Clarification on diagnosis

I have been diagnosed with sleep apnea for about a year now but the standard treatment of CPAP is innefective. After some time struggling with the machine I was eventually admitted for overnight monitoring and then trials with alternative machines.
When trialling with a BIPAP machine we found that we could not set it up to breath at my natural rate. It is difficult to ***** your own breathing patterns without affecting them in some way but it would appear my natural rythym is approximately 6-8 breaths per minute with a pause of three to four seconds between the exhalation phase and the next cycle. As we could not get the 1st machine (a NIPPY +) to go below 12 Breaths/min I presume mine is abnormally slow.
Is it feasable that my unstrained pause between cycles be mis-recorded as an apneic event or is this still classified as apneac but central rather than obstructive?
Other symptoms include headaches with some visual disturbances, variably low blood pressure being 100-110/75 resting but with bouts as low as 85-90/55 but no recordable postural effects, poor concentration, depression and moods.

[Steven Y Park, MD]

A pause has to last 10 seconds or longer to be classified as an apnea, whether obstructive or central. A 3-4 second pause won't get counted.