Forced spirometry reference values for Norwegian adults: the Bronchial Obstruction in Nord-Trøndelag study

Spirometry and maximal respiratory pressures are pulmonary function parameters commonly used to evaluate respiratory function. Prediction values are available for conventional lung function devices using a standard tube or flanged type of mouthpiece connection. This equipment is not suitable for patients with facial or buccal muscle weakness, because of air leakage around the mouthpiece. A face mask was used for the portable lung function devices used in the neuromuscular department.The aim of this study was to compare the face mask and the conventional mouthpiece for the measurement of spirometry and of respiratory pressures in 22 healthy subjects.Values obtained with the conventional mouthpiece differed significantly from values obtained with the face mask. With the mask, forced vital capacity and forced expiratory volume in one second were 200 mL lower, and maximal expiratory pressure was 3.2 kPa lower than with the mouthpiece. Subsequently, new prediction values for face mask spirometry and maximal respiratory pressures were obtained from 252 other healthy subjects, from which new prediction equations were derived.It was concluded that the face mask connection to the lung function device is a valid alternative, is easy to use and is most useful to monitor changes in patients. This study confirms the importance of appropriate prediction equations, depending on subjectinstrument interfaces. Measurement of vital capacity (VC) and maximal respiratory pressures is commonly used to evaluate respiratory function and respiratory muscle strength in patients with chronic obstructive pulmonary disease or neuromuscular diseases [1][2][3]. Portable devices are useful for rapid and simple assessment of respiratory function in the office and at the bedside. Prediction values of spirometry and maximal respiratory pressures are available for portable and nonportable devices with a standard tube or a flanged type of mouthpiece connection [4][5][6][7][8]. This equipment is only suitable for subjects capable of making a good seal with their lips around the mouthpiece. However, patients with neuromuscular diseases characterised by facial or bulbar muscle weakness, e.g. amyotrophic lateral sclerosis, myasthenia gravis, myotonic dystrophy and facioscapulohumeral muscular dystrophy, often cannot effectively seal the lips around the mouthpiece, especially during forced manoeuvres such as spirometric and maximal respiratory pressure measurements [9,10]. In these cases, the conventional equipment with a tube or flanged type of mouthpiece is not adequate to evaluate respiratory muscle function. Therefore, a face mask adjusted to a portable spirometer and manometer was used to minimise air leakage in neuromuscular patients.The objective of this study was two-fold. First, possible differences in measurements between the original devices with the conventional mouthpiece and the face mask-adjusted devices were studied in healthy subjects. Secondly, a study to render new prediction equations for face mask spirometry and maximal re...

Section: Discussionsupporting

confidence: 82%

Face mask spirometry and respiratory pressures in normal subjects

Wohlgemuth¹,

Kooi²,

Hendriks³

et al. 2003

“…5). All other mean prediction equations, except those of LANGHAMMER et al [13], showed a greater decrease by age among the elderly than the present study.…”

Section: Resultscontrasting

confidence: 53%

“…The fitness of use of the present prediction equations was ascertained by comparing the goodness of fit obtained using the present equations with those obtained using both recently published sets of prediction equations [1,13,14] and those from the ECSC, applying all sets of equations to the present study population.…”

Section: Discussionmentioning

confidence: 99%

Prediction equations for normal and low lung function from the Health Survey for England

Falaschetti¹,

Laiho²,

Primatesta³

et al. 2004

159

170

The aim of this study was to derive new spirometric reference equations for the English population, using the 1995/1996 Health Survey for England, a large nationally representative cross-sectional study.The measurements used were the forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) of a sample of 6,053 "healthy" (nonsmokers with no reported diagnosis of asthma or respiratory symptoms) White people aged o16 yrs. Multiple regression analysis, with age and height as predictors, was carried out to estimate prediction equations for mean FEV1, FVC and FEV1/FVC, separately for males and females. A method based on smoothing multiple estimates of the fifth percentiles of residuals was used to derive prediction equations for the lower limit of normal lung function.The new equations fit the current English adult population considerably better than the European Coal and Steel Community equations, and the proportions of people with "low" (below the fifth percentile) lung function are closer to those expected throughout the whole adult age range (16 to w75 yrs). For the age ranges the studies share in common, the new equations give estimates close to those derived from other nonlinear equations in recent studies.It is, therefore, suggested that these newly developed prediction equations be used for the White English population in both epidemiological studies and clinical practice. Reference values, predicted for normal healthy nonsmokers, are generally used in epidemiological work as well as in clinical surveillance to determine low lung function and assess the effect of environmental exposure. A number of sets of prediction equations are currently available for different populations, with those most widely used based on relatively old studies [1][2][3][4].In 1995 and 1996, the general population Health Survey for England (HSE) had a focus on respiratory disease, and the lung function of respondents was measured. Use of European Coal and Steel Community (ECSC) reference values [4] for analysis in the published reports showed that these values were not predictive of normal lung function for the English population [5]. This poor fit for the ECSC reference values prompted the present study, to derive a new set of reference values based on the HSE 1995 and 1996 combined datasets. These newly derived reference values are presented here and compared with the ECSC and other recent reference values. MethodsThe design of the HSE, an annual nationwide household survey of the English population, has been described in detail elsewhere [6]. Briefly, members of a stratified random sample, sociodemographically representative of the English population, were invited to participate in 1995 and 1996. The mean response rate was w75% in both years, but slightly lower than average amongst males and in inner cities. Data on each respondent were collected during two visits, with identical methods used in 1995 and 1996: an interviewer9s visit, during which a questionnaire was administered and height and weight m...

“…The use of the prediction equations from the European Community for Coal and Steel (ECCS) [24] to derive the LLN might have underestimated FEV1 and FVC predicted values, as reported by other authors [36]. However, it should be pointed out that ECCS equations were derived from old data collected from a number of different studies, using different methods and from different populations [36].…”

Section: Discussionmentioning

confidence: 83%

The European Respiratory Society spirometry tent: a unique form of screening for airway obstruction

Maio¹,

Sherrill²,

MacNee³

et al. 2012

In order to raise public awareness of the importance of early detection of airway obstruction and to enable many people who had not been tested previously to have their lung function measured, the European Lung Foundation and the European Respiratory Society (ERS) organised a spirometry testing tent during the annual ERS Congresses in 2004-2009. Spirometry was performed during the ERS Congresses in volunteers; all participants answered a simple, brief questionnaire on their descriptive characteristics, smoking and asthma. Portable spirometers were freely provided by the manufacturer. Nurses and doctors from pulmonary departments of local hospitals/universities gave their service for free. Lower limit of normal (LLN) and Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria for diagnosing and grading airway obstruction were used.Of 12,448 participants in six congress cities, 10,395 (83.5%) performed acceptable spirometry (mean age 51.0¡18.4 yrs; 25.5% smokers; 5.5% asthmatic). Airway obstruction was present in 12.4% of investigated subjects according to LLN criteria and 20.3% according to GOLD criteria. Through multinomial logistic regression analysis, age, smoking habits and asthma were significant risk factors for airway obstruction. Relative risk ratio and 95% confidence interval for LLN stage I, for example, was 2.9 (2.0-4.1) for the youngest age (f19 yrs), 1.9 (1.2-3.0) for the oldest age (o80 yrs), 2.4 (2.0-2.9) for current smokers and 2.8 (2.2-3.6) for reported asthma diagnosis.In addition to being a useful advocacy tool, the spirometry tent represents an unusual occasion for early detection of airway obstruction in large numbers of city residents with an important public health perspective.