The Effect of Ganglion Sphenopalatine Block Versus Placebo on Persistent Headache Following COVID-19 Infection

Study Overview
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Brief Summary
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The purpose of this study is to evaluate the effect of the ganglion sphenopalatine block (SPG block) on persistent headache following acute COVID-19 infection.

Detailed Description
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Adult patients with persistent headache following COVID-19 infection will be enrolled in the study. The patients will be randomised into three groups; bilateral SPG-block withto receive local anesthetic (lidocaine + ropivacaine), bilateral SPG-block with placebo (isotone NaCl) or bilateral sham-block with placebo (isotone NaCl). Primary outcome is hyperactivity in the sphenopalatine ganglion assessed by pain intensity (0-100mm on a visual analogue scale, VAS) of the headache in standing position 30 minutes after block in the group Ropicavain-Lidocain and sham.

Official Title
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The Effect of Ganglion Sphenopalatine Block (SPG-block) Versus Placebo on Persistent Headache Following COVID-19 Infection: a Randomised, Blinded, Clinical Trial

Conditions
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Headache, Covid19, Sphenopalatine Ganglion Block, Persistent Headache Following COVID-19

Intervention / Treatment
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* Procedure: Sphenopalatine Ganglion Block with Local Anesthetic
* Procedure: Sphenopalatine Ganglion Block with Placebo (Isotone NaCl)
* Procedure: Sham-block with Placebo (Isotone NaCl)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age > 18 years Moderate to severe headache (NRS >= 3) with self reported duration of minimum 6 hours during the past week as well as moderate to severe headache (NRS >= 3) on the day of intervention. Onset of headache during or maximum 4 weeks after PCR-verified COVID-19 infection. Headache must have persisted for at least 4 weeks following COVID-19 diagnosis. Exclusion Criteria: Patients who cannot cooperate to the study Patients who does not understand or speak Danish Allergy to the drugs used in the study Has taken opioids within 12 hours prior to intervention History of migraine or persistent headache before COVID-19 infection. Active COVID-19 infection (defined by the Danish Goverment regulations, i.e. 48 hours after last symptoms (omitting long term effects) or 7 days after positive COVID-19 test if no symptoms.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Ropivacaine-Lidocaine<br> | Procedure: Sphenopalatine Ganglion Block with Local Anesthetic<br>* Block performed with bilaterally inserted q-tips with 1:1 mixture of lidocaine 40mg/ml and ropivacaine 5mg/mL<br>|
| Placebo Comparator: Placebo<br> | Procedure: Sphenopalatine Ganglion Block with Placebo (Isotone NaCl)<br>* Block performed with bilaterally inserted q-tips with isotone NaCl<br>|
| Sham Comparator: Sham-block with Placebo<br> | Procedure: Sham-block with Placebo (Isotone NaCl)<br>* Block performed with bilaterally inserted q-tips with isotone NaCl. The q-tips are inserted a maximum of 3 cm into the nasopharynx thus not reaching the mucus above the ganglion.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Hyperactivity in the sphenopalatine ganglion assessed by pain intensity (0-100mm on a visual analogue scale, VAS) of the postdural headache in standing position in the group Ropivacine-Lidocaine and sham. | Pain intensity will be measured as worst experienced pain after the patient has been standing for 30 seconds or the worst experienced pain while attempting to stand if the rating has to be interrupted. | 30 minutes after block | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of patients with pain rating below 30mm in standing position (0-100mm on a visual analogue scale, VAS) | Pain intensity measured as worst experienced pain after the patient has been standing for 30 seconds or the worst experienced pain while attempting to stand if the rating has to be interrupted. | 30 minutes and 1 week after block | 
| Worst experienced pain in standing position (0-10 on a numercial rating scale, NRS) | The worst experienced pain reported during the week following the block as registered by the patient. | During study period until completion of 1 week follow up | 
| Average pain intensity (0-10 on a numercial rating scale, NRS) | The average pain intensity reported during the week following the block as registered by the patient. | During study period until completion of 1 week follow up | 
| Number of patients needing rescue GSP-block | If the patient at the 1 week follow up still needs further treatment a rescue SPG-block defined as a new SPG-block with open label analgetics will be offered. | At 1 week follow up | 
| Hyperactivity in the sphenopalatine ganglion assessed by pain intensity (0-100mm on a visual analogue scale, VAS) of the postdural headache in standing position in all 3 groups. | Pain intensity will be measured as worst experienced pain after the patient has been standing for 30 seconds or the worst experienced pain while attempting to stand if the rating has to be interrupted. | 30 minutes after block |