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PubMedDate not supplied

Reliability of plethysmography, the single breath oxygen test, and spirometry in population studies.

Three thousand five hundred and twenty-eight residents of a census tract in Los Angeles, California underwent pulmonary function testing in a mobile laboratory (the Breathmobile). Tests included respiratory questionnaire, electronic spirometry, the single breath O2 test and body plethysmography. The reliability and sensitivity of the tests performed in the Breathmobile was measured by repeating the same tests and others on a 3% probability sample at the University of California at Los Angeles Pulmonary Function Laboratory. The reliability of the FVC and FEV1 was excellent; of the FEF 25-75% and the FEF 50-75% -- good; and of the VTG, RA and delta N2 -- reasonably good. As yet the reliability of the closing volume fraction is inadequate in our study. Grouping by individual reported symptom complexes identified different groups of people. The questionnaire and the forced expiratory flow rates identified the most people as having decreased respiratory function. Selection of the best breath or average of the two best breaths affected results of spirometry very little.

Adolescent↗

PubMed1980

Lung function in young adults: evidence for differences in the chronological age at which various functions start to decline.

In order to gather prospective information on the chronological age at which lung functions start to decline, follow-up measurements were carried out on 38 young adults (30 men and eight women) whose respiratory and cardiac function had been studied previously in the course of a survey of high school students. In the 15 subjects who had reached adult height at the time of the first study, only the vital capacity showed no change between studies, while forced expiratory flow rates (FEV1, MMEF), transfer factor (TLCO) and alveolar volume (VA) all decreased. By contrast, in the 23 subjects who had grown in stature since the previous tests, there was an increase in the slow and forced vital capacity, no consistent change in FEV1 and MMEF, and a decrease in TLCO. The findings are consistent with the view that the age-related decline does not start at the same chronological age for all lung functions, and suggest that structural changes associated with biological "aging" affect some functions before others. The results also illustrate the inadequacy of predicting values for early adulthood by backward extrapolation from later decades or forward extrapolation from the teens, and underline the need for comprehensive studies to elucidate the pattern of change which accompanies growth, maturation, and early adulthood.

Adult↗

PubMed1982

Analysis of antigen-induced changes in pulmonary mechanics in sensitized inbred rats.

An inbred line of rats was derived which develop marked and consistent dyspnea following sensitization and then exposure to aerosolized antigen. This pulmonary response was investigated in detail by determining forced pulmonary mechanics to derive respiratory rate, peak expiratory flow rate (PEFR), forced vital capacity (FVC), forced expiratory volume in 0.1 s (FEV0.1), and maximal midexpiratory flow rate (MMFR). Challenging anesthetized rats for 5 min with an aerosol of 3% egg albumin produced minimal change in respiratory rate, a 20% fall in PEFR, a 50% fall in FVC, and a 30% decrease in FEV0.1 and MMFR. The response could be inhibited or reversed by salbutamol (0.5 mg/kg, i.v.) and aminophylline (25 mg/kg, i.v.) administered either before or after challenge. The pulmonary changes are consistent with antigen-induced asthma in the rats. The response shows similarities to human asthma and may provide a relevant experimental model.

Albuterol↗

PubMed2003

Pulmonary function in patients with diabetes mellitus.

The present study was carried out to assess the lung functions in oral medicated and insulin administered patients with normal controls. 20 subjects were selected as the study group for oral medication (Group I), 20 subjects were selected as the study group for insulin treatment (Group II) and 40 subjects were selected as normal controls. Age group of Group I and Group II were 51.25 +/- 6.28 and 50.8 +/- 6.56 respectively and controls were age and height matched. Seventeen patients of Group I were undergoing treatment for the last 10-20 years and 20 patients in Group II were undergoing treatment for the last 30 years. Only male subjects were selected for the study. Lung function test were carried out with Spirometer (Vitallograph Compact II). A significant reduction in forced expiratory volume/forced vital capacity (FEV1/FVC%) was observed in oral pills used subjects and insulin administered subjects as compared to controls. Significant decrease in forced expiratory flow rate (FEF25-75%) in group I subjects was also observed as compared to controls. Forced mid flow time (FMFT) showed a significant increase in group II in comparison to controls. These changes clearly show the expiratory flow rates are reduced both in orally medicated and insulin administered patients. Increase in FMFT in group I may be due to the reduced respiratory ability to carry out the FVC test along with the side effects of oral medication for diabetes mellitus.

