Abstract
In obstructive lung disease, the characteristic change in spirometry is a reduction in the forced expiratory volume in the first second (FEV1) with respect to the vital capacity. Moreover, the severity of the obstruction can be graded by referencing spirometric measurements to age, sex, and height predicted normal values. Spirometry, however, should be considered a medical test, and not simply a vital sign that anyone can perform. Indeed, both technical issues and tester skills can profoundly affect the results and interpretations. Properly done spirometry can guide therapies and predict outcomes, but using spirometry to screen for obstructive lung disease in asymptomatic populations can be problematic, and the effects of screening spirometry on outcomes have yet to be determined. The value of spirometry is increased when it is of good quality, is interpreted properly, and is used in high-risk populations as a case-finding rather than a screening tool.
Footnotes
- Correspondence: Neil R MacIntyre MD FAARC, Division of Pulmonary and Critical Care Medicine, Duke University Hospital, Box 3911, Durham NC 27710. E-mail: neil.macintyre{at}duke.edu.
Dr MacIntyre presented a version of this paper at the 44th Respiratory Care Journal Conference, “Respiratory Care Controversies II,” held March 13-15, 2009, in Cancún, Mexico. Dr Selecky was unable to attend the conference, so Dr MacIntyre presented both sides of the argument.
Dr MacIntyre has disclosed a relationship with CareFusion.
- Copyright © 2010 by Daedalus Enterprises
