a. BACILLUS OF FRIEDLÄNDER. This is a short rod with rounded ends, often
merely oval, occurring in pairs, or chains of four, and under given
circumstances surrounded by a transparent gelatinous capsule. It is
ærobic, nonmotile, does not liquefy gelatine, nor sporulate, and in
gelatine stick cultures has a nail-like growth. This was found by
Friedländer, Frobenius, Weichselbaum and Wolf in the pulmonary alveoli
in a small proportion of cases of croupous pneumonia in man. The
cultures, injected into the lungs of animals, killed one dog (out of
five), six Guinea pigs (out of eleven), and thirty-two mice (all the
injected). Lesions were intense congestion of the lungs, seropurulent
pleural effusion, and enlarged spleen, while the bacillus swarmed in the
blood and exudate.
MICROCOCCUS PNEUMONIÆ CROUPOSÆ. First found by Sternberg in his own
saliva in health, and by Pasteur in the saliva of a rabid child.
Afterward found in the great majority of lungs affected with croupous
pneumonia in man, by Talamon, Salvioli, Sternberg, Fränkel,
Weichselbaum, Netter, Gamalei, etc. Later it was found in meningitis, in
ulcerative endocarditis, in arthritis, in otitis media, and in acute
abscess in man.
It is a _spherical_ or _oval coccus_, arranged in pairs, in fours, or
exceptionally in eights or tens. Lanceolate forms are the rule in the
blood of animals, and circular in artificial cultures. It stains readily
in aniline colors and by Gram’s method, grows in ordinary culture media,
at 37° C. in the absence of free acid, and in gelatine stick cultures as
small, white colonies along the line of culture, without liquefying the
gelatine. It dies in ten minutes at 52° C. (Sternberg). Its virulence
lessens in artificial cultures, but is restored by passing through the
body of a susceptible animal.
Injection into the lungs or trachea of rabbits, mice, sheep and, less
certainly, Guinea pigs, produced distinct fibrinous pneumonia filled
with the microbe. In dogs, subcutaneously, it caused abscess, but in the
lungs an acute fibrinous pneumonia which only exceptionally proved
fatal, recovery usually taking place in ten to fifteen days.
Klemperer induced immunity, sometimes lasting six months, by intravenous
injection of filtered cultures.
DIPLOCOCCUS PNEUMONIÆ EQUINA. First found by Schütz in the lungs of
pneumonic horses in 1887. It is an oval coccus arranged usually in pairs
or in threes or fours, and surrounded by a transparent envelope. It
stains in aniline colors but not by Gram’s method. It is ærobic and
grows in gelatine at ordinary temperature without liquefying it, and in
stick cultures forms a line of small, white, separate colonies which do
not coalesce by growth. Does not grow on the surface of the gelatine
around the puncture. Line cultures on agar are in colonies like minute
transparent droplets. In bouillon it develops long chains.
Inoculated on the rabbit, Guinea pig and mouse, it produced death with
pneumonic affections (hæmorrhagic congestion or inflammation), but it
failed to take in some of the rabbits and Guinea pigs. Chickens and pigs
proved immune. Injected into the horse’s lung or as spray into the
trachea it produced true croupous pneumonia. Fiedaler and others
obtained similar results. Peter has found the fæces of pneumonic horses
virulent, an important point in connection with disinfection.
Schütz found that 20 grammes of the culture, in an equal quantity of
boiled water, injected into the horse’s trachea, produced a rise of
temperature by two or three degrees, with rigors, cough, accelerated
pulse, elevated temperature, dyspnœa and prostration, but that this
subsided in a few hours. By repeating this every thirty-six hours, the
fourth or fifth would fail to produce a reaction and the subject proved
immune.
CADEAC’S DIPLOCOCCUS PNEUMONIÆ EQUINA. In the lungs of cases of
contagious pleuro-pneumonia of the horse Cadeac found a round
noncapsulated coccus appearing in pairs, or rarely in chains, and
staining by Gram’s method. It grew slowly in bouillon and agar at 37°
C., forming on the latter in twenty-four hours, a thick, whitish, oily
drop, which, as it grew larger, assumed a silvery whiteness, and dried
in the centre. In bouillon it precipitated a powdery sediment. The
reaction of the culture medium was unchanged. It lost virulence rapidly
in artificial cultures or by a heat of 50° C., and it died in ten
minutes at a temperature of 60° C. Virulence was long retained when
dried, or even in putrid material.
