Causes: Mechanical injuries, falls, blows, kicks, degenerations,
amyloid, fatty, granular, congestion, neoplasms, glanders,
tuberculous, myomatous, microbian infection. In the horse, disease of
liver, heart, lungs, hepatic artery, portal vein, degenerations
following overfeeding, idleness, foreign bodies, arsenic, phosphorus,
parasites, violent movements in colic, running, draught, leaping. In
the dog, pampering and traumatism. In cattle forced feeding,
emaciation, microbian infection. In birds, tubercle, tæniasis,
microbian infection. Lesions: extravasation, intracapsular, or through
capsule into the peritoneal cavity. The extravasation bulges of a deep
black, covering a dark softened, pulpy, hepatic tissue, with light
colored fatty tissue around. Clots may be stratified from successive
bleedings. Liver usually enlarged. Symptoms: onset sudden, or preceded
by stiffness, soreness and other signs of hepatic trouble. Extensive
rupture, entails weakness, unsteady gait, perspiration, pallor of
mucosæ, small weak rapid pulse, palpitations, dilated pupils, rolling
eyes, amaurosis, tremors, convulsion in case of survival, coldness,
œdemas. Death in five hours to five days. Risk of relapse in
recovering cases. Treatment: rather hopeless, rest, laxative, ergot,
ferric chloride, tannic acid, witch hazel, cold water, snow or ice to
right side. In meat producing animals fatten.
_Causes._ Hemorrhage and rupture of the liver are closely correlated to
each other, the accumulation of extravasated blood in the parenchyma in
the one case leading to over distension of the capsule, and the
laceration of this capsule and of the adjacent substance of the liver
occurring in the other as a mere extension of the first. They usually
occur as the direct result of mechanical injury (falls, blows, kicks)
acting on a liver already softened and friable through disease. These
predisposing degenerations may be amyloid (Caparini, Johne, Rabe), fatty
(Julien, Gowing, Adam, Siedamgrotzky), granular softening, hepatitis or
congestion (Zundel), glander neoplasms (Mathis), tubercles, angiomata
(Trasbot), microbian infection (Stubbe), tumors (Brückmüller).
In the horse predisposing conditions may be found in diseases of the
liver, heart or lungs, in embolism of the hepatic artery (Wright), in
obstruction of the portal vein (Pierre), in infarction of the liver, in
degeneration with softening, in sarcomatous, melanotic, glanderous or
cancerous deposits in its substance, in degenerations consequent on over
feeding, idleness, congestions, on the penetration of husks of grains
into the liver substance, on arsenical or phosphorus poisoning. The
presence of flukes, echinococci and other parasites may also cause
congestion and softening. To the _immediate_ or _traumatic_ causes above
named may be added the violent movements attendant on a severe attack of
colic, and violent exertions in running, draught, leaping, etc.
(Friend).
In the =dog= we must recognize all the pampering conditions which
predispose to congestion and degeneration, together with more direct
operation of kicks, blows, falls, fights, over exertion, etc.
In =cattle= a forcing regimen is especially predisposing, and yet the
loss of vigor resulting from a diametrically opposite treatment, must be
accepted as an occasional cause. Stubbe found in emaciated cows miliary
hemorrhagic infarcts of a dark red color which gradually extended to an
inch or more in diameter. These he traced to microbian infection coming
by way of the chronic intestinal lesions which are common in old cows.
The final result of such infarctions was loss of hepatic substance and
the formation of cicatricial tissue with a marked depression on the
surface of the organ.
In =birds= fatal hepatic hemorrhages occur in connection with local
tubercle (Cadiot), tæniasis of the liver, or microbian infection.
_Lesions._ The hemorrhage may take place into the substance of the liver
only, or the capsule may be lacerated so that the blood escapes into the
peritoneal cavity in considerable quantity.
In the _horse_ it usually occurs in the right or middle lobe, rarely in
the left. There may be one or more hemorrhagic effusions varying in size
from a cherry to a duck’s egg, or even an infants’ head (Lorge). This
projects from the surface of the organ and its deep black contrasts
strongly with the white of the adjacent capsule. When laid open the
hepatic tissue is seen to be softened and pulpy, and its dark color
forms a striking contrast with any surrounding fatty liver. Any form of
degeneration may be revealed on microscopic or chemical examination. Not
unfrequently small clots of blood form under the capsule raising it in
the form of little sacs. Such clots are usually stratified indicating a
succession of small hemorrhages.
When the capsule is torn, the lesion may extend from one surface of the
organ to the other, and the edges, smooth, uneven or fringed, are united
together by a blood clot.
In case of hemorrhagic infarcts the lesion usually has a distinctly
conical outline corresponding to the vascular distribution. These are
especially characteristic of cases supervening on heart disease.
The volume of the liver is usually increased and the weight may reach 30
lbs. (Schmeltz), 34 lbs. (Lorge), or even 66 lbs. (Trasbot).
In _other domestic animals_ analogous lesions are found modified largely
according to the size of the subject.
_Symptoms._ These may develop instantaneously without any marked
premonitory indication. In other cases tenderness on percussion over the
liver, stiffness or groaning under sudden movements or turning, arching
of the back, hanging of the head, slowness in rising, costiveness,
slight transient colics, and even icterus may have been detected on
close observation. The symptoms of actual rupture are essentially those
of internal hemorrhage. The animal becomes weak, or unsteady upon its
limbs, perspires, arches the back, and shows a marked pallor of the
visible mucosæ. The pulse is small, thready, weak and accelerated, and
the heart beats violent or palpitating. The percussion dullness over the
liver is extended (Weber), the loins become insensible to pinching, and
there may be some distension of the abdomen. Dilatation of the pupils,
retraction or rolling of the eyes, amaurosis, tremors of the muscles of
the neck, lying down, or falling, and general convulsions may precede
death. This may occur in a few hours or it may be delayed if the lesions
are restricted. In case of survival, coldness and œdema of the
extremities and sheath have been observed. The lesser hemorrhages may
terminate in recovery if there is no attendant incurable disease. In
anthrax, glanders, cancer, tuberculosis, septicæmia, etc., a favorable
issue is not to be looked for.
_Duration. Termination._ In severe cases a fatal issue may be expected
in from five hours to five days. In the milder cases which make a
temporary recovery there is great danger of a second hemorrhage from the
new vessels in the tissue undergoing organization or from the adjacent
degenerate liver tissue. The course of the affection may be altered by
such complications as arthritis (Dieckerhoff), pneumonia, pulmonary
thrombosis (Leblanc), enteritis or peritonitis (Cadeac).
_Treatment_ is usually of no avail. Rest, and the administration of
laxatives and hæmostatics, have been especially recommended. Of the
latter, ergot by the mouth or ergotin subcutem, tends to contraction of
the blood-vessels and to check the flow. Ferric chloride is also used,
though apt to interfere with hepatic function. Tannic acid, hamamelis,
and other astringents may be used instead. Cold water, snow or ice
applied to the right hypochondrium may act as a check to the hemorrhage.
Unless in purely traumatic cases in an otherwise healthy liver, a
recovery is at best temporary, and the already degenerate liver is
liable to relapse at any moment. In horses and dogs, therefore, recovery
is by no means an unmixed good. Meat producing animals that recover
should be prepared for the butcher.