Synonyms:—Pulmonary infarction; hemorrhagic infarction.
Definition:—A hemorrhage within the interstitial structure of the lung with no destruction of lung tissue.
Etiology:—An embolus, usually from valvular disease of the heart, ultimately within the pulmonary artery, occluding one of its branches, is the cause of this disease. Conforming to the branching and distribution of the artery the consolidation will be wedge-shaped in character, with its base against the pleura and its apex pointing upward and into the structure of the lung. Infarction takes place also from extensive capillary engorgement and stasis. Rupture of an abscess will occlude the pulmonary artery or its branches and permanently block the circulation and exclude the air from all pulmonary cells within the area of the distribution of the occluded branches.
Symptomatology:—The immediate occlusion of a smaller branch of the pulmonary artery will be followed at once by difficult and rapid breathing, pain in the region of the disorder, dizziness, fainting, cough, with the expectoration of a small quantity of blood or bloody mucus, ultimately, perhaps, delirium and convulsions. When a main branch of the artery is obstructed, death may be sudden and almost unannounced, as in some cases of heart disease. The pulse is rapid, small, feeble at first, but will increase in strength as the acute symptom's subside in a favorable manner.
Diagnosis:—It is difficult often to positively determine the existence of this condition. The sudden extreme pain in the chest, with no previous injury, the bloody expectoration, with fainting and sudden prostration, are all diagnostic. The pain and unconsciousness occurring together are not present usually in other conditions. The conspicuous physical sign is that of a sharply outlined consolidation.
Treatment:—Specific measures are hardly available. The same measures should be adopted with the patient as are suggested in pulmonary apoplexy. The pain must be relieved, and treatment directed to the cause of the difficulty. Subsequent treatment must be directed to the conditions as they arise, and every effort should be made to effect an absorption of the obstruction. If the area of consolidation is not too great, benefit will accrue from a careful management of the case.