Use of oxygen therapy in cluster headache patients
Cluster headache patients require effective abortive therapy due to the extreme intensity of their pain. The two most effective cluster abortives are injectable sumatriptan and inhaled oxygen. However, since a large percentage of cluster sufferers are cigarette smokers and at high risk of coronary artery disease, many cannot be treated with the various triptan medications. In these cases, oxygen therapy becomes the preferred option.
Oxygen, the safest of all cluster therapies, is usually prescribed based on a landmark study by Dr. Lee Kudrow. In this study, patients were instructed to use 100% oxygen via a nonrebreather face mask at 7-10 liters/minute. Although usually effective, a certain subset of cluster patients do not achieve relief from this treatment. Todd Rozen, MD, while a physician at MHNI, hypothesized that treating patients with higher flow rates of oxygen, up to 15 liters/minute, might provide relief to those sufferers who had not responded to standard oxygen therapy regimens.
High oxygen flow rates
Because MHNI has many intractable cluster patients, it was decided that a higher dose of oxygen therapy would be utilized in a few patients. Several important cases recently reported in the medical literature found this therapy to be quite effective in patients who previously did not respond to lower dose oxygen inhalation.
MHNI's experience indicates patients who do not respond to standard flow rates should be given the opportunity to use up to 15 liters/minute. However, prior to initiating this therapy, patients must obtain clearance from their primary care physician since serious lung disease or other conditions can make oxygen therapy unsafe or inappropriate. In addition, such oxygen therapy should not be used for more than a maximum of 10-20 minutes at a single setting.
The basis by which oxygen turns off a cluster headache is unknown at this time. Oxygen's constrictive effect on cerebral blood vessels may play a significant role.
Further study and a larger sample size is needed to provide conclusive evidence regarding the usefulness of high oxygen flow rates for difficult-to-treat cluster headache patients.