Efficacy of Sphenopalatine Block Compared to Blood Patch in the Management of Post-dural Puncture Headaches

Efficacy of Sphenopalatine Block Compared to Blood Patch in the Management of Post-dural Puncture Headaches

Post-dural puncture headache (PDPH) is an iatrogenic complication following a dural puncture, which may occur after lumbar puncture, spinal or epidural anesthesia. These headaches are defined as positional headaches, which worsen in the upright position and improve in the supine position, occurring within 5 days after a dural puncture.

PDPH is disabling, particularly in the postpartum period and is often associated with symptoms such as nausea, vomiting, neck stiffness, photophobia, and hearing loss. While serious immediate complications (e.g., subdural hematoma, cerebral venous thrombosis) are rare, long-term consequences - including chronic headaches, neck or low back pain and depression, have been described.

A conservative treatment is usually started during the first 24 hours, but it often proves insufficient, leading to the use of an additional epidural blood patch therapy. While considered as the gold standard, this procedure is invasive and presents limitations. The effectiveness of the epidural blood patch is variable (33-91 %), and the need for a second blood patch is not uncommon. The risks associated with the procedure include second dural puncture, low back pain, vasovagal syncope and paresthesia. Serious complications could occur with reported cases of aseptic meningitis or acute subdural hematoma.

An emerging alternative is the sphenopalatine ganglion block that is a less invasive procedure showing promising results. Several recent trials suggested the safety, feasibilty and efficacy of this intervention with excellent tolerance. Then, we aim to compare the efficacy and safety of these procedures in a randomized controlled trial.

This is a single-center interventional study classified as a clinical drug trial (European Regulation n°536-2014).

Patients suffering from post-dural puncture headache resistant to medical treatment for 24 hours are refered by the treating physician to the referent anesthesia team for consultation.

Patient screening for the study is realised and study information is delivered by the anesthesia team. After the verification of inclusion and non-inclusion criteria, inform consent is searched. The patient is managed either with an epidural blood patch or a sphenopalatine ganglion block, depending on the group of randomisation. During at least 30 minutes post-intervention, patients are monitored in the post-anesthesia care unit.

Headache intensity is assessed using the numerical rating scale just before the intervention and at 30 minutes, 1 hour, 2 hours, 6 hours, 24 hours, 48 hours and 7 days post-intervention. All secondary outcomes are evaluated during the 7 days after the intervention. This assessment is carried out by a clinical research associate blinded to the treatment allocation.

The patient will be hospitalized for at least 6 hours and if the treatment is ineffective after 24 hours, a rescue therapy with an epidural blood patch will be mandated, regardless of the patient's randomization group. If the patient is discharged within 7 days follow up the intervention, the numerical rating scale and secondary outcomes assessments will be conducted by telephone.

Inclusion Criteria:

• Patients with post-dural puncture headache meeting the criteria of the International Classification of Headache Disorders (ICHD-3) and persisting after 24 hours of conservative treatment,
• Patients aged over 18 years,
• Patients affiliated to a social security health insurance system,
• Patients who have provided written informed consent.

Exclusion Criteria:

• Patients under legal protection (guardianship or curatorship), deprived of liberty (prisoners), or under judicial safeguard,
• Pregnant patients,
• Patients with hypersensitivity to lidocaine, prilocaine, local anesthetics of the amide type, or to any of the excipients listed in the composition of the drugs used in the protocol,
• Patients with acute porphyria, atrioventricular conduction disorders requiring permanent cardiac pacing not yet implemented, or epilepsy not controlled by treatment,
• Patients receiving antiarrhythmic therapy associated with torsades de pointes (amiodarone, disopyramide, quinidine derivatives, sotalol, etc.),
• Patients with atypical post-dural puncture headache suggestive of a post-dural puncture complication (altered consciousness, focal neurological deficit, seizures, visual disturbances, etc.),
• Patients with chronic headaches requiring preventive treatment,
• Patients with a history of spinal surgery precluding the performance of an epidural blood patch,
• Patients with contraindications to epidural blood patch (local or systemic infection, platelet count < 80 G/L, coagulation disorders, progressive neurological disease),
• Patients with contraindications to sphenopalatine ganglion block (nasal polyposis, rhinopharyngitis, deviated nasal septum).