Healing by Second Intention. Granulation. When a wound has caused destruction of tissue, or when a simple incision is left exposed to the air, the breach is filled up by new tissue through the process known as granulation. The superficial layer of lymph thrown out on the raw surface becomes oxidized and degenerates into pus, while the deeper layers become solid, fibrillated, the seat of cell growth, and are finally transformed into a fibrous structure. New bloodvessels form in loops in the developing lymph and constitute the bright red granulation-points which cover the raw surface. The fibrous tissue into which the lymph is transformed undergoes gradual contraction in development, and thus, day by day, the edges of the adjacent healthy skin are drawn in, so as to cover the wound more or less perfectly, and a slight scar only is left when healing has been accomplished.
Granule Corpuscles and Masses. This is another degenerative transformation in lymph and, is seen mainly in inflamed glands and brain and lung tissue. The cells found in the exuded lymph are made up of granules ¹⁄₁₀₀₀₀ inch in diameter, and besides these, large, irregularly shaped masses of granules are extended along the capillary bloodvessels. After the lymph has coagulated these granular masses soften and liquefy preliminary to reabsorption and removal, and the restoration of the tissue to a healthy condition. When in excess this softens and disintegrates the tissues, leading to permanent loss of substance. See granular degeneration.
Interstitial Development of Lymph into Tissue. This is equivalent to what takes place in the formation of the sac of the abscess or of granulation-tissue. The liquid lymph in coagulating, becomes fibrillar, and the cells and nuclei of the adjacent tissue, having an abundant supply of blood and nutriment, multiply first as simple, rounded embryonic cells, then deposit around them new tissue, becoming elongated, spindle-shaped, branching, etc., and thus get imbedded in a fibrous material of their own formation. These new formations are usually of a low type of organization, like white fibrous tissue or bone, and hence, although breaches in the higher structures like muscle, nerve, gland, skill, are filled up, it is usually only by the drawing together of the remaining healthy parts by these new formations without the restoration of any of the original tissue which has been destroyed. The cicatrix (scar), alone is made up of new material.
Lymph developing in this way may undergo any degeneration to which normal tissues are subject. Thus it may undergo black pigmentary (melanotic) degeneration, it may become impregnated with lime-salts (calcified), it may wither up into a hard gelatiniform or horny mass, or it may undergo fatty degeneration.
Fatty degeneration is the most common form, and consists in the excessive deposit of fatty granules, first in the cells which are in excess or badly nourished, and next in the adjacent tissue, the normal elements of which are replaced by fatty granules.
Softening is an almost constant result of inflammation. The exudate infiltrates and separates the tissue elements, destroying their cohesion; the liquefaction of these elements impairs this still further, and the more or less perfect transformation of the tissue into embryonic tissue entails the loss of its rigidity and power of resistance. Thus the inflamed brain-tissue may become a mere pulp, and the inflamed bone may be cut with a knife.
Ulceration is closely allied to softening. On the surface of a sore there is an excessive exudation of lymph, which loosens and disintegrates the layer of lymph that is already in process of development, and also a part of the tissue beneath. The cells in these parts fail to develop naturally and to build up good tissue; they become fatty, die, and together with the tissue in which they lie, break down and pass off as a pulpy debris. Thus the sore constantly deepens and widens, or at least refuses to contract and heal. It is usually the result of bacterial infection.
Gangrene or death of a part is another effect of inflammation. It results usually from the cutting off of the blood supply through the obstruction of the bloodvessels; by the pressure of excessive exudation in unyielding structures, as in bone, or under the hoof; by implication of the inner coats of the bloodvessels in the inflammation, when the contained blood will clot and obstruct them; or by blocking with the blood clots that have been formed at a distance and washed on in the blood current to be arrested when they reach vessels too small to admit them. Like suppuration, gangrene is associated with and often caused by a bacterial growth. The dead mass remains as an irritant, and is slowly separated by the formation around it of embryonal tissue, granulations and pus. A second form is molecular gangrene, in which the cells and minute elements of the tissue die, and are cast off, leading to phagedenic (eating, extending) sores, as noted above under Ulceration. When gangrene occurs on an exposed surface, that may be altered from the normal color into shades of yellow, brown, green, red, or black, according to the amount of blood and the stage of decomposition, and may be cut without pain, if the subjacent parts are not pressed upon; it may be soft, may pit on pressure, may crackle under the hand from the evolved gases of decomposition, and may be covered with blisters (phlyctenæ) with red, grumous liquid contents (moist gangrene); again, it may be white, as after freezing, or it may be dark colored, dry, and horny, as from ergotism (dry gangrene).
FEVER.
Definition. Symptomatic. Idiopathic. Symptoms. Contagion. Incubation. Premonitory symptoms. Chill, rigor. Reaction, hot stage. Defervescence. Crisis. Lysis. Natural temperature. Fever temperature. Retention of water in the system. Production of waste materials. Typhoid condition. High fever, low, hectic. Treatment in vigorous subject, in weak one. Regimen. Solipedes. Ruminants. Carnivora. Drink. Rest. Clothing. Air. General and local bleeding. Cupping. Warm baths, tepid, compresses, derivatives. Cold. Diaphoretics. Laxatives. Diuretics. Sedatives. Alkalies. Antipyretics. Stimulants. Tonic refrigerants. Tonics. In low fever. No depletion. Judicious elimination. Stimulants. Refrigerants. Antiseptics. Diet. Local treatment of inflammation. Cold. Astringents. Antiseptics. Warm applications. Stimulating embrocations. Blisters. Firing. Massage. Suppuration.