The Effect of Ganglion Sphenopalatine Block (GSP-block) Versus Placebo on Postdural Puncture Headache

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 (GSP block) on postdural puncture headache.

Detailed Description
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Adult patients with postdural puncture headache will be enrolled in the study. The patients will be randomised to receive a ganglion sphenopalatine block (GSP-block) with either local anesthetic (lidocaine + ropivacaine) or 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 postdural headache in standing position 30 minutes after block. If the patients in the timeframe of 1 hour to 1 week after block does not achieve remission (VAS <30mm while standing) they will be offered a rescue GSP-block defined as a new GSP-block with open-label local anesthetic and if continued lack of remission at least 1 hour thereafter then an epidural blood patch will be offered.

Official Title
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The Effect of Ganglion Sphenopalatine Block (GSP-block) Versus Placebo on Postdural Puncture Headache: a Blinded Randomized Clinical Trial

Conditions
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Postdural Puncture Headache, Sphenopalatine Ganglion Block

Intervention / Treatment
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* Procedure: Ganglion sphenopalatine block with local anesthetic
* Procedure: Ganglion sphenopalatine block with placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age > 18 years Patients with postdural puncture headache defined as moderate to severe postural headache (VAS >= 30mm) after lumbar puncture or accidental dural puncture during epidural insertion with an onset within 3 days following the puncture. Lack of headache remission within 1 day after dural puncture and after treatment with fluids, caffeine and paracetamol Patients who have given their written informed consent for participation in the study after fully understanding the protocol content and limitations. 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

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: Local anesthetic<br> | Procedure: Ganglion sphenopalatine 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: Isotonic NaCl<br> | Procedure: Ganglion sphenopalatine block with placebo<br>* Block performed with bilaterally inserted q-tips with isotone NaCl<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. | 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 |
| --- | --- | --- |
| Pain rating (0-100mm on a visual analogue scale, VAS) in standing position | 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. | 1 hour after block and 1 week after block | 
| 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 after block | 
| Number of patients needing rescue GSP-block |  | During study period until completion of 1 week follow up | 
| Number of patients needing a epidural blood patch |  | During study period until completion of 1 week follow up | 
| Pain rating (0-100mm on a visual analogue scale, VAS) in supine position |  | 30 minutes after block, 1 hour after block and 1 week after block |