Administration, Oral↗

PubMedDate not supplied

Characterization of spirometric function in residents of three comparison communities and of three communities located near waste incinerators in North Carolina.

Waste incinerators are an increasingly common means of solid waste disposal. However, little is documented about the physical health of community members who live close to incinerators. During a 3-yr epidemiological study, spirometric lung function was tested once annually among residents from 3 communities surrounding a hazardous waste, biomedical, or municipal incinerator and among residents in 3 comparison communities. A total of 1,016 nonsmoking individuals, aged 8-80 yr, participated during at least 1 of the 3 yr of the study; 358 individuals participated all 3 yr. Daily air-quality sampling was done for 1 mo/yr in all 6 communities. The average monthly concentrations of particulate matter with diameters of 2.5 microns and less (PM2.5 [range = 14.6-31.5 micrograms/m3]) in all communities were similar during the 3 yr of study. The mean daily PM2.5 concentrations were significantly less than the U.S. Environmental Protection Agency's allowable 24-hr standard of 65 micrograms/m3. Individual incinerators contributed less than 2.5% of the areas' total PM2.5 levels. There was no difference in percent predicted forced vital capacity, forced expiratory volume in 1 sec, or forced expiratory flow rate over the middle 50% of the forced vital capacity among members of the incinerator communities, compared with nonincinerator communities, and there were no significant differences in lung function within the 3 sets of communities. There was no evidence from this study that an association existed between residence in these 3 waste incinerator areas, which met state and federal emissions regulations, and average spirometric pulmonary function of nonsmoking community members.

Adolescent↗

PubMed1995

Effect of maternal smoking during pregnancy on passive respiratory mechanics in early infancy.

We studied the effect of prenatal maternal cigarette smoking on passive expiratory mechanics in 53 healthy infants tested early in infancy (mean +/- SD, 5.1 +/- 1.5 weeks). Maternal smoking was measured by: 1) questionnaire reports of the number of cigarettes smoked per day; and 2) urine cotinine concentrations (corrected for creatinine) at each visit. Respiratory system mechanics were assessed by the single-breath occlusion-passive-flow-volume maneuver. In ten infants born to smoking mothers the time constant of the respiratory system was 23% reduced [0.34 vs. 0.44 s; 95% confidence interval (CI), -45% + 1%; P = 0.06]. This was related to an estimated 13% decrease in respiratory system compliance (4.86 vs. 5.62 mL/cmH2O; 95%CI, -33% + 6%; P = 0.18) and a 10% reduction in respiratory system resistance (0.073 vs. 0.081 cm H2O/mL/s; 95%CI, -42% + 22%; P = 0.56). Functional residual capacity (FRC), measured by helium-dilution, was also decreased by 13% (78 vs. 90 mL; 95%CI, -27% + 0.3%; P = 0.06) in smoke-exposed infants. Forced expiratory flow rates at FRC obtained by thoraco-abdominal compression were reduced by 28% in infants of smoking mothers (VFRC, 99 vs. 138 mL/s; 95%CI, -54% + 2%; P = 0.04) as reported previously in a larger sample from this population. This study was limited by small numbers of infants exposed to smoking during pregnancy and by ethnic imbalance among the smoking-exposed and unexposed groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1975

Lung function in childhood. III. Measurement of airflow resistance in healthy children.

Indices of airflow resistance have been obtained in a group of 248 healthy London schoolchildren from recordings of peak expiratory flow rate (PEFR), forced expiratory volume in 0-75 seconds (FEV 0-75) and maximum mid-expiratory flow (MMEF) and two more direct methods, airways resistance (Raw) measured plethysmographyically and total respiratory resistance (PT) by the forced oscillation technique. The normal data are presented.

Adolescent↗

PubMed1984

Suppression of ventricular ectopy with intravenous metoprolol in patients with chronic obstructive pulmonary disease.

