Different forms. Embolism with infarction. Embolism from arteritis.
Rupture of bloodvessel. Changes in color. Symptoms. Repair.
Hæmorrhage into the lungs may be: 1st. Petechial in infectious diseases.
2d. _interlobular_ as from ruptured vessels. 3d. _Infarction_ or
apoplexy. _Infarction_ results from embolism of a branch of the
pulmonary artery, which may in its turn be due to clots formed in a
diseased heart or in the systemic veins and carried to the lungs in the
blood stream. It may also result from inflammation of the inner coat of
the pulmonary artery. A virtual stasis occurs beyond the embolism, and
the blood filtering in through the anastomosing capillaries fills and
blackens the affected lobule. With rupture of a considerable vessel the
blood escapes _en masse_ and appears like black currant jelly. As it
ages it becomes granular and changes to a yellow color, or it may form a
necrotic mass enclosed in a cyst as in lung plague. The symptoms, apart
from the absence of respiratory murmur and resonance, are not
diagnostic. It may take months to undergo liquefaction and absorption.
Iodide of potassium, bitters and stimulating diuretics may be given.