I was good with the numbers until I saw the reference to "93% or lower" requiring supplemental oxygen. In my personal experience with athsma the target number for relief from hypoxia was 90% oxygenation on the SpO2 reading from the pulse oximeter. Medicare generally won't pay for home oxygen gear unless your oxygenation drops to 88% or less for at least 5 minutes a night while one is sleeping. This leads me to scratching my head over the articles stated concern over an oxygenation saturation level of 93%. My athsmatic and COPD suffering aquantances are generally grinning with relieved Glee on discovering their SpO2 to be as high as 93%. I could be wrong somehow: my authority on the matter isn't absolute. But 93% SpO2 sounds mighty high in the community of COPD sufferers and athsmatics to be setting off panicky alarm bells!