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PubMed1980

Chronic bronchitis and decreased forced expiratory flow rates in lifetime nonsmoking grain workers.

To determine whether clinical symptoms and pulmonary function abnormalities were more common in lifetime nonsmoking grain elevator workers exposed to grain dust than in lifetime nonsmoking community control subjects who were not occupationally exposed to dust, we obtained an occupational health questionnaire, spirometric variables, and flow-volume curves on 90 lifetime nonsmoking grain workers and 90 lifetime nonsmoking community control subjects. For these groups we calculated the prevalence of chronic bronchitis, defined as daily production of phlegm for 3 months/yr for at least 2 yr. The prevalence of chronic bronchitis was higher in nonsmoking workers (23.1%) than in nonsmoking control subjects (3.3%) (p less than 0.01). Nonsmoking grain workers had lower mean values than did nonsmoking control subjects for maximal mid-expiratory flow rate (p less than 0.01) and for maximal expiratory flow at 50% of vital capacity (p less than 0.01). We conclude that exposure to grain dust inlifetime nonsmoking grain workers is associated with an increased prevalence of chronic bronchitis and evidence of airflow obstruction.

Adult↗
PubMed1984

Kyphosis and pulmonary function in cystic fibrosis.

Spine deformity and chronic pulmonary disease are commonly seen in patients with cystic fibrosis (CF). In order to assess the prevalence of kyphosis, a retrospective evaluation of all initial standing chest radiographs of our CF patients matched with our "reference" population was undertaken. We also studied the possible correlation between the degree of kyphosis and the pulmonary function tests ( PFTs ), consisting of thoracic gas volume and maximal expiratory flows. In our population, the study confirmed an increased prevalence of kyphosis in CF patients (p less than .01), which occurred mostly in girls after 12 years of age (p less than .018). The kyphosis appeared to be, in most instances, of mild degree and was not related to any of the PFTs . No measurable increase of kyphosis was observed over a 3-year period in the group. Longer prospective study and the relationship of kyphosis to endocrine function in CF at puberty should be undertaken.

Adolescent↗
PubMed1999

Clickhaler (a novel dry powder inhaler) provides similar bronchodilation to pressurized metered-dose inhaler, even at low flow rates.

STUDY OBJECTIVE: Comparison of the bronchodilator response to an albuterol novel dry powder inhaler (DPI) (Clickhaler [CH]; ML Laboratories PLC; St. Albans, UK) activated at various inspiratory flow rates and to an albuterol pressurized metered-dose inhaler (pMDI) by patients with moderate to moderately severe stable asthma. DESIGN: Randomized, double-blind, placebo-controlled comparison of the bronchodilator response to albuterol DPI (200 microg) at inspiratory flow rates of approximately 15, 30, and 60 L/min in patients with stable asthma with demonstrated reversibility to albuterol. Active (albuterol via pMDI inhaled at 30 L/min) and placebo controls were included. SETTING: Single center study at the chest/allergy unit of a teaching hospital in Canada. PATIENTS: Sixteen patients with moderate to moderately severe stable asthma. MEASUREMENTS AND RESULTS: Efficacy end points were FEV1, FVC, FEV1/FVC, maximum expiratory flow, and forced expiratory flow between 25% and 75% of vital capacity. Safety end points included heart rate, BP, and tremor. There was no significant difference between the bronchodilator response to albuterol via the CH at 15, 30, and 60 L/min inspiratory flow rate and, at all flow rates, no significant difference was found comparing albuterol CH with the pMDI. All of the techniques for delivering albuterol provided significantly better bronchodilatation than placebo. Adverse events were minimal and did not differ between CH and pMDI or between the various flow rates inhaled through the CH. CONCLUSION: A novel passive albuterol DPI (CH) provides a similar bronchodilator response at 15, 30, and 60 L/min inspiratory flow rates compared with a pMDI used optimally.

Administration, Inhalation↗
PubMed2000

Airway hyperreactivity in subjects with tetraplegia is associated with reduced baseline airway caliber.