Intravenous metoprolol, 0.2 mg/kg, was given to 11 patients with stable, partially reversible chronic obstructive pulmonary disease (COPD) and frequent ventricular ectopic depolarizations (VEDs). The frequency of VEDs during 8 h of continuous ECG recording was reduced from a mean of 214/h to 86/h (p less than .001). Four/11 patients had a greater than 90% reduction in VEDs. There were no adverse clinical effects during the period of drug administration. However, metoprolol produced small declines of 14% in the forced expiratory volume in 1 sec (FEB1) and 21% in the forced expiratory flow rate between 25% and 75% of the forced vital capacity (FVC) (FEF25-75). These data suggest that iv metoprolol is effective in reducing the frequency of VEDs in patients with COPD, although the extent of reduction in VEDs shows considerable interindividual variation. Metoprolol can be administered iv without inducing clinical bronchospasm in most patients.

Aged↗

PubMed1995

Relationship between nasal resistance and airway hyperreactivity following nasal provocation with Dermatophagoides pteronyssinus in allergic rhinitis.

To determine whether nasal allergic symptoms can cause bronchial hyperresponsiveness to methacholine, 30 subjects with allergic rhinitis (22 with allergic rhinitis and 8 with allergic asthmatic rhinitis) were studied. All subjects were skin test positive to Dermatophagoides pteronyssinus (DP) and underwent nasal allergic provocation with DP. After provocation, there was a severe nasal allergic reaction in the challenged nostril with a significant increase in nasal resistance both immediately and long (7 h) after DP exposure. There were no significant changes in the forced expiratory volume in 1 s and the forced expiratory flow rate between 25 and 75% of the forced vital capacity and in both allergic rhinitis and allergic asthmatic rhinitis patients. There was also no change in bronchial hyperresponsiveness to methacholine. The eosinophil counts, leukotriene B4, leukotriene C4 and platelet-activating factor levels in nasal discharges also showed no differences in both groups of patients. Our studies suggest that nasal provocation with limited allergen is a safe diagnostic technique. However, the relationship between nasal resistance and airway hyperreactivity is not obvious in this study. The similar concentrations of nasal inflammatory mediators in both allergic rhinitis and allergic asthmatic rhinitis indicate that bronchial hyperreactivity is not solely due to nasal drainage of inflammatory mediators.

Adolescent↗

PubMed2001

Effects of blasting fumes on exposure and short-term lung function changes in tunnel construction workers.

OBJECTIVES: This study attempts to determine the effects of exposure to blasting fumes and its influence on the lung function of tunnel workers. METHODS: Two groups of tunnel workers, one using ammonium nitrate fuel oil (ANFO) as the explosive and the other using size-sensitized emulsion (SSE), with 24 workers per group, were compared with a reference group (N=34) with low exposure. Spirometry was used to determine lung function. Personal exposure to total and respirable dust, alpha-quartz, volatile organic compounds, oil mist and vapors, formaldehyde, nitrogen dioxide, and carbon monoxide was measured. RESULTS: The ANFO workers were more exposed to all the agents than the reference group and more exposed than the SSE workers to all the agents except total dust and carbon monoxide. The SSE workers were significantly more exposed to total dust and alpha-quartz than the reference group. High peak exposures to nitrogen dioxide (up to 20 ppm) occurred for the ANFO workers in contrast to the SSE workers, whose exposure did not exceed 2 ppm. The lung function of the ANFO workers significantly decreased by 3% for forced vital capacity, 7% for forced expiratory volume in 1 second, and 8% for forced expiratory flow rate from 25% to 75% of the forced vital capacity over the 11-day period. The changes were reversible. There were no significant changes among the SSE workers and the outdoor workers. The ANFO workers had a significant decrease in FEV1.0 when compared with both the SSE and outdoor workers. CONCLUSIONS: Tunnel workers using ANFO explosive show a temporary reduction in lung function, whereas those using SSE do not. The most likely explanation for the observed changes is peak exposures to nitrogen dioxide.

Adult↗

PubMed1987

Genetic factors in nonspecific bronchial hyperreactivity. An epidemiologic study.

