If the patient be seen during its continuance, there is little chance of mistaking the two. If he have not been seen till afterwards, the persistence of cough, with a few blood-stained sputa or clots of blood surrounded by frothy mucus, decides in favor of hiemoptysis; the appearance of black altered blood in the stools proves it to have been hzematemesis, especially if hemor rhage by the mouth have entirely and at once ceased; it can only get into the stools by being swallowed, when it comes from the lungs. Both conditions may be simulated by blood from the back of the nares trickling down into the oesophagus or the trachea; but here epistaxis indicates its source.
Hemorrhage from the lungs is associated with four different conditions of disease; (a) phthisis, and more rarely bronchitis ; (b) disease of the heart, especially with mitral regurgitation ; (c) aneurism ; (d) intra-thoracic fungoid growths.
a. In phthisis the quantity is very variable. It may be little more than a few streaks mixed with the purely bronchial expectoration of early phthisis. or with the muco-purulent fluid of its more advanced stages. This shed streaking, always an important symptom, is of more weight when appearing in a chronic affection of the lungs than when the expectoration consists of simple mucus. It may be impossible to assert positively in any given case that the lungs are entirely free from tubercles; yet when no trace of their existence is detected, the strain of a labored cough with scanty expectoration, especially if emphysema be present. and the mucous membrane congested, occasionally seems to give rise to a very slight amount of genuine hiemop tysis; and in such circumstances experience teaches that we may be justified in taking a more favorable view of the case. A cough of longer standing, with any opacity of the sputa, makes the appearance of blood to the very smallest amount a serious and alarming symptom.
It may be in very considerable quantity. while yet the disease has made comparatively little progress. In these circumstances, it causes obstruction to the passage of air through the tubes, and its particular locality may be traced by the sounds heard with the stethoscope at or near the apices of the lungs. In some rare instances, when it is very abundant, coming, perhaps, with a sudden gush, it proceeds from the erosion of a vessel in a vomica or abscess ; the other signs of phthisis are then well marked.
• The blood is at first always florid, and except when in very great quantity, also frothy; it becomes scanty and brown, or blackish, as the attack is pass ing off, when no more is poured out, and that which remains in the tubes is gradually being got rid of by expectoration.
b. In disease of the heart the amount is seldom or never great. and it is more variable in appearance. partly florid and frothy, partly mixed with darker clots, which generally indicate the existence of what is called apoplexy of the lungs. The blood is mixed with mucus or. muco-pus, according to the pre vious condition of the patient, as suffering more or less from bronchial irrita tion. Dyspncea is its invariable precursor, from the retardation of the passage of the blood through the lungs ; and this very frequently gives rise to (edema of the lung, bronchorrhcea, or bronchitis. The essential condition is one of obstruction to the onward current. as the blood enters or leaves the left ven tricle of the heart ; and the effect becomes most marked when this obstruc tion is caused by a backward flow of blood through the mitral.oriflce, in con sequence of which a double supply of blood is thrown upon the pulmonic veins. The examination of the heart ought to leave no doubt as to this cause of hemorrhage, and sometimes auscultation and percussion indicate with great precision its exact seat.
c. In aneurism the gush of blood is generiilly great, sometimes terrific, fol lowed by almost instantaneous death. • This is what we should expect from the very nature of the disease ; because, though partial hemorrhage may occur from erosion of lung tissue, by pressure, or from partial obstruction of vessels, in by far the greater number, the blood comes from actual bursting of the sac. The indications by which aneurism may be discovered will be afterward con sidered. (See Chap. XIII., Diseases of Bloodvessels.) d. In fungoid growths the blood is never brought up in any quantity. It has sometimes very much the same appearance as that caused by disease of the heart, and then it would appear to be the result of pressure and obstruc tion; more frequently it is seen as small clots, or as a sanions discharge, or it has the appearance of currant jelly. The diagnosis of intra-thoracic tumor will be afterwards discussed, as one of the forms of disease of the chest.