Newly diagnosed

Alpha-1 lung disease should be suspected in people who have early onset Chronic Obstructive Pulmonary Disease (COPD); that is, in people in their forties or younger or in people with COPD who have not smoked or have smoked very little. It should also be suspected if a certain emphysema pattern shows up on a chest X-ray – basilar emphysema (emphysema in the bottom of the lungs) or a family history of emphysema. Alpha-1 should also be considered in asthma, as it’s tough to treat, particularly if the lung function doesn’t return to normal with treatment. Recurring respiratory infections might indicate a different sort of Alpha-1 lung damage known to doctors as bronchiectasis.

Aside from the tests to detect Alpha-1, several tests determine lung function. Among the most frequently used are:

Spirometry

These tests determine how much air can be breathed in and out (volume) and how rapidly the movement of air can be (flow rate), especially during exhalation. Normal or predicted values are determined through studies of people with no lung disease and who are the same height, sex, ethnic background and age as the patient.

The patient is asked to blow into a machine as deeply and forcefully as possible, and the best score of three or four attempts is recorded. Often, the patient is given a bronchodilator, and the tests are repeated about fifteen minutes later. The pre-and post-bronchodilator tests are compared to see if there has been any change. Results are recorded as actual scores and percentages when comparing normal or predicted values. The most common measures are:

Forced Expired Volume in One Second (FEV1)

This is the air that can be blown out in the first second. A lower result than expected (that is, in comparison with the reference group of people of the same sex, height, etc) may indicate problems.

Forced Vital Capacity (FVC)

This is the total amount of air that can be blown out. It is registered on the computer as a graph showing the flow volume curve or loop. The shape of this graph can help determine the type of lung disease, if any, that may be present.

Ratio of FEV1 to FVC (FEV1/FVC)

This is reported as a percentage and is determined by dividing the actual FEV1 by the actual FVC. The normal ratio ranges from 70-85% but declines with age. In obstructive diseases like Alpha-1, the ratio is usually lower than normal.

Diffusing Capacity

This test measures how efficiently the lungs, specifically the alveoli (air sacs), are taking in oxygen. For people with Alpha-1, the diffusing capacity will be lower than normal as less lung surface is available for the gas exchange.

Arterial Blood Gases

A blood sample is drawn from an artery (usually one near the wrist) to determine how well oxygen enters the blood and carbon dioxide is leaving. The levels of O2 and CO2 in the blood are tested by measuring the pressure that each of these gases exerts within the blood specimen, and the results are expressed as the partial pressure of oxygen from arterial blood or PaO2, and the partial pressure of carbon dioxide from arterial blood or PaCO2.