This proved infecting to the ass, rabbit and Guinea pig, while the cat
and white rat proved immune. Intratracheal injection of the dog produced
a transient pneumonia. The ass inoculated with the blood of the infected
rabbit died in three days, with a hepatized lung, pleurisy, and swarms
of the microbes in the lungs, blood and internal organs. Rabbits
injected intravenously had enlarged spleen, reddish exudate in the
serous cavities, urine stained with hæmoglobin, and lungs and kidneys
congested. With intratracheal injections the lesions were exclusively
pulmonary. The pulmonary lesions were less constant in the Guinea pig.
Weakened virus caused pulmonary lesions only without septicæmia.
It has been suggested that this coccus is at least closely related to
that of pneumo-enteritis of the horse.
_Symptoms._ The onset of pneumonia is not often seen by the
veterinarian, who is called in only after the cough, loss of appetite,
hurried breathing and rigor has revealed illness to the attendants.
Hence perhaps chill and rise of temperature have been placed among the
earliest symptoms. The symptoms are more violent in the racer, trotter
and other nervous animals. Trasbot positively claims, that considerable
pulmonary inflammation and even exudation have taken place before there
is any chill or rise of temperature. This is especially the case in the
heavy lymphatic races of draught horses, which often according to this
author perform their usual work for days after inflammatory exudation
has set in. A fair counterpart of this is found in lung plague of cattle
and it would indicate that both start from a local infection, which
gradually extends until the systemic derangement is induced. As usually
seen, and especially when it follows exposure to severe cold, a staring
coat or a shivering fit usher in the disease, the degree of the chill
bearing some ratio to the coldness of the air and to the future severity
of the malady. This may be accompanied by a small, dry cough, but
without any other marked sign of lung disease. With the access of the
hot stage the characteristic symptoms of lung disease are manifested, at
first resembling those of _congested lungs_, but less severe than those
given under that head. There is a distinct increase of the body
temperature; the visible mucous membranes are suffused with a blush; the
expired air feels hot upon the hand; the breathing, 30 to 40 per minute,
is short and accompanied by much lifting of the flanks—(_labored_); the
cough is deep as if coming from the depth of the chest, but not so hard
nor so painful as in bronchitis; the legs are placed apart, the elbows
turned out and the head protruded to facilitate breathing; the nose is
turned to an open door or window if any such is available; the
contraction of the muscles of the face, the dilated nostrils and the
retracted angle of the mouth give an anxious expression to the
countenance; the eyes are semi-closed; the pulse full but
soft—(_oppressed_)—, beats from 48 to 70 per minute; the bowels are
slightly costive, the urine scanty and high colored; the skin
inelastic—_hidebound_—harsh and dry, though sweats may bedew it in
parts; the loins insensible to pinching; and if there is any discharge
from the nose it consists only in a reddish—_rusty_—colored mucus.
=Auscultation= and =percussion= complete the diagnosis. At the outset
the inflamed portion of lung, usually near its lower part, conveys a
_crepitating_ sound to the ear, but as consolidation extends the healthy
murmur and the crepitating râle are alike suppressed over the whole
extent of the hepatised portion around the margin of which a line of
crepitation betrays the limit of the advancing inflammation. A similar
line of crepitation encircles the hepatised mass even when the exuded
products are being absorbed and when the lung is being cleared up and
restored to its healthy state. Thus the advance of the inflammation, and
the progress of recovery can be equally followed by the crepitation
which, in the different circumstances, betokens active inflammation or
active absorption. When both lungs are involved the posterior parts are
chiefly implicated, while if the pneumonia is single it may attack the
anterior, median or posterior part, or the entire lung may become
consolidated. If hepatisation exists in the anterior part of the lung
the thick fleshy shoulder will forbid any satisfactory examination, but
if in the middle portion only, while the respiratory murmur is lost it
will be replaced by a strong blowing sound (bronchial respiration)
because the noise of the air rushing through the larger bronchial tubes
to the posterior healthy part of the lung is conveyed with greater force
to the ear through the consolidated lung tissue. This is audible from
the lower third of the chest to the upper limit of hepatization. The
respiratory murmur in the healthy lung is always louder than is natural.
=Percussion= confirms these results. Over the hepatised lung where no
respiratory sound remains, a dull, dead sound only is brought out by the
impulse of the fingers or closed fist, comparable to that obtained by
percussion over the muscular masses of the shoulder or haunch, and
forming a marked contrast to that obtained over the surrounding healthy
lung. There is not that tenderness on pressure in the intercostal spaces
which characterises pleurisy, but a sharp blow with the closed fist
leads to wincing and usually grunting because of the concussion to which
the diseased part is subjected. By increasing the force of such blows
the deepest parts of the lungs may be tested, since in this way dullness
due to consolidation of the deeper portions of the lungs may be detected
even though the superficial investing parts are healthy.
