Surface of localized pleural plaques quantitated by computed tomography scanning: no relation with cumulative asbestos exposure and no effect on lung function.

To evaluate if there is a relation between the size of asbestos plaques and the level of past exposure and pulmonary function, we measured the surface of localized pleural plaques found on high-resolution (HR) CT scan, using a computerized video display unit-imaging system, in 73 workers (mean age, 43.5 yr) who had worked from 23 to 27 yr in an asbestos-cement factory. Their estimated cumulative exposure to asbestos ranged from 16.4 to 98.7 fiber-years/ ml (mean, 26.3 fiber-years/ml). Lung function measurements included lung volumes, maximal expiratory flows, and diffusing capacity. A control group of 21 workers was examined by the same procedures. Plaques were detected by CT in 51 (70%) asbestos-exposed subjects and in none of the control subjects. The average calculated plaque surface was 47.9 +/- 61.7 cm2 (median, 22.1 cm2; range, 0 to 278.4 cm2). There was no relation between plaque surface and cumulative asbestos exposure (p = 0.24). In the 51 subjects with pleural plaques, the surface of the pleural lesions was not related to cumulative asbestos exposure, or to smoking history or time since first exposure. Neither the presence nor the extent of the plaques was correlated with lung function parameters.

Possibilities and indications for Nd-YAG laser and dilation therapy in the management of tracheal stenosis.

The possibilities for therapeutic bronchoscopy have rapidly expanded during the last decade. Several techniques can be used exclusively or complementary to each other: dilation therapy, Nd-YAG laser photoresection and endobronchial stent insertion. This armamentarium can be used in several forms of tracheal stenosis, both benign and malignant. In post-intubation injuries and other benign conditions it can be a definitive treatment. In neoplastic tracheal stenoses, these procedures allow the time needed for proper staging and sometimes surgical resection, or very valuable palliation in well selected patients with inoperable disease.

Corticosteroids contribute to muscle weakness in chronic airflow obstruction.

Twenty-one patients with chronic obstructive pulmonary disease (COPD) or asthma, admitted to our division because of exacerbation of their conditions and requiring intensified treatment with corticosteroids, underwent pulmonary function tests, tests of respiratory muscle function, measurement of quadricep strength, and a variety of anthropometric and biochemical measurements. All tests were performed the 10th day after admission. As expected, muscle strength and pulmonary function were interrelated. Surprisingly, the average daily dose of steroids taken in the previous 6 mo, which ranged from 1.4 to 21.3 mg (average 4.3 mg), was significantly related to inspiratory muscle strength (PImax) and a similar tendency was present for expiratory muscle strength (PEmax). Multiple regression analysis of the relationship between PImax and quadriceps force (QF) and steroid dose revealed that the average daily dose independently explained 32% of the variance in PImax and up to 51% of the variance in QF. These relationships were independent of the degree of bronchial obstruction estimated by percentage predicted FEV1. Other significant determinants were age, sex, and COPD for PImax and age, sex, and body weight for QF. The present study demonstrates that in patients with COPD or asthma, respiratory and peripheral muscle strength and steroid treatment are interrelated despite the relatively low doses administered. This observation imposes further limitations on the prolonged treatment of chronic airflow obstruction with systemic corticosteroids.

Amiodarone and the development of ARDS after lung surgery.

An evaluation of amiodarone as prophylactic treatment for supraventricular tachyarrhythmias after pulmonary surgery was stopped because of a high incidence of the adult respiratory distress syndrome (ARDS) after a pneumonectomy. Retrospective analysis of all cases of resection for pulmonary neoplasm in our hospital between 1987 and 1991 indicates that amiodarone may be implicated in the development of ARDS after lung surgery.

Transcarinal needle aspiration biopsy in the staging of lung cancer.

Lung cancer without distant metastasis often requires an invasive surgical procedure to document inoperability. In order to determine how often puncture biopsy was a valid substitute for a surgical procedure, we investigated the performance of endoscopic staging by means of transcarinal needle aspiration biopsy during rigid bronchoscopy. Eighty lung cancer patients with subcarinal lymph nodes visible on computed tomography (CT) scan were studied. Specimens were of histological quality (i.e. lymph node tissue) in 59 out of 80 (74%) patients, and showed malignant invasion of this lymph node tissue in 43 cases. Specimens of cytological quality (i.e. lymph node cells) were obtained in 13 out of 80 (16%) patients, and showed malignancy in 7 cases. Therefore, adequate evaluation of the subcarinal lymph nodes was possible in 72 out of 80 (90%) patients. In 50 of these 72, malignant mediastinal spread was proven, and further invasive surgical staging could be avoided. Subgroup analysis showed that this outcome tended to be more likely in patients with abnormal endoscopic appearance of the main carina, with locally extensive tumours, and with nonsquamous histology. These results indicate that transbronchial needle aspiration biopsy of subcarinal lymph nodes can be a valuable alternative to more invasive surgical staging in patients selected by CT scan.