OBJECTIVES: We administered aerosolized histamine to 32 subjects with tetraplegia to determine whether there were differences in spirometric and/or lung volume parameters between responders and nonresponders. RESULTS: Baseline pulmonary function parameters revealed mild to moderate restrictive dysfunction. We found that 25 subjects (78%) were hyperreactive to histamine (mean provocative concentration of a substance causing a 20% fall in FEV(1) [PC(20)], 1.77 mg/mL). Responders (PC(20), < 8 mg/mL) had significantly lower values for forced expiratory flow between 25% and 75% of the outflow curve (FEF(25-75)), FEF(25-75) percent predicted, and FEF(25-75)/FVC ratio. Among all 32 subjects, the natural logarithmic transformation performed on PC(20) values (lnPC(20)) correlated with FEF(25-75) percent predicted, FEV(1) percent predicted, and FEF(25-75)/FVC ratio but not with FVC percent predicted. Responders with PC(20) values < 2 mg/mL (n = 13) had significantly reduced values for FVC, FVC percent predicted, FEV(1), and FEV(1) percent predicted compared to those with PC(20) values between 2 mg/mL and 8 mg/mL. In addition, among responders, there was a significant correlation between lnPC(20) and FVC percent predicted. A significant relationship was found between maximal inspiratory pressure (PImax) and both FEV(1) percent predicted and FEF(25-75) percent predicted, but not between lnPC(20) and either PImax or maximal expiratory pressure (PEmax). CONCLUSIONS: These findings demonstrate that subjects with tetraplegia who exhibit airway hyperreactivity (AHR) have reduced baseline airway caliber and that lower values for lnPC(20) are associated with parallel reductions in surrogate spirometric indexes of airway size (FEV(1) percent predicted and FEF(25-75) percent predicted) and airway size relative to lung size (FEF(25-75)/FVC ratio). The absence of an association between lnPC(20) and FVC percent predicted for the entire group or between lnPC(20) and either PImax or PEmax indicates that reduced lung volumes secondary to respiratory muscle weakness cannot explain the mechanism(s) underlying AHR. Among responders, however, a possible role for reduction in lung volume, as it pertains to increasing AHR, cannot be excluded. Proposed mechanisms for reduced baseline airway caliber relative to lung size in subjects with tetraplegia include unopposed parasympathetic activity secondary to the loss of sympathetic innervation to the lungs and/or the inability to stretch airway smooth muscle with deep inhalation.

Adult↗
PubMed2004

Increase in alveolar nitric oxide in the presence of symptoms in childhood asthma.

STUDY OBJECTIVES: To determine respective contributions of alveolar and proximal airway compartments in exhaled nitric oxide (NO) output (QNO) in pediatric patients with asthma and to correlate their variations with mild symptoms or bronchial obstruction. PATIENTS AND DESIGN: In 15 asthmatic children with recent mild symptoms, 30 asymptomatic asthmatic children, and 15 healthy children, exhaled NO concentration was measured at multiple expiratory flow (V) rates allowing the calculation of alveolar and proximal airway contributions in QNO, using two approaches, ie, linear and nonlinear models. MEASUREMENTS AND RESULTS: Asymptomatic and recently symptomatic patients were not significantly different regarding FEV(1) and maximum V between 25% and 75% of FVC (MEF(25-75)): FEV(1), 93.3 +/- 13.4% vs 90 +/- 7.5%; MEF(25-75), 70 +/- 22% vs 68 +/- 28% of predicted values, respectively (mean +/- SD). Maximal airway QNO output was significantly higher in recently symptomatic vs asymptomatic patients (p < 0.0001), and in asymptomatic patients vs healthy children (p < 0.02): 134 +/- 7 nl/min, 55 +/- 43 nl/min, and 19 +/- 8 nl/min, respectively. In a multiple regression analysis, variables that influenced airway QNO output were symptoms (p < 0.0001) and distal airway obstruction as assessed by MEF(25-75) (p < 0.05). Alveolar NO concentration (FANO) was significantly (p < 0.03) higher in recently symptomatic than in patients without symptoms, whereas it was not significantly different between asymptomatic patients and healthy children: 7.2 +/- 2.4 parts per billion (ppb), 5.5 +/- 2.7 ppb, and 4.2 +/- 2.0 ppb, respectively. CONCLUSIONS: An increase in FANO was observed in the presence of symptoms, and proximal airway NO output was correlated with distal obstruction during asthma.

Asthma↗
PubMed1975

Cough dynamics in the post-thoracotomy state.

A series of 24 adult male patients undergoing thoracotomy were found to have a reduction in their cough pressures in the immediate postoperative period to 29 percent of their preoperative values. Cough pressures still averaged only 50 percent of control values one week following surgery, with slow return toward normal over the ensuing three weeks. Pain associated with the surgical wound appeared to be primary factor in the patients' inability to cough effectively. The degree of impairment appeared to be related to the extent of the procedure, pressures being altered less in those with limited incision thoracotomies. Ultrasonically nebulized water mist was found to be effective in all but one patient in inducing significantly higher cough pressures and more effective sputum expectoration. Its use should be considered as a simple method of inducing more effective coughs in the postoperative patient.

Adult↗
PubMed1977

New tests for the detection of obstructive pulmonary disease.

