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PubMedDate not supplied

Functional assessment of allergic asthmatic children while asymptomatic.

The aim of this study was to detect the best test lung function to identify abnormalities in asthmatic children while asymptomatic. We studied 200 asthmatic children. Patients were evaluated by questionnaire to evaluate the presence of symptoms and drug consumption in the previous 3 months. Allergological evaluation by skin-prick tests and seric-specific IgE determination for relevant local inhalant allergens was made. Lung function was studied evaluating expiratory flows and measuring lung volumes by nitrogen washout technique. One hundred twenty-seven of 200 (63%) children showed functional abnormalities: 21 (10.5%) children had flow reductions, 56 (28%) children had volume modifications, and 50 (25%) children had either flow and lung volume alterations, respectively. We observed increased total lung capacity (TLC), residual volume (RV), and ratio RV/TLC values more often in patients with mild and moderate persistent asthma than in patients with intermittent asthma. No significant difference was detected considering expiratory flows. Measurements of lung volumes are an important tool to evaluate "air trapping" in asthmatic patients and this could be related to disease severity. According to the literature, our data suggest that an increase of RV, functional residual capacity RV/TLC could be the only functional airway dysfunction present in asthmatic children during asymptomatic period.

Anti-Asthmatic Agents↗
PubMedDate not supplied

Effect of lung volume reduction surgery in a rabbit model of bullous lung disease.

Clinical use of staple lung volume reduction surgery (LVRS) has proliferated for treatment of emphysema despite limited data regarding efficacy or optimal techniques. Recent studies in animal models of obstructive lung disease describe the decrease in lung compliance and increase in airway support as mechanisms of an improvement in pulmonary functions analogous to human data. We describe contrasting results in an animal model of bullous lung disease with a mixed but predominantly restrictive pattern of lung disease. Mixed restrictive and bullous lung disease was induced in 17 New Zealand white rabbits with i.v. Sephadex beads and endotracheally instilled carrageenan. Unilateral stapled lung volume reduction surgery was performed at 5 weeks postinduction of emphysema on the right lower lobe by lateral thoracotomy using a pediatric stapler. Static trans-pleural pressures were measured at 60, 40, and 20 cm3 inflation at preinduction (baseline), pre- and postoperatively, and 1 week postoperatively in anesthetized animals. Lungs were then harvested en bloc and examined histopathologically. The effects of volume reduction surgery on static lung compliance, lung conductance, and forced expiratory flows (FEF) were assessed. Five weeks after induction of lung disease, the animals had no significant change in static compliance and forced expiratory volume in 0.5 s (FEV0.5) or lung conductance compared to baseline. Immediately following LVRS, the animals showed a significant decrease in static compliance, FEV0.5, and conductance. One week postoperatively, compliance increased to approximately baseline levels along with a slight increase in FEFs and conductance toward preoperative levels. Histology examination revealed restrictive and bullous lung disease. Thus, we have demonstrated the feasibility of using an animal model for evaluation of volume reduction therapy for restrictive-obstructive lung disease. Physiologically, this model showed decrease conductance and decreased forced expiratory flows following lung volume reduction despite increased recoil. This is in contrast to increased conductance and flows seen in humans with severe emphysema following surgery and suggests that current criteria excluding patients with a significant restrictive component to their lung disease from LVRS surgery may be justified.

Animals↗
PubMed2005

Longitudinal validity of spirometers--a challenge in longitudinal studies.

