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At least 19 recordsLinked to original sources
PubMed1977

A new simple spirometric index for use with bronchial provocation tests.

Spirometric indices such as the forced expiratory volume in one second (FEV1), the maximal expiratory flow rate (MEFR) and the maximal midexpiratory flow rate (MMFR) can be criticized for use with bronchial provocation tests since they are either partly effort-dependent or dependent on the forced vital capacity (FVC). These criticisms can be avoided by the use of a new index corresponding to the volume of air expired in one second starting at 75% of the control FVC, called the (FEV1)-25. This study was performed to evaluate the relative sensitivity of the (FEV1)-25 and the classical FEV1 in detecting airway obstruction caused by an inhaled carbachol aerosol in 20 asthmatic subjects. The mean fall in (FEV1)-25 of 46% following carbachol inhalation compared with a mean fall in FEV1 of 35% indicates that, in addition to its theoretical advantages, the (FEV1)-25 is a sensitive index for use with bronchial provocation tests.

Adolescent↗
PubMed1977

Airway response to short-term inhalation of tobacco smoke. Lack of racial differences.

Airway response to short-term inhalation of cigarette smoke was studied in healthy black subjects. We have measured thoracic gas volume, airway resistance, maximum expiratory flow rates, and closing volume in 12 healthy black volunteers before and after smoking a cigarette. We found a significant reduction in airway conductance and midexpiratory flow rate after smoking the cigarette. The results are similar to those previously observed in white subjects. We conclude from our study that the response to short-term inhalation of cigarette smoke is identical in both white and black subjects.

Adult↗
PubMed1979

Predicting the need for prolonged ventilatory support in adult cardiac patients.

Forty-nine cardiac surgical patients had ventilatory function tests and measurements of maximum inspiratory (MIP) and maximum expiratory (MEP) pressures preoperatively. The differences between the values of various function tests were compared for patients requiring less than 24 hours of ventilator support and those requiring more than 24 hours. There was a significant difference in the mean values for the two groups in vital capacity (VC) first-second forced expired volume (FEV) midexpiratory flow between 50 and 75 (MMEF 50--75) and 75--85 percent of expired volume (MMEF 75--85), and MEP. The standard deviations of each of the variables were so large that the clinical usefulness was limited. However, when discriminant analysis was used for more than one variable, the combination of MMEF 75--85 and MEP predicted success or failure to wean in 24 hours correctly in 90 percent of instances. On the basis of these simple tests, patients predicted to succeed should be weaned from ventilator support on recovery from anesthesia. Those predicted to fail should be placed on intermittent mandatory ventilation (IMV) and should be weaned following a planned, logical process.

Adult↗
PubMed1978

A forced expiration end-segment flow rate to improve diagnosis of reversible bronchial obstruction: a spirographic examination.

An inhalatory bronchodilatory test was performed in two groups of 130 healthy and 89 asthmatics comparable in age, height and weight. All were males aged about 20 years. The bronchodilatory response was assessed by the percent increase after bronchodilation of FEV1, MEF200-1200, MMEF25-75 MEF50-75 (E50-75) and MEF75-90--at last three flow rate percent increases measured before and after bronchodilation at the same level of control FVC. It was found that only MEF75-90, measured as described, could probably significantly improve the diagnostic value of a bronchodilatory test if used in cases in which the FEV1 percent increase remains within the normal range.

Adult↗
PubMed1991

Impaired pulmonary function in schoolchildren exposed to passive smoking. Detection by questionnaire and urinary cotinine levels.

