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At least 451 records · Page 25Linked to original sources
PubMed1991

A prospective study of respiratory failure after high-risk surgery on the thoracoabdominal aorta.

From June 1960 to September 1990, 1414 patients underwent repair of thoracoabdominal aortic aneurysms, of whom 112 (8%) had pulmonary complications requiring respiratory support with tracheostomy; subsequently 45 (40%) died in the hospital. We determined by stepwise logistic regression analysis, in a prospective study of high-risk type I and II thoracoabdominal aortic aneurysms repairs, the independent predictors of respiratory failure, defined as respiratory ventilation exceeding 48 hours after operation. In 98 patients studied, 38 (39%) were women, 60 (61%) were men, 54 (55%) had type II thoracoabdominal aortic aneurysms, 34 (35%) had aortic dissection, 19 (19%) were nonsmokers, 40 (41%) exsmokers, and 39 (40%) active smokers. Before operation, 55 (56%) had chronic pulmonary disease with respiratory failure developing in 58% (p = 0.0005 versus no chronic pulmonary disease, 10/43, 23%), and of the 26 patients in the lower quarter of forced expiratory volume (1 sec) (FEV1 less than or equal to 1.45 L) respiratory failure developed in 61% (p = 0.035). In-hospital survival was 98% and 83% (p = 0.008), respectively, and cumulative survival at 6 months by Kaplan-Meier analysis was 96% and 80% (p = 0.004, log-rank test), respectively, for patients without respiratory failure (N = 56/98, 57%) and with respiratory failure (N = 42/98, 43%). On univariate analysis, the following were associated with respiratory failure (p less than 0.05): FEV1, FEV1% predicted, FVC, FEF25, FEF25% predicted, FEF25-75, FEF25-75% predicted, PaCO2 Pao2, symptoms, smoking history, chronic pulmonary disease, cryoprecipitate volume, postoperative neuromuscular deficit, cardiac complications, reoperation for bleeding, renal complication, stress ulceration, postoperative creatinine level, postoperative dialysis, and postoperative encephalopathy. The independent predictors of respiratory failure were (p less than 0.05): chronic pulmonary disease, smoking history, cardiac and renal complications. In patients with chronic pulmonary disease, the only independent predictor was FEF25 (p = 0.030). These observations may be of value in selecting patients for elective operation.

Adult↗
PubMed1990

Spirometric standards for healthy nonsmokers female industrial workers in Egypt.

A groups of 213 Egyptian female industrial workers were selected from non dusty departments of the Nile Pharmaceutical company in America district. The subjects were asymptomatic, nonsmokers and not previously exposed to dust operations. All females workers were asked to complete a questionnaire on respiratory symptoms and then clinically examined. Those with no evidence of cardiopulmonary diseases were subjected to vitalograph spirometery. A prediction formulas based upon age and height were established for FVC, FEV1 and FEF 25-75%. Comparing our findings with the previous studies, the results revealed that our pulmonary measurements were lower than those obtained from the other similar studies. This was attributed to several confounding factors.

Adolescent↗
PubMed1990

[Characteristics of lung volume and expiratory flow seen in black Africans adults].

We have measured lung volumes, ventilatory flows, and the main thoracic dimensions in 65 Togolese adults aged between 25 and 55. We found that for Africans the total lung volume was 25% less and other lung volumes were 22% less than those for Caucasians. The difference in the total lung capacity was explained by smaller thoracic dimensions in Africans than in Caucasians of the same height; for the same TLC the residual volume was lower and the expiratory flows were higher in Africans than in Caucasians. The difference was most prominent on the proximal instantaneous flows giving a forced expiratory flow volume curve which was less straight and more concave at the end of expiration. Greater muscular strength, a larger diameter of the airways, and different alveolar development in the Africans may explain the differences.

Adult↗
PubMed1990

Histamine bronchoprovocation tests in subjects with gastro-oesophageal reflux disease.

The relationship of gastro oesophageal reflux (GER) with bronchial asthma has already been well documented in asthmatic subjects and it has been postulated that their asthma might have been caused by GER disease. Thus, it was planned to establish an association, if any, between GER and increased bronchial reactivity by histamine broncho provocation. The study was done in 25 GER disease patients and 15 controls. The difference in bronchial reactivity between the two groups was found to be significant (p less than 0.01). It was concluded that GER subjects expressed greater bronchial reactivity and it has been discussed that at a later stage of life they may be more prone to develop asthma.

Adult↗
PubMed1989

[The occurrence of circadian rhythm in respiration in healthy persons and in patients with bronchial asthma].

The authors examined in 69 healthy young men at times 0, 3, 6, 9, 12, 15, 18 and 21 hours values of FVC, FEV1, FEF50 a PEF. In 149 patients with bronchial asthma after the same time intervals FEV1 was assessed, whereby the interval at 3 a.m. was used as the mean of values at times 0 and 6 a.m. By analysis of variance the minima of the majority of investigated indicators were assessed in healthy subjects at 3 a.m. and 9 a.m. By cosinor analysis a statistically insignificant circadian rhythm for values FEC and FEV1 was proved in the entire group of healthy subjects and in subgroups of smokers and non-smokers. No rhythm was found in values of FEF50 and PEF. Rhythms in the ventilation values were detected in 40-60% of the subjects, in the remainder no rhythms were detected. In patients with bronchial asthma a significant circadian rhythm of FEV1 changes was found in groups with a morning or variable type of respiration. In groups with a stabilized ventilation a rhythm was detected but was not significant. In the group with an apparently irreversible obstruction no circadian rhythm was found.