QUESTION UNDER STUDY: Pulmonary function testing (PFT) in longitudinal studies involves the repeated use of spirometers over long time periods. We assess the comparability of PFT results taken under biologic field conditions using thirteen certified devices of various technology and age. Comparability of measurements across devices and over time is relevant both in clinical and epidemiological research. METHODS: Forced Vital Capacity (FVC), Forced Expiratory Volume in the first second (FEV1) and Forced Expiratory Flow 50% (FEF50) were compared before and after the data collection of the Swiss Study on Air Pollution and Lung Diseases in Adults (SAPALDIA) and the European Community Respiratory Health Survey (ECRHS) cohort studies. Three test series were conducted with 46, 50 and 56 volunteers using various combinations of spirometers to compare the eight flow-sensing spirometers (Sensormedics 2200) used in the SAPALDIA cross-sectional and follow-up, two new flow-sensing instruments (Sensormedics Vmax) and three volume displacement spirometers (two Biomedin/Baires and one Sensormedics 2400). RESULTS: The initial comparison (1999/2000) of eight Sensormedics 2200 and the follow-up comparison (2003) of the same devices revealed a maximal variation of up to 2.6% for FVC, 2.4% for FEV1 and 2.8% for FEF50 across devices with no indication of systematic differences between spirometers. Results were also reproducible between Biomedin, Sensormedics 2200 and 2400. The new generation of Sensormedics (Vmax) gave systematically lower results. CONCLUSIONS: The study demonstrates the need to conduct spirometer comparison tests with humans. For follow-up studies we strongly recommend the use of the same spirometers.

Adolescent↗
PubMed1990

Combined effect of silica dust exposure and tobacco smoking on the prevalence of respiratory impairments among gold miners.

The combined effect of underground gold mining dust with a high content of free silica and tobacco smoking on the prevalence of respiratory impairment was examined among 2209 South African gold miners and 483 nonminers. The subjects were grouped as having normal function; minimal, moderate or marked obstruction; marked obstruction with restriction; or pure restriction on the basis of their lung function profiles. Each profile group was compared with the normal group for exposure prevalences, and additive and multiplicative relative risk models were applied to test for departure from the additivity of individual effects. Departure from additivity was found to increase progressively with the severity of obstructive impairment. The results indicated that approximately 94% of the cases with the most severe respiratory impairment (N = 191) could have been prevented through the elimination of tobacco smoking. In conclusion, tobacco smoking was found to potentiate the effect of dust on respiratory impairments.

Bronchitis↗
PubMed1992

Ventilatory standards for clinically well aboriginal adults.

OBJECTIVE: To obtain reference standards for ventilatory function of clinically well Australian Aboriginal adults. DESIGN: A cross-sectional assessment of the population of a North Queensland Aboriginal community. SETTING: A specialist clinical and public health service. The measurements were made with the cooperation of the local primary health care centre. PARTICIPANTS: The 288 study subjects included over 70% of Aboriginal adults residing in an isolated Cape York community. Those with known respiratory disease, abnormal chest x-ray findings, positive loose cough sign, abnormal lung signs or inability to perform the ventilatory tests satisfactorily were excluded; 229 persons (80%) remained for analysis. Smoking was prevalent in both men (85%) and women (76%). As in most other studies producing reference values for lung function, smokers were not excluded. MAIN OUTCOME MEASURES: Age, standing height in bare feet and sitting height were recorded. Ventilatory measurements included forced expiratory volume in one second (FEV1), forced vital capacity (FVC) and maximum mid-expiratory flow (MMEF) which is also known as the forced expiratory flow (FEF 25%-75%). RESULTS: Standing height, age and sex were the major determinants of ventilatory function. Sitting height was not a good predictor. Ventilatory values differed significantly from those expected for Europeans: Aboriginal lung volumes were much smaller (by about 25%) and fell much faster with age. The age-related decrease in lung function was less in smokers. CONCLUSION: The smoking effect may reflect the operation of differential survival or other selective factors and has been noted in some other ethnic groups. Although previous studies have yielded some ventilatory function data on Aborigines, we report the first population-based reference values expected for clinically well adults. The information will be useful to clinicians and public health workers.

Adult↗
PubMed1988

Standardization of spirometry: a summary of recommendations from the American Thoracic Society. The 1987 update.