Abnormalities in small airways appear to be important in the evolution of chronic obstructive pulmonary disease. Patients with these pathologic lesions may have normal values for airway resistance and forced expiratory volume in one second. Two new tests, the closing volume (CV) and the dependence of maximal flow on density, are believed to be sensitive to abnormalities in the peripheral airways. The CV test detects an increased nonuniformity of changes in volume of pulmonary units. Reduced dependence of flow on density is believed to result from an increase in the peripheral component of the losses of driving pressure which determine maximal expiratory flow. Both tests differentiate smokers with normal conventional spirometric data from age-matched nonsmokers. Although this evidence suggests that these tests can be used to detect abnormalities in small airways, there is very little pathologic confirmation of this belief. The clinical significance of abnormalities in the results of either of these tests in an otherwise normal person has not yet been determined.

Airway Resistance↗
PubMed1984

Bitolterol compared to isoproterenol in advanced chronic obstructive pulmonary disease.

Twenty-eight patients with advanced emphysema and/or chronic bronchitis and severe airflow obstruction were randomly assigned to receive either bitolterol or isoproterenol aerosol delivered by a metered dose device which was administered three times daily. Randomization resulted in similar patients with like degrees of airflow obstruction and responsiveness to a test dose of inhaled bronchodilator. Significantly greater improvement in airflow was achieved by administration of bitolterol compared to isoproterenol. Pharmacologic responses continued after 90 days of daily dosing. Both drugs were well tolerated and side effects included mild degrees of tachycardia for both drugs. Two patients assigned to isoproterenol stopped therapy during the study due to side effects. This study indicates that bitolterol is more effective than isoproterenol in degree and duration of bronchodilatation in patients with advanced chronic obstructive pulmonary disease.

Aged↗
PubMed1988

Ribavirin aerosol in the elderly.

Ribavirin aerosol is effective in treating respiratory syncytial virus and influenzal infections in children and young adults. It has not been studied in elderly patients. We evaluated the safety of ribavirin aerosol in eight elderly volunteers at high risk for influenza. Their mean age was 64 years; seven subjects had chronic obstructive pulmonary disease (COPD). Subjects received ribavirin aerosol for two or six hours with six hours between treatments. Regimens were continued for 96 hours. The drug was well tolerated. Subjects receiving ribavirin for 2 hours demonstrated a significant decrease in their forced expiratory volume in one second, peak expiratory flow rate and flow over the middle 50 percent of the forced vital capacity. These changes were small and the subjects' symptoms remained stable. Subjects receiving ribavirin for 6 hours had no significant changes in pulmonary function. We conclude that ribavirin aerosol is safe in elderly patients with underlying COPD.

Aerosols↗
PubMed1975

The pharmacological assessment of single drugs and drug combinations in exercise-induced asthma.

The relative effectiveness of ephedrine, theophylline, hydroxyzine, and their combinations in relieving cycloergometer exercise-induced asthma were studied in 16 children and adolescents. Ephedrine had no effect on post-exercise asthma, hydroxyzine had weak effect on hastening recovery, while theophylline modified on the post-exercise response significantly. The three drugs together produced an additive effect superior to that of theohylline alone.

Adolescent↗
PubMedDate not supplied

A comparative study of a few tests of dynamic lung function.

A variety of tests like FEV0-76, FEV1, PFR, MEFR is in use for assessment of ventilatory function of the lungs. Each of them has some marginal advantage over the other. It is, therefore, necessary to find out their relative merits and choose the one which can provide the maximum information in a reasonably short time. In this project, a norm of all the above tests for the people of Gujarat of age group 18-20 years has been found, the relative merit of the tests has been discussed and the velocity of air flow at 0.3 sec of expiration has been suggested as the single measurement which may conveniently replace all the other above.

Adolescent↗
PubMed1985

Carbon monoxide diffusing capacity: a reliable indicator of bleomycin-induced pulmonary toxicity.

Seventy-seven untreated patients with germ-cell tumors, of whom 20 had no pulmonary involvement, no clinical or radiological evidence of pulmonary disease, received 6 courses of cisplatin, vinblastine and bleomycin. Pulmonary function tests were performed before, every 3 weeks during treatment, and once a month from then on. The carbon monoxide diffusion capacity tests were normalized with respect to the actual hemoglobin concentration. During treatment a nonsignificant decrease (P greater than 0.05) was seen in the flow volume relationships, but as it was reversible it was attributed to the strenuous treatment. In contrast a significant decrease of 35% (P less than 0.01) in the corrected carbon monoxide diffusion capacity was seen in 15 of 18 evaluable patients with neither clinical nor radiological signs of pulmonary toxicity. The decrease was correlated to the increasing dose of bleomycin (r = 0.63).

Adolescent↗