Lori,
Blood oxygenation levels have no relationship to the cluster headache abortive effect of 100% oxygen.
Tell the physician, the oximetery test is for COPD, NOT OXYGEN THERAPY FOR CLUSTER HEADACHE !!!! THESE ARE TWO ENTIRELY DIFFERENT MEDICAL CONDITIONS AND SO ARE THE METHODS OF PROCEDURE IN ADMINISTERING OXYGEN THERAPY !!!
I've got a finger pulse oximeter and road out several cluster headaches with 99% SpO2 for up to an hour without any relief at an oxygen flow rate of 7 to 9 liters/minute and a only slightly better response at 15 liters/minute.
It wasn't until I increased the oxygen flow rate up to 25 liters/minute and above that I started to experience what we call rapid aborts of cluster headache attacks in the 4 to 7 minute range to a pain free response.
The most effective methods of oxygen therapy as an abortive for cluster headache involve 100% oxygen flow rates that support hyperventilation ≥25 liters/minute with 40 liters/minute being optimum for the fastest aborts.
What makes oxygen therapy most effective is casting off CO2 faster than the body generates it through normal metabolism. This results in respiratory alkalosis, hypocapnia (lower than normal arterial CO2 levels) and an elevated arterial pH... These conditions in turn stimulate the rapid vasoconstriction that's associated with very fast and very safe cluster headache aborts with oxygen therapy.
The CH'er needs to intentionally hyperventilate with 100% oxygen until the symptoms of respiratory alkalosis are clearly present. These symptoms are also called paresthesia. They include a slight tingling or prickling of the lips, finger tips and back of the neck. The CH'er might even experience a very slight dizzines. These symptoms are VERY NORMAL when hyperventilating with 100% oxygen and they are VERY SAFE...
I have prayed to pass out using this method of oxygen therapy and in 11 years of using it... that never happened.
See the following link for a detailed level of information how and why this method of oxygen therapy is so effective:
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I developed the original method of oxygen therapy at flow rates that support hyperventilation in 2005. In 2007, Michale Berger and I modified that procedure to work with an oxygen demand valve provided by Royce Fishman who was working for Linde at the time. We filed the above patent when the results of our own pilot study indicated this method of procedure was far superior to oxygen therapy at a flow rate of 15 liters/minute. See the results of our pilot study of oxygen therapy at flow rates that support hyperventilation in following comparison with oxygen therapy at a flow rate of 15 liters/minute:
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Participants in this study logged abort times and pain levels on every cluster headache they aborted with oxygen therapy for 8 weeks...
They compiled a total of 366 aborts using oxygen therapy at flow rates that support hyperventilation or with a demand valve... Both methods worked equally well with the 7 participants using a 0-60 liter/minute oxygen regulator from Flotec or an Oxygen Demand Valve.
Try to get your husband the lab test for 25(OH)D when he sees the neurologist on Monday... He is likely vitamin D3 deficient and that deficiency is contributing to the frequency, severity and duration of his cluster headaches. The anti-inflammatory regimen with 10,000 IU/day vitamin D3 is the latest, safest and most effective method of preventing cluster headache... No reports of serious side effects...
Take care and please keep us posted.
V/R, Batch