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G W Silvers

Publications and source records attributed to G W Silvers.

31 records · Page 2Linked to original sources

The right ventricle in chronic airway obstruction: a clinicopathologic study.

In men 40 or more years of age at death, the upper limits of normal (means plus 2 SD) cardiac ventricular weights were 69 g for the right ventricle and 203 g for the left ventricle plus septum. Right ventricular thickness, as usually determined at autopsy, was a relatively poor index of hypertrophy. When one ventricle hypertrophies as a result of stress, the other tends to enlarge simultaneously, even if no stress on it has been evident. Right ventricular weight correlated positively, although not strongly, with severity of emphysema and with the severity of clinical chronic airway obstruction. Correlations between right ventricular weight and pathologic changes in the airways were weak or absent, except that subjects with abnormal large airways, but normal small airways, showed improved correlation between severity of emphysema and right ventricular hypertrophy, compared with the entire series. There was no correlation between left ventricular weight and severity of emphysema. The electrocardiogram was very reliable in the diagnosis of right ventricular hypertrophy (corpulmonale) due to chronic airway obstruction; the chest roentgenogram was somewhat less sensitive in this regard.

Cardiomegaly↗

The significance of bronchial atrophy.

In a 4-year period, 196 lungs from patients with and without chronic obstructive pulmonary disease were examined postmortem for the presence of atrophy in segmental and subsegmental bronchi. As a result of simultaneous postmortem spirometry, cinefluorobronchography and partitioning of airways resistance, plus later assessment of anatomic emphysema, bronchial atrophy emerges as only one of at least three factors usually cooperating in production of abnormal expiratory airway collapse. In selected cases, bronchial atrophy appears to be an important contributor to expiratory airways obstruction.

Adolescent↗

Sonographic identification of lung maturation in the fetal lamb.

Ultrasound evaluation of fetal lung development in utero could be a noninvasive method for frequent monitoring of the state of pulmonary maturity and predicting when parturition could occur with minimum or no risk of respiratory distress syndrome of the newborn. In cases of high-risk obstetric management in premature labor, this ability may be a particularly useful tool. To pursue this possibility, the lungs and livers of 13 living fetal lambs were successfully imaged with a modified clinical B-scanner under carefully controlled conditions; physiologic function tests on the excised lungs determined the state of pulmonary maturity. In eight cases, maturity or immaturity was correctly identified by sonographic criteria. The results wer ambiguous in four cases. One case of immature lung was incorrectly identified as mature. The trends established in these animal studies appear promising and with refinement may form the basis for sonographic assessment of fetal lung maturity in a clinical setting.

Animals↗