Adolescent↗
PubMedDate not supplied

How useful is the FEV1%?

The ability of the forced expiratory volume for 1 second expressed as a percentage of the forced vital capacity (FEV1%) in identifying early airway narrowing was compared with that of the forced expiratory flow in the middle half of the forced vital capacity (FEF 25-75%), in two populations, young smokers and subjects with allergic rhinitis who are known to have early airway narrowing. FEV1% appears to be more sensitive, in differentiating these groups and in identifying abnormality. Among smokers, FEV1% detected abnormality in 19% while FEF 25-75% only in 7% and among the allergic subjects the former detected abnormality in 25% while the latter only in 19%. In longitudinal studies, the decline in pulmonary function in smokers is identified almost equally well by both parameters. Critical ratios (t) were 2.85 and 3.86 after 1 to 2 years and 7.32 and 3.97 after 3 to 4 years for FEV1% and FEF 25-75% respectively. A high degree of correlation exists between these two measurements in all the subjects. These findings indicate the usefulness of FEV1% in the detection of early airway narrowing and are of special interest to those engaged in a busy clinical practice, as the FEV1% is a quicker measurement to make, than the FEF 25-75%.

Adult↗
PubMed1989

Pharmacokinetic properties of sustained-release theophylline (Theolair-SR) in relation to timing of doses after low-fat meals.

Pharmacodynamic and pharmacokinetic properties of sustained-release anyhdrous theophylline (Theolair-SR) were similar when doses were given either immediately after or two hours after low-fat meals in children with moderate asthma requiring daily theophylline maintenance. Asthma and pulmonary function values were maintained and approached values for healthy subjects during both treatment regimens.

Adolescent↗
PubMed1989

[Pulmonary function tests in asthmatic children in treatment with tulobuterol].

The objective of the present study was to evaluate the effectiveness and tolerance of a new beta-2 agonist, tulobuterol, in children. Fifteen patients with acute asthma were studied, during a period of 21 days. Significant increase in forced vital capacity (FVC), forced expiratory volume in the first second (FEV-1), and forced expiratory flow 25-75% (FEF 25-75%) were observed after treatment with tulobuterol (p less than 0.01). Clinical improvement was evident as measured by a clinical-scale and a functional scale. The only side effect attributable to the drug was a tremor which was observed in three patients.

Adolescent↗
PubMedDate not supplied

Epidemiological measurement of bronchial responsiveness in polyurethane workers.

A shortened protocol was developed for the epidemiological measurement of bronchial responsiveness to methacholine without compromising sensitivity, power, precision or safety, and without distorting the numerical value of the PD20.FEV1 (the cumulative dose from a doubling incremental sequence which provokes a 20% decrement in FEV1). It was used in a survey of 254 polyurethane workers (83% of the eligible workforce) exposed occupationally to toluene diisocyanate. The mean duration of each test proved to be 38 min, it was well tolerated and 64 workers (25%) proved to be reactors. PD20.FEV1 appeared to be distributed unimodally. It was significantly correlated with questionnaire records of shortness of breath, chest tightness, and wheeze; and with pre-shift FEV1 and FEF25-75. Even the reactors requiring the highest dose of 640 cumulative inhalation units (1 unit = one 8.9 microliters inhalation of methacholine 1 mg.ml-1) to generate a PD20 measurement reported significantly more wheeze than the non-reactors. This indicates that the test had clinical meaning throughout its dose range of 0.3-640 units. No correlation was found between PD20 and individual changes in ventilatory function across the working shift, but mean shift changes were negligible and not statistically significant. PD20 was also found to be unrelated to age, sex, race, smoking, cough and atopy.

Asthma↗
PubMed1988

Respiratory mechanics in the aging rat.

1. Mechanical behavior of the respiratory system and pulmonary histopathology were investigated in young (8 months) and old (18 months) adult Wistar rats. 2. Respiratory mechanics were studied under static conditions and during both relaxed and forced expiration. Morphological studies consisted of descriptive light microscopy analysis of intratracheally-fixed, paraffin-embedded pulmonary tissue. 3. Old animals exhibited morphological emphysema and chronic bronchitis, decreased respiratory system (2.40 vs 3.42 cm H2O/ml) and lung (1.32 vs 2.30 cm H2O/ml) elastances, forced vital capacity (13.00 vs 14.32 ml), forced expiratory mean flows between 50 and 75% (35.67 vs 60.50 ml/s) and 75 and 100% (6.67 vs 17.67 ml/s) of forced vital capacity, and an increased respiratory system time constant (0.114 vs 0.082 s) in relation to young rats. 4. These results indicate that old animals suffer from a chronic obstructive pulmonary disease that resembles human pulmonary emphysema.

Aging↗
PubMed1988

Lung function changes following Legionnaires' disease.

Eleven out of thirteen patients hospitalized because of severe pneumonia caused by Legionella Pneumophila were evaluated over a period of 53 months. During the acute phase, all but one patient manifested severe hypoxaemia, needing either supplementary oxygen or, in the case of three, mechanical ventilation and one died. Following recovery, two patients complained of mild shortness of breath alone. However, most of the individuals showed subclinical mild to moderate ventilatory and/or gas exchange abnormalities a few months after discharge (less than 6 months). Despite the fact that some of these functional findings in part persisted at long-term (6-33 months), a significant overall improvement in lung function was noticed. The main pulmonary functional sequelae following Legionnaires' Disease might include a restrictive ventilatory defect, a low transfer factor and hypoxaemia.

Acute Disease↗