue, brain fog, palpitations, and orthostatic intolerance, at an annual cost of CAD $1,675-$7,340 per case.

A key mechanism underlying many treatment-resistant PCC symptoms appears to be dysautonomia abnormal autonomic nervous system function driven by immune-mediated sympathetic overactivity. Persistent inflammation (cytokine storms, T/B-cell dysfunction, microclots) sustains sympathetic hyperactivity, which in turn perpetuates systemic inflammation and "sickness behaviors" resembling PCC symptoms.

Current treatments including beta blockers, ivabradine, fludrocortisone, and rehabilitation are limited by variable responses, side effects, and the complication of post-exertional symptom exacerbation. Emerging therapies (SSRIs, low-dose naltrexone, antihistamines, HBOT) show promise but lack robust trial evidence.

Cervicothoracic sympathetic chain block (CSB) a local anesthetic block of the cervical and upper thoracic sympathetic ganglia is a promising intervention that reduces sympathetic outflow, improves cerebral blood supply, and lowers pro-inflammatory cytokines. Small observational studies (16 studies, 224 patients) show benefit for PCC symptoms, but all lack placebo controls and have significant methodological heterogeneity.

The proposed study aims to fill this gap with a double-blind, placebo-controlled RCT to rigorously evaluate CSB's efficacy, magnitude of benefit, and durability in PCC patients.

Eligibility criteria

This trial does not accept healthy volunteers

Qualifiers

Age 18 years or older

PCC following COVID-19 infection with symptoms lasting for at least three months

Ability to read, write, and understand English

Quantified autonomic symptoms from at least one domain as reported by the patient on the screener Composite Autonomic Symptom Score (COMPASS-31), i.e. a COMPASS-31 score greater than 0. COMPASS-31 assesses 6 domains of autonomic symptoms: Orthostatic Intolerance, Vasomotor, Secretomotor, Gastrointestinal, Bladder, and Pupillomotor.

Disqualifiers

Unilateral vocal cord paralysis; Severe chronic obstructive pulmonary disease (FEV1 between 30-50% of predicted value)

Recent myocardial infarction (within the last one year), Cardiac conduction block of any degree

Glaucoma

Infection or mass at injection site, bleeding disorders

Trial design

Design model

Parallel

Treatments tested in this trial

5 mL of 0.25% bupivacaine with epinephrine (1:200,000)
Drug
The active group will have cervical sympathetic block (CSB) on both the left and right sides using up to 5 mL of 0.25% bupivacaine with epinephrine (1:200,000). After the injection, all patients will be monitored for a minimum of 30 minutes to check for expected effects of the block and to watch for any side effects or complications.
Sham Group
Other intervention
The sham group will have cervical sympathetic block (CSB) on both the left and right sides using up to 5 ml of normal saline (0.9% NaCl). After the injection, all patients will be monitored for a minimum of 30 minutes to check for expected effects of the block and to watch for any side effects or complications.

Treatment groups

78 Participants

are divided into 2 treatment groups

Group A: Active groupExperimental treatment 1 intervention

Group B: Sham groupPlacebo comparator 1 intervention

Trial outcomes

Primary outcomes

Cardiac dysautonomia-related symptoms

Evaluate the effects of stellate ganglion blocks on heart rate associated with postural changes in patients with PCC.

Time frame

4-week

Cardiac dysautonomia-related symptoms

Evaluate the effects of stellate ganglion blocks on blood pressure associated with postural changes in patients with PCC.

Time frame

4-Week

Sponsors and contacts

Click on the lead sponsor to view all of their trials.

University Health Network, Toronto

Lead sponsor

Source ClinicalTrials.gov

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