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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↗

PubMed2005

Peripheral inflammation in patients with asthmatic symptoms but normal lung function.

Some patients with asthmatic symptoms and eosinophilic airway inflammation have normal lung function and thus do not meet the current diagnostic criteria of asthma. Exhaled nitric oxide (NO) measurement at multiple exhalation flow rates can be used to assess alveolar and bronchial NO output and inflammation. We tested whether alveolar or bronchial NO output is increased in subjects having asthmatic symptoms but normal lung function. Exhaled NO concentration was measured at three exhalation flow rates (100, 175, and 370 mL/s) to assess alveolar NO concentration and bronchial NO flux in 23 patients with asthmatic symptoms but normal lung function ("asthmatic symptoms group"), 40 patients with asthma, and 40 healthy control subjects. The asthmatic symptoms group had increased bronchial NO flux (1.7 +/- 0.3 nL/s, p = 0.016) and alveolar NO concentration (1.8 +/- 0.2 parts per billion (ppb), p = 0.010) compared with healthy controls (0.7 +/- 0.1 nL/s and 1.0 +/- 0.1 ppb, respectively). Patients with asthma had even higher bronchial NO flux (2.5 +/- 0.3 nL/s, p = 0.024) but normal alveolar NO concentration (1.1 +/- 0.2 ppb, p = 0.664). In asthmatic symptoms group, alveolar NO concentration correlated positively with blood eosinophil count and negatively with small airway function (FEF50% and FEF75%). In conclusion, patients with asthmatic symptoms but normal lung function have increased alveolar NO concentration and mildly elevated bronchial NO flux suggesting a more peripheral inflammation than in patients with asthma.

Adult↗

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↗

PubMed1977

The forced end-expiratory flow rate in chloromethyl ether workers.

Spirograms were made in 103 chemical workers, 72 of whom had been exposed for years to chloromethyl ethers to various degrees. The end-expiratory flow rate was below 60% of predicted in one-third of exposed men compared to only 3% of unexposed men. Smoking was a confounding factor. In 49 current cigarette smokers consuming less than one pack per day, the data suggested a dose-response relationship between chemical exposure and the frequency of low end-expiratory flow rate.

Bis(Chloromethyl) Ether↗

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↗

PubMed2002

Therapeutic effects of BCG vaccination in adult asthmatic patients: a randomized, controlled trial.

BACKGROUND: Bacille Calmette-Guérin (BCG) vaccination in humans induces Th1 immune responses. Th1 and Th2 cells are reciprocally regulated. OBJECTIVE: To examine whether BCG vaccination of adult patients with asthma, a Th2-associated allergic disease, is clinically effective. METHODS: Forty-three moderate-to-severe asthma patients were randomly assigned into groups that received percutaneous injection of 58.2 x 10(7) CFUs BCG (n = 22) or placebo (n = 21) in a double-blinded fashion, on the first day of a 12-week treatment period. Medications were adjusted every 4 weeks to maintain optimal asthma control. Spirometric measurements were performed before treatment and at weeks 4, 8, and 12 after vaccination. The daily peak expiratory flow rate values, asthma symptoms, and medications were also recorded. Tuberculin skin tests, and sputum inflammatory cell and cytokine analyses were carried out before treatment and 12 weeks after vaccination. RESULTS: BCG vaccination significantly increased forced expiratory volume in 1 second and forced expiratory flow rate 25% to 75% at weeks 4, 8, and 12. Morning peak expiratory flow rate was significantly increased only during the first 4 weeks. Although the asthma symptom scores were not significantly changed, the weekly medication scores were significantly decreased. Tuberculin skin reactivities were significantly increased without significant alterations in induced sputum profiles. In contrast, medication scores and sputum eosinophils were significantly increased, and the interferon-gamma:interleukin-4 ratio in sputum was significantly decreased in the placebo group. CONCLUSIONS: BCG vaccination improved lung function and reduced medication use in adults with moderate-to-severe asthma. This amelioration was accompanied by a suppressed Th2-type immune response, suggesting that BCG vaccination might be an effective therapeutic modality against asthma.