The spirometer is used to measure forced vital capacity in pulmonary, occupational, and general medicine. Results of spirometry affect decisions regarding patient treatment and disability compensation. Accurate spirometers are also required for epidemiologic studies. The recommendations of the American Thoracic Society cover equipment selection, validation, and quality control; maneuver performance recommendations; measurement procedures; and reference values and interpretation standardization.

Forced Expiratory Flow Rates↗
PubMed2000

Changes in work practice after a respiratory health survey among welders in New Zealand.

AIMS: To assess changes in work practice among eight New Zealand engineering sites, following a study of occupational respiratory symptoms in welders two years previously. METHODS: In 1996, we found that an acute decrease in lung function was more common in welders working without local exhaust ventilation. Findings were reported back to management, study participants and the media. Two years later we re-visited the eight welding sites. RESULTS: Of the eight engineering sites, two had local exhaust ventilation present in both Study 1 and Study 2, one site had installed local exhaust ventilation in part of the site since Study 1 and one site had moved to larger premises. The remaining four sites had no exhaust ventilation or change to the workplace between studies. Five welders (12.8%) used respiratory protection in both Study 1 and Study 2, seven welders (18%) used respiratory protection in Study 1 but not Study 2, four welders (10.3%) did not have respiratory protection in Study 1 but did in Study 2 and nine welders (23.1%) did not use respiratory protection at all in Study 1 or Study 2. CONCLUSION: Further effort is required to ensure that such studies lead to significant improvements in the work environment.

Air Pollutants, Occupational↗
PubMedDate not supplied

High dose inhaled fluticasone propionate improves FEV1 and results in reduction of oral glucocorticoid dose in glucocorticoid-dependent children with severe asthma.

A retrospective chart review was performed on eight pediatric patients with glucocorticoid (GC)-dependent asthma who had been switched to fluticasone propionate (FP). A significant increase was noted in average forced expiratory volume in 1 second (FEV1) and forced expiratory flow 25-75% (FEF25-75) at 6 and 12 months. Significant reductions were noted in the oral GC dose at 6 and 12 months with a reduction at 12 months of almost 16.5 mg/day or 65% of the initial oral GC dose. This study suggests that high-dose FP use in children with oral GC-dependent asthma has oral GC sparing effects while improving FEV1 and FEF25-75.

Administration, Inhalation↗
PubMedDate not supplied

[Obstructive pulmonary emphysema. Evolution of various parameters of pulmonary function and its correlation].

A follow-up study was carried on in a series of 20 patients with chronic obstructive pulmonary disease. The parameters analyzed were forced expiratory volume in the first second (FEV1), maximum voluntary ventilation (MVV), forced expiratory flow (FEF), vital capacity (VC), and diffusing capacity of lung (DL). Considering the importance of the parameter changes observed, each of these parameters were divided in three groups. The period of observation was of two and a half years in 9 patients, and between two years and seven months to four years in 11 patients. The follow-up was characterized by stability of the parameters in cases with the greatest degree of changes, and a definite deterioration of the parameter values in patients with minor degree of basal changes. It was observed an excellent correlation between FEV1 and MVV and FEF. As to CV and DL, the relationship was only good. These findings lead us to believe that MVV and FEF values can be predicted about from the FEV1 results.

Carbon Dioxide↗
PubMedDate not supplied

[Use of food additives in a multimodal treatment of disseminated pulmonary tuberculosis].

Effects have been studied of multimodality treatment on the function of external breathing in patients with disseminated pulmonary tuberculosis using food additives Trace Minerals. Positive dynamics has been recordable of changes in indices for forced lung vital capacity, minute oxygen consumption, both prior and after loading, and maximum volume speed (MVS75) before loading. The obtained data are indicative of the efficacy of using vitamin-mineral additives Trace Minerals evidenced by improvement in bronchial patency and normalization of ventilation-and-perfusion relations in patients with destructive forms of pulmonary tuberculosis.

Adult↗
PubMed2001

Effects of water immersion on pulmonary function in asthmatics.

