Algorithm for interpreting pulmonary function test results. Lung problems or abnormalities can be checked for change by periodic pulmonary tests. Three working groups addressed the presentation format, the reference data supporting interpretation of results, and a system for grading quality of test efforts. Theurer, do, mph, madigan army medical center, fort lewis, washington p ulmonary function tests pfts are useful for diagnosing the cause of unexplained respiratory symptoms and monitoring patients. Pulmonary function tests pft interpretation the interpretation of lung function tests involves two tasks. Pulmonary function tests pft interpretation explained. Pdf interpretation of pulmonary function tests researchgate. There are a variety of specific pulmonary function tests that may be ordered by your physician. Scanlon expands upon the tradition of excellence begun by renowned pulmonary physiologist and father of the flow. Basic spirometry interpretation pft interpretation. Aims when to do spirometry when not to do spirometry definition of terms different patterns in spirometry problems interpreting timevolume graphs. Pulmonary function testing pulmonary function testing is a group of tests that provide objective data on a patients lung function.
Pulmonary function testing pft serves many purposes in clinical practice, and in contrast to other laboratory measures, pft results are often provided with a clinical interpretation. Patients whose results are near the thresholds of abnormality are at a greatest risk of misclassification. New spirometry interpretation algorithm critical appraisal by permanent architectural changes, such as loss of alveolar attachments, that predispose airways to collapse more readily. Restriction can be defined as a reduction in total lung capacity almost invariably reflected in vital capacity as well, and the severity can be gauged quantitatively according to. There are no internetbased training programs for pft interpretation. However, spirometry with postbronchodilator testing has been successfully employed in many major populationbased surveys, both children and in adults. For interpretation of pft reports of a particular patient, one must keep in mind that there is great physiological variability in the parameters of patients with age, sex, height. A pft may be repeated as often as your doctor thinks necessary. Pfts are a series of different breathing tests performed under the guidance of a trained pulmonary function technician, physician, or nurse and are typically done in a hospital or clinic setting. Disease patterns tlc normal or increased decreased decreased, normal, or increased rv normal or increased decreased decreased, normal, or increased. Pulmonary function tests pfts are useful for diagnosing the cause of unexplained respiratory symptoms and monitoring patients with known respiratory disease.
The major limitation of pulmonary function tests is in how they are interpreted pulmonary function tests alashkar and colleagues. Practice tools 406 clinical pharmacist october 2009 vol 1 by valerie sillito,mrpharms c hronic obstructive pulmonary disease copd is a condition characterised by progressive airflow obstruction. Interpretative strategies for lung function tests american thoracic. You are encouraged to take the pretest prior to starting the. Pdf pulmonary function testing pft serves many purposes in clinical practice, and in contrast to other laboratory measures, pft results are often. Background spirometry is a powerful tool that can be used to detect, follow, and manage patients with lung disorders. The term pulmonary function test pft can mean many different things spirometry is the most commonly performed pft focus on 3 parameters. Pulmonary function tests for the generalist mayo clinic proceedings. This brochure is intended to help you understand the meaning of pulmonary function testing, commonly referred to as pfts. Pulmonary function tests pfts are useful and important methods to evaluate children.
Basic interpretation of spirometry chris crocker copd team. This pulmonary function test pft interpretation video is part of the medcram remastered series. Spirometry is essential for confirming a clinical diagnosis of copd, and provides a useful description of the severity of the disease in addition. Officebased pulmonary function testing, also known as spirometry, is a powerful tool for primary care physicians to diagnose and manage respiratory problems. Understanding pulmonary function testing alphanet canada. A reduction in the fev1fvc ratio has proven to be a reliable signal for the presence of airway obstruction and this approach towards interpreting. Some subjects with chronic asthma may not respond at all to a agonist. Training in pft interpretation has been minimal in the vast majority of pulmonary medicine fellowship programs for 2 decades. Interpretation low fev1fvc, increased tlc, low dlco obstructive pattern with hyperinflation, low dlco consistent with emphysema. Pulmonary function testing clinical respiratory diseases.
Pulmonary function testing pft made simple iowa head. Pulmonary function tests pfts for health care professionals pulmonary function tests pfts, including spirometry, lung volumes, diffusing capacity, and airway resistance, are breathing tests led by a trained pulmonary function technologist, usually done at a hospital or clinic, but increasingly done at a physicians office. Reference equations general issues interpretation of pfts is usually based on comparisons of data measured in an individual patient or subject with reference. The addition of spirometry to nhanes in 2007 marks the first year that a bronchodilator medication has ever been administered in the survey. A stepwise approach to the interpretation of pulmonary function tests. Spirometry, which means the measuring of breath, is a routinely used pulmonary function test pft that measures the amount and speed of air that a person can inhale and exhale. Spirometry spirometry is the measurement of the air mov ing in and out of the lungs during various respiratory maneuvers. Epidemiologic studies confirm that both late diagnosis and underdiagnosis of copd are commonproblems that wider. In patients with spirometric restriction a low fvc with a normal fev1fvc, a low dlco. Sputum eosinophil count further tests for jim what tests would you order to confirm asthma. Basic interpretation of spirometry docstars doctors. Gold spirometry 2010 global initiative for chronic obstructive. If pulmonary function test results are normal but the physician still suspects exercise or allergen induced asthma, bronchoprovocation e. Explain interpretation of spirometry results most guidelines recommend the use of spirometers that provide a realtime trace to help assess the quality and repeatability of blows.
