Bronchogenic
Carcinoma
Bronchogenic carcinoma accounts for about one third of all
cancer deaths in men and is becoming increasingly common in women. It commences
in most patients in the mucous membrane lining the larger bronchi and is
therefore situated close to the hilum of the lung. The neoplasm rapidly spreads
to the tracheobronchial and bronchomediastinal nodes and may involve the
recurrent laryngeal nerves, leading to hoarseness of the voice. Lymphatic
spread via the bronchomediastinal trunks may result in early involvement in the
lower deep cervical nodes just above the level of the clavicle. Hematogenous
spread to bones and the brain commonly occurs.
Segmental
Resection of the Lung
A localized chronic lesion such as that of tuberculosis or a
benign neoplasm may require surgical removal. If it is restricted to a
bronchopulmonary segment, it is possible carefully to dissect out a particular
segment and remove it, leaving the surrounding lung intact. Segmental resection
requires that the radiologist and thoracic surgeon have a sound knowledge of
the bronchopulmonary segments and that they cooperate fully to localize the
lesion accurately before operation.
Conditions
That Decrease Respiratory Efficiency
Constriction of the Bronchi (Bronchial Asthma) One of the
problems associated with bronchial asthma is the spasm of the smooth muscle in
the wall of the bronchioles. This particularly reduces the diameter of the
bronchioles during expiration, usually causing the asthmatic patient to
experience great difficulty in expiring, although inspiration is accomplished
normally. The lungs consequently become greatly distended and the thoracic cage
becomes permanently enlarged, forming the so-called barrel chest. In addition,
the air flow through the bronchioles is further impeded by the presence of
excess mucus, which the patient is unable to clear because an effective cough
cannot be produced.
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