We tested bronchial reactivity to carbachol in 50 asthmatics, healthy parents of 40 asthmatic children, and 70 healthy subjects with no personal or family history of asthma. Stepped doses of carbachol (0.1%) aerosol were given until a 50% drop in forced expiratory flow rate from 25% to 75% was observed, or until the subject had inhaled 80 of his or her own vital-capacity equivalent volumes of the aerosol. The area under the dose-response curve was computed. Histograms of the carbachol reactivity showed a bimodal distribution: 10% of normal subjects and 50% of nonasthmatic parents had values in the asthmatic range. In 85% of parent couples at least one of the two parents had bronchial reactivity without being asthmatic. Our findings suggest that bronchial reactivity to a cholinergic bronchoconstrictor indicates an autosomal-dominant pattern of inheritance.

Adolescent↗

PubMed2001

Pulmonary function tests in beta thalassemia.

To study pulmonary function tests (PFT) in multiple transfusion recipient thalassemics, PFTs were done for 30 thalassemics and 20 matched controls. Confirmed cases of thalassemia on regular transfusion therapy were the subject of study. Apart from history and physical examination of the thalassemics, serum ferritin estimation and spirometry were done. Parameters studied included lung volumes--functional residual capacity (FRC), forced vital capacity (FVC), residual volume (RV) and total lung capacity (TLC); and flow rates--forced expiratory volume in one second (FEV1), forced expiratory volume in 1 second/forced vital capacity (FEV1/FVC), peak expiratory flow 25-75 (PEF 25-75%) and peak expiratory flow rate (PEFR). Single breath carbon monoxide diffusing capacity (DLco) and arterial blood gas (ABG) were also analysed. The mean height and weight of thalassemics were below that of age matched controls. A restrictive abnormality in PFT was found in 86.6% cases. These patients were found to have a decrease in all the lung volumes namely FVC, FRC, RV and TLC with a proportional decrease in the flow rates, FEV1, PEF 25-75% and PEF with a normal (> 0.75) FEV1/FVC ratio. DLco was decreased in all the patients with restrictive lung disease and fall in DLco showed a good correlation (r = 0.7, P < .001) with the severity of restrictive disease suggesting that some intrapulmonary pathology is likely to be responsible for the restrictive pattern. None of the cases had an obstructive or mixed pattern of pulmonary dysfunction. No correlation was found between severity of restrictive disease and the serum ferritin levels. A negative correlation with degree of hepatosplenomegaly was found. No correlation was found between severity of the defect and age, number of blood transfusions received and hemoglobin at the time of doing the test. To conclude, restrictive lung disease is the predominant abnormality in multi-transfused thalassemics, which is probably due to pulmonary parenchymal pathology. The abnormality of PFTs is not directly related to iron overload.

Adolescent↗

PubMed1993

Lung function, respiratory illness, and passive smoking in British primary school children.

BACKGROUND: Many studies have reported a significant association between parents' smoking and reduced lung function in their children, but often the association has been found to be significant only in relation to maternal smoking. There have been few epidemiological studies on this topic in Britain. METHODS: Spirometry, in 2756 children aged 6.50-11.99 years, was carried out in a representative sample of English children, an inner city and ethnic minority sample, and a Scottish sample. Forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and forced expiratory flow rates of 25-75% and 75-85% (FEF25-75 and FEF75-85) were measured and standardised scores obtained separately for the English representative sample, the Scottish sample and subgroups in the inner city sample, white and Afro-Caribbean children and those originating from the Indian subcontinent. Multiple regression analyses were used to assess associations of FVC, FEV1, FEF25-75 and FEF75-85 with the passive smoking and respiratory illness, with adjustment for a large number of potential confounders. Passive smoking was defined in terms of reported number of cigarettes smoked at home by each parent. The respiratory symptoms and illnesses assessed were wheeze, asthma and bronchitis attacks, cough in the morning, and cough at any other time as reported by parents. RESULTS: Maternal smoking, but not paternal smoking, was associated with reduced FEF25-75 and FEF75-85 in boys. No association was found between passive smoking and lung function in girls, but in an analysis including both sexes the interaction of sex and parental smoking on lung function was not significant. With few exceptions, FEV1, FEF25-75 and FEF75-85 were reduced in children with wheeze and asthma attacks. CONCLUSIONS: The effect of passive smoking may depend on the close contact of a parent with a susceptible child as only maternal smoking in boys was significantly associated with impaired lung function. However, this explanation remains unsubstantiated. A parent's report of wheeze and asthma attacks in the child is reflected in reduced lung function.

