Biomaterial Database

The accuracy of a handheld portable spirometer. 1996

D A Rebuck, and N A Hanania, and A D D'Urzo, and K R Chapman

Asthma Centre, Toronto Hospital, Ontario, Canada.

BACKGROUND Objective measurement of lung function is considered essential in the management of patients with asthma and COPD. Many primary care practitioners lack the means necessary to obtain these measurements conveniently. To meet this need, electronic spirometers, offering portability, ease of operation, and timesaving readout options have been introduced. We compared the accuracy of a typical pneumotachograph-based device with a conventional volume displacement spirometer. METHODS We compared indexes of pulmonary function (FVC, FEV1, mean forced expiratory flow during the middle half of FVC, [FEF25-75%], and peak expiratory flow rate [PEFR]) measured by the handheld device with those measured by a conventional spirometer in 75 white subjects (33 men, 42 women) with a median age of 43 years (22 to 77 years) who were either healthy or were referred to the pulmonary function laboratory of a large tertiary care teaching hospital. The order of the instrument tested first was randomized and the patients were blinded to which instrument was being studied. RESULTS There was a linear relationship between instruments for all indexes measured (r = 0.97, 0.98, 0.94, 0.94 for FVC, FEV1, FEF25-75%, and PEFR, respectively, for all p < 0.001). The random error (precision) was within 5% only for FEV1. The mean of the differences between the values obtained using both instruments (the bias) +/- limits of agreement (+/- 2 SD) were 0.06 +/- 0.56 L for FVC (p = NS), 0.2 +/- 0.44 L for FEV1 (p < 0.05), 0.61 +/- 1.26 L/s for FEF25-75% (p < 0.05), and 0.44 +/- 1.9 L/s for PEFR (p < 0.05). CONCLUSIONS Our data suggest that measurements obtained using the pneumotachograph device are closely related to those obtained by volume displacement spirometry and that the handheld device may be useful in clinical practice. However, because the limits of agreement are wide and the difference between the two instrument measurements are significant for FEV1, FEF25-75%, and PEFR, the bias between them is not consistent nor is it insignificant. Therefore, the measurements made with the two types of machine cannot be used interchangeably.

UI	MeSH Term	Description	Entries
D008168	Lung	Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.	Lungs
D008173	Lung Diseases, Obstructive	Any disorder marked by obstruction of conducting airways of the lung. AIRWAY OBSTRUCTION may be acute, chronic, intermittent, or persistent.	Obstructive Lung Diseases,Obstructive Pulmonary Diseases,Lung Disease, Obstructive,Obstructive Lung Disease,Obstructive Pulmonary Disease,Pulmonary Disease, Obstructive,Pulmonary Diseases, Obstructive
D008297	Male		Males
D008450	Maximal Midexpiratory Flow Rate	Measurement of rate of airflow over the middle half of a FORCED VITAL CAPACITY determination (from the 25 percent level to the 75 percent level). Common abbreviations are MMFR and FEF 25%-75%.	Forced Expiratory Flow 025-075 Percent,FEF 25-75 Percent,Flow Rate, Maximal Midexpiratory,MMFR,25-75 Percent, FEF,25-75 Percents, FEF,FEF 25 75 Percent,FEF 25-75 Percents,Forced Expiratory Flow 025 075 Percent,Percent, FEF 25-75,Percents, FEF 25-75
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D010366	Peak Expiratory Flow Rate	Measurement of the maximum rate of airflow attained during a FORCED VITAL CAPACITY determination. Common abbreviations are PEFR and PFR.	Expiratory Peak Flow Rate,Flow Rate, Peak Expiratory,PEFR
D004582	Electronics, Medical	The research and development of ELECTRICAL EQUIPMENT AND SUPPLIES for such medical applications as diagnosis, therapy, research, anesthesia control, cardiac control, and surgery. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Medical Electronics
D004867	Equipment Design	Methods and patterns of fabricating machines and related hardware.	Design, Equipment,Device Design,Medical Device Design,Design, Medical Device,Designs, Medical Device,Device Design, Medical,Device Designs, Medical,Medical Device Designs,Design, Device,Designs, Device,Designs, Equipment,Device Designs,Equipment Designs
D005260	Female		Females
D005541	Forced Expiratory Volume	Measure of the maximum amount of air that can be expelled in a given number of seconds during a FORCED VITAL CAPACITY determination . It is usually given as FEV followed by a subscript indicating the number of seconds over which the measurement is made, although it is sometimes given as a percentage of forced vital capacity.	Forced Vital Capacity, Timed,Timed Vital Capacity,Vital Capacity, Timed,FEVt,Capacities, Timed Vital,Capacity, Timed Vital,Expiratory Volume, Forced,Expiratory Volumes, Forced,Forced Expiratory Volumes,Timed Vital Capacities,Vital Capacities, Timed,Volume, Forced Expiratory,Volumes, Forced Expiratory