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PubMed1985

Increase in tracheal size with age. Implications for maximal expiratory flow.

Because mechanical properties of central airways play an important role in determining maximal expiratory flow, we examined how tracheal size and maximal expiratory flow changed with age in 50 asymptomatic men, 19 to 61 yr of age, who were lifelong nonsmokers. Cross-sectional area (X-SA) of the intrathoracic trachea was estimated from posteroanterior and lateral chest radiographs taken at full inflation. Maximal expiratory flow-volume curves and spirometry were measured by standard techniques. Tracheal X-SA averaged 2.81 cm2 (SD, 0.38) at mean age 21.1 yr and 3.22 cm2 (SD,0.41) at mean age 52.5 yr, and correlated with peak expiratory flow (PEF) (r = 0.522, p less than 0.001) and FEV1 (r = 0.437, p = less than 0.01) (both expressed as percent predicted values based on age and height). These relationships were weaker than previously described in young men. The results suggest that with increasing age, large airways lose elastic recoil, as previously described for the air spaces. Aging changes in the airways may offset the unfavorable effects of loss of lung recoil and account for the relatively good preservation of PEF and the lack of rise in airways resistance with increasing age.

Adult↗
PubMed2007

Evaluation of pulmonary function and bicycle ergometry tests in patients with Behçet's disease.

Behçet's disease (BD) has well-defined pulmonary complications, but cardiopulmonary exercise testing and the strength of the respiratory muscles have not been studied in detail. We aimed to investigate the pulmonary functions tests, inspiratory and expiratory muscle strength and endurance, cardiopulmonary exercise test response, and the relationship of these parameters in patients with BD. Forty BD patients and 20 healthy control subjects were recruited for this study. Mean age was 32.95 +/- 7.66 years for the BD group and 33.85 +/- 6.63 years for the control group with no statistically significant difference. The ratios of slight obstructive ventilatory impairment were 32.5% for the BD group. When the values of pulmonary function tests were compared, no statistically significant difference was found in FEV(1)/FVC (Forced expiratory volume during the first second/forced vital capacity), or maximal midexpiratory flow rate (all in percent) values between patient and control groups. Maximal inspiratory and expiratory pressures, peak expiratory flow rate (in percent) and maximal voluntary ventilation (in percent) values were significantly lower than those of the control group. Body's consumption of peak oxygen (VO(2peak)), oxygen consumption (milliliters per kilogram per minute), anaerobic threshold (AT), maximum exercise ventilation (VE(max)), work load values, and exercise test time in the bicycle exercise test were significantly higher in control groups than in patients with BD. The values of heart rate reserve, breathing reserve, and VE/VCO(2) at the AT of BD patients were within normal limits We conclude that respiratory and aerobic exercise may be recommended to improve respiratory muscle strength and endurance as well as the aerobic capacity and maximal ventilatory capacity in patients with BD.

Adult↗
PubMed2002

[Evaluation of systematic pulmonary function testing for asthma in children aged three to five years].

UNLABELLED: Pulmonary function testing is not usually done in the preschool child, despite the recent data showing early deterioration in airway function in asthma. METHODS: We evaluated feasibility and clinical interest of flow-volume loop by forced expiratory maneuver and measure of airway resistance by interrupter technique (interrupter resistance), before and after inhalation of salbutamol, in 75 children aged three to five years seen in the ambulatory setting for asthma. RESULTS: Feasibility rate (92%) and reproducibility rate (91%) of those techniques were good, so that 84% of the cases could be exploited (63 children of 75). We found few significant associations between clinical parameters and flow-volume loop. We found a significant association between elevated interrupter resistance at basis and night-symptoms (P = 0.03), between diminished interrupter resistance after salbutamol and exercise-symptoms (P = 0.03), symptoms in the ambulatory setting (P = 0.02) and absence of inhaled corticosteroid treatment (P = 0.046). Pulmonary function testing resulted in treatment modification in 14% of cases. CONCLUSION: Our study shows that flow-volume loop and measure of airway resistance by interrupter technique can be done with a good reproducibility in the preschool child. Interrupter resistance appears to be better correlated than flow-volume loop with usually evaluated clinical parameters.

Asthma↗
PubMed1980

Small-airways dysfunction in nonsmokers chronically exposed to tobacco smoke.

We evaluated the effect of long-term passive smoking (involuntary inhalation of tobacco smoke by nonsmokers) and long-term voluntary smoking on specific indexes of pulmonary function in 2100 middle-aged subjects. Regardless of sex, nonsmokers chronically exposed to tobacco smoke had a lower forced mid-expiratory flow rate (FEF 25 to 75 per cent) and forced end-expiratory flow rate (FEF 75 to 85 per cent) than nonsmokers not exposed (P less than 0.005). In addition, values in passive smokers were not significantly different from those in light smokers and smokers who did not inhale (P less than 0.005). When we looked at the extent to which smoke exposure is related to graded abnormality, we found that nonsmokers in smoke-free working environments have the highest scores on the spirometric tests; passive smokers, smokers who do not inhale, and light smokers score similarly and significantly lower; and heavy smokers score the lowest (P less than 0.005). We conclude that chronic exposure to tobacco smoke in the work environment is deleterious to the nonsmoker and significantly reduces small-airways function.

