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Pulmonary Function Test
Pulmonary function tests are designed to measure how well the lungs take in and release air and how well they move gases such as oxygen from the atmosphere into the body's circulation.
In a spirometry test, you breathe into a mouthpiece that is connected to an instrument called a spirometer. The spirometer records the amount and the rate of air that is breathed in and out over a period of time. There are also tests to measure lung volume and diffusion capacity. This shows how effectively gas travels from the lungs into the blood.
Pulmonary function tests are used to diagnose certain types of lung disease (especially asthma, bronchitis and emphysema), shortness of breath and the effects of exposure to contaminants. They can also help to assess the effect of various medications and to measure progress in disease treatment.
Bronchial Challenge Test
The bronchial challenge test uses histamine or methacholine to determine if an individual has hyper-responsive airways. You are asked to inhale gradually increasing concentrations of the substance while pulmonary function is monitored. Bronchial asthma can be diagnosed when a patient develops the clinical manifestations of bronchial reactivity: wheezing, cough, tachypnea, and dyspnea. The test is used to plan and assess different modes of treatment.
Pulmonary Stress Test
A pulmonary exercise stress test is used to determine the cause of shortness of breath, measure exercise capacity or to obtain further information after a pulmonary function test. During the test, you are asked to walk on a treadmill or ride a stationary bicycle. Small pads (electrodes) are placed on the body to monitor the heart and you wear a face mask and breathe through a mouthpiece.
Heart rate, breathing, and blood pressure are monitored throughout the text and you will exercise as long as possible.
The six-minute walk test is used at the start of a pulmonary rehabilitation program and/or in the evaluation of lung transplant. The results of the test are helpful in setting up an individualized exercise program or determining the need for supplemental home oxygen.
The object of this test is to walk back and forth for as far as possible for six minutes on a flat surface, such as a hallway. If you become exhausted and out of breath and you are permitted to slow down, stop and rest as necessary.
You will be asked, before and after walking, to rate your degree of breathlessness and the level of difficulty, discomfort, labored breathing and fatigue. Blood pressure, heart rate, respiratory rate and oxygen saturation will be checked before, during and after the test.
Arterial Blood Gas (ABG)
An arterial blood gas (ABG) test measures the acidity (pH) and the levels of oxygen and carbon dioxide in the blood from an artery. This test can determine how well your lungs are able to move oxygen into the blood and remove carbon dioxide from the blood. An ABG measures levels of oxygen and carbon dioxide before they enter body tissues.
An arterial blood gas (ABG) test is done to:
- Check for severe breathing problems in lung diseases, such as asthmas, cystic fibrosis or chronic obstructive pulmonary disease.
- See how well treatment for lung disease is working.
- Find out if you need extra oxygen or help with breathing (mechanical ventilation).
- Find out if you are receiving the right amount of oxygen when you are using oxygen in the hospital.
- Measure the acid-base level in the blood of people who have heart failure, kidney failure, uncontrolled diabetes, sleep disorders, severe infections, or after a drug overdose.
Sputum induction is a procedure in which a sample of secretions form the lower respiratory tract is collected, usually for patients who are unable to cough or do not produce adequate sputum. It is done to assess and diagnose various respiratory disorders, such as lung-cell abnormalities and infections like tuberculosis, staff and strep infections.
Sputum for analysis can be obtained either spontaneously or by using hypertonic saline for patients who don’t have a productive cough. You will be asked to cough and the sputum that comes out is collected and analyzed.
Aerosol therapy delivers medications, humidity, or both to the surface of the breathing tubes and lungs by breaking down the medication into a very fine mist so that it can be easily and effectively inhaled with the use of a nebulizer. The most common type of medication used in aerosol therapy is called a bronchodilator (e.g. Albuterol), which may relieve spasms of the bronchial muscles, reduce swelling of the mucous membranes, help to liquify bronchial secretions so that they are more easily removed, humidify the respiratory tract and administer antibiotics locally by depositing them in the respiratory tract.
Most aerosol treatments are taken three to four times a day for approximately ten minutes.
Bronchial Hygiene Therapy
Bronchial hygiene therapy consists of a variety of non-invasive techniques to improve gas exchange by helping to mobilize and remove secretions. It is especially helpful during episodes of acute secretion clearance problems such as severe pneumonia, respiratory failure, acute lobar atelectasis, cystic fibrosis, bronchiectasis and chronic bronchitis when large volumes of secretions become problematic.
For more information or to make an appointment you can reach The Bolduc Family Outpatient Center at 443-718-3000.