The nature of the symptoms will vary according to the extent and
character of the inflammation, from mild febrile reaction, with excited
breathing and slight crepitation, to the more severe varieties in which
the intensity of the symptoms are such as to threaten suffocation.
A marked feature of pneumonia in solipedes is that the patient
obstinately stands in one position and never lies down so long as the
severity of the inflammation lasts. The sharp crest on the lower border
of his breast bone compels the horse to lie on his side, and since in
this position the whole weight of the body has to be overcome in any
full dilatation of the chest, he cannot retain the recumbent posture
when any serious impediment to breathing exists. Hence it is that the
fact of a horse suffering from pneumonia having lain down and remained
so for some time is justly accepted as an indication of improvement.
_Progress and results of the disease._ The general symptoms above noted,
remain with more or less intensity throughout. After the first flush of
heat, on the occurrence of febrile reaction, the limbs become
alternately hot and cold, and in this the general surface partakes to a
less extent.
The tendency of pneumonia is to a crisis and recovery. Certain days have
been supposed to be critical and on the whole the third, seventh,
eleventh and fourteenth are those on which a favorable change is most
probable.
Among the more _favorable indications_ are the manifest abatement of the
high bodily temperature and febrile symptoms generally, the increasing
ease and regularity of the breathing, the greater force, distinctness
and slowness of the pulse, the permanent return of warmth to the limbs,
the softer and more elastic feeling of the skin, the recovery of
appetite, and above all, the turning of the nose from the open window or
the retention of the recumbent position for a length of time. These
symptoms will become more patent day by day, and the absorption of the
effused products and the clearing up of the lung may be traced by the
gradually decreasing area of dullness and of the circular line of
crepitation as ascertained by percussion and auscultation.
If on the contrary the disease takes an _unfavorable_ turn, some such
signs as the following will manifest it: Increasing rapidity and
embarrassment of the breathing; smallness and indistinctness of the
pulse, which is increased to perhaps 100 beats per minute; tumultuous
heart’s action, the impulse of which is strongly felt behind the left
elbow; a more laborious working of the flanks; frequent despondent
looking toward the flanks; pawing with the fore feet, lying down, and as
suddenly rising again; permanent coldness of the extremities; hanging
head with great dullness and despondency of expression; dull, sunken,
lusterless eye; hanging lower lip; leaden hue of the nasal mucous
membrane; convulsive twitching of the muscles of the surface; reeling in
gait, and extension of the crepitation over all the still pervious lung.
SUBACUTE PNEUMONIA. This term is employed to designate that subdued or
milder form of the disease which sometimes arises spontaneously and at
others follows the acute.
In this variety the characteristic symptoms may be much less marked and
the disease is less easily recognized. There is some acceleration and
quickness of pulse, lifting of the flanks and heat of the mouth and body
generally. There are alternations of heat and cold of the surface and
extremities, a rough, unthrifty coat, hidebound, a dull, listless moping
manner and the same symptoms on auscultation and percussion as in the
acute form.
The changes take place slowly but the disease may prove obstinate and is
often followed by permanent alterations in the lungs. Rheumatic
affections of the limbs, inflammation of the feet, and other diseases
frequently supervene during the course of this form of the affection.
The =terminations= of pneumonia are:—by =death=; =resolution= with
absorption of exuded products:—=splenisation=; =abscess=; =gangrene=;
permanent consolidation with organization of exuded products. The
disease will sometimes lapse into the chronic form.
=Death= is fortunately the least frequent issue. It may follow on
rapidly advancing and general congestion of the lung,—asphyxia; from
heart failure, the overworked organ becoming exhausted under the strain
of forcing the blood through the virtually impervious lungs; from
hyperthermia, the limit of bodily temperature 108°F. having been reached
or exceeded; or from collapse and exhaustion.
In =resolution= which is the most favorable termination the febrile and
other symptoms subside and the exudations in the effused lung undergo a
process of liquefaction and absorption until neither auscultation, nor
percussion nor even the examination of the lung after death will show
the slightest trace of the pre-existent disease. This is the most common
termination in single pneumonia in the horse.
=Splenisation= is that condition of lung already described under the
head of _pulmonary congestion_, and if affecting both lungs throughout,
necessarily destroys life by arresting the æration of the blood.
=Abscess.= Diffuse suppuration is very common in the stage of gray
hepatization. In this the affected lung becomes more or less extensively
infiltrated with pus limited by no distinct membrane like the pus of an
abscess, but exuding freely from the cut surface of the lung or escaping
from its interstices when it is pressed. It is preceded and in its early
stages associated with the formation of granular masses and corpuscles.
