This single-center, randomized, controlled, single-blind clinical trial evaluates whether a stellate ganglion block (SGB) using bupivacaine can improve persistent symptoms in adults with long COVID. Participants are assigned in a 1:1 ratio to receive either an ultrasound-guided right-sided SGB or a placebo saline injection delivered to the sternocleidomastoid muscle. After the intervention, participants are followed for 26 weeks with scheduled evaluations that include symptom questionnaires and functional tests.
The study assesses changes in functional status, fatigue, cognitive complaints, quality of life, dyspnea, lower-limb endurance, and orthostatic tolerance over time. Safety is monitored throughout all follow-up visits. Approximately 40 participants meeting predefined eligibility criteria will be enrolled. This trial seeks to determine whether a single stellate ganglion block has an effect on persistent long-COVID symptoms compared with placebo.The results will help determine the therapeutic value of SGB in the management of long COVID and inform future research and clinical practice.
Adults aged 18 years and older
Positive COVID-19 test confirmed by RT-PCR, antibody test, or antigen test at least 3 months prior to randomization, OR presumed COVID-19 evaluated by the site investigator (no positive test required) with an acute illness occurring after October 15, 2019 and at least 3 months prior to randomization.
Persistent symptoms ≥12 weeks after onset of acute COVID-19 AND symptoms lasting at least 2 months. The onset date is defined as the earliest of: date of first positive test, date of first symptoms
Post-COVID Functional Status Scale score ≥2.
Prior diagnosis of myalgic encephalomyelitis (ME) or fibromyalgia
Being on sick leave or disability at the time of the original acute COVID-19 infection.
Pregnancy or breastfeeding.
Myocardial infarction within the last 12 weeks.
Parallel
Stellate Ganglion Block (Bupivacaine)
Procedure/SurgeryA single ultrasound-guided stellate ganglion block is administered on the right side of the neck under sterile conditions by an anesthesiologist. The needle is positioned between the longus colli muscle and the right carotid artery, and 7 mL of 0.5% bupivacaine is injected. Correct placement is verified by ultrasound and confirmed clinically by the expected appearance of Claude Bernard-Horner syndrome following the injection. Participants are observed for approximately 30 minutes after the procedure.
placebo saline injection
Procedure/SurgeryA single placebo injection of 6-8 mL of 0.9% normal saline is administered into the right sternocleidomastoid muscle. The procedure uses the same patient positioning, sterile preparation, and ultrasound guidance as the active arm; however, the needle is intentionally placed in the muscle, away from the stellate ganglion, and does not produce a stellate ganglion block (i.e., cannot cause Claude Bernard-Horner syndrome).
Post-COVID-19 Functional Status Scale (PCFS)
The PCFS measures limitations in daily functioning related to persistent post-COVID-19 symptoms. Scores range from 0 (no functional limitation) to 4 (severe functional limitation). Assesses changes in functional status over time.
Fatigue Severity Scale (FSS)
The FSS is a validated 9-item questionnaire assessing the impact of fatigue on daily activities, motivation, and functioning. Each item is scored from 1 to 7; higher scores indicate greater fatigue severity. Clinically significant change is defined as ≥0.45 points.
Brain Fog Scale (BFS)
The BFS is a 23-item questionnaire evaluating cognitive symptoms associated with Long COVID, including mental fatigue, cognitive clarity, logical thinking, and concentration. Total scores range from 0 to 92, with higher scores indicating more severe cognitive impairment.
Health-Related Quality of Life (SF-36)
The SF-36 is a validated 36-item questionnaire assessing eight domains of health-related quality of life, including physical functioning, limitations due to physical or emotional problems, pain, general health, vitality, social functioning, and mental health. Higher scores reflect better perceived health and functioning.
Dyspnea Severity (mMRC Scale)
The modified Medical Research Council (mMRC) Dyspnea Scale is a 0-4 grading system that assesses the degree to which breathlessness limits daily activities. Higher grades indicate greater functional limitation due to dyspnea. It is the only validated French-language scale measuring dyspnea in daily activities.
Lower-Limb Muscle Endurance (1-Minute Sit-to-Stand Test)
The 1-Minute Sit-to-Stand Test (1STST) measures lower-limb muscular endurance by counting the number of sit-to-stand repetitions a participant completes in one minute from a standard chair without armrests. It is reliable, sensitive, and well-tolerated in populations with impaired physical capacity. Higher counts indicate better endurance.
Orthostatic Intolerance (NASA Lean Test)
The NASA Lean Test assesses orthostatic intolerance by measuring heart rate and blood pressure changes during 10 minutes of standing with the back supported against a wall. Results help identify symptoms such as dizziness, palpitations, or light-headedness related to positional changes. If a participant cannot complete 10 minutes, the test is still considered valid.
Click on the lead sponsor to view all of their trials.