Immersion induces air trapping in the lungs, as does asthma. Consequently, when using diving apparatus, asthmatics may face greater risk than non-asthmatics of pulmonary barotrauma (PBT) during ascent. We studied the pulmonary airflows and closing capacities (CC = closing volume + residual volume) in subjects with exercise-induced asthma (A, n = 12) and in healthy controls (C, n = 11) under four conditions: dry and immersed, both before and after exercise (treadmill running, non-immersed). Immersed, both C and A had significant and equivalent reductions in vital capacity, FEV1, FEV1/FVC, and FEF25%-75%. Post-exercise and immersed, pulmonary airflows deteriorated further in A but were better in C: FEV1 (A, 3.6 +/- 0.8 liter vs. 3.3 +/- 0.8 liter, P = 0.001; C, 3.9 +/- 0.5 liter vs. 4.1 +/- 0.6 liter, P = 0.006), FEF25-75% (A, 3.5 +/- 1.0 liter x s(-1) vs. 3.0 +/- 0.8 liter x s(-1). P < 0.05; C, 4.0 +/- 0.9 liter x s(-1) vs. 4.3 +/- 0.9 liter x s(-1), P < 0.05). Therefore, in contrast to C, A subjects had reduced pulmonary airflows during immersion after exercise. Furthermore, A subjects more often had no closing volume phase IV when immersed after exercise than C (P = 0.005). Interpreting the absence of phase IV as indicative of more air trapping in the asthmatics during immersion after exercise would be consistent with the reductions in airflow.

Adult↗
PubMed2002

Impact of particulate air pollutants on allergic diseases, allergic skin reactivity and lung function.

Elevated levels of particulate matter can exacerbate existing asthma and atopy, while evidence that it can promote the induction of atopy and asthma is limited. A cross sectional study was taken to compare the prevalence of eye, nose, ear and airway allergic symptoms, allergic skin sensitivity and lung function in 290 high school students with a history of high 24 hour average exposure to particulate matter less than 10 microm in diameter (PM10) = 170 microg/m3 versus low PM10 of 36 microg/m3 in central Bangkok. Multivariate analysis revealed an increased risk of eye and airway symptoms in groups exposed to higher PM10 levels (p = 0.003, and 0.05, respectively). Positive skin prick tests and a history of having a lawn at home were associated with nasal symptoms (p = 0.008 and 0.04, respectively). Mean FEF(25-75%) (forced expiratory flow that occurs during the middle 50% of the forced expiratory effort) was significantly lower in those who were exposed to higher PM10 levels (3.89 +/- 1 vs 4.42 +/- 0.9 l/sec, p < 0.001). A significant increase in days of school absence and medical expenses was associated with high PM10 exposure. It is concluded that chronic exposure to high PM 10 levels was significantly associated with increased prevalence of eye and airway symptoms and a decrement of FEF(25-75%) resulting in increase of school absence and medical expense.

Adolescent↗
PubMedDate not supplied

[Measurement of cytokines in patients with exercise-induced asthma treated with anti-leukotrienes].

