How to make sure your spirometry tests are of good quality.

Poorly performed spirometry greatly increases the risk of misinterpreting spirometry results. The most common cause of erroneous results is suboptimal patient coaching. Use exaggerated body language to demonstrate each of the 3 phases of the forced vital capacity (FVC) maneuver. The first phase of the maneuver (the maximally deep breath) is the most important and should receive the most emphasis. In the second phase (the blast) startle the patient to prompt maximum flow during the first second. In the third phase do not yell at the patient to keep blowing; instead, draw the patient's attention to the movement of the bell of the volume spirometer, the computer incentive display, or the audio tone of the flow-sensing spirometer, which shows that he or she is continuing to get some air out. Pay attention to the patient's body language as you coach him or her through the 3 phases. Facial expressions and body language are much more important than telling the patient what to do. Use the latest National Health and Nutrition Examination Survey (NHANES III) reference equations and the ratio of forced expiratory volume in the first second to forced expiratory volume in the first 6 seconds (FEV(1)/FEV(6)). Young, old, and sick patients can produce high-quality, reproducible pulmonary function test results. Grade pulmonary function test efforts with the scholastic grading system (A, B, C, D, and F). Implement a centralized spirometry quality assurance program. Test your spirometers daily. Be cautious in making corrections for body-temperature-and-pressure-saturated.