Spirometry
Spirometry is a widely used pulmonary function test that measures lung capacity and efficiency, playing a crucial role in diagnosing various respiratory conditions, including asthma, emphysema, cystic fibrosis, and chronic obstructive pulmonary disease (COPD). The test employs a device called a spirometer, which records the amount of air a person can inhale and exhale. Historically, the interest in measuring lung function dates back to ancient times, with significant advancements made over the centuries to improve testing methods.
During a spirometry test, patients typically perform a series of breathing patterns while connected to the spirometer, providing valuable data for healthcare professionals. Key measurements obtained from the test include forced vital capacity (FVC) and forced expiratory volume (FEV), which help assess overall lung health and functionality. Spirometry is generally a quick, painless, and noninvasive procedure, often conducted in a doctor's office, particularly for individuals over the age of forty-five or those with a history of smoking or respiratory issues. Preparation for the test includes avoiding heavy meals and smoking for several hours prior to ensure accurate results. Even with normal spirometry results, further testing may be necessary to rule out specific conditions, making this an essential tool in respiratory health evaluation.
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Spirometry
Spirometry is the most commonly used pulmonary function test, done to measure pulmonary (lung) capacity and efficiency. It helps medical professionals diagnose various pulmonary conditions, including emphysema, asthma, cystic fibrosis, and chronic obstructive pulmonary disease (COPD). A spirometer—from the Latin word spirare, meaning “to breathe”—is the most common instrument used in spirometry testing.
Overview
People have been interested in measuring lung capacity and air flow for centuries. The earliest recorded instance is a volumetric analysis of breath output conducted by ancient Roman philosopher and physician Claudius Galenus, commonly known as Galen of Pergamon. Since that time, scientists have modified and immeasurably improved testing techniques and medical technology.
Modern-day spirometry tests measure the volume of air an individual can inhale and exhale. The results allow doctors to diagnose various pulmonary diseases and conditions, in addition to assessing such things as the patient’s overall lung health, whether a previously diagnosed lung condition is improving or worsening, or whether the patient’s lungs are functioning at a level that will allow for lung surgery. Spirometry is most commonly performed on individuals who are over the age of forty-five, are recent or former smokers, have a persistent or productive cough, or have previously been treated for a lung condition.
Spirometry is a painless and noninvasive test that can be performed quickly in a doctor’s office. The machine used to perform the test is called a spirometer, and the results are often printed on a chart called a spirogram. While taking the test, patients remain seated, wear a nose clip, and breathe through a tightly fitting tube connected to the machine.
The two most common measurements taken with spirometry are forced vital capacity (FVC), which is the amount of air a patient can completely exhale, and forced expiratory volume (FEV), which is the amount of air a patient can exhale in a designated time period, usually between 0.5 and 3 seconds. Taking the values from these and several other spirometry tests allows health-care workers to assess the patient’s lung function.
Testing primarily involves the patient being asked to perform one or several breathing patterns, including inhaling and exhaling as quickly as possible; taking in a slow, deep breath and exhaling as forcefully as possible; breathing quietly and normally; and inhaling a medicine before performing one or several patterns again. Patients are usually instructed to refrain from eating a heavy meal or smoking for four to six hours prior to the test. To achieve the most accurate test results, it is essential for patients to follow all instructions exactly as they are given. Even if spirometry tests produce normal results, a patient’s doctor may require additional testing to rule out conditions such as asthma.
Bibliography
Barreiro, Timothy J., and Irene Perillo. “An Approach to Interpreting Spirometry.” American Family Physician 69.5 (2004): 1107–15. Print.
Bonner, Rachel, et al. “Applicability of the Global Lung Function Spirometry Equations in Contemporary Multiethnic Children.” American Journal of Respiratory and Critical Care Medicine 188.4 (2013): 515–16. Print.
Currie, Graeme P. ABC of COPD. 2nd ed. Oxford: Blackwell-Wiley, 2011. Print.
George, Ronald B., et al., eds. Chest Medicine: Essentials of Pulmonary and Critical Care Medicine. 5th ed. Philadelphia: Lippincott, 2005. Print
Johns, David P., and Rob Pierce. Pocket Guide to Spirometry. 3rd ed. New York: McGraw, 2011. Print.
Patra, K. P. “Spirometry.” Pediatrics in Review 33.10 (2012): 469–72. Print.
Pickover, Clifford A. The Medical Book: From Witch Doctors to Robot Surgeons, 250 Milestones in the History of Medicine. New York: Sterling, 2012. Print.
Wanger, Jack. Pulmonary Function Testing: A Practical Approach. 3rd ed. Burlington: Jones, 2012. Print.
Weiss, Pnina. “Exercise-Induced Bronchoconstriction in Children and Adolescents.” Journal of Asthma and Allergy Educators 2.5 (2011): 246–52. Print.