Scandinavian journal of respiratory diseases最新文献

We studied the effects of resistive breathing in 10 patients with long-standing, severe disabling COPD. Small increases in inspiratory resistive load resulted in diaphragmatic fatigue and failure in all patients. Fatigue was detected using the frequency spectrum analysis of an EMG signal obtained with surface electrodes. Failure was defined as an inward displacement of the abdomen during inspiration, i.e. incoordination of thoracoabdominal motion. The patients trained for one half hour daily for 4 weeks, breathing into a simple device, where they inspired against a resistive load that produced some incoordinated breaths. After 4 weeks this load was increased, if possible, and another 4-week training period started. All patients improved with training, i.e. higher resistances could be tolerated without signs of fatigue and failure. In addition most patients claimed that training had helped them in their daily living; they were able to do more without getting short of breath. The device helped expectoration, possibly owing to the effect of the small expiratory resistance.

Closing volume (CV) was measured in 64 healthy subjects aged 18--76 years, in supine position, with a bolus (helium) technique in two ways: following a maximal (CV100) and a submaximal (=50% VC; CV50) inspiration from residual volume. With increasing age CV50 increased less than CV100 according to the equation CV100(%VC)-CV50(%VC)=0.13Xage-0.6(r=0.46, P less than 0.001), e.g. at 70 years of age CV100=32(%VC) and CV50=24(%VC). Therefore, during normal breathing elderly subjects to not presumably close airways at as high a lung volume as predicted from conventional CV-measurements. A strong correlation between CV50 and CV100 was found, CV50(%VC)=0.55XCV100(%VC)+5.3(r=0.90; P less than 0.001), thus allowing a more accurate prediction of CV50 from CV100 than from age. Neither smoking habits nor body position affected the decrease of CV with reduced inspired volume.

Mortality from respiratory diseases in Finland in 1955--1973 was investigated using the official statistics and original death certificates. Total mortality from respiratory diseases in men was significantly higher than in women. Total respiratory mortality in men has increased slightly since 1963, whereas in women it decreased between 1955 and 1963 but has since remained almost constant. Mortality from lung cancer increased in men constantly in the years 1955--1973, but this was not found in women. Mortality from obstructive lung diseases in men increased slightly between 1955 and 1969 but not since. This increase was recorded only for the elderly whereas the opposite trend was found in younger people. The number of deaths from pneumonia decreased between 1955 and 1963. After 1963 these deaths increased again but only in the older age groups. Mortality from pulmonary tuberculosis showed a steady decrease. In 1973 the autopsy rate was 80.6% in pneumococcal pneumonia, 65.6% in pulmonary embolism, 48.1% in bronchiectasis, and 47.0% in pulmonary tuberculosis, exceeding significantly the mean national autopsy rate which was 38.3%. This might mean that at least some of these respiratory diseases are underdiagnosed clinically as the performance of an autopsy seems to increase their relative proportion in mortality statistics.

Five patients were studied using a randomly assigned sequence of four inspired-air conditions during strenuous treadmill exercise for 10 min. The four inspired-air conditions were: (1) Cool, dry room air (CDA) at 23 degrees C with 3 mg of water and 7.3 cal of heat content/l, (2) over-saturated air (OSA) at room temperature containing 43 mg water and 16.3 cal/l, (3) hot, dry air (HDA) at 120 degrees C having 3 mg water and 24.4 cal/l, and (4) warm, humidified air (WHA) at 37 degrees C with 43 mg water and 34.7 cal/l. Using inspired-air CDA and OSA, all patients manifested exercise-induced asthma (EIA) while forced expiratory volume in 1 sec (FEV1) and maximal mid-expiratory flow (MMEF) decreased to an average of 81% and 63% of the baseline when breathing CDA and to 83% and 71% of the baseline when breathing OSA. With WHA, EIA was clearly prevented while the post-exercise FEV1 and MMEF were 101% and 103% of baseline, respectively. With HDA, the post-exercise FEV1 and MMEF were 95% and 86% of baseline, respectively. Analysis of variance revealed that the post-exercise pulmonary function changes had resulted solely from respiratory heat loss and not from water loss or from interaction of heat and water losses. These results indicate that exercise-induced asthma is associated with airway cooling incurred during exercise rather than airway dehydration.

