Spirometry is a basic pulmonary function test that is widely used for the detection of airflow limitation. Its use will continue to grow in the medical office setting because it is useful for both diagnostic and monitoring purposes. Additionally, the assessment of airflow reversibility is a quick, safe, and useful adjunct to baseline spirometry. Many manufacturers offer various models and types of spirometers. Before purchasing, determine the needs and characteristics of the office and its staff, and then choose an appropriate device. There is no "holy grail" for selecting what instrument is best for a specific office. Rather, it requires time and effort to make a good choice. Carefully assess the instrument before purchase and, ideally, compare several instruments. Once an instrument is purchased and it arrives, carefully validate it before reporting results. Proper training of the technicians who perform the testing is perhaps the most important factor in obtaining good spirometric testing. After adequate training, it is also important to have continued competency assessments, periodic inservices, and careful review of test results. The ATS and American Association for Respiratory Care (AARC) published extensive guidelines on the performance of spirometry. These recommendations should be followed to ensure quality and reduce interlaboratory variability. Patients should be properly prepared, the instrumentation properly calibrated, and the test conducted so that there is a good start, adequate exhalation time, satisfactory end-of-test, and good reproducibility between trials.

Age Factors↗

PubMed1997

Quality assurance.

Every pulmonary function laboratory should develop and implement a quality assurance program to minimize various technical sources of variation. This article has discussed six major components. First, the education and training of the technologists in the pulmonary function laboratory is probably the most important factor in obtaining accurate and reproducible results. A college-level education with an emphasis on math and science is recommended. After an appropriate training program, continued evaluation and feedback are important. Second, instrument maintenance should be performed on a scheduled basis to reduce or prevent instrument malfunctions. Corrective maintenance, which is usually unscheduled, should be performed by knowledgeable individuals and any repairs should be documented. Third, a procedure manual is very important to any successful quality assurance program. It should contain a broad range of information including administrative issues, quality-control procedures, stepwise instructions on test performance, and infection-control policies and procedures. Fourth, the procedures should be performed using published guidelines to help minimize the effects of the many variables. Fifth, a method to quality control each test procedure should be developed. The specific method(s) will vary according to the type of instrumentation and the manufacturer. Finally, the well-run quality assurance program must properly analyze and store the data collected. Sound statistical methods should be applied and various logs and lists should be developed.

Humans↗

PubMed1991

Comparability of pulmonary function results from 13 laboratories in a metropolitan area.

UNLABELLED: We have observed that the results of pulmonary function tests obtained at one site, in general, may not be considered 'acceptable' at another site--in part because of known or suspected variability in equipment and techniques. We sought to document the presence or absence of such variability in our metropolitan area. METHODS & MATERIALS: We compared the test results from 5 trained healthy subjects (3 men and 2 women) studied in 13 Denver-area pulmonary function laboratories in a randomized order and at approximately the same time of day. RESULTS: We performed analysis of variance on commonly reported parameters and found no significant difference for FVC (p = 0.11), FEV1 (p = 0.075), FEF25-75% (p = 0.41), and FRC by helium dilution (p = 0.22). However, marked differences between certain sites could be clinically important. In addition, we found a statistically significant difference for DLCO (p less than 0.001) and TLC (p = 0.024). Six different brands of pulmonary function equipment were used by the 13 hospitals, and differences in the number of trials performed, sequence of testing (eg, FRC determinations were sometimes done first, sometimes last), and calculation of the DLCO breath-hold time. CONCLUSION: We conclude that although the FVC, FEV1, FEF25-75%, and FRC measured by helium dilution were not statistically different in healthy trained subjects in the 13 hospitals studied, clinically important differences may exist. The DLCO and TLC were statistically different. To minimize variability and improve comparability, hospitals in a given area should give consideration to adopting standardized techniques, using comparable equipment, and adopting common reference equations.

Adult↗

PubMed1989

Efficacy of a pulsed oxygen delivery device during exercise in patients with chronic respiratory disease.

The ability of a pulsed oxygen delivery system (Puritan-Bennett Companion Oxygen Saver (COS-5) to track respiratory rate during exercise and the oxygenation achieved during the exercise while oxygen was being delivered by this system was compared to that attained while oxygen was delivered continuously in six patients with chronic obstructive pulmonary disease (COPD) and six patients with idiopathic pulmonary fibrosis (IPF). The COS-5 appeared to respond appropriately at respiratory rates between 15 and 45, even when there were minimal pressure changes at the nose. There was an excellent correlation in PaO2 at equivalent flow settings during the exercise in the patients with COPD and IPF. There were six instances (in four patients) of the 31 comparisons in which the PaO2 differed by more than 5 mm Hg. The PaO2 was higher with continuous oxygen delivery on two occasions in a patient with COPD who utilized pursed-lip breathing during the exercise. The PaO2 was higher with COS-5 delivery on two occasions in a patient with IPF who was breathing at the highest respiratory rates (44 and 45/min) during the exercise.

Adult↗

PubMed1980

Bronchodilator effects of low doses of oral theophylline and terbutaline in asthmatic subjects.

The acute pulmonary and cardiovascular effects of single doses of theophylline 130 mg and terbutaline 2.5 mg administered alone and in combination were compared with placebo over a period of seven hours in 16 stable asthmatic subjects. Terbutaline 2.5 mg produced significant bronchodilatation that peaked at three hours and lasted for four to six hours. Theophylline 130 mg produced small increments in serum theophylline concentration (1.5-4.5 microgram/ml), did not produce greater bronchodilatation than placebo and did not provide additional bronchodilatation when combined with terbutaline 2.5 mg. The clinical implications of these findings with respect to the possible utility of combining low doses of theophylline with low doses of a beta-adrenergic stimulant are discussed.

Adult↗