Carbon Dioxide↗
PubMed1981

Lung function changes by ethanol inhalation.

The acute effect of ethanol inhalation on ventilatory capacity was studied in a group of six healthy volunteers and the results were compared to those obtained after the inhalation of a saline solution. There was a significant decrease in flow rates on partial expiratory flow-volume (PEFV) curves up to 90 min after ethanol inhalation. FEV1 values did not change significantly, either after ethanol or saline aerosol. Pretreatment with atropine did not prevent the acute reductions in flow rates in comparison with the reductions without atropine. Pretreatment with disodium cromoglycate (DSCG) considerably diminished the acute reductions of flow rates caused by ethanol inhalation. These results suggest that ethanol in some persons may act, at least partly, through releasing mediators with bronchoconstrictive action.

Administration, Intranasal↗
PubMed2004

Pulmonary functions in patients with type 2 diabetes mellitus & correlation with anthropometry & microvascular complications.

BACKGROUND & OBJECTIVES: The purpose of this study was to evaluate pulmonary functions including respiratory muscle strength in patients with type 2 diabetes mellitus (T2DM) and to determine their correlations with anthropometric profile, glycaemic control, and microangiopathic diabetic complications. METHODS: Twenty nine patients with T2DM and 11 healthy control subjects were divided into the following three groups; (i) T2DM patients with any or a combination of microangiopathy(ies) (retinopathy, nephropathy, and peripheral neuropathy) (group 1, n=12); (ii) T2DM patients without any complications (group 2, n = 17); and (iii) a healthy control group (group 3, n=11). All patients were assessed with anthropometry, glycosylated haemoglobin (HbA1C), and lipid profile. Pulmonary functions were measured by spirometry. Pulmonary diffusion capacity for carbon monoxide (DLco) was measured by the steady state method. The presence of diabetic nephropathy was determined by 24 h protein excretion. RESULTS: A significant reduction of DLco was observed in group 1 (P<0.001), as compared to the other groups. There were no differences among the three groups for other pulmonary functions; forced vital capacity, forced expired volume in one second, peak expiratory flow rate, and maximal static inspiratory and expiratory pressures. Significant correlations were observed between DLco and the following parameters in group 1; HbA1c (r=0.62, P<0.05), total cholesterol level (r = -0.44, P<0.05) and creatinine clearance (r=0.42, P<0.05). INTERPRETATION & CONCLUSION: The present study shows that the impairment of pulmonary diffusion capacity for carbon monoxide was common in T2DM Asian Indian patients having microangiopathy. Pathophysiologically, it could be related to glycaemic control or dyslipidaemia. Correlation of % BF with DLCo needs to be explored further.

Adult↗
PubMed1990

[Standardization of forced spirometry. Analysis of the basal pulmonary function (PEF, FEF2575, FEF50) in a selected group of children].

This is a study of the ventilatory function (FEF2575, FEF50, PEF) by dry spirometer Vitalograph in 1,566 children of both sexes with ages ranging from 7 to 14 years; 1,156 children (73.6%) were selected as reference population. Height was the biometric parameter with the greatest correlation to the functional variables studied in both sexes, except to PEF in females. Significant differences were observed in functional variables between male and female subjects. Multiple and simple linear regression equations and percentiles tables for each sex are presented.

Adolescent↗
PubMedDate not supplied

[Optimal dynamic characteristics of a measuring unit of the pneumotachometer].

The dynamic error of the pneumotachometer may be reduced to the minimum through optimizing dynamic characteristics of its measuring unit. Such an optimization provides that the relative dynamic error of the instrument does not exceed - 5% when measuring the maximum volume flow rate of the forced expiration.

Adult↗
PubMed1996

Value of high-resolution computed tomography in routine evaluation of lung transplantation recipients during development of bronchiolitis obliterans syndrome.