BACKGROUND: Exercise-induced asthma is defined as the transient broncho-spasm, that occurs after 3 to 8 minutes of continuous exercise; one of two mechanisms are implicated: the first is given by a hyper-osmolar environment interchange with the warm respiratory air and the water loss, the second due to reactive hyperemia or bronchial blood vessels edema. OBJECTIVES: To determine the effectiveness and safety of Zafirlukast treatment in exercise induce asthma, and in mild and moderated persistent bronchial asthma. Evaluate the security with laboratory test IL-2, IL-4, INFg, and CD69, to determinate TH1 and Th2 cells, laboratory and thorax x-ray determinations before and after zafirlukast treatment in exercise induce asthma, plus the functional respiratory test, and assert the clinical and adverse reaction with Zafirlukast. MATERIAL AND METHODS: A open, prospective, longitudinal study. Challenge test on a treadmill for 8 minutes. Twenty patients from the Allergy Service at Lic. Adolfo López Mateos Hospital, ISSSTE, in México City, fifteen female and five males. Aged 15 to 35 years. There was a control group of ten healthy subjects with similar age and sex. The drug Zafirlukast was administered 20 mg twice a day for eight weeks, with patient's informed and signed consent. Laboratory test: Blood Cell count, transaminases, bilirubins A, G, M and E immunoglobulins thorax X-ray, electrocardiogram, functional respiratory test before and after treatment. RESULTS: Zafirlukast blocked exercise induced asthma in the early and late phases. There was a statistically significant improvement of a VEF-1 after exercise with a p > 0.001; furthermore, there was significant improvement in the mid-spiratory speed before the exercise with a p > 0.05. The mid-spiratory speed after the exercise, improved (p > 0.01). There were no collateral reactions, such as Churg-Strauss, only transitory headache in six and nauseas in two. There were no statistically significant changes in the cytokines assessment. CONCLUSIONS: There were no statistically significant changes in the cytokines assessments, in four cases the IL-4 decreased after the treatment. The anti-leukotriene improved the bronchospastic answer during the early and late phases, reducing the FEV-1, decreasing the recovering phase.

Adolescent↗
PubMed2003

[Serum and bronchoalveolar lavage fluid neopterin levels in patients with bronchial asthma].

Neopterin is an activation marker of macrophages. These cells become activated in bronchial asthma. The aim of the study was to measure serum and BALF neopterin levels in patients with bronchial asthma. The study included 15 patients with moderate, stable bronchial asthma. Serum neopterin levels were normal, while those in BALF were increased. The results of the study seem to indicate that in patients with moderate stable bronchial asthma alveolar macrophages are activated, as shown by increased levels of neopterin in BALF.

Adult↗
PubMedDate not supplied

[Respiratory function in female workers occupationally exposed to acid air pollution].

Prevalence of respiratory symptoms and ventilatory capacity were studied in 117 female workers exposed to acid fumes and aerosols in pickling industry. Similar prevalence of respiratory symptoms was recorded in three working groups: a) pickling; b) mustard making; c) packing. Significantly higher prevalences of chronic cough (p < 0.05), chest tightness, nasal catarrh and sinusitis (p < 0.01) were found in pickling workers in relation to controls. In all three exposed groups there was a high prevalence of acute symptoms during work shift. Measured FEV1, FEF50 and FEF25 were significantly decreased in comparison to predicted normal values. Pickling workers exposed for more than one year demonstrated significantly larger acute reductions during work shift than those with shorter exposure. Our data suggest that long term exposure to acid fumes and aerosols in industrial environment may cause the development of acute and/or chronic respiratory symptoms and lung function changes.

Acids↗
PubMed2006

Reactive oxygen metabolites as an index of chronic obstructive pulmonary disease severity.

AIM: The purpose of this study was to determine whether reactive oxygen metabolite species (ROMs) correlated with lung function in patients with chronic obstructive pulmonary disease (COPD) and to investigate whether ROMs could be used as an index of COPD severity. METHODS: ROMs were evaluated in plasma by a colorimetric method (d-ROM-test) in 94 patients with COPD and in 31 healthy nonsmokers subjects. Spirometry, exhaled carbon monoxide and pulse oxymetry was performed in all patients. RESULTS: Mean plasma ROMs were significantly increased (330.38 Carratelli units) in patients with COPD. There was a negative correlation of ROMs with forced expiratory volume in the first second (r= -0.275, P<0.007), with forced vital capacity (r= -0.278, P<0.007), with forced expiratory flow (r= -0.226, P<0.029) and with oxygen saturation (r= -0.315, P<0.010). In addition a positive correlation was found between the age of the patients and the oxidative stress (r= 0.366, P<0.000). CONCLUSIONS: These data indicate the presence of systemic oxidative stress in patients with COPD. The increased oxidative stress in COPD patients was concomitant with the impairment of lung function.

Adult↗