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PubMed1988

Bronchial responsiveness after inhalation of cotton bract extract.

This study examined nonspecific airway responsiveness to methacholine (MC) after inhalation of cotton bract extract (CBE). In a randomized double-blind, crossover trial, 13 healthy volunteers underwent an MC inhalation challenge test prior to inhalation of CBE and normal saline solution (NSS) aerosol sham as well as 2, 8, 24, and 168 h (7 days) later. The response parameter was the concentration of MC required to induce a 25% decrement in the maximal expiratory flow at 40% of the vital capacity below total lung capacity on the partial expiratory flow-volume curve (PC25MEF40%(P]. Five of 13 subjects demonstrated a ventilatory response to CBE with a 20% or larger decrement in the MEF40%(P); no subject demonstrated such change with NSS. For the group, the maximal decrement in MEF40%(P) was to 76.5 +/- 20.3% of baseline (mean +/- SD), occurring approximately 60 to 90 min after provocation, whereas the largest decrement after normal saline was to 88 +/- 10.6% of baseline, occurring immediately after inhalation. Changes in airway responsiveness to MC were transient. For example, the PC25MEF40%(P) for the group (mean +/- SD) was 51.3 +/- 41.1 mg/ml at baseline and 25.8 +/- 30.3 and 52.2 +/- 57.3 mg/ml at 2 and 8 h. After a pre-sham baseline of 50.4 +/- 43.2 mg/ml, PC25MEF40%(P) was 57.6 +/- 83.8 and 153.8 +/- 148 mg/ml at 2 and 8 h. Repeated measures ANOVA on these acute, same-day changes (i.e., 2 and 8 h after provocation) demonstrated a statistically significant effect of CBE on airway responsiveness (p = 0.048). These data demonstrate that inhalation of CBE, in addition to bronchospasm, causes a transient increase in airway responsiveness.

Administration, Inhalation↗
PubMed1975

Bronchoconstrictor effects of a deep inspiration in patients with asthma.

A deep inspiration from functional residual capacity to total lung capacity, performed at a low flow rate by a group of 40 unselected adult patients with asthma, yielded an immediate and transient increase (71 per cent, P smaller than 0.001) in specific airway resistance. In 2 of the 40, deep inspiration provoked an attack of asthma. The effect of deep inspiration can be attributed to a vagal bronchoconstrictor reflex, because it was prevented or decreased in most of the cases by inhalation of an anticholinergic drug. Beta-adrenergic blockade by propranolol potentiated in a minority of subjects the bronchoconstrictor response to deep inspiration. Deep expiration also induced a bronchoconstrictor effect, which was weaker than that of deep inspiration. It follows that functional studies of asthmatics may be biased if the technique requires maximal respiratory maneuvers.

Adolescent↗
PubMed1981

Airway reactivity in cotton bract-induced bronchospasm.

Most healthy subjects challenged with cotton bract extract demonstrate some degree of bronchospasm. This response has been associated with the endogenous production of histamine by the inhalation of cotton bract extract. We examined whether this responsiveness reflects increased sensitivity to histamine. Thirty-one healthy subjects were screened for sensitivity to cotton bract extract administered by nebulization. Pulmonary function was measured using partial expiratory flow-volume curves on which flows at 60% of the control vital capacity below total lung capacity were measured (MEF40%(P)). Responders were defined as subjects who exhibited a 20% or greater decrease in MEF40%(P) after 10 min inhaling cotton bract extract. Of those screened, 10 subjects were responders. From the remaining nonresponders, 11 consecutive subjects were selected. The maximal decrease in MEF40%(P) in responders was 40.5 +/- 5.1%, compared to 10.9 +/- 2.2% in nonresponders. The dose-response relationship for histamine was measured in all subjects, using inhalations of progressively more concentrated histamine solutions. The mean +/- SEM threshold for the responders was 38.4 +/- 7.4 mg of histamine per ml, compared to 42.2 +/- 6.8 mg of histamine per ml for responders (difference not significant). The percentage decrease in MEF40%(P) at the threshold dose was 27.6 +/- 3.7% for responders and 32.4 +/- 5.2% for nonresponders (difference not significant). We conclude that healthy subjects sensitive to cotton bract extract do not exhibit increased reactivity to histamine. This suggests that responders are not, in general, subclinical asthmatics, and that the difference between responders and nonresponders to CBE is not due to increased histamine sensitivity among responders.

