I have emphysema. my fev is -51. what does this mean? my doctor says it is very bad.

Stop smoking!: Normal FEV-1 is 75% or more. FEV-1 under 50% not terrible! Be sure to get flu shot yearly and extended pneumonia immunization.Maximum breathing capacity is a better test of indurance and work capacity. These tests are not all that accurate or reproducible. Do you have episodes of wheezing? When and how often. Do particular environments cause wheezing? Cats? Dog? particular dust or fumes?

FEV 1: The FEV1 is the amount of air you exhale in the first second of exhalation, after a full inhalation. A typical measurement is the FEV1/FVC ration. It is normally listed as a percent. This may be what your doctor means. First it's important to determine if it is correct. Was it measured or calculated? People do feel short of breath with a number like this. Does walking bother you?

Mis-stated: FEV is the amount of air you can force out during expiration. The usual measurement is FEV1 - the amount of air you can force out in 1 second. Both numbers are always positive - it can't be negative. I suspect you may mean that your FEV1 is 51% of predicted. That is significant. I urge you to continue all treatments prescribed, maintain follow up with your lung specialist, and join a rehab group.