BACKGROUND: Chronic rejection is a major long-term complication after lung transplantation. The purpose of our study was to evaluate the role of repeated high-resolution computed tomographic examinations in monitoring the development of bronchiolitis obliterans syndrome after lung transplantation. METHODS: A total of 126 high-resolution computed tomographic examination in 13 lung transplant recipients was analyzed. During a mean follow-up period of 23 months, bronchiolitis obliterans syndrome developed in eight of the patients. A scoring system from 0 to 10 based on the number of chronic changes on high-resolution computed tomography was developed, and the score of each patient was compared with decline in the forced expiratory volume in 1 second and maximal forced expiratory flow rate of 50% of the forced vital capacity. RESULTS: The score of chronic changes, measured at 1 year after transplantation, correlated inversely with the values of forced expiratory volume in 1 second and maximal forced expiratory flow rate at 50% of the forced vital capacity (p < 0.05). Stage I bronchiolitis obliterans syndrome was associated with scores of 4 to 6 (mean 5.0), stage 2 with scores of 6 to 9 (mean 7.0), and stage 3 with scores of 6 to 9 (mean 7.7). The sensitivity of high-resolution computed tomography was 93% and its specificity was 92% when five chronic changes were used as a cutoff level. CONCLUSIONS: The progress of chronic changes on high-resolution computed tomography occurs concurrently with the development of bronchiolitis obliterans syndrome. High-resolution computed tomography may provide additional morphologic information for noninvasive evaluation of chronic lung rejection.

Adult↗
PubMed2001

Effect of salbutamol on lung function parameters of healthy children.

UNLABELLED: In the present study, the effect of 200 microg salbutamol compared to placebo was evaluated on lung function parameters of 37 healthy children aged 7-14 years. Salbutamol or placebo were administered, using a single blind study design, and spirometry was performed before and after 10 min of inhalation. At the time of the study, all children were symptom-free and had not suffered from any respiratory infection during the previous 4 weeks. The administration of salbutamol resulted in a significant increase of mean forced expiratory volume in 1 s (111%-115%, P<0.05), maximal expiratory flow at 50% of forced vital capacity (101%-110%, P<0.05) and maximal expiratory flow at 25 % of forced vital capacity (96%-115%, P<0.05). The administration of placebo resulted in no significant change in lung function parameters. CONCLUSION: The administration of 200 microg salbutamol results in the occurrence of a small but significant bronchodilation in healthy, non-asthmatic children.

Adolescent↗
PubMed1978

The refractory period after exercise-induced asthma: its duration and relation to the severity of exercise.

A study was carried out to determine whether an episode of exercise-induced asthma (EIA) is followed by a refractory period and to assess the factors that affect it. Nine children, 9 to 14 years of age, were studied during repeated, paired exercise tests on a treadmill. Respiratory function was assessed by measuring peak expiratory flow rate before and after exercise. Changes were related to measured uptake of O2 during exercise. When paired tests were at a constant metabolic load, the severity of EIA was relatively constant in the first test of each pair, but it diminished in the second tests as the interval between tests decreased. The ability to bronchoconstrict fully was recovered within 4 hours after a test. When tests at varying metabolic loads were followed after 30 min by tests at a constant load, the severity of EIA increased in proportion to the load in the first test of each pair. In the second tests it was inversely related to that which occurred in the first tests. These results were compatible with the suggestion that the development of EIA requires the release of a stored mediator or enzyme precursor.

Adolescent↗
PubMed1976

Lung function among black and white children.

Racial differences in ventilatory lung function were evaluated in a community study of 393 children (158 blacks, 235 whites). Mean forced vital capacity was 18 per cent larger in nonsmoking white males than in nonsmoking black males, and 11 per cent larger in nonsmoking white females than in nonsmoking black females. Similar differences were observed for the 1-sec forced expiratory volume and for the maximal expiratory flow at 50 per cent of the vital capacity. However, when adjusted for lung size (on the basis of forced vital capacity), 1-sec forced expiratory volume and maximal expiratory flow at 50 per cent of the forced vital capacity were larger in the black children compared to the white children. Lung function prediction equations based on race, sex, age, height and weight are presented for healthy nonsmoking children; these allow for an evaluation of normal lung function in both black and white children.

Adolescent↗
PubMed1994

Normal values for single exhalation diffusing capacity and pulmonary capillary blood flow in sitting, supine positions, and during mild exercise.

Previous approaches to the measurements of pulmonary diffusing capacity (DL) and pulmonary capillary blood flow (QC) utilized either the rebreathing or the single inhalation technique in conjunction with radioisotope gas and mass spectrometry. In the present study, we utilized a newly developed rapid infrared analyzer in conjunction with the slow single exhalation technique on 100 healthy volunteers to establish normal values for DL and QC under sitting, supine, and exercise conditions. The exercise level was determined by a target heart rate: HRex = ([HRmax - HRrest]/3) + HRrest. Prediction equations based on regressions on age, sex, height, or weight were then computed for sitting, supine, and exercise values. We found that mean DL and QC increased by approximately 12 percent and 8 percent, respectively, from sitting to supine posture, and by approximately 30 percent and 100 percent, respectively, from sitting (rest) to mild exercise. These results provided a database for further studies in the single exhalation method in various clinical settings.