Child↗

PubMed2004

Airway obstruction in rheumatoid arthritis: CT manifestations, correlated with pulmonary function testing.

In the present study, the signs of airflow obstruction on inspiratory and expiratory CT scans in 45 patients with rheumatoid arthritis were investigated. Radiologic findings were evaluated and correlated with the clinical data, which included rheumatoid factors and pulmonary function tests results. A lung biopsy was performed in five patients. The pattern of CT findings was as follows: infiltrative (n=15), obstructive (n=12), mixed (infiltrative and obstructive; n=10), other complicating diseases (n=7), and normal (n=1). The rheumatologic factor between patients with bronchial wall thickenings and patients without thickenings was significantly different (p=0.009). The forced expiratory flow rate between 25% and 75% of the vital capacity (FEF(25-75%)) was significantly more reduced in patients with interlobular septal thickenings than in patients without these thickenings. The patients with mosaic attenuation had significantly lower mean values of FEF(25-75% ) (p=0.001) and a lower peak expiratory flow (p=0.003) than patients without mosaic attenuation. On expiratory scans, the mean air-trapping score was 21%. These air-trapping scores were found to be well correlated with FEV1/FVC (r=0.230, p=0.0452), and FEF25-75% (r=-0.63, p= 0.05). It is widely known that a relatively higher percentage of mosaic attenuation with air-trapping and a good correlation between these and functional values contribute to the detection of early airway obstruction in patients with rheumatoid arthritis, and even in patients with infiltrative lung disease only.

Adolescent↗

PubMed1999

Randomized trial of inhaled fluticasone propionate in chronic stable pulmonary sarcoidosis: a pilot study.

Pulmonary sarcoidosis is a disease in which the pathological processes are distributed along lymphatic pathways, particularly those around the bronchovascular bundles. Delivery of disease-modulating drugs by the inhaled route is therefore an attractive option. The aim of this study was to determine the efficacy of inhaled fluticasone propionate 2 mg x day(-1) in adults with stable pulmonary sarcoidosis. Forty-four adult patients (22 from each centre) were enrolled from outpatient clinics in two London teaching hospitals in a two centre, double-blind, randomized, placebo-controlled trial. Primary end points were home recordings of peak expiratory flow rate (PEFR), forced expiratory volume in one second (FEV1), and forced vital capacity (FVC). Secondary end points were symptom scores, use of rescue bronchodilator medication, and clinic values for PEFR, FEV1, FVC, forced mid-expiratory flow (FEF25-75%), diffusion capacity of the lung for carbon monoxide (DL,CO), and total lung capacity (TLC). Symptom scores of cough, breathlessness and wheeze were lower in the active treatment group, but this did not reach statistical significance, and a general health perception assessment (Short Form (SF)-36) showed a difference between active and placebo treatment. No significant differences were found between the two groups in any physiological outcome measure. No new adverse reactions were detected. The results of this pilot study do not show an objective benefit of inhaled fluticasone propionate in pulmonary sarcoidosis where the disease is stable and is controlled without the use of inhaled corticosteroids.

Administration, Inhalation↗

PubMed1991

Evaluation of the onset and duration of response to cold air inhalation challenge in cynomolgus monkeys (Macaca fascicularis).