Its existence cannot be certainly ascertained though it may be surmised
when after hepatization of a portion of lung a _mucous râle_, a sort of
gurgling, is heard in the adjacent bronchium and an abundant
muco-purulent discharge takes place from the nose. It threatens
extensive destruction of lung tissue.
_Circumscribed suppuration_ or _abscess_ is infrequent though
occasionally met with in the horse and ox. In this case the excessive
exudation at one point liquefies and the surrounding lymph becoming
organized into a vascular membrane an abscess is formed. This may burst
into the bronchial tubes and be discharged by the nose. In less
favorable cases it makes its way toward the pleural surface and opens
into the cavity of the chest. It is impossible to detect the existence
of a pulmonary abscess though after it has burst into a bronchial tube
the existence of the cavity may be ascertained by the amphoric sound
heard on auscultation.
Animals may recover from such pulmonary suppurations or if they are too
extensive the consequent depletion may induce hectic and death.
=Gangrene= of the lung is happily rare and has appeared to be connected
with close, foul stables, previous ill-health, and work after the onset
of pneumonia. It is characterized by high temperature (106° to 108° F.)
by great dulness and prostration due to the poisoning of the nerve
centres, by weakness and unsteadiness, by complete loss of appetite, and
at length an intolerable fœtor of the breath as if from putrefying
animal matter. In rare cases recovery may take place, the dead portion
having become detached and expectorated.
=Consolidation= from =hepatization= is the condition in which the
inflamed lung is always found, in the second stage of the disease. The
lung has then the density and brownish red appearance naturally
belonging to the liver (_red hepatization_), which changes on the
occurrence of softening of the exuded products to a grayish hue (_gray
hepatization_). But after the subsidence of the acute symptoms, the
process of liquefaction and absorption is not always complete, a portion
of the exuded product becomes vascular, is developed into fibrous tissue
and remains permanently impervious to air. Such is the state of the lung
in many cases of _thick_ or _short wind_ in horses when these have
occurred as a sequel of pneumonia. A horse suffering in this way has the
breathing habitually accelerated and is thrown into a state of great
distress by any attempt to make him perform hard work such as galloping,
dragging a load up hill and the like. A _chronic cough_ may equally
accompany this condition.
=Pathological Lesions.= These differ according to the stage of the
disease. In the _first stage_, that of congestion the lung tissue is
engorged with blood as described under the head of =congested lungs=. As
early as 6 or 7 hours after artificial irritation, the alveoli of the
affected part are already filled by exudation and cell proliferation.
Until this has taken place the alveoli can still be distended by blowing
into the bronchial tube.
In the =second stage= the condition of the lung is that of =red
hepatisation=, so called from its resemblance in color and consistency
to the liver. There are gradations between congestion and red
_hepatisation_. In the earlier stages of the latter, the lung retains a
measure of its softness, elasticity and permeability to air, though it
is considerably firmer and less permeable than that which is in a state
of congestion and differs further from it in exuding from its cut
surface not a grumous, dark bloody pulp, but a clear straw colored
fluid. In the advanced _red hepatisation_ the lung is of a firm
consistency and granular liver like appearance. In color it varies from
a bright red to a dark liver hue, the darker shades being chiefly met
with in old animals or when the inflammation and fever have been intense
and prostrating. Varying shades are seen in different lobules of the
same lung. Its air cells are no longer pervious, it no longer crepitates
under the pressure of the finger, nor floats in water, and its
friability is such that it breaks down readily when the finger is thrust
into its substance. Its surface is distinctly granular from the
fibrinous plugging of the alveoli. Such a lung does not collapse when
the chest is opened but retains its bulk and shape and in some cases the
diseased portion may, by reason of the abundance of the exudation, be
really larger than the same portion of lung in a normal state of
dilatation. Its surface may thus retain the imprint of the ribs. Owing
to the stasis of the blood in the vessels a hepatised portion of lung
cannot be injected. The exudation which infiltrates the lung tissue and
obliterates the air cells contains in the vicinity of the bloodvessels
numerous granular masses and corpuscles and in the darker colored
portions blood globules, owing to the action of diapedesis the red cells
and the rupture of minute vessels. The smaller bronchial tubes stand out
white and empty showing that they have escaped the inflammatory action.
Hepatization usually extends from the anterior lobe or lower border
upward.
