Intranasal Sphenopalatine Ganglion Blockade for Headaches Following Aneurysmal Subarachnoid Hemorrhage

Description

Spontaneous subarachnoid hemorrhage (SAH) accounts for up to 8% of strokes and affects approximately 30,000 individuals yearly in the US alone. Of those, ruptured intracranial aneurysm is the etiology up to 85% of the time. In these patients, severe headache is the most common complaint and its treatment is difficult and often inadequate. However, adequate. Opioids, often in escalating doses, are guideline recommended, but unfortunately they have significant side effects and are often not effective. There have been numerous trials looking at different treatments for the headache caused by SAH. There is an urgent need for an effective treatment with tolerable side effects. The pathophysiology of pain in aneurysmal subarachnoid hemorrhage (aSAH) is not well elucidated.

It is likely related to vasoactive and inflammatory byproducts of blood degradation in the subarachnoid space. The intracranial vessels themselves are abundantly innervated, predominantly by branches of the maxillary nerve. The sphenopalatine ganglion (SPG) is a possible target for intervention, as blockade has been shown to be effective in cluster headaches. The SPG is located near the maxillary nerve, which may explain why blockade is also useful in several other head pain disorders. A small, single center pilot study of seven patients evaluated a bilateral suprazygomatic pterygopalatine fossa blockade as a treatment for headache, and all the patients had clinically significant reductions in reported pain. This study aims to evaluate whether intranasal SPG blockade could provide an effective and minimally invasive treatment option to improve pain and possibly reduce opioid requirements in these patients.