A Pilot Study of Demand Valve Oxygen Inhalation Therapy for Cluster Headache

Overview

Cluster headache is a disorder marked by frequent attacks of short-lasting, severe, unilateral head pain with associated autonomic symptoms. It is the most severe head pain syndrome known. Currently, the two most common treatments for cluster headaches are inhaled oxygen and injectable sumatriptan. These treatments do not work for all cluster headache patients, and patients who smoke may eventually develop contraindication to triptans. New treatment options are needed. An alternative method of oxygen delivery (as opposed to continuous flow) uses a demand valve that is controlled by respiration rate, allowing increased oxygen flow in response to increased demand. This system may be more efficacious at stopping a cluster headache attack than the currently prescribed oxygen delivery system. This study will compare the effectiveness of oxygen delivered via demand valve versus continuous high flow oxygen via non-rebreather face mask in the acute treatment of a cluster headache attack. All patients will treat one cluster headache with each of the 2 treatment methods.

Cluster headache is a primary headache disorder marked by frequent attacks of short-lasting, severe, unilateral head pain with associated autonomic symptoms. The goal of acute therapy for cluster headache is fast, effective and consistent relief. In the currently recommended dosing strategy of continuous flow 100% oxygen given via a non-rebreather face mask at 7-15L/min, the time to improvement can sometimes take upwards of 20-30 minutes and is not effective for all cluster headache sufferers. An alternative method of oxygen delivery (versus continuous flow) uses a demand valve which is controlled by the respiration rate, allowing increased oxygen flow in response to increased demand. This delivery system may be better at stopping a cluster headache attack than the continuous flow model as it can support hyperventilation which can enhance cerebral arterial vasoconstriction via a state of hyperoxia and hypocapnia. Arterial vasoconstriction is one hypothesized method by which oxygen can abort a cluster headache attack. This proof of concept trial will evaluate if oxygen delivered via demand valve with a specific breathing technique is effective as a cluster headache acute treatment and is more effective than the traditional continuous high flow oxygen treatment with a non-rebreather face mask.