Adult↗
PubMed2006

Sex differences in thoracic adaptation to pulmonary hyperinflation in cystic fibrosis.

Sex differences in thoracic adaptation have been reported in patients with cystic fibrosis (CF). The interplay between the pattern of thoracic adaptation and the function of the respiratory muscles in male and female CF patients with pulmonary hyperinflation was investigated. Thoracic dimensions and diaphragm length were measured at residual volume, functional residual capacity and total lung capacity using chest radiography in 23 CF (12 males) and 18 normal (11 males) subjects. Respiratory muscle recruitment during resting breathing was assessed by recording intrathoracic and intra-abdominal pressures. In female CF patients, ribcage expansion was predominant, tending to preserve diaphragm length. In male CF patients, thoracic configuration was normal and diaphragm shortening consequently greater. Ribcage cross-sectional area for a given rib inclination was greater in CF patients, indicating a structural expansion of the ribcage 2.5 times greater in females than males. The contribution of inspiratory ribcage muscles to inspiratory pressure was also greater relative to the diaphragm in the CF group. In conclusion, a structural expansion of the ribcage occurs in cystic fibrosis patients with lung hyperinflation that is greater in females than males. This is associated with an apparent greater contribution of inspiratory ribcage muscles to inspiratory pressure.

Adaptation, Physiological↗
PubMed1975

Pulmonary function studies in ex-heroin users.

Pulmonary function tests were performed on a group of 22-ex-heroin addicts with no known pulmonary disease or symptoms. Vital capacity and total lung capacity were normal in all but four patients. Only two patients had evidence of moderately severe airway obstruction. However, the single breath diffusing capacity (Dco) was significantly reduced in many of the patients and averaged 81 percent of predicted for the entire group. Patients with most severe reduction of Dco also had reduction of lung volumes. In addition, six patients had increased lung recoil force (Pmax) and decreased lung compliance. There was no correlation between degree of functional impairment and duration or amount of durg use, incidence of overdose or intravenous injection of crushed tablets. Followup studies in four patients after several months on methadone maintenance showed improvement in lung volumes and/or Dco. Possible etiologic considerations to explain these abnormalities were previous subclinical pneumonias, foreign body granulomas, previous pulmonary edema or other direct toxic effect on alveolocapillary membrane as the result of use of drugs.

Adult↗
PubMed1978

Changes in pulmonary mechanics and gas exchange following thoracocentesis.

In nine patients with large pleural effusions, we studied the changes in pulmonary mechanics and gas exchange that occurred in the first three hours following removal of 600 to 1,800 ml of fluid by thoracocentesis. There was a small but significant increase in the functional residual capacity and total lung capacity but no change in residual volume and vital capacity. Calculated pulmonary shunt fraction did not change. We could not relate the subjective improvements noted by patients after thoracocentesis to the changes in pulmonary volumes or blood gas levels.

Adult↗
PubMed1985

Airway reactivity and cotton bract-induced bronchial obstruction.

Most seemingly healthy persons challenged with an aerosol of cotton bract extract develop some degree of bronchospasm. The role of nonspecific reactivity of the airways in this reaction to cotton bract extract is undefined. We examined the relationship between airway responses to cotton bract extract and to methacholine, as well as between airway responses to cotton bract extract and to a bronchodilator. Twenty-two healthy subjects were screened for sensitivity to inhaled cotton bract extract. Pulmonary function was measured using partial expiratory flow-volume curves on which flow at 60 percent of the control vital capacity below total lung capacity was measured (MEF40%[P]) following ten minutes of inhalation of cotton bract extract. In the group screened, 12 were found to be responders to the extract, with drops in MEF40%(P) of 20 percent or more, and ten were found to be nonresponders. On separate days, we measured the responses of our subjects' airways to inhaled metaproterenol and methacholine. The mean threshold dose for methacholine in the responding group was 26.8 mg/ml, as compared to 55.6 mg/ml for the nonresponders (t = 2.52; p less than 0.05). Furthermore, the mean percent increase in MEF40%(P) following inhalation of metaproterenol was 41 percent in responders and 24 percent in nonresponders (t = 2.19; p less than 0.05). We conclude that some responders to cotton bract extract exhibit greater reactivity of the airways than nonresponders.

