Why do some patients only need 4-5 hours of oxygen and others more?

Great question! Some of it has to do with CO2 levels in the lungs. Lungs that have been injured by COPD, cancer, or other disease don't always exchange oxygen efficiently. They tend to trap CO2 so the lungs aren't able to oxygenate the blood fully. Every bodily function is negatively affected.

While I don't fully understand the whys of the times assigned some can clear the CO2 within a reasonable amount of time and don't require supplemental oxygen constantly. Doctors want the PO2 level to be above 92.

There are other factors that influence supplemental O2. Among them heart disease. An impaired heart cannot pump blood efficiently and supplemental O2 keeps the levels high enough that the heart doesn't have to strain too hard to do its job. The people in my family who are on 24 hour O2 have heart issues.

There's more to this and someone who knows more should be checking in soon.

Thank you! My oximeter reads normal BUT I am out of breath and need to use my oxygen. I do have bilateral Lung Cancer, with no progression at this time. It’s weird……I think of my lungs as a battery that needs to be charged with oxygen for 4-5 hours in the AM.

I would appreciate any input…..

ANYONE ELSE experience this?!!

O2 level needs depends on what you are doing at the time and your health conditions, lung capabilities. The more you move the more O2 required. And when we sleep our breathing is lower, OK for healthy people but compromised people need help. For example, just sitting on the sofa, my O2 is fine, but for exercise and sleeping I require oxygen supplement.
My diagnosis includes at least 3 reasons for shortness of breath: 1) interstitial pulmonary fibrosis as a previous smoker 2) Episode of radiation pneumonitis with remaining scar tissue 3) Possible pulmonary hypertension, reduced right ventricular function.

I understand using oxygen for exercise but may I ask why do you use oxygen while sleeping?

Thank you so much for your input!

Janna

I did the overnight oximetry test and it showed significant time of O2 below 89% and some evidence of sleep-related disordered breathing. Specialist said since I needed O2 with exertion, he would be surprised if I didn't need it at night as well.

Everyone, not just those with lung issues, breathes more shallowly when asleep. It's not a problem for those with healthy lungs, but it becomes one for those who have reduced lung capacity. Without supplementary oxygen, my O2 goes below 86 when sleeping.