=Gray hepatization= is a sequel of the _red_ and presents the same
firmness, friability and usually the same granular aspect; the lack of
crepitation on pressure, and the higher density than water. From the cut
surface a fatty or purulent fluid exudes spontaneously, or in other
cases only when pressure is applied. The granular masses and corpuscles
have disappeared, and if suppuration is not so abundant as to prove
extensively destructive to lung tissue, that is gradually cleared up and
restored to health. This state is always a very perilous one.
=Abscess of the lung= sometimes met with in animals dying of pneumonia
shows a circumscribed area of inflammation and induration with the
liquid pus in the centre immediately surrounded by a vascular (limiting)
membrane. Abscess may be single or multiple though in the latter case it
is commonly a symptom of pyæmia.
In _gangrene of the lung_ the part may be in the dried condition of an
eschar; it may indicate gangrene only by its altered color, its
flaccidity, its fetid smell and the altered appearance of all its
microscopic elements; it may be denoted by a putrid softening, the
tissue easily breaking down into a stinking pulp of mixed fibrous and
granular materials; or lastly there may be merely a cavity with traces
of putrid contents, the dead mass having been detached, disintegrated
and expectorated.
_Modifications of the Blood and Distant Organs._
A marked feature of pneumonia is the destruction of red blood globules.
This is early indicated in the staining of the visible mucosæ by the
liberated hæmoglobin and by actual count they may be reduced in the
horse from 7,500,000 to 6,000,000 per cubic millimeter (Trasbot). There
is an increase of white globules, an absolute increase, not only in
ratio to the red. The hæmatoblasts are enormously increased especially
during defervescence. The fibrine (fibrine formers) is materially
increased; in the horse from 3.5 to 6.7 or 7.5 per 1,000 (Grehaut).
Albumen is diminished. Soda salts are increased. The bronchial lymphatic
glands are always congested, swollen and reddened with some serous
effusion. They may become the seat of inflammatory cell growth
(embryonic tissue) or even of suppuration. The abscess may open into the
bronchia or pleura. These are especially to be dreaded from their
tendency to implicate the inferior laryngeal nerve and induce roaring.
Pleurisy is inevitable when the inflammation reaches the surface of the
lung, hence hydrothorax is often present. Pericarditis and
hydropericardium are similarly met with. Endocarditis is occasionally
present and may be traced to strain of the valves of the laboring heart,
or to direct infection with the pneumonia microbe. Dilatation of the
right ventricle is common as a result of the obstructed pulmonary
circulation.
Fatty degeneration of the heart and congestions of the intestinal
mucosa, liver, kidneys, and spleen are further complications.
Finally laminitis and rheumatoid affections occur as complications.
_Treatment._ This must be adapted to the nature and condition of the
subject and to the character of the disease. A horse in vigorous
condition or with an acute type of inflammation may be greatly benefited
by an actively depleting treatment, whereas to the same animal in a low
state of health, or during the prevalence of an epidemic form of the
malady depletion may be destruction. It is not sought here, as is so
often done in the consideration of this disease, to ring the changes, as
to the probability of a change of type in disease, or a change of theory
on the part of physicians, having affected the practice of bloodletting.
True to our primary purpose of rendering the work eminently practical,
we shall first notice the general management applicable to all cases,
then the treatment of the two great types of the disease, acute
(sthenic), and subacute (asthenic), leaving to the enlightened judgment
of the reader to apply an appropriately modified system to that large
class of cases which occupy an intermediate position.
A pure airy box is first demanded, with the windows or doors toward the
south, or at least not turned in the direction of the prevailing cold
winds. The craving for pure air, so strikingly shown by the position
which the animal assumes, ought never to be ignored nor neglected. We do
not advocate the system of the late Professor Coleman who kept pneumonia
patients in open sheds exposed to all vicissitudes of temperature winter
or summer, and yet the fact that many recovered under such treatment as
well as under a more rigorous system, having been turned out into the
open fields amidst frost and snow, ought to open the eyes of all to the
incomparable value of fresh air in this disease. The box then must be
dry, cool and airy but without a cold exposure and without draughts of
cold air.
Next in importance to pure, cool air is the comfort of the patient. Any
tendency to chill, shivering, staring coat, or coldness of the surface
and extremities is to be counteracted as far as possible. One or more
blankets according to the condition of the patient and the temperature
of the atmosphere are valuable and for the same reason a hood may be put
on. Coldness of the limbs is to be met by active rubbing with the hand
or with wisps of dry hay and then wrapping up loosely in flannel
bandages. Some apply to the limbs ammonia and oil, spirits of
turpentine, and other stimulants and thus by a powerful derivative
action obtain an alleviation of the lung symptoms