Adult↗
PubMed1985

Pulmonary function and ventilatory response to chemical stimuli in familial myopathy.

We studied the pulmonary function and ventilatory response to carbon dioxide and hypoxia in three sisters aged 16, 13, and 10 years who presented with droopy eyelids, external ophthalmoplegia, hearing loss, speech difficulty, and truncal muscular weakness. Pulmonary function test results showed decreased maximum static pressure, reduced vital capacity and total lung capacity, normal functional residual capacity, elevated residual volume, and reduced dynamic pulmonary volumes. The degree of functional abnormality paralleled the severity of clinical manifestations. The characteristic picture of pulmonary functional abnormality was distinct from either restrictive disorders of pulmonary origin or obstructive pulmonary diseases. The ventilatory response to hypoxia was markedly diminished and hypercapnic response was moderately diminished in all three patients.

Adolescent↗
PubMed1986

Gastric surgery for respiratory insufficiency of obesity.

Morbid obesity is often associated with severe respiratory insufficiency, commonly known as the pickwickian syndrome. This can be divided into the following two primary breathing disorders which can affect patients alone or in combination: the obstructive sleep apnea syndrome (SAS); and the obesity-hypoventilation syndrome (OHS). Thirty-eight (14 percent) of 263 morbidly obese patients with respiratory insufficiency of obesity underwent gastric surgery for weight reduction. Ten had OHS, nine has SAS, and 19 had both. Of these patients, one died of postoperative complications, one died at five weeks with an inconclusive autopsy, one was lost to follow-up, and the time since surgery was too short (less than three months) in three. A total of 30 patients lost 45 +/- 25 percent (p less than 0.0001) of excess body weight within 3 to 12 months following surgery, when repeat pulmonary studies were done. Most patients continued to lose additional weight until two years, when they had lost 62 +/- 26 percent of excess weight. Nine patients failed initial surgery (gastroplasty); seven of these were successfully converted to gastric bypass. Weight loss was associated with a significant decrease in the percentage of sleep apnea from 44 +/- 15 to 8 +/- 11 (p less than 0.0001). In patients with OHS, the arterial oxygen pressure (PaO2) increased from 53 +/- 9 to 68 +/- 11 mm Hg (p less than 0.0001), and the arterial carbon dioxide tension decreased from 51 +/- 7 to 41 +/- 4 mm Hg (p less than 0.0001). Pulmonary function tests in the patients with OHS revealed significant increases, as a percentage of predicted normal, in the forced vital capacity, forced expiratory volume in one second, expiratory reserve volume, functional residual capacity, and total lung capacity. Secondary polycythemia, defined as a hemoglobin level greater than 16 g/dl associated with a PaO2 less than 60 mm Hg, was noted in 13 of 29 patients with OHS. This fell from 16.9 +/- 1.1 to 14.9 +/- 1.7 g/dl (p less than 0.001) after weight loss and improved pulmonary function.

Adult↗
PubMed1996

Frequency and clinical implications of increased pulmonary artery pressures in liver transplant patients.

OBJECTIVE: To characterize the pulmonary hemodynamics and identify predictors of pulmonary hypertension in a group of patients before liver transplantation and to determine whether pulmonary hypertension in these patients is related to survival. MATERIAL AND METHODS: In 362 patients before their first liver transplantation (between 1985 and 1993), the clinical history, laboratory data, and results of pulmonary function tests were recorded. Pulmonary artery (PA) catheterization was performed after induction of anesthesia at the time of transplantation. Monthly follow-up was maintained. RESULTS: A hyperdynamic circulation was often present -- an increased mean cardiac output (7.6 L/min), increased mean PA pressure (20.9 mm Hg), correlation of mean PA pressure with cardiac output (r = 0.25; P<0.001), and decreased mean pulmonary vascular resistance (60 dynes times s/cm5). Mean PA pressures were more than 25 mm Hg in 72 patients (20%). Pulmonary hypertension (defined as mean PA pressure of more than 25 mm Hg and pulmonary vascular resistance in excess of 120 dynes times s/cm5) occurred in 15 patients (4%). Pulmonary function tests revealed obstruction in 7%, restriction in 18%, and low diffusing capacity in 46%. By univariate analysis, lower forced expiratory volume in 1 second, forced vital capacity, and total lung capacity were the only preoperative factors associated with pulmonary hypertension (P<0.05). Survival was significantly lower in patients with acute fulminant hepatitis (P<0.001), the group with the highest mean PA pressure, than in those with other diagnoses. Increased PA pressures or mild to moderate pulmonary hypertension was not found to be associated with a worse survival by univariate or multivariate analysis. CONCLUSION: Increased PA pressure is common in liver transplant patients (20%). "True" pulmonary hypertension occurred in only 4% of our patients and was not associated with an adverse outcome.