Predictive value of bronchoalveolar lavage in pulmonary sarcoidosis.

We investigated whether analysis of cellular composition (including lymphocyte subsets) in bronchoalveolar lavage (BAL) fluid at the start of follow-up in patients with untreated sarcoidosis has any predictive value for further evolution of the disease. The outcome was evaluated by the chest roentgenograms, the lung volumes, and the single breath diffusing capacity for CO (DCO) after 22 to 36 months. In contrast to the general belief, patients who improved radiologically had a significantly higher T4 cell count (as percentage of BAL lymphocytes) (p less than 0.02) and a higher T4-T8 ratio in the initial BAL sample (9.3 vs 3.2; p less than 0.05) than those whose chest roentgenogram showed deterioration or remained unchanged. Total cell count and the percentage of lymphocytes in BAL fluid were not different between both groups. The change in DCO at the end of the follow-up period correlated positively with the baseline BAL T4 cells (Rs = 0.44; p less than 0.05) and with the BAL T4-T8 ratio (Rs = 0.51; p less than 0.03) and negatively with the baseline BAL T8 cells (Rs = -0.48; p less than 0.04). In only three patients progression of the disease necessitated steroid therapy, and they all had a low to normal T4-T8 ratio in the initial BAL sample. Bronchoalveolar lavage was repeated at least once in ten patients. Improvement of the chest roentgenograms in these patients was accompanied by a decrease of the BAL T4 cell count (as percentage of lymphocytes) and of the T4-T8 ratio. We conclude that a high lymphocyte count, a high T4 cell count (as percentage of lymphocytes), and a high T4-T8 ratio in BAL fluid reflect an intense alveolitis at the time of the procedure, but they are not indicators of poor prognosis on which therapeutic decisions can be based.

Surgical treatment of bronchogenic carcinoma: a retrospective study of 720 thoracotomies.

Seven hundred and twenty patients with primary bronchogenic carcinoma were operated on at the Pellenberg Clinic, K.U. Leuven, Belgium, between January 1, 1970, and January 1, 1985. Almost 45% of the resections were pneumonectomies and 47% were lobectomies. Mortality was 6.9% and 2.9%, respectively. Patients with squamous cell carcinoma (Stages I and II) who underwent lobectomy or pneumonectomy had an absolute 5-year survival rate of 52.8% (93/176); it was 21% (4/19) in the T3 N0/N1 subgroup. Patients with adenocarcinoma who underwent a lobectomy had a 5-year survival rate of 49% (26/53) in the T1/T2 N0 group and of 27% (3/11) in the T1/T2 N1 group. Only 13.6% (3/22) of patients survived 5 years if a pneumonectomy had to be performed. Only 1 in 22 N2 patients survived 5 years after resection.

Combined asthma and alveolitis induced by cobalt in a diamond polisher.

A diamond polisher presented with a history of dyspnea, chest tightness, chills and weight loss related to exposure to diamond cobalt disks at work. Pulmonary function showed slightly reduced lung volumes, low normal diffusing capacity and a moderate bronchial hyperresponsiveness to histamine. Chest X-ray and cell count in bronchoalveolar lavage fluid were normal. After 3 months of non-exposure, a bronchial cobalt challenge test caused an immediate decrease in specific airway conductance and in vital capacity (VC) but not in FEV1/VC. After 6 h, chills, fever, tachycardia and crackles appeared along with moderate reductions in lung volumes. After 24 h, the bronchoalveolar lavage fluid showed 43% granulocytes, and there was a marked increase in bronchial hyperresponsiveness to histamine. These changes are interpreted as combined asthma and alveolitis induced by cobalt.

Alveolar T-cell subsets in pulmonary sarcoidosis. Correlation with disease activity and effect of steroid treatment.

Alveolar lymphocytes, obtained by bronchoalveolar lavage in 35 patients with sarcoidosis, were analyzed with monoclonal antibodies to lymphocyte subsets. Untreated patients had significantly higher percentages of Leu 3a (+) T helper-inducer cells (THI) and significantly lower Leu 2a (+) T cytotoxic-suppressor cells (TCS) within the alveolar lymphocyte population than did normal control subjects (p less than 0.002). The mean ratio of alveolar THI to TCS cells was 6.20 +/- 3.76 versus 1.44 +/- 0.54 in control subjects (p less than 0.002). Untreated patients had a percentual enrichment of THI cells among alveolar lymphocytes relative to blood (p less than 0.0002), whereas TCS cells in percent of lymphocytes were lower in alveolar lavage fluid than in blood (p less than 0.002). These shifts were not observed in the control subjects. Patients with high-intensity alveolitis (i.e., T cells constituted 28% or more of alveolar inflammatory cells) had significantly greater proportions of THI cells among alveolar lymphocytes than did those with low-intensity alveolitis (p less than 0.01). This percent of alveolar THI cells correlated positively with the number of lymphocytes and T cells in percent of alveolar cells (p less than 0.03), which both are indexes of disease activity. In untreated patients who were lavaged at least twice, a decrease in the THI/TCS ratio was found to accompany or precede radiologic and clinical improvement, but the initial THI/TCS ratio was not predictive of further evolution. Steroid treatment decreased the THI/TCS ratio with a marked increase in the proportion of TCS cells. These changes were independent of an effect on the number of alveolar lymphocytes.(ABSTRACT TRUNCATED AT 250 WORDS)

