How Is COPD Diagnosed?

7 answers | Last updated: Nov 10, 2016
A fellow caregiver asked...

How is COPD diagnosed?

Expert Answers

Dr. Leslie Kernisan is the author of a popular blog and podcast at She is also a clinical instructor in the University of California, San Francisco, Division of Geriatrics.

To diagnose chronic obstructive pulmonary disease (COPD) for sure, a doctor needs to order pulmonary (lung) function tests. These are special tests that provide measurements of:

  • How much air a person's lungs can hold (the "forced vital capacity," or FVC).
  • How quickly the person can breathe out (the "forced expiratory volume in one second," or FEV1).

In COPD, FEV1 is lower than normal, and FVC is often higher than normal.

Doctors often take a chest X-ray or CT scan in people who complain of shortness of breath. Although this is reasonable, to diagnose COPD it's also necessary to do the pulmonary function testing.

Another test doctors may use is a special blood draw called an ABG (arterial blood gas). People with COPD usually have higher-than-normal levels of carbon dioxide in the blood. In more advanced COPD, they also develop lower-than-normal levels of oxygen in the blood. The ABG draw measures these levels to help determine the disease's severity. (An oxygen saturation meter, which clips onto the finger, measures oxygen but doesn't provide information about carbon dioxide levels.)


Community Answers

A fellow caregiver answered...

To whom it may concern: what is your oxygen level suppose to be? I used to smoke for 15 years and I quite now its been 2 years and I got sick and went to the doctor he said my oxygen level was 60 and he said that was to low.So now its back up to were its suppose to be I had walking ammonia so now I still have problems breathing it comes and it goes. I thought when I quite smoking it would get better.

Bradleau answered...

Most people do well with a saturation of 87 or higher. I have noted smokers tend to have higher oxygen sats than non smokers. Smokers say that they inhale deeper, therefore use most of their lungs. No fact on that. But if you were 60 on your sats, I am surprised you were able to even sit up. Sometimes by the time you quit smoking, the damage is done. My husband smoked for years, and finally quit when he had two month long chest colds that he could not shake. He still gets more frequent, and worse chest colds than I do. I seldom get sick by the way. He quit 18 yrs ago. But now I am the one with reduced lung function. My sats are OK, but I get short of breath really easy and feel like I am smothering. A lung function test was done,as well as reviewing Xrays. Nothing can be done. Fibrosing of the lung tissue due to complications from surgery/infection.

Pearlygates answered...

FOR THE SAKE OF EVERYONE, I truly wish there was a sure fire way to quit smoking, as easy as it was to quit drinking. the patches, gum, even chantix wouldn't help. However it is no ones fault, but our own, we took on this nasty, disgusting habit as it is, an now do not have the willpower to break it, even though we know it will be the primary cause of our death, sad, isn't it.

Bewell answered...

Seems like we like to play life to the limit, sad part is time wins out, it's still here, but we aren't. So when or if one sees this or cares about living healthy, time becomes the good memories of our life.

Gus1 answered...

I quit smoking over a year ago and feel so much better. I just wish I had done it years ago. My advice is never quit trying.

"the one who knows" answered...

The first thing a person who smoke has to do is have his mind made up that he wont to stop smoking, for one reason or another, because he know's its bad for his Health and he know he will have trouble further in life, and hopely its not too late. I realize that fifty one years ago, after smoking two and a half pack a day, and I quit cold turkey with a carton in the house and I refuse to get one, I put them in the frezer and I often refer to it that I froze my taste out of my system and if so I have no problem with that. Hopell I can give you smokers the secrets to stop smoking And that is "NEVER TAKE THE NEXT ONE" And I have no dout you will be a winner, happy with yourself and everybody will be happy with you. I just dispise smelling the order on someone's Breath and their Clothing. I just wish everybody could stop Smoking. I did so can you, no such word can't. Good Luck all you Smokers, and Try my no smoking method.