Adult↗

PubMed1990

Ventilatory function among metal workers in Singapore.

The ventilatory function of 634 workers in small scale metal working industries was evaluated. Almost five percent (4.7%) of the workers were found to have FEV1.0/FVC ratio of less than 75%. Compared with the lung function of industrial workers reported by Zee, 10.9% were found to have low ventilatory function. Comparison of the ventilatory function obtained from the metal workers with those of occupational groups previously reported shows that the metal workers have lower FVC and FEV1.0 values. Mid and end expiratory flow rates were also measured. These measures have been shown to be very sensitive in detecting obstructions in small airways. It is recommended that future studies should be carried out to obtain ventilatory functions for the normal population. The values reported here of FEV25%-75% and FEF75%-85% would be useful for future investigations in forced expiratory flow rates.

Adult↗

PubMed1991

Normal values of spirometry and peak flow rate in Ethiopian adults and children.

Peak expiratory flow rate (PFR), forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) were measured in 650 normal Ethiopians residing in Addis Abeba and Akaki which are located at altitudes of 2500 and 2300 metres, respectively. There were a total of 540 adults and 110 children, and in both groups the sexes were equally represented. All subjects were required to respond to a questionnaire prepared in accordance with the British Medical Research Council (MRC) in order to decide on the subjects which would be included in the study. The data obtained were analysed, and based on the results, prediction formulae for PFR, FEV1 and FVC were made. These formulae were found to be in keeping with those previously reported in similar ethnic groups.

Adolescent↗

PubMed1978

BRL10833 in inhibiting exercise-induced bronchoconstriction in asthmatic children.

A double-blind controlled exercise challenge study has been performed in 16 asthmatic chlidren to show the effectiveness of BRL10833 in inhibiting exercise-induced bronchoconstriction. The children attended the respiratory laboratory on four occasions within the space of two weeks; on each occassion a routine 6-min exercise test was performed. At the first visit no drugs were given before the exercise test and all the children demonstrated abnormal exercise-induced bronchoconstriction as measured by peak expiratory flow rate (PEFR), forced expiratory volume in 1 sec (FEV1) and forced vital capacity (FVC). On the other three occasions the children were given sodium cromoglycate, BRL10833 or placebo medications before the exercise test. After sodium cromoglycate administration four children showed complete blocking and four showed partial blocking of exercise-induced bronchoconstriction. After BRL10833 four children showed complete blocking and six showed partial blocking of exercise induced bronchoconstriction. Placebo administration produced complete blocking of exercise-induced bronchoconstriction in three and partial blocking in two children. The results indicated that BRL10833 was almost as effective as sodium cromoglycate in inhibiting exercise-induced bronchoconstriction and placebo, although less effective than the two preparations, did afford protection from exercise-induced bronchoconstriction in some of the children.

Adolescent↗

PubMed1981

Influence of age on response to ipratropium and salbutamol in asthma.

We studied the differential response to inhaled salbutamol and ipratropium of 29 asthmatic patients, 18 intrinsic, 11 extrinsic, using peak expiratory flow rate (PEFR), forced expiratory volume in one second (FEV1), and forced vital capacity (FVC). Thirty minutes after a theoretically maximally bronchodilating dose of salbutamol (400 microgram) or ipratropium (80 microgram), second doses frequently caused further bronchodilatation. We suspect that second doses may reach bronchi untouched by the first inhalation. Analysis of variance showed a powerful intrinsic versus extrinsic effect, and there were clearly differences between patients in their response to treatment (patient versus drug interaction) but these differences were not removed by dividing the patients into intrinsic and extrinsic groups. Results for the group as a whole favoured salbutamol, but examination of individual results by a pattern-recognition technique showed ipratropium equally effective in eight patients and more effective in three. All patients with a definite predominant salbutamol response were less than 40 years old. The response to salbutamol declined significantly with age, whereas that to ipratropium did not. In general in patients aged less than 40 years salbutamol is the drug of choice. With advancing age, and the apparent decline of beta-adrenergic responsiveness, the initially comparatively small response to ipratropium becomes relatively more important and may predominate. In older patients ipratropium, or continued therapy with both drugs, may be preferable.

