38 Berliner klinische Wochenschrift, 1877, p. 159.
II. STRUCTURAL DISEASES OF THE LIVER.
Hyperæmia of the Liver.
DEFINITION.—An abnormal quantity of blood in the liver, constantly present, constitutes hyperæmia or congestion. During the period of repose there is less, but during the period of activity more, blood circulating in the liver, but the physiological hyperæmia is not, nor does it contribute to, a diseased state unless abnormal conditions continue it beyond the proper limits. The term hyperæmia, here used, applies to a pathological state in which various structural alterations grow out of the continual congestion of the blood-vessels of the organ.
CAUSES.—A physiological congestion of the liver ensues when the process of digestion is going on. The afferent vessels dilate, and not only more blood, but various materials taken up from the foods and products of digestion, many of them having directly stimulating effects, also pass to the organ. Frequent and large indulgence in food, especially if rich in quality and highly seasoned with spices, mustard, etc., the consumption of malt liquors, wines, and alcoholic fluids in general, the habitual use of strong coffee and tea, gradually induce a state of hyperæmia. If to the consumption of a large quantity of highly-stimulating food there is added the mischief of insufficient waste, the danger of congestion of the liver is the greater. Persons addicted to the pleasures of the table are apt to pursue sedentary lives, and hence, besides the inappropriation of the material digested, the process of oxidation is insufficient to burn off the surplus. A sedentary life further tends to make the circulation in the hepatic veins sluggish by lessening the number and depth of the respirations, and with the obesity developed under these conditions the propelling power of the heart is diminished by fatty degeneration or fatty substitution of the cardiac muscle. Disease of the semilunar ganglion, the solar plexus, and of the splanchnics under circumstances and of a nature not now well understood may cause dilatation of the hepatic vessels.
Suppression of a long-existing hemorrhage from piles and from the uterine system has caused hyperæmia of the liver. Evidences of hepatic congestion are comparatively common about the menstrual period in consequence of the tardy appearance of the flow, of its insufficiency, or of its sudden suppression. There is a form of jaundice known as icterus menstrualis, and attacks of hepatic congestion are not uncommon at the climacteric period.
The most important causes of hyperæmia of the liver are mechanical, and consist in obstruction to the circulation in the ascending vena cava from disease of the heart or lungs. Dilatation of the right cavities, incompetence of the tricuspid, and stenosis of the mitral orifice are the usual cardiac changes leading to congestion of the liver. The same effect, to a much less extent, however, is produced by any cause which weakens the propelling power of the heart, as myocarditis, pericarditis, etc. Amongst the pulmonary lesions obstructing the venous circulation are emphysema, interstitial and croupous pneumonia, effusions into the pleura, intrathoracic aneurisms or tumors, etc. It should not be forgotten that effusions into the left pleura, as was demonstrated by Bartels39 and confirmed by Roser,40 so push over the mediastinum toward the right and bend the vena cava in the same direction, just as it emerges from the opening in the diaphragm, that the circulation in this vessel is impeded, and consequently congestion of the liver induced.
39 Deutsches Archiv für klin. Medicin, Band iv. p. 265.
40 Archiv der Heilkunde, Band vi. p. 40.