Acetylene↗
PubMed1984

The comparative beta-adrenoceptor blocking effects of penbutolol, atenolol and sustained-release metoprolol in healthy volunteers.

The effects of penbutolol (40 mg), atenolol (100 mg) and sustained-release metoprolol (metoprolol SA) (200 mg) upon heart rate (HR) and blood pressure (BP) at rest and during bicycle ergometer exercise, have been compared in 12 healthy young men using a double-blind crossover design. Measurements of each drug's effect were made before and at 3, 10 and 24 h after a single dose, and again at 24 h after the last of seven consecutive daily doses. Resting HR and systolic BP were reduced to an equivalent extent by all three drugs. During the third minute of exercise, the effects of penbutolol and atenolol upon HR and systolic BP were consistently similar and greater than those of metoprolol SA.

Adolescent↗
PubMed1983

Pafenolol, a highly selective beta 1-adrenoceptor-antagonist, in asthmatic patients: interaction with terbutaline.

Pafenolol, a new beta 1-adrenoceptor antagonist, has been shown in animals to be more selective for beta 1-adrenoceptors than metoprolol. It was studied in asthmatic patients to evaluate whether it was more selective with respect to circulatory effects and especially whether this selectivity influenced bronchial muscle tone less than metoprolol, which has been shown to have beta 1-adrenoceptor selectivity similar to that of atenolol. Intravenous pafenolol (5 mg and 7.5 mg), metoprolol (15 mg), and saline were given double-blind at random and thereafter four increasing doses of terbutaline were given intravenously to seven asthmatic patients with reproducible reversibility of airways obstruction. After the terbutaline dose-response curve was determined, terbutaline was inhaled three times in increasing doses. A separately reported exercise study in the same patients showed that 5 mg pafenolol and 15 mg metoprolol were equipotent with respect to beta 1-adrenoceptor blockade, whereas 7.5 mg pafenolol tended to increase the blockade. The reflex tachycardia on terbutaline stimulation after pafenolol was greater than after metoprolol due to less blockade of beta 2-adrenoceptors in peripheral blood vessels. The bronchial effect of pafenolol was equal to that of saline, but there was a difference between the terbutaline dose-response curves after pafenolol and metoprolol that caused a rightward shift of the dose-response curve. Thus, pafenolol was shown to be more beta 1-selective than metoprolol.

Adrenergic beta-Antagonists↗
PubMed1993

Pharmacodynamic effects of inhaled dry powder formulations of fenoterol and colforsin in asthma.

The airway and tremor response and cardiovascular and hypokalemic effects of single doses of inhalative fenoterol dry powder capsules (0.4 mg) were compared with the fenoterol metered dose inhaler (0.4 mg) and colforsin (forskolin) dry powder capsules (10.0 mg), a direct activator of the adenylate cyclase system, in 16 patients with asthma. Subjects (FEV1 < or = 60% predicted) were investigated in a randomized, double-masked, placebo-controlled, four-period, crossover trial for a 120 minute period. All active drugs caused a significant increase in specific airway conductance (p < 0.05); the order of potency (mean +/- SEM maximum increase from baseline) was fenoterol metered dose inhaler (0.51 +/- 0.06 sec-1 x kPa-1), fenoterol dry powder capsules (0.49 +/- 0.07), and colforsin dry powder capsules (0.30 +/- 0.03). A marked increase in finger tremor amplitude resulted after fenoterol metered dose inhaler only (62.93% +/- 10.21%; p < 0.05) in contrast to fenoterol dry powder capsules (15.84% +/- 4.35%; p < 0.05) and colforsin dry powder capsules (12.87% +/- 10.44%; p > 0.05). A decrease in plasma potassium was found after fenoterol (metered dose inhaler > dry powder capsules; p < 0.05). In conclusion, fenoterol dry powder capsules caused less tremor response and hypokalemic effects than the metered dose inhaler, although the bronchodilator capacity was similar. Colforsin dry powder capsules resulted in a measurable bronchodilatation in patients with asthma.

Administration, Inhalation↗
PubMed1975

Spiroergometric and telemetric investigations during the XXI International Stoke Mandeville Games 1972 in Heidelberg.

Spiroergometric and telemetric investigations were carried out on 100 paralysed athletes during the XXI International Stoke Mandeville Games in Heidelberg, 1972. The technical and organisational difficulties in carrying out these measurements were engendered by the disabilities of subjects. The maximum oxygen uptake observed and the oxygen pulse were lower than in non-disabled persons. There were no differences in the peak heart rates (180-200 beats/min.) as compared with non-disabled athletes during particular competition situations. Sports characterised by quickness, dexterity and strength are not able to train the cardiopulomnary system substantially. Swimming is recommended as beneficial. Psychological and training physiological considerations suggest that long-distance wheelchair races should be adopted as a Stoke Mandeville event.

Adult↗