Adult↗

PubMed1988

Persisting airway obstruction in asymptomatic children with asthma with normal peak expiratory flow rates.

Twice-daily symptom scores and peak expiratory flow readings were compared with spirometric values (FEV1 and forced expiratory flow rate between 25% and 75% of FVC [FEF 25-75]) measured at 2-week intervals in assessing airway obstruction in 20 children with asthma studied during 16 weeks. Of 56 2-week periods during which symptoms were absent, peak flow was decreased in 30 (54%), FEV1 in 20 (36%), and FEF 25-75 in 37 periods (66%). Peak flow readings were normal in 13 of 70 periods (16%) in which FEV1 was decreased, and in 33 of 113 periods (29%), in which FEF 25-75 was decreased. Of 25 periods in which symptoms were absent and peak flow was normal, 19 (76%) were associated with decreased FEF 25-75. The results confirm previous studies that indicate peak flow readings are a useful addition to symptom diaries. More importantly, they demonstrate that airway obstruction may be present in a large proportion of asymptomatic children with asthma who have normal peak flow rates and suggest that frequent assessment of FEF 25-75 is required, as well as daily monitoring of symptoms and peak flow both in trials of drug therapy and for more optimal assessment of the effectiveness of therapy in clinical practice.

Adolescent↗

PubMedDate not supplied

Variability of pulmonary function tests in stable corticosteroid dependent asthma patients.

We studied 24 corticosteroid dependent asthmatic patients over a period of 10 months to establish a baseline for future therapeutic trials with corticosteroid sparing agents. Clinical symptoms, steroid dose, peak expiratory flow rate (PF), forced expiratory volume in 1 second (FEV1), and forced vital capacity (FVC) were recorded at clinic visits. Correlation was sought between PF and FEV1, steroid dose versus PF and symptom severity, and PF versus time and symptoms. There was considerable weekly variability of PF and FEV1. However, when viewed over almost a year, 54% had no significant change in PF. 29% actually worsened and 17% improved. The data suggest that to assess the effect of a steroid-sparing agent accurately, one must first establish a reliable baseline over several months to eliminate weekly variability. The current trend of obtaining a baseline over a 1 to 2 month interval is inadequate in this study population. We also found that neither patient assessment of severity of symptoms nor corticosteroid dosage correlate with objective spirometric measurements.

Adult↗

PubMed1996

[A study on peak expiratory flow monitoring maneuver as compared to forced expiratory flow maneuver].

In this study, we tried to clarify the characteristics of peak expiratory flow (PEF) measurement maneuver as a tool of daily monitoring severity of asthma in accordance with peak expiratory flow rate (PEFR) of forced expiratory maneuver. PEF did not differ when measured either in the standing or sitting position. However, obese individuals may have higher PEF when measured in the standing position and subjects with emphysematous change may have higher PEF when measured in the sitting than in the standing position. PEF did not differ when measured either with or without nose clip. Expiration time and volume in PEF measurement requires only one fifth and a half of that of forced expiratory flow volume measurement, respectively. In 36% of asthmatic patients in whom PEF is measured daily, PEF measurements were thought to be measured after inspiring at about 90% of forced vital capacity. Although PEF is a well tolerated useful clinical parameter in the management of bronchial asthma, it has different characteristics from peak expiratory flow rate (PEFR) of forced expiratory volume measurement.

Adult↗

PubMed1993

The bronchodilator effect of Garcinia Kola.

This work investigated the bronchodilator effect of Garcinia Kola (Bitter Kola) in normal Nigerians. Nineteen undergraduate male students (17-25 years) were used for the study which involved the consumption of Garcinia Kola (15 grammes per subject) and the measurement of peak expiratory flow rate (PEFR), forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) at intervals of 30 minutes up to a maximum of 90 minutes. Each subject served as his own control. There was time-dependent increases in the measured parameters. However, only the PEFR showed significant (p < 0.05) increase and this was observed at the 60th minute. This probably shows a mild bronchodilator effect of this Kola.

Adolescent↗