Pulmonary function was evaluated by FEV1, FVC, PEF, MEF50%FVC, MEF25%FVC and MMEF in relation with passive smoking exposure in 143 children aged 6-11 years (mean age = 8.5 +/- 1.6). Passive smoking exposure was evaluated by a questionnaire and by measurement of urinary cotinine levels. Children were divided into different groups: no exposure, low exposure and high exposure. The mean values of each pulmonary function test were compared between the groups and between the different evaluations by Student's test. The evaluation of passive smoking exposure by questionnaire and by urinary cotinine levels separated homogeneous groups of children. The urinary cotinine levels were significantly lower in the non-exposed children than in the other groups (p less than 0.001). Pulmonary function tests, especially MEF50%FVC, MEF25%FVC and MMEF were significantly reduced in exposed subjects (p less than 0.05). These alterations are an index of early involvement of the small airways also in passive smokers. The greater the exposure to passive smoking, the lower the values of the pulmonary function tests.

Child↗
PubMed1976

Lung function changes in smokers with normal conventional spirometry.

The comparative ability to detect early abnormalities in smokers by commonly used lung function tests was studied. Sixty-five healthy male nonsmokers served as a reference group and provided standards for 1-sec forced expiratory volume, vital capacity, end-tidal spirometry, spirometric forced mid-and end-expiratory flows, single-breath diffusing capacity, static lung volumes (helium method), and single-breath N2 closing volume measurements, In the present series of 80 male smokers, the measurements of forced mid-expiratory flow and forced end-expiratory flow did not improve the ability of the more conventional indices, 1-sec forced expiratory volume and the ratio of 1-sec forced expiratory volume to vital capacity, to detect obstructive lung disease. In 71 smokers with normal 1-sec forced expiratory volume and ratio of 1-sec forced expiratory volume to vital capacity, the end-tidal spirometry, diffusing capacity, and residual volume indices revealed 14,20, and 21 per cent of abnormalities. respectively. The single-breath N2 closing volume test (Phase IV/vital capacity and slope of Phase III) detected the greatest number of subtle changes in lung function; this was abnormal in 32 per cent of smokers with normal conventional spirometry. In young or light smokers, Phase IV/vital capacity was more frequently increased than the slope of Phase III; an incerse trend was observed in older or heavier smokers. The single-breath N2 closing volume test also provided the greatest number of abnormal results when other indices were impaired in the same subjects.

Adult↗
PubMed1979

Changes in the forced expiratory spirogram in young male smokers.

Forced expiratory spirograms and peak expiratory flow were measured in 102 resident male medical students (60 nonsmokers and 42 smokers). Forced vital capacity; forced expiratory volume in 1 sec; forced expiratory volume in 1 sec expressed as a percentage of forced vital capacity; forced expiratory flows between 80 and 70 per cent, between 55 and 45 per cent, between 30 and 20 per cent, and between 15 and 5 per cent of the forced vital capacity; forced expiratory time for the last 0.5 liter of the forced vital capacity; and maximal mid-expiratory flow were determined from the forced expiratory spirogram. Peak expiratory flow, all forced expiratory flows (except the forced expiratory volume in 1 sec), and the ratio of forced expiratory volume in 1 sec to forced vital capacity were significantly lower, and forced expiratory time for the last 0.5 liter of the forced vital capacity was significantly higher in the heavy smokers (those who had smoked a lifetime total of more than 10,000 cigarettes) than the nonsmokers. The light smokers (those who smoked a lifetime total of fewer than 10,000 cigarettes) had values between those of nonsmokers and the heavy smokers. Thus, a definite dose-related response to smoking was seen. Flows at lower lung volumes showed greater percentage changes than flows at higher lung volumes. The forced expiratory flow between 30 and 20 per cent of the forced vital capacity was the most sensitive test for detecting abnormality in smokers. Among heavy smokers, 58 per cent had abnormally low forced expiratory flow between 30 and 20 per cent of the forced vital capacity, whereas only 47 per cent had abnormally low ratio of forced expiratory volume in 1 sec to forced vital capacity, and 32 percent had abnormally low maximal mid-expiratory flow. The results show that even subjects with short smoking histories may have changes in pulmonary function that probably reflect narrowing of small airways. Moreover, these changes can easily be detected by simple tests, such as evaluation of a forced expiratory spirogram.

Adult↗
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↗
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↗