(From Haemoptysis 4045 blood, and to spit). A spitting of blood; haeoptoe. By this term, however, is meant a bleeding from the trachea or the lungs; for blood from the nose and the stomach is often apparently spit. When from the veins of the lungs it is called perirrhexis: but this can scarcely, in any case, be ascertained.

Dr. Cullen places this genus in the class pyrexiae, and order haemorrhagiae, defining it a flushing of the cheeks; an uneasy sensation or pain, and sometimes heat, in the breast; a tickling of the fauces; a cough, by which blood of a florid colour, often frothy, is ejected by the mouth. He distinguishes five species:

1. Haemoptysis plethorua, when no external force has been applied, nor any cough or suppression of usual evacuation has preceded.

2. H.emoptysis viole'.vta, when from external violence.

3. Haemoptysis phthisica, where emaciation and continued debility follow.

4. Haemoptysis calcllosa, when with the blood calcareous concretions are thrown up.

5. Haemoptysis vicaria, when from the suppression of some accustomed evacuation.

Passionate, weak, and slender people, with long necks and flat breasts, or a sharp carinated sternum, gibbous or otherwise distorted, and those who while young were subject to bleed at the nose, are most subject to an haemoptysis.

An haemoptysis may occur, 1. From an accidental rupture or a wound of the vessels; but if the vessels are small, the patient quiet, and no previous disease exists in the lungs, there is little danger; but if large, the danger is considerable. 2. From tubercles or small tumours of an apparently scrofulous nature, contracting the vessels of the lungs, and consequently increasing the impetus on the other vessels, which in such constitutions are usually weak. This kind usually ends in phthisis. 3. From an ulcer in the lungs, forced up by coughing, and mixed with phlegm or pus; in which case the danger is great, as some large vessel has probably been eroded. 4. By anastomosis: this is said to be without danger, and often to relieve women whose menses are suppressed; but the existence of an anastomosis is in this case doubtful. It is more properly metastasis.

Sometimes the bronchial artery is ruptured. If the orifice is small, the discharge soon ceases; for, by the stagnation of the blood in the cellular substance of the lungs, the artery is compressed, and the rupture closed: this blood is sometimes absorbed, at others it excites inflammation, which terminates in suppuration. It then reaches the bronchiae, and is by degrees spit up; but a hectic usually follows.

When the rupture happens in the pulmonary artery the discharge is sudden, and the blood more copious and florid than when from the bronchial artery; but without pain, and unmixed with phlegm. In this case the preceding symptoms are anxiety about the praecor-dia, difficulty of breathing, an oppressive undulatory pain about the diaphragm, flatulencies in the belly, a sense of heat in the sternum, salt taste in the mouth, coldness of the extremities, hoarseness, a dry tickling cough, etc. As these show a general stricture on the vessels, and a change in the balance of the circulation, so they are commonly the forerunners of a copious haemorrhage. When the discharge is from the bronchial artery, its ejection is not sudden, and its appearance is blackish, and somewhat thick; though a frothy cough attends, there are a pain and heat in the breast, with a sense of weakness there, during the disease, sometimes with a fever, which abates with each discharge of blood, and returns at intervals when the haemorrhage is stopped. Sometimes matter is mixed with, or follows after, the discharges. The distinction of these two cases is, however, difficult, and of little importance. It is of more consequence to ascertain whether the blood comes from the fauces, the nose, or the stomach. If from the fauces, either directly, or dropping from the nose, it is inconsiderable in quantity, and not always attended with any hawking; and though this is sometimes the case, the symptoms of haemorrhagia nasi, or inspection of the fauces, will assist the distinction. Blood, however, seldom comes from the fauces, but in consequence of local inflammation or scurvy. When a discharge of blood is from the stomach, it is brought up by vomiting; but patients can seldom distinguish between these two operations. In general, when from the stomach, the quantity discharged at once is more considerable, it is mixed with the contents of the stomach, and not the mucus of the lungs; and nausea has generally preceded. The pulmonary blood is usually florid; that of the stomach of a darker colour. Complaints of the lungs preceding the discharge, will show that a doubtful haemorrhage probably proceeds from that organ.

Spitting of blood, or rather the appearance of some blood with the sputum, is generally useful in pleurisies and peripneumonies; in the robust, a spitting of blood is not always dangerous, but in the tender and feeble the disease is seldom cured; if blood proceed from an ulcer, the event will be probably fatal.

The causes of haemoptysis are those of haemorrhage in general, viz. fever, with an alteration in the balance of the circulation, or increased impetus in consequence of obstruction; but this requires some elucidation. We have said, that, in the gradual evolution of the human body, the head is at first disproportionately large, and receives, for purposes we need not now explain, a large proportion of the vital fluid. In succession the chest expands, and receives in turn its additional quantity. Thus, in early youth, bleedings from the nose .are frequent; we next find similar discharges from the lungs. When, therefore, a tendency to plethora exists, those vessels yield which are most fully distended in the different periods. Haemorrhages from the lungs are,