We have studied the maximal expiratory flow volume curves with air and with an 80% helium-oxygen mixture, using 12 normal and 33 asthmatic children chosen according to clinical, functional and immunological criteria. In the normal children, the average delta Vmax (difference between the maximal flow in HeO2 and in air at corresponding lung volumes) was 49% and was similar from 60% to 20% of vital capacity. The iso flow volume (lung volume level at which the HeO2 and air flow volume curves intersect) was 3% of vital capacity. Eleven of the asthmatics were non-responders to the helium mixture (no significant differences in flow between HeO2 and air curves), five at 50% and 25% VC and six at only 25% VC. The other 22 asthmatics were responders, but nine of them showed a rise of the iso flow volume. Eight subjects showed no obstruction according to the flow volume curves in air; three of these had an abnormal response to the helium mixture. All the non-responders at 50% VC and half of the non-responders at 25% VC had a clinical history of recurrent infections. These results suggest, firstly, that when there is no history of recurrent infections, the site of obstruction in asthmatic children is mainly central. This does not exclude a coexisting peripheral obstruction which could persist after recovery of the central component. Secondly, by studying the HeO2 response at 25% VC, we can get more information than by measuring only the delta Vmax50 or iso flow volumes.

Two female patients with familial diffuse fibrosing alveolitis associated with oculocutaneous albinism are presented. A family study was carried out and two other female patients with oculocutaneous albinism and pulmonary disease were detected. Clinical, radiological and histological features are highlighted and the results of treatment discussed.

Serum angiotensin-converting enzyme (ACE) activity was studied in healthy controls, in 57 untreated sarcoidosis patients, and in 164 patients with other chest or lymph node diseases. The serum ACE activity of healthy persons was independent of sex, intake of meals, and smoking habits. There were no diurnal variations. Healthy children had a significantly higher ACE mean value than adults, whose ACE activity was not affected by age. The sarcoidosis patients had the highest ACE mean values, but those of patients with silicosis and asbestosis were also significantly elevated. Pulmonary cancer patients had decreased serum ACE activity, which was probably due to antimitotic treatment. Serum lysozyme (LZM) concentrations did not correlate with normal ACE activity, but the correlation between elevated ACE and LZM was significant in sarcoidosis and silicosis, and the trend was clearly the same for asbestosis. This indicates separate sources for these enzymes when ACE activity is normal, and a common source, i.e. macrophages, when ACE activity is increased. ACE production in certain diseases involving macrophages may be due to the bradykinin inhibiting effect of this enzyme.

Bronchial secretions from 207 children suffering from various pulmonary diseases and from 15 healthy controls were tested concentration of IgA, IgG, lactoferrin and lysozyme. The results obtained suggest that in many cases of chronic lung diseases in children the levels of lactoferrin and immunoglobulins, especially secretory IgA, are very low. In severe infections (cystic fibrosis, bronchiectases) significant increase of IgG concentration was observed.

Serum angiotensin-converting enzyme (ACE) was studied in 51 patients with early or newly diagnosed sarcoidosis. Only 45% of these patients had increased ACE activity when their diagnosis was established, which diminishes the diagnostic value of this enzyme measurement. On the other hand, ACE accurately reflected disease activity, and it proved a useful tool for assessing of need for corticosteroid treatment. Patients with acute sarcoidosis associated with erythema nodosum (EN) had low ACE activity compared with the other patients with active, but less acute disease. Serum ACE was not significantly correlated with blood lymphocytes or the immunoglobulins, but there was a positive correlation between the enzyme and serum lysozyme, which strengthens the hypothesis of both enzymes being produced by the epithelioid cells of sarcoid granulomas.

All patients newly diagnosed as bronchial carcinoma were studied during a 5-year period. There were 212 male and 61 female patients. A careful occupational history was taken and the occupations of the patients in 1950 were compared with the County's official occupational statistics of that year, and their chest X-rays were scrutinized for pleural plaques. A significantly higher proportion of metal workers and workers from the building industry was found among the patients, while agricultural workers were under-represented. Smoking habits did not explain the difference. The number of patients with pleural plaques was four times higher than expected. It is concluded that dust in certain occupations has an additive effect on the carcinogenic effect of smoking.