Cervical mediastinoscopy and anterior mediastinotomy in patients with lung cancer and radiologically normal mediastinum.

In the period 1975-1980, 1504 patients presented with lung cancer, 291 were presumably operable, and had no radiological evidence of mediastinal lymph node invasion. Two thirds (192 patients) underwent pre-operative surgical mediastinal exploration, and one third (99 patients) were operated right away. Of the 162 cervical mediastinoscopies, 16% had lymph node invasion (19.7% with right-sided, 10.6% with left-sided tumor); 28.9% of the 45 left-anterior mediastinotomies were positive. There was only one positive cervical mediastinoscopy of 46 cases with lower-lobe tumor, and no positive anterior mediastinotomy in 5 cases with left lower-lobe tumor. Mediastinal exploration yields, thus, a relatively higher percentage of positive results if the cervical mediastinoscopy is restricted to tumors affecting the right upper and middle lobes (25%), and if the anterior mediastinotomy is restricted to the left upper lobe (32.5%). A left anterior mediastinotomy should, thus, be recommended instead of cervical mediastinoscopy for tumors of the left upper lobe.

Roentgenographic lung changes, asbestosis and mortality in a Belgian asbestos-cement factory.

Annual chest radiographs, work history and mortality of 1,973 workers in an asbestos-cement factory were correlated with age and with duration and level of dust exposure. Degree of radiographic lung change was significantly related to fibre-years of exposure in the case of small lung opacities, pleural adhesions and pleural thickening. For 29 cases of asbestosis diagnosed between 1963 and 1977, a highly significant dose-response relationship was found. In comparison with national mortality rates, there was an excess of deaths due to cancer of the gastrointestinal tract, although there was no relationship to fibre-years.

Gas transport in a model derived from Hansen-Ampaya anatomical data of the human lung.

The anatomical data of the human lung published by Hansen and Ampaya are used in a model of gas transport in the lung. The Bohr dead space is calculated from solutions of a transport equation where diffusivity is given by an empirical formula obtained by Sherer et al. A satisfactory agreement is found with experimental data obtained from simultaneous washouts of H2 and SF6 for respiratory frequencies ranging between 15 and 60 min-1 and tidal volumes between 200 and 1,800 ml. The results support the idea that molecular diffusion is the main but not the only physical phenomenom which intervenes in gas mixing during breathing.

Transport of H2 and SF6 in the lung.

The dead spaces for hydrogen and sulfur hexafluoride are predicted from the solution of a partial differential equation, applied to Weibel's morphometric data of the lung, and including longitudinal convection and diffusion coupled with instantaneous radial diffusion. Traces of H2 and SF6 were washed in and out of the lungs of two normal subjects. Dead spaces for both gases were calculated from the wash-out curves by a least squares analysis. Prediction and experiment agree in the case of H2. The model overestimates the dead space for SF6 particularly for large tidal volumes and for high breathing frequencies. Several factors which can contribute to this disagreement are considered. From simulation experiments it is evident, that the dead space for SF6 is highly sensitive to factors which influence molecular dispersion in the region of respiratory bronchioles. Cardiogenic mixing and some sort of flow-dependent mixing in this zone cannot be ruled out. However, the experimental data can also be explained by choosing another set of morphometric data for the alveolated airways.

[Post-traumatic bronchial stenosis (author's transl)]. / Post-traumatische bronchusstenose

The authors have performed plastic reconstruction of a bronchus in a 16 years old patient, 6 1/2 weeks after rupture of the right stem bronchus. This had occurred during a blunt trauma to the thorax. In the acute phase the patient appeared completely cured by suction of the pneumothorax. Later occlusion of the bronchus with total atelectasis appeared. Respiratory function tests, blood gas analyses and pulmonary scintigrams were performed before and 12 weeks after the operation. The authors discuss the data from the literature pertaining to traumatic rupture of the bronchus in its acute phase and during progressive stenosis, for which surgery is warranted. Repair of the stenotic bronchus will make the lungs capable of assuming satisfactory hematosis.