Adolescent↗
PubMed1999

Pulmonary function in children affected by juvenile spondyloarthropathy.

OBJECTIVE: Pleuropulmonary involvement in adult spondyloarthropathy (SpA) has been thoroughly investigated. SpA is usually detected by conventional radiology as fibrosis of the upper lobes in about 30% of asymptomatic patients. Pulmonary function tests (PFT) reveal decreased vital capacity and total lung capacity, as well as increased residual volume. Juvenile SpA (JSpA) is a rare clinical condition, and no extensive investigations have been carried out on pulmonary involvement in JSpA. We studied prevalence and features of PFT alterations in patients with JSpA over a 2 year followup and analyzed the relationship between PFT and disease duration, disease activity, and chest and spine mobility. METHODS: Eighteen patients with JSpA, with no clinical signs of lung disease and normal chest radiographs, underwent PFT--static and dynamic volumes, diffusing capacity for carbon monoxide (DLCO), at enrollment (T0), at 12 months (T1), and at 24 months later (T2). Disease activity was defined at each investigation by clinical and hematological data. RESULTS: Significant functional lung impairment was detected in 33% of patients (reduced forced vital capacity in 22% and DLCO in 11%). No significant change in the prevalence and features of PFT alterations was detected at T1 and T2; no relationship was found between PFT and duration, activity, and clinical scores of the disease. CONCLUSION: Thirty-three percent of JSpA patients without clinical symptoms and no radiological findings of lung involvement show PFT alterations, mainly characterized by a restrictive pattern. No progression or modification in PFT developed over 2 years. No correlation was found between PFT and disease duration, activity, and clinical scores.

Adolescent↗
PubMed2000

Pulmonary function changes following surgical correction for pectus excavatum.

OBJECTIVE: To assess whether and to what extent pulmonary function returns to normal after surgical correction for pectus excavatum. METHODS: Twenty-seven patients who could be examined in person at the outpatient department of our hospital were included in this study. Of these patients, 24 were boys and 3 were girls, with age ranging from 3 to 16 years (mean: 8.67 years). The mean age at surgery was 4 years and mean years at follow-up was 6.8. Pulmonary function measurements included inspiratory vital capacity (IVC), total lung capacity (TLC), residual volume (RV), functional residual capacity (FRC), RV/TLC ratio, maximal voluntary ventilation (MVV), forced ventilatory capacity (FVC), forced expiratory volume in one second (FEV1), maximal mid-expiratory flow (MMEF), maximal expiratory flow at 75% vital capacity (V75), maximal expiratory flow at 50% vital capacity (V50), maximal expiratory flow at 25% vital capacity (V25) and breathing reserve ratio (BR). RESULTS: TLC, FRC, MVV, MMEF, V75 and V50 were not different from normal values. IVC, FVC, FEV1 and V25 were significantly decreased compared with normal values. RV and RV/TLC were high in 87.5% cases. CONCLUSIONS: Preoperative symptoms improved substantially after operation. Little airway obstruction was observed postoperatively, suggesting that patients with pectus excavatum should have surgery as early in life as possible, preferably by age 3.

Adolescent↗
PubMed2003

The acute effects of cilazapril on pulmonary function tests and arterial blood gas changes in patients with pulmonary hypertension.