Cold air inhalation challenge (CAIC) for the evaluation of bronchial reactivity has been proposed as a physical agent alternative to chemical agent challenges (methacholine or histamine), especially suitable for the occupational environment. The present investigation describes and evaluates a method for performing cold air inhalation challenge in Cynomolgus monkeys (Macaca fascicularis), a species shown to be useful in animal modeling studies of occupational asthma. Six adult male anesthetized monkeys were ventilated by changes in external pressure while breathing cold air (-25 degrees C to -30 degrees C). Pulmonary function testing was performed at 10, 25, 40 and 55 min post-challenge. Significant increases (P less than 0.05) in average pulmonary flow resistance (RL) and decreases in dynamic compliance (CL dyn) were observed, with maximum impairment occurring at 25 min post-challenge, with a trend towards a return to baseline values at 55 min post-challenge. Peak expiratory flow rate (PEFR), forced expiratory volume in 0.5 s/forced vital capacity (FEV0.5/FVC) and forced expiratory flow at 50% forced vital capacity (FEF50) showed the same general pattern of reduction as seen with RL; however, these results were not statistically significant, most probably owing to individual monkey variability and the small number of monkeys (N = 6) used. A repeat challenge at 25 min after a primary challenge yielded increased RL in one monkey, suggesting that no absolute refractory period is present from CAIC. Results of these studies demonstrate that CAIC causes bronchoconstriction in monkeys and may be useful in further animal modeling studies designed to determine the asthmogenic/airway irritant potential of occupational toxicants.

Air↗

PubMed1978

The effects of fiberoptic bronchoscopy with and without atropine premedication on pulmonary function in humans.

Pulmonary function studies, including arterial blood gas analysis, were performed in 21 patients undergoing fiberoptic bronchoscopy. Eight received premedication with atropine and 13 did not. In the atropine-treated group there was no significant deterioration in pulmonary function immediately after bronchoscopy compared with baseline. Compared with the values obtained after topical lidocaine anesthesia, however, there was a decrease in peak expiratory flow rate (PEFR) (20 +/- 20%), forced expiratory volume in one second (FEV1.0) (11 +/- 12%), forced expiratory flow between 25 and 75% of vital capacity (FEF25-75) (22 +/- 16%), and forced expiratory flow at 75% of exhaled vital capacity (FEF75) (28 +/- 38%) and an increase in residual volume (RV) (16 +/- 19%). In the no-atropine group, postbronchoscopy values showed a decrease in PEFR (13 +/- 19%), forced vital capacity (FVC) (13 +/- )9%), FEV1.0 (14 +/- 16%), and oxygen partial pressure (Pa02) (11 +/- 9%) and an increase in RV (19 +/- 31%) and alveolar-arterial oxygen pressure gradient (deltaAaPO2) (91 +/- 129%) compared with baseline values. In this group also, topical lidocaine anesthesia resulted in a decrease in FVC compared with baseline. We conclude that the deleterious effect of bronchoscopy on pulmonary function is counterbalanced by the beneficial effect of atropine and that atropine is therefore a useful premedication for fiberoptic bronchoscopy.

Adolescent↗

PubMed1997

Continuous avoidance measures with or without acaricide in dust mite-allergic asthmatic children.

BACKGROUND: Improvement in the quality of life in the Western world and increased time spent indoors by children have enhanced the spread of house dust mites and increased the exposure time for sensitive children. Also, exposure to house dust mites in infancy and subsequent development of childhood asthma have been clinically linked. Recently, new acaricides have been developed. OBJECTIVE: To test the efficacy of the new acaricide (esdepallethin and piperonyl butoxide--"Acardust") combined with environmental control compared with continuous house dust mite avoidance measures. METHOD: Forty-six house dust mite-allergic, asthmatic children were evaluated for 6 months in a prospective, randomized, double-blind, and placebo-controlled study. Patients were randomly allocated to active and placebo acaricide treatment combined with avoidance measures, whereas only continuous avoidance measures were taken in the third group. Symptom score, medication usage, and peak flow measurements were recorded daily. The amount of house dust mite allergen in the dust vacuumed from the bedrooms was also measured. RESULTS: Morning and evening peak expiratory flow rates and forced expiratory volume in one second remained unchanged throughout the study period. In all groups, the symptom scores improved significantly, whereas the amount of house dust mite allergen decreased significantly at the end of the trial. CONCLUSIONS: Continuous house dust mite avoidance measures have a significant positive effect on the symptomology of children with mild or moderate asthma. "Acardust" combined with continuous house dust mite avoidance measures is not more effective than continuous house dust mite avoidance measures alone in the treatment of house dust mite-allergic, asthmatic children.

Aerosols↗