Pulmonary Function Test
What are pulmonary function tests?
Pulmonary function tests (PFTs) measure how well your lungs take in and exhale air and how efficiently they transfer oxygen into the blood. There are several different tests.
- Spirometry measures how well the lungs exhale (breathe out).
- Lung volume measures how well the lungs inhale (breathe in).
- Testing the diffusion capacity of carbon monoxide (DLCO) shows how efficiently the lungs transfer oxygen from the air into the bloodstream.
Why are these tests done?
Pulmonary function tests help:
- Diagnose diseases of the lung such as asthma, chronic bronchitis, and emphysema.
- Determine the cause of shortness of breath.
- Measure the effects of exposure to chemicals, coal dust and other toxins on your lung function.
- Measure the effectiveness of medicines and other treatments.
- Detect lung disease at an early stage before you have symptoms.
How do I prepare for these tests?
Eat a light meal and do not smoke for four to six hours before your test. If you have asthma, ask your health care provider if you need to stop using asthma medicine before the test.
How is the test done?
Spirometry—You breathe into a mouthpiece that is connected to an instrument called a spirometer. The spirometer measures the volume of air that you can force out of your lungs in one second after having inhaled as much as you can. You will be asked to hold the tube of a spirometer in your mouth, inhale as much air as possible, then blow out as hard as you can into the spirometer for one second. The amount of air you can force out is called your forced expiratory volume, or FEV1.
Lung volume—You breathe nitrogen or helium gas through a tube for a certain amount of time. Then the concentration of the gas in a chamber attached to the tube is measured.
Diffusion capacity—You breathe carbon monoxide for a very short time (often one breath). The concentration of carbon monoxide in the air you exhale is then measured. The difference in the amounts of carbon monoxide inhaled and exhaled shows how quickly gas can travel from your lungs into the blood.
PFTs are painless, and you will have time to rest between the different breathing measurements. The measurements may be repeated two or more times.
A pulse oximeter is a medical device that indirectly measures the oxygen saturation of a patient's blood (as opposed to measuring oxygen saturation directly through a blood sample) and changes in blood volume in the skin, producing a photoplethysmograph. It is often attached to a medical monitor so staff can see a patient's oxygenation at all times. Most monitors also display the heart rate.
A blood-oxygen monitor displays the percentage of arterial hemoglobin in the oxyhemoglobin configuration. Acceptable normal ranges are from 95 to 100 percent, although values down to 90 percent are common. For a patient breathing room air, at not far above sea level, an estimate of arterial pO2 can be made from the blood-oxygen monitor SpO2 reading.
We also perform exercise pulse oximetry for Medicare patients needing to re-qualify for their home oxygen and to evaluate a patient's oxygen levels during exercise.
We offer an in-office Coumadin clinic for those patients using Coumadin, Warfarin, Lovenox, and Fragmin. We perform a finger stick PT/INR level check as well as a consultation with an RN.
What is the prothrombin time test?
The prothrombin time, or PT, test measures the time it takes your blood to form a clot. This test is also often called protime.
The results of the prothrombin time test may vary from lab to lab, so healthcare providers use a ratio called the INR (international normalized ratio) to be able to account for the differences.
Why is this test done?
The PT/INR is usually done to measure the effect of blood-thinning medicines (anticoagulants), such as Warfarin (Coumadin).
If you have a medical condition such as atrial fibrillation or deep vein thrombosis, or have had a heart valve replaced, your blood is more likely to form clots. Clots can block blood vessels and possibly cause a heart attack or stroke. Your healthcare provider may prescribe a blood thinner to help prevent clots. It's very important to measure the effect of a blood thinner with this test. The medicine should keep the blood just thin enough to prevent clots. If the blood is too thin, you may bleed too easily.
The prothrombin time test may also be done if you have abnormal bleeding or clotting.
At the Gwinnett Pulmonary Group, we offer a number of injections and vaccines meant to keep patients healthy and well at all times. These injections include:
- Used to treat patients with severe asthma