Pulmonary function tests are diagnostic tests that assess respiratory capacity. They are often used to monitor lung function if the patient has a chronic illness such as asthma, cystic fibrosis, or bronchopulmonary dysplasia.
These investigations determine how much air can be stored in the lungs, how quickly it can be inhaled and exhaled, and how correctly oxygen is transferred and carbon dioxide is removed from the blood. Tests can diagnose lung disease, determine the severity of the lung problem, and determine the effectiveness of a treatment for lung dysfunction.
How much does a pulmonary function test cost?
The amount of money you are going to spend on a pulmonary function test will be influenced by a few factors such as the facility you use, your health insurance policy, the number of tests, and your doctor. In case you don’t have health insurance, you should be prepared to pay anywhere between $1,450 and more than $3,600 for a complete set of pulmonary function tests performed at a doctor’s office. In the table below you will find the average costs of different types of tests taken to evaluate pulmonary function.
|Type of Test||Average Price Reported (without insurance)|
|Full Lung Function with Reversibility Studies||
|Spirometry, Gas Transfer, and Lung Volume (Full Lung Function)||
|Spirometry and Gas Transfer||
|Pulse Oximetry – Exercise||
|Determination of Lung Volume||
|Breathing Capacity Test||
|Evaluation of Bronchospasm||
Note: You should know that these costs would be much higher if the procedure is done inside a hospital setting.
If you have health insurance, then the costs of the pulmonary test will be covered only if they are medically necessary. Most of the patients have reported that 75% to 100% of the test have been covered. However, these costs will be influenced by your health insurance coverage and you should be prepared to pay your reduced amount after your insurance company discount kicks in and your co-pays are required until you meet your annual deductible.
|Prices sourced online|
|$1,600 in Newark, NJ|
|$2,900 in Dallas, TX|
|$1,250 in Portland, OR|
|$5,400 in Naples, FL|
|$3,300 in Lexington, KY|
|$1600 in Nashville, TN|
|$4,700 in Cleveland, OH|
|$1,500 in Dallas, TX|
|$3,300 in San Diego, CA|
|$5,4000 in Jupiter, FL|
|$3,000 in Boston, MA|
Types of pulmonary function tests
Pulmonology consultation for lung volume measurement (plethysmography)
Plethysmography is a painless procedure that measures the total capacity of the lungs. During the plethysmography, you will sit in a sealed chamber, have someone insert a breathing tube into your mouth, and inhale and exhale a measured volume of air. Then a shutter will close the breathing tube and you will be asked to breathe against the resistance of the shutter. This will cause the chest volume to expand, and this increase in chest volume will slightly reduce the volume in the tight chamber. In turn, the pressure inside the box will change, and these changes will determine the total volume of the lungs.
Cardiopulmonary Exercise Testing (CPET)
Respiratory blockage may be caused by impaired lung or heart function. State-of-the-art cardiopulmonary exercise (CPET) testing allows your doctor to make this distinction on the spot.
CPET measures how the lungs, heart, and muscles react to exercise. The tests can be performed using a stationary bike or a treadmill. As you work out, the amount of air you breathe will be measured, as well as how much oxygen you need, and how quickly and efficiently your heart beats. Depending on the type of test, you may have to wear a face mask or mouthpiece and have electrodes applied to your chest to monitor your heart activity.
Diffusion Capacity Testing (DLCO)
To determine how effectively your lungs transfer oxygen from the air to the bloodstream, your doctor may order a diffusion capacity test (also called a DLCO, which means “lung diffusion capacity for carbon monoxide”).
Diffusion capacity is measured when you breathe carbon monoxide for a very short time, often just one breath. When you exhale, the concentration of carbon monoxide is measured. The difference between the amount inhaled and the amount expired allows your doctor to estimate how fast the gas (oxygen) can pass from the lungs into the blood. Reduced diffusion may indicate interstitial lung disease and fibrosis.
To prepare for DLCO, avoid heavy foods for a few hours before the test and do not smoke for at least 4 hours before the test. Your doctor may also give you more specific instructions.
The most common investigation that is done to determine the health of the lungs is spirometry. It measures lung volume and flow: how much and how fast a person can inhale and maintain the air in the lungs. During this investigation, the patient will blow into a piece that will be inserted into the oral cavity and is attached to a recording device (spirometer). The information collected by the spirometer can be printed on a graph (diagram) called a spirogram.
What can it measure
Most commonly, spirometry measures:
- forced vital capacity (FVC) – the amount of air exhaled after a deep inspiration
- forced expiratory volume (VEF) – the amount of air exhaled by force in a single breath. The amount of exhaled air can be measured in one second, two seconds, or three seconds.
- forced expiratory flow (FEF) – the forced vital capacity at either 25% or 75% of the air volume during a forced expiration following a forced inspiration.
- peak expiratory flow (PEF) – measures how fast a person can breathe. It is usually assessed along with the forced vital capacity.
- maximum voluntary ventilation (MVV) – through this test it is possible to determine which is the largest amount of air that a person can inhale and exhale in a minute.
- slow vital capacity (SVC) – measures the amount of air inhaled as deeply as possible and exhaled as slowly as possible.
- total lung capacity (TLC) – measures the amount of air in the lungs after a person breathes as deeply as possible.
- residual functional capacity (RFC) – measures the amount of air that remains in the lungs at the end of a normal expiration of air.
- residual volume (RV) – measures the amount of air in the lungs after a maximum expiration has taken place. This test may involve breathing helium or nitrogen.
- reserve expiratory volume (REV) – measures the difference between the amount of air in the lungs after a normal expiration and the amount of air after forced expiration.
Risks of a pulmonary function test
Lung function tests have little to no risk to healthy people. If a person suffers from cardiovascular disease or has lung problems, the risks of performing these investigations should be discussed with your doctor.
Pulmonary function tests can help diagnose:
- Chronic bronchitis
- Chronic obstructive pulmonary disease (COPD)
- Damaged or scarred lung tissue
- Disease caused by the breathing of asbestos fibers
- Sarcoidosis, a collection of inflammatory cells around the organs
- Lung cancer
- Thickened or enlarged airways
- Thickening or strengthening of connective tissue (scleroderma)
- Weakness of the chest wall muscles
Patient preparation before lung tests
The patient will need to talk to his or her doctor about the medications he or she is taking – they will be told by the doctor whether they should stop taking the medication on the day of the lung test or if they can take the medication as usual.
Abundant meals before testing are not recommended, as a full stomach may reduce lung capacity and the results may be affected.
It is recommended to avoid caffeine, which causes dilation of the airways.
It is also advisable for the patient to wear light clothing, perhaps even sports equipment, because molded clothing can also block breathing.