The aim of the present study was to evaluate pulmonary function tests and arterial oxygen transport in patients with pulmonary hypertension due to congestive heart failure before and after cilazapril treatment. Thirty patients (16 men and 14 women, mean age, 65 +/- 18 years) with congestive heart failure and 30 healthy volunteers (20 men and 10 women, mean age 59 +/- 12 years, p > 0.05) were included in the study. All patients underwent evaluation of pulmonary function by spirometry and arterial blood gas analysis. Arterial oxygen saturation and arterial oxygen transport changed significantly after treatment (81 +/- 7 to 87 +/- 8 and 317 +/- 74 to 392 +/- 8, respectively). Forced expiration volume in 1 second, vital capacity and total lung capacity were increased after cilazapril treatment (2.55 +/- 0.7 to 2.61 +/- 0.8, 3.2 +/- 0.9 to 3.3 +/- 1.0 and 3.6 +/- 0.9 to 4.1 +/- 1.1, respectively, p < 0.05). In conclusion, short-term cilazapril administration improved pulmonary function and arterial oxygen transport because it increased cardiac output, produced pulmonary vasodilatation, improved the pulmonary hemodynamics and removed interstitial fluid.

Adult↗
PubMed2003

[Pulmonary function test before and after operation of coronary artery by-pass surgery].

Respiratory complications after successful CABG operation continuous to have on influence on the immediate recovery of a patient. It was reported that the mortality risk of the CABG patients increased, proportional to the reduction of pulmonary function tests (PFT). In the present study we aimed to investigate PFT values (vital capacity: VC, total lung capacity: TLC, residual volume: RV, functional residual capacity: FRC, force expiratory volume first second: FEV1, force mid expiratory flow: FEF25-75, duration force expiratory flow in vital capacity 25%: FEF25, duration force expiratory flow in vital capacity 50%: FEF50, duration force expiratory flow in vital capacity 75%: FEF75, peak expiratory flow: PEF, RV/TLC, FEF/FIF, FEV1/FVC) and arterial blood gases (pH, PaCO2, PaO2, SaO2) pre- and postoperatively which undergo CABG. The PFT and arterial blood gases values of 20 patients, age between 39-74 years, were measured that were undergo CABG operation before a week and three months after.The measured PFT values of 20 patients were recorded by system 2400 computerized and sensor medix 6200 and arterial blood gases analysed by radiometer ABL 300. The results were compared by the time and periods of before and after CABG operation, statistically evaluated the pearson's correlation and Student's t-test. In the results the postoperative PFT values were significantly decreased (p< 0.05, p< 0.001). But the RV, RV% and RV/TLC values were not changed significantly. In arterial blood gases values were not significantly changes. To avoid the postoperative complications we suggested that should be done the PFT and arterial blood gases measurement preoperatively.

Adult↗
PubMedDate not supplied

[Correlation of the size of the residual volume measured by whole body plethysmography and the single breath helium dilution method].

The value of residual volume, intrathoracic gas volume, functional residual capacity and total lung capacity obtained by the method of body plethysmography and helium dilution method was correlated by single-breath diffusing capacity. These parameters were correlated in 22 patients who had had complete functional diagnostics of the lung: spirometry, flow volume curve, body plethysmography and single-breath diffusing capacity. All findings were within normal limits, which was a condition for selection of patients for our group. Statistically significant differences (p = 0.01) of t-test were established between residual volumes by the plethysmographic and helium dilution method of single-breath diffusing capacity. The residual volume obtained by body plethysmography showed higher values for 526 ml, or 30%. The intrathoracic gas volume showed higher values for 682 ml, or 17%. Inspite of the fact that values of RV obtained by two methods had statistically significant differences, they were still within normal limits, if presented as percent of the predicted value.

Adult↗
PubMed1988

Cardiopulmonary function in pectus excavatum.

