Would o2 levels be normal on a stress test if someone had copd?

Can be...: Many patients with COPD have low oxygen levels, even without exercise. However, many also have normal oxygen levels. Some patients will be normal at rest and activity will cause the oxygen level to drop. Occasionally, supplemental oxygen will be needed. Stress tests in patients with underlying lung disease are usually done with monitoring of the oxygen level, and oxygen can be given if needed.

t depends on severit: It depends on the severity of copd. In severe COPD 02 saturations of the blood can drop with mild exertion, whereas with mild COPD o2 saturation may rise normally. In moderately severe COPD the o2 sat may remain the same. With severe COPD the o2 can't get in the blood fast enough on heavy exertion and the o2 sat falls in the blood .This is due to airways obstruction and rupture of the air sac wa.

COPD and stress test: It depends on the "severity" of your copd. Some people are obstructed but have no problem with their oxygen level. You cannot rule out COPD or emphysema just based on a stress test. You can say that if you had copd, it is not that severe since your oxygen remained normal. To rule out copd, one has to undergo pft or pulmonary function tests which would let us know if your airways are obstructed.