A Multicenter Double Blinded Randomized Controlled Trial of the Efficacy of the Sphenopalatine Ganglion Block for the Treatment of the Postdural Puncture Headache After Labor Epidural

The postdural puncture headache (PDPH) is a well-documented complication of dural puncture. Depending on a number of factors, the overall incidence of PDPH following unintended dural puncture with an epidural placement needle is typically around 50%, but can be as high as 70% for certain populations.(1, 2, 3)

The headache is characterized by being frontal or occipital in nature, with a typical onset of 6-72 hours after dural puncture. It is normally exacerbated by the upright position and improved by the supine position. Associated symptoms may include photophobia, nausea, vomiting, dizziness, tinnitus, neck stiffness, decreased hearing and visual changes. (2) These symptoms tend to be extremely debilitating in affected patients, severely limiting their functional capacity until the resolution of the headache.(2) The compromise is even greater when considering these women also need to care for a newborn, as the time after birth is important for forming attachment and encompasses many new obligations for the new mother.

The treatment of the PDPH often begins with conservative treatment including supportive therapies such as hydration, bed rest, acetaminophen, NSAIDs, and oral opioids. In addition, some evidence exists for the use of caffeine (1,2). While these do not hasten recovery, they may improve symptoms. For PDPH of all etiologies, 72% will resolve spontaneously in 7 days and 89% by 14 days. (1)

For patients with moderate to severe symptoms or long lasting headaches, the gold standard for treatment of headaches that do not resolve is the epidural blood patch (EBP) (1,2,4). This treatment has been shown to be effective in 70-98% of patients (1,2,4). However, it has numerous contraindications including: fever, infection, coagulopathy, active neurological disease, patient refusal. In addition, a potential complication is yet another dural puncture. Also, while the EBP is generally very safe, it is an invasive procedure with its own complications; it has been associated with very rare but serious complications including: moderate long-lasting backache, meningitis, epidural abscess formation, epidural hematoma formation, and neurologic deficit development. (5-8)

The sphenopalatine ganglion (SPG) is a parasympathetic ganglion with fibers that innervate the cerebral and meningeal blood vessels cause vasodilation and activation of nociceptive fibers in the meninges, which is perceived as referred pain from the head by the sensory cortex. (9) So blockade of these fibers can theoretically relieve headache symptoms from other causes. The SPG block has been safely used for many years to treat chronic facial or head pain from cluster headaches, trigeminal neuralgia, postherpetic neuralgia, atypical facial pain from cancer, and CRPS I and II. (9)