The results of recent studies clearly support a cardiopulmonary impairment resulting from pectus excavatum, but resolving the apparent discrepancies between studies is necessary. Several factors must be taken into consideration. The severity of the deformity of the chest wall must be defined, whether by the sternovertebral distance or by various means proposed by others. Without some index of the degree of sternal depression, it is impossible to compare patients or results among studies. No study has enrolled a sufficient number of patients to provide an accurate correlation between the severity of the deformity and the extent of the cardiopulmonary deficit, nor has any defined how severe the deformity must be to result in cardiopulmonary dysfunction. The second factor that is important in evaluating results is what controls were used. Studies in which each patient functioned as his own control after surgical repair are preferable. In the pediatric age group where growth and increased pulmonary parameters would be expected, the follow-up studies should be performed at a defined time after surgical treatment. Studies completed years later cannot assess the effect of surgical repair upon cardiopulmonary function. Studies wherein persons matched for age and height to serve as controls are available from the same laboratory are also needed. The degree of co-operation and effort of patients will vary, particularly in the pediatric age group. Constancy of the experimental protocol and personnel is important. Least reliable are reports of experimental findings compared with standardized normal values. In early studies, measurements of vital capacity and total lung capacity produced variable results when compared with normal persons matched for age. The wide range of "normal values" makes statistical comparison difficult, if not impossible. A wide spectrum of cardiopulmonary function exists among individuals, depending upon prior physical training and body habitus. Sufficient physiologic reserve is generally present, such that extensive impairment must exist before patients become symptomatic at rest. Physiologic reserve during exercise is rapidly consumed and differences can be more readily determined. Exercise studies must go beyond the measurement of intracardiac pressures and pulmonary volumes at rest.(ABSTRACT TRUNCATED AT 250 WORDS)

Funnel Chest↗
PubMed1988

Dose-related antagonism of leukotriene D4-induced bronchoconstriction by p.o. administration of LY-171883 in nonasthmatic subjects.

Leukotriene D4 (LTD4) has been suggested as a proinflammatory mediator in asthma. We have investigated the inhibitory activity of the p.o. LTD4 antagonist LY-171883 (1-[2-hydroxy-3-propyl]-4-[4-(1H-tetrazol-5-yl)butoxy]phenyl]et hanone) on LTD4-induced bronchoconstriction in nonasthmatic subjects, in a double-blind, placebo controlled, randomized, cross-over study. Twelve subjects, mean age 26.3 +/- 1.7 years, participated. On 4 separate days, base-line measurements of forced expiratory volume in 1 second (FEV1) and maximum flow at 70% of vital capacity below total lung capacity (Vp30) were performed, after which subjects ingested either 50 or 200 or 400 mg of LY-171883, and then undertook a dose-response study with inhaled LTD4. Measurements of FEV1 and Vp30 were made at intervals for 8 min after inhalation of each dose of LTD4, and increasing doses administered until FEV1 had fallen by greater than 20% or the maximum cumulative dose of LTD4 (88.2 nmol) had been given. Cumulative dose-response curves were constructed on a logarithmic scale, and the provocation doses of LTD4 producing a 12% fall in FEV1 (PD12 FEV1) and a 30% fall in Vp30 (PD30Vp30) after placebo determined by linear interpolation to be 5.5 (0.9-176.4) and 1.2 (0.1-6.2) nmol, respectively. Following the 50-, 200- and 400-mg doses of LY-171883, the geometric mean PD12 FEV1 values were 7.0 (NS), 10.5 (NS) and 25.3 (P less than .01) nmol, respectively, whereas corresponding values for PD30Vp30 were 1.7 (NS), 2.6 (NS) and 6.1 (P less than .01) nmol.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetophenones↗
PubMed1985

Airway responses to sulfur dioxide and methacholine in asthmatics.

Sulfur dioxide (SO2) is a common air pollutant found in the workplace. Considerable variation exists in the airway responses of asthmatics to the inhalation of SO2. To determine if such variation among asthmatics is related to nonspecific airway reactivity, we compared the threshold doses of methacholine and SO2 required to produce significant changes in flow rates at 60% of the vital capacity below total lung capacity on the partial expiratory flow volume curve in a group of eight mildly asthmatic subjects. A significant correlation between the dose of SO2 and the dose of methacholine required to produce bronchoconstriction (r = .86, p less than .05) was observed, suggesting that there is a relationship between the response to SO2 and the response to methacholine in mildly asthmatic individuals. More generally, nonspecific airway hyperreactivity may help to predict untoward airway responses to inhaled SO2 in the workplace.

Adult↗