Was diagnosed with mild OSA (AHI of 12.5) in late 2012. I had also been diagnosed with a deviated septum since 2001 which in time I believe has worsened.
Here are my findings using a ChoiceMed W11SM pulse oximeter:
NO TREATMENT (external nasal strip only):
Avg Sp02 <88: 180
Avg event level: 84
Lowest level: 81
Other: morning hypertension
BIPAP+ external nasal strip :
Avg Sp02 <88: 56
Avg event level: 86
Lowest level: 84
Other: morning hypertension; chronic dry mouth following usage; mouth-breathing because could not breathe through nose
OASYS ORAL DEVICE (OSA mandibular advancement device) + external nasal strip:
Avg Sp02 <88: 389
Avg event level: 82
Lowest level: 80
Other: morning hypertension; transient intermittent TMJ/TMD after a few night usage
O2 CONCENTRATOR + external nasal strip :
Avg Sp02 <88: 16
Avg event level: 85
Lowest level: 78
Other: morning hypertension, but better
Pulse rate spikes in the majority of desaturation events but not in all cases; can be immediate spike in PR or a gradual response to varying levels of desaturation or sometimes with no desaturation at all.
02 + external nasal strip resulted in 12 out of 34 sessions with Sp02 of 88 or greater. There was a much higher average >95 Sp02 than with the other treatments. I suspect <88 Sp02 results are mostly due to transient nasal congestion.
By far, the 02 concentrator direct to the nostrils via cannula @ a 4-5+ setting with humidifier cup attachment + external nasal strip produces the best results and the least desaturation events <88 (most consistent 02 @ 98).
Although I have not had a followup polysomnography to confirm 100%, my preliminary findings would indicate that my intermittent nocturnal hypoxia/hyponeas stem from my nasal obstruction/constriction/congestion mainly due to the deviated septum and possible rhinosinusitis due to airborne allergens.
My ENT doc was right all along when all the other docs said a deviated septum/nasal congestion does not cause OSA. This goes to show that not all OSA is related to soft tissue/throat issues.
Would welcome any additional input.