Anzsrs, australian and new zealand society of respiratory science. Overall, the goal of pft interpretation is to distinguish normal from abnormal. Johnson, md, mph, tripler army medical center, honolulu, hawaii wesley m. The interpretation flow chart from the 2005 american thoracic societyeuropean respiratory society pulmonary function testing guidelines. Despite the large amount of data gathered, many questions and interpretation problems still exist. These tests must be interpreted within the context of the patients history and physical examination, though their patterns can suggest different categories of respiratory disease.
Computer interpretation of spirometry reasonably good at identifying normal spirometry the computer cannot interpret flow volume loop patterns for patients with abnormal spirometry, the computer interpretation is frequently inaccurate and can give an incorrect interpretation in more than half of cases, depending on the population of. Expiratory flow in the latter twothirds of expiration are effort independent and vary directly with elastic recoil of the lung and inversely with airway resistance. Pdf interpretation of pulmonary function tests and impulse oscillometry in clinical practice find, read and cite all the research you need on. Given the limitations of the currently available algorithm, 4 members of the primary care respiratory alliance of canada have proposed a new algorithm figure 1 where spirometric diagnostic criteria for both asthma and copd are included and consistent with current guidelines. Spirometry spirometry is a method of assessing lung. Pulmonary function testing is a group of tests that provide objective data on a patients lung function. A medical diagnosis is unlikely to be made from pfts alone. Interpretation restrictive pattern steep slope of fv curve normal fev1fvc ratio, tlc.
Basic spirometry interpretation although the fev1 was first described in 1949 by tiffeneau the basic algorithm for interpreting spirometry using the fev1fvc ratio was developed by gaensler in 1951. Spirometry is a method of assessing lung function by measuring the volume of air a patient can expel from the lungs after maximal inspiration. Introductory material about the uses of pulmonary function testing, the basic tests that can be performed in the pulmonary function testing laboratory a general approach to interpreting pulmonary function tests twelve interactive patient cases derived from actual patient data a pretest to establish the state. Approach to pulmonary function test interpretation in obstructive disease, forced expiratory volume in the first second is decreased fev1. Additional pfts, such as measurement of maximal respiratory pressures, flowvolume loops, submaximal exercise testing, and bronchoprovocation challenge, are. All regular retirement chapter meetings begin at 10. Practical and clinically relevant, hyatts interpretation of pulmonary function tests provides userfriendly coverage of all types of pulmonary function testing as it applies to a wide range of disease conditions.
A stepwise approach to the interpretation of pulmonary function tests jeremy d. What is the interpretation based on these findings. A tutorial in pulmonary function test interpretation. Interpretation of common lung interpretation of common lung. A pretest to establish the state of your knowledge with this material prior to starting the tutorial and a posttest to evaluate how much you learned by working through the cases. Dr scanlon receives royalties for sales of interpretation of pulmonary function. President, pft retiree chapter upcoming retiree chapter meetings and events. Each of these components can be accessed by clicking on the links on the left hand side of the page.
Many organizations, including the national asthma education and prevention program. Results from the test can be used to estimate lung function and aid in. Interpretation of common lunginterpretation of common. Fvc, fev1 and fev1fvc ratio followinggpp g, p yp, a simple preset algorithm, and common spirometry patterns, one can determine the presence of. The article by cary and colleagues see page 389 raises the question. One of the first questions in interpreting pulmonary function testing is the definition of what is normal. Hospitalbased pft labs in india have excellent resources, including instruments to measure dlco, body plethysmographs body boxes to measure static lung volumes tlc and. Ruiz, md, is a pediatric pulmonologist at childrens hospital of wisconsin and assistant professor of pulmonary medicine at the medical college of wisconsin. How should one interpret pulmonary function tests in the case of pure restrictive diseases, the situation is relatively straightforward. Such spirometers tend to be quite expensive and expectations that these could be used widely in poorer countries are unrealistic. American thoracic society criteria for interpreting pulmonary function tests and reflect the material covered in the primer on. Spirometry spirometry is the simplest and most widely available pulmonary function test. Reference values for spirometry and their use in test. Pft interpretation depends on the clinical context, and multiple challenges influence pft interpretation.