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PubMed1978

Comparison of two methods of postoperative respiratory care.

After abdominal surgery, 64 patients were managed with one of the following two techniques of respiratory care: (1) deep breathing by way of a new device, an incentive spirometric three-ball, flow-measuring device (Triflo); and (2) standard episodic intermittent positive-pressure breathing (IPPB) every four hours. Both series of patients received therapy with a bronchodilator drug by nebulization. All patients had preoperative spirometric measurements followed by five consecutive days of therapy and spirometry. Chest x-ray films were obtained for all patients. There were no significant differences between the two methods of respiratory care, but 57 percent (17/30) in the group receiving therapy with IPPB developed pneumonia, atelectasis, or bronchitis, while only 29 percent (10/34) did so in the group using the incentive spirometric device (P less than 0.05). Spirometric differences were minimal, although the trend favored the incentive spirometric device. Principal conclusions were as follows: (1) deep breathing under the conditions of this investigation was equal to episodic therapy with IPPB; and (2) from an economic standpoint, IPPB, as it is currently practiced, may be disadvantageous when compared with the incentive spirometric device.

Abdomen↗
PubMed1978

A comparison of the Jones and Stead-Wells spirometers.

A comparison was made between the noncounterweighted Jones and Stead-Wells spirometers, and "conversion factors" were determined for the forced expiratory volume in one second (FEV1) and the forced vital capacity (FVC). A cross-sectional study produced a high correlation between the instruments for these two measurements, yielding quadratic and linear regression equations ("conversion factors") for FEV1 and FVC, respectively. Standard deviations of measurements were similar for both spirometers. Results from a longitudinal study agreed with the "conversion factors" predicted from the cross-sectional study; however, significant day-to-day variability was observed by both spirometers. Neither spirometer met all of the technical recommendations proposed by the Committees on Environmental Health and Respiratory Physiology of the American College of Chest Physicians; however, the Stead-Wells water-sealed spirometer complied more often than the Jones waterless spirometer (Pulmonor). In addition, the open-circuit procedure used for the Jones spirometer required more corrdination in the subject than did the closed-circuit procedure employed in this study for the Stead-Wells spirometer; however, with application of the "conversion factors," both instruments, yield comparable data and prove adequate for spirometric studies.

Forced Expiratory Flow Rates↗
PubMed1979

Dysfunction of small airways following pulmonary injury due to nitrogen dioxide.

Serial physiologic studies were performed to characterize both the immediate and delayed effects of a single occupational exposure to nitrogen dioxide in a nonsmoker. During the initial acute stage of pulmonary edema, the abnormal static pressure-volume curve and decreased static compliance corresponded to a reduction in pulmonary volume. During the delayed acute stage, elastic recoil and properties of resistance to flow were normal, but dynamic compliance was reduced and dependent on respiratory frequency, and oxygen transport was abnormal during exercise, which is consistent with dysfunction of the small airways.

Forced Expiratory Flow Rates↗
PubMed1980

The respiratory effects of regular cigarette smoking in women. A five-year prospective study.

Over a five-year period a consistent habit of smoking or nonsmoking was maintained by 302 women (aged 25 to 54 years at the beginning of the study). There were 130 nonsmokers, 40 ex-smokers, and 15 light, 46 moderate, and 71 heavy smokers. Smokers without serious disability who had stopped smoking had a very low prevalence of respiratory symptoms and showed worsening of pulmonary function over the years similar to life-long non-smokers. Although there is a dose-related response to cigarettes, individual susceptibility also plays an important role in determining the respiratory effect of smoking. A range for change in ventilatory function over a five-year period in apparently healthy nonsmoking women is provided. Using this range, it is possible to identify susceptible smokers who show deterioration in ventilatory function that is more rapid than normal. Repeated spirometric studies may be useful in selecting a group at greatest risk of developing later disabling chronic obstructive pulmonary disease.

Adult↗
PubMed1981

Modification of the effect of fiberoptic bronchoscopy on pulmonary mechanics.

Thirty-three patients who were to undergo diagnostic fiberoptic bronchoscopy were studied. Pulmonary function tests were performed before the procedure, after topical lidocaine anesthesia, and immediately and four hours after bronchoscopy. Nine patients received aerosolized isoproterenol (Isuprel) before the topical anesthesia, and nine received aerosolized atropine. Pulmonary function tests were also performed after this intervention. In those patients receiving no premedication, all the indices of expiratory flow were reduced significantly immediately after bronchoscopy, and after the topical anesthesia, the FEV1 and FVC were significantly reduced. In the atropine groups, the FVC and FEV1 increased significantly after atropine, and increased still further following topical lidocaine anesthesia. By four hours after bronchoscopy, however, the midmaximal expiratory flow ws significantly reduced. In the isoproterenol group, only the FEV1 was significantly improved by the drug, and this improvement persisted even after the lidocaine. It decreased transiently immediately after bronchoscopy, but by four hours, was significantly above baseline again. The FVC diminished significantly immediately after bronchoscopy. It is concluded that fiberoptic bronchoscopy deleteriously affects pulmonary function and that inhaled isoproterenol or atropine largely protects against these deleterious effects.

Adult↗
PubMed1981

Passive smoking. Effects on bronchial asthma.

Ten patients with bronchial asthma and ten control subjects were exposed to sidestream cigarette smoke (passive smoking) for one hour in an environmental chamber. All subjects showed the same increase in carboxyhemoglobin as a result of the exposure: 0.40 percent. The asthmatic group demonstrated a significant linear decrease in pulmonary function during this exposure. After one hour of smoke, FEV1 decreased 21.4 percent, FEF25-75% decreased 19.2 percent, and FVC decreased 20.0 percent in the asthmatic patients. These alterations were readily reversible in all subjects when given inhalations of metaproterenol following the exposure. The control subjects showed no change in pulmonary function when exposed to identical conditions. These data show that nonsmokers with bronchial asthma are at risk when exposed to sidestream cigarette smoke in an environmental chamber.

Adult↗
PubMed1981

Lung mucociliary clearance in patients wit Young's syndrome.

Lung mucociliary clearance was measured in 14 patients with primary obstructive azoospermia and chest involvement (Young's syndrome) using the objective, in vivo radioaerosol technique. Lung mucociliary transport was significantly reduced in patients with Young's syndrome compared to 14 control subjects matched for physical characteristics, tobacco consumption and initial topographic distribution of tracer particles within the lungs. This finding indirectly supports the hypothesis that congenital abnormality in the propulsion of sperm in the ciliated epididymis results in the absence of sperm in the ejaculate.

Adult↗
PubMed1982

Assessment of time-volume and flow-volume components of forced vital capacity. Measurement with spirometry, body plethysmography and respiratory inductive plethysmography in nonsmokers and smokers.

The purpose of this investigation was to assess the effectiveness of the time-volume and flow-volume components of the forced vital capacity measured by simultaneous spirometry, respiratory inductive plethysmography, and body plethysmography in detecting small airway disease. Spirometry measured the exit of gas from the lungs, whereas body plethysmography measured both the exit of gas and alveolar gas compression. Respiratory inductive plethysmography, which reflected change in thoracic volume, provided semi-quantitative data f both gas exit and alveolar gas compression which generally lay between spirometry and body plethysmography. In nine nonsmokers and 12 smokers (six with small airway disease as defined by abnormal closing volumes and alveolar uniformity), analysis of forced vital capacity revealed that the only test which differentiated nonsmokers from smokers was the higher spirometric estimation of maximum expiratory flow measured at 25 percent VC in nonsmokers. Combining flow measure at the mouth with volume referenced to change in alveolar gas volume as measured by body or respiratory inductive plethysmography did not differentiate nonsmokers from smokers. Moment analysis performed of forced vital capacity with all of the three devices did not distinguish nonsmokers from smokers. The data in this study and a review of other investigations indicate that the time-volume and flow-volume components of the forced vital capacity on air breathing are not very sensitive in detecting early lung disease in smokers.

Adolescent↗
PubMed1982

The UCLA population studies of chronic obstructive respiratory disease. 5. Agreement and disagreement of tests in identifying abnormal lung function.

The relative sensitivity and specificity of symptoms, spirometry, the flow-volume (FV) curve, the single-breath nitrogen test (SBNT), and specific airway conductance (SGaw) were estimated by cross comparison of these tests with the FEV1/FVC ratio and other tests in 1,201 residents of Los Angeles. Spirometry and the flow-volume curve were estimated to be the most sensitive, yet reasonably specific composite measures, and FEV1/FVC and V75 to be the most sensitive individual indices. Among current smokers, FEV1/FVC was more frequently abnormal (23 percent) than FEF25-75% (16 percent), showed higher concordance with an abnormal FEF25-75% (88 percent), and identified a greater percentage of individuals as abnormal when the FEF25-75% was normal (9 percent) than vice versa. SGaw and SBNT showed a poor concordance with FEV1/FVC and identified more individuals as abnormal who had a normal FEV1/FVC. Although the proportion of current smokers with productive cough was relatively high (26 percent), none of the function tests showed a reasonable concordance with this symptom. These findings suggest that: 1) spirometry, the flow-volume curve, V75 and FEV1/FVC are relatively sensitive and specific indicators of respiratory impairment; 2) spirometry and the FV curve provide similar but not completely overlapping information; 3) SGaw and SBNT yield different (or less specific) information than the other tests; and 4) effects of cigarette smoking identified by productive cough are different from those identified by other tests.

Adult↗
PubMed1982

Comparison of the beta 1 and beta 2 adrenoceptor blocking properties of acebutolol and propranolol.

The purposes of this study were to evaluate the beta 1 and beta 2 adrenoceptor blocking properties of acebutolol and propranolol and measure the plasma levels of acebutolol, its acetylated metabolite and propranolol. Ten patients with reversible obstructive airways disease and hypertension received two separate dose levels of acebutolol and propranolol for five days each. Cardioselective properties were assessed by determining the beta 1 and beta 2 adrenergic-stimulating effects of terbutaline 5 mg before and at the end of each five-day treatment period. Both acebutolol and propranolol were clinically well tolerated. Following study drug there was a 100 percent inhibition of the beta 1 terbutaline effect, and an approximate 83 percent inhibition of the beta 2 terbutaline effect. There were no clinically significant differences between acebutolol and propranolol. The acetylated acebutolol metabolite accumulated levels two to three times higher than the parent compound, and its effects may have destroyed the cardioselectivity of acebutolol. Thus, acebutolol did not demonstrate clinically relevant cardioselectivity.

Acebutolol↗