ArtsAutosBooksBusinessEducationEntertainmentFamilyFashionFoodGamesGenderHealthHolidaysHomeHubPagesPersonal FinancePetsPoliticsReligionSportsTechnologyTravel
  • »
  • Health»
  • Diseases, Disorders & Conditions

What Is A Spirometry Evaluation

Updated on November 20, 2011

A spirometry evaluation, also called a pulmonary function test, is the first, most basic test that physicians use to measure your lung function. If you have asthma, severe allergies, or COPD, you are probably already familiar with this test.

A spirometry evaluation effectively determines your lungs’ ability to take in, hold, and properly use the air you breathe. The test is done with a device called a spirometer, and it involves taking a deep breath, and exhaling into the spirometer as completely, and with as much force as possible.

How Is A Spirometry Test Conducted

A spirometry test is usually done with the patient standing upright. You'll be given a spirometer with a sterile tube and mouthpiece, and you may be asked to wear a nose plug to prevent air from escaping during the test.

When the technician tells you to, you will inhale deeply to completely fill your lungs with air, then exhale as forcefully as you can, and for as long as possible. At the end of the exhalation, you will inhale as sharply as you can. As you do this, the spirometer measures and records both the volume and speed of the air passing through its chamber, and several other factors. The test is usually repeated two or three times to establish an average. The spirometry test is quick and painless, and the spirometer itself can be as simple as a simple plastic tube with a gauge or meter, or as complex as a full electronic machine with computer readout.

Typical Spirometer
Typical Spirometer

Why Would I need A Spirometry Evaluation

There are several reasons that your doctor might order a spirometry test. Among them are:

  • To determine the severity of a lung disease
  • To monitor the progression of a lung disease
  • To determine whether a lung disease is restrictive (decreasing air flow) or obstructive (disrupting air flow)
  • To monitor the effectiveness of your treatment

What Does A Spirometry Exam Actually Measure

There are several values, or parameters, that a spirometry test measures. The most common is called Forced Vital Capacity (FVC). Measured in liters, FVC is the volume of air the patient can blow through the spirometer while completely emptying their lungs.

Another common parameter is Forced Expiratory Volume over 1 second (FEV1). This is also commonly measured over 2 second and 3 second durations. FVC and FEV1 results are also often combined and expressed as a ratio.

FVC, FEV1, and the FEV1/FVC ratio are the most common measurements in a spirometry evaluation, but there are several other important results which include:

Forced Expiratory Flow (FEF): A measurement of the air you exhale during the middle portion of the test.

Forced Inspiratory Flow (FIF): Similar to FEF, but this measurement is taken as you inhale.

Peak Expiratory Flow (PEF): Is the maximum velocity, measured in liters per minute, at which the air exits your lungs as you forcibly exhale.

Tidal Volume (TV): This is the total volume of air that you inhale and then exhale during normal breathing.

Total Lung Capacity (TLC): TLC is the total volume of air in your lungs.

Bronchial Challenge Test

Spirometry is sometimes used as part of a more in depth study, called a Bronchial Challenge Test. In this case, the spirometry test is done after the patient inhales a nebulized dose of methacholine or histamine, which are both broncho restrictors (narrowing the airway). Some doctors refer to this test as a Methacholine Challenge test or a Histamine Challenge test.

The goal of the Bronchial Challenge test is to determine the degree of narrowing of the airway. This helps doctors determine the proper medication and dosage for a patient's specific needs.

Sometimes the spirometry test is repeated after the patient inhales a nebulized broncodilator (opening the airway). This is called a reversibility test, and is helpful in allowing the doctor to distinguish asthma from Chronic Obstructive Pulmonary Disease (COPD).

The Bronchial Challenge test is physically demanding. In severe cases it can result in violent, uncontrolled coughing, which make it nearly impossible to complete. The Bronchial Challenge test is not usually ordered for patients with severe airway obstruction.

Spirometry Test Results Interpretation

Since normal values vary from one person to the next, spirometry test results are usually measured against an average, based upon what doctors would expect to see in people that have similar stature, age, gender and race. While there are different ranges for each of the spirometry test parameters, if your numbers are below 85% of the average set by the National Heart, Lung And Blood Institute, you will probably be referred for additional testing.

Comments

    0 of 8192 characters used
    Post Comment

    No comments yet.

    working

    This website uses cookies

    As a user in the EEA, your approval is needed on a few things. To provide a better website experience, hubpages.com uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

    For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at: "https://hubpages.com/privacy-policy#gdpr"

    Show Details
    Necessary
    HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
    LoginThis is necessary to sign in to the HubPages Service.
    Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
    AkismetThis is used to detect comment spam. (Privacy Policy)
    HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
    HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
    Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
    CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
    Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the googleapis.com or gstatic.com domains, for performance and efficiency reasons. (Privacy Policy)
    Features
    Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
    Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
    Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
    Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
    Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
    VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
    PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
    Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
    MavenThis supports the Maven widget and search functionality. (Privacy Policy)
    Marketing
    Google AdSenseThis is an ad network. (Privacy Policy)
    Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
    Index ExchangeThis is an ad network. (Privacy Policy)
    SovrnThis is an ad network. (Privacy Policy)
    Facebook AdsThis is an ad network. (Privacy Policy)
    Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
    AppNexusThis is an ad network. (Privacy Policy)
    OpenxThis is an ad network. (Privacy Policy)
    Rubicon ProjectThis is an ad network. (Privacy Policy)
    TripleLiftThis is an ad network. (Privacy Policy)
    Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
    Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
    Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
    Statistics
    Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
    ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
    Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)