Definitions. Relations to active hyperæmia. Redness. Heat. Pain.
Swelling. Forms: in vascular tissues: in nonvascular. Changes in
tissue elements. Death of cells. Cloudy swelling. Granular
degeneration. Cell proliferation. Karyokinesis. Embryonic cells.
Amœboid functions. Migration of leucocytes. Red cells escaping.
Changes in innervation. Vaso-motor disorders. Fever. Changes in
circulation. Contraction of capillaries, dilatation, rapid flow, tardy
flow, stasis, oscillations, thrombus, collecting of white globules in
periphery of current, migration of leucocytes, blood plates, and red
globules, massing of red globules, exudation, softening of the
capillary walls, nutrient artery more rigid and transmits more blood,
heart contracts more forcibly, increase of fibrine, increase of waste
products. Buffy coat, physiological causes. Microbes. Ptomaines.
Toxins. Chemiotaxis. Phagocytosis. Polynuclear and mononuclear
leucocytes. Exudates, unlike dropsies. Mucous exudate. Serous exudate.
Fibrinous exudate. Blood exudations. Croupous exudation. Chyliform
exudate. Results and Products. Resolution. Delitescence. Metastasis.
New formations. Suppuration. Pus microbes. Pus. Healing by 1st
intention. Healing by 2nd intention, granulation. Granule corpuscles.
Interstitial neoplasia. Degenerations in lymph. Fatty degeneration,
melanotic. Softening. Ulceration. Gangrene.
Inflammation has been variously defined as “perverted nutrition,” as a
“protective reaction of the organism against irritant agents” and in
other terms that express at once too much and too little, without
actually defining the morbid process. Older definitions dealt with the
manifest disorders of circulation, of innervation or of tissue change
too often exalting the importance of one set of changes at the expense
of another and thus giving in the main a one sided view of the morbid
process.
Some modern bacteriologists are inclined to refuse the title to any
morbid process that is not caused by the presence of microbes or their
toxic products. To them the changes occurring in an aseptic wound or in
a simple fracture in process of healing are purely reparatory and
partake no more of the nature of inflammation than do the developmental
changes in the growing embryo. While to a large extent true, this
exclusive view implies exceptions, since if the chemical poisons derived
from the bacteria can develop inflammation, the same must be admitted as
possible for chemical irritants drawn from other sources.
As a matter of fact inflammation, occurring as it does in very different
tissues, vascular and nonvascular, fibrous, cellular, parenchymatous,
etc., and in connection with a great variety of irritants, must be held
to include a large group of morbid processes, bearing to each other a
strong family relationship and resemblance, and yet differing in many
important details. Each irritant (heat, cold, electricity, chemical
irritant, incised, punctured, lacerated or contused wound, rupture,
fracture, foreign body, parasite, microbe, toxin, etc.,) has its own
special character and mode of irritation; each tissue has its own
special method of succumbing or reacting and its own amount of blood
supply; and each system and organ has its own native or acquired power
of resistance and reaction.
Inflammation agrees with active hyperæmia in the tendency to dilation of
the vessels and an increased flow of blood to the part or if the
irritated part is nonvascular like the cornea or articular cartilage,
then to the parts adjacent. It differs, however, in the more active cell
proliferation, and in the nature of the liquid transudation which is
richer in albumen fibrine, cells and phosphates. Abstractly the inflamed
part retains very active vital processes, trophic and exudative, but
these, are largely changed from the normal and are, it is claimed,
perverted, yet they preside over the processes of cell growth and decay,
the removal of injured or useless tissue, and later, over the building
up of new material, and repair of loss. Active hyperæmia on the other
hand is mainly a circulatory disorder, and when it advances so as to
determine changes in the cells and tissues it is held to have merged
into inflammation.
The term inflammation (from inflammo, I set on fire), is suggestive of
the local heat of the inflamed part, just as fever (febris) indicates an
elevation of the temperature of the body at large. Celsius enumerated
the features of rubor, calor, dolor and tumor (redness, heat, pain and
swelling) which have come down to our own time as at least suggestive of
inflammation. But any diagnosis, based on these alone, would be today
woefully inadequate. Redness occurs in the transient blush, heat in the
febrile state, though no inflammation can be recognized, pain is present
in neuralgic and other nervous affections, and swelling in dropsy and
tumor. On the other hand redness is entirely absent, for a time, after
the outset of inflammation in nonvascular tissues (cornea, articular
cartilage), the heat of the inflamed part may be actually lowered when
there is much exudation around the capillary vessels and lessened flow
of blood, pain may be absent in some circumscribed inflammations of the
lungs, and swelling is not at first visible in the inflamed cornea or
compact bony tissue. These phenomena which are so common in inflammation
and, in general so characteristic of it, cannot therefore be accepted as
infallible evidence of its existence, nor can their absence be held as
absolutely implying its nonexistence.
=Forms of Inflammation.= This morbid process might be divided almost
indefinitely according to the organ invaded, the cause, and type, yet it
will be more convenient to deal with it generically and notice
=inflammation in nonvascular and vascular tissues= respectively, and the
different types of =granular degeneration=, =exudative inflammation= and
=croupous inflammation=. It will be requisite further to notice an
=acute= and a =chronic= type.
By dealing first with the changes in the anatomical elements of the
tissues and in the innervation, we shall virtually cover the phenomena
observed in nonvascular tissues, and later the changes in connection
with the circulatory system will give the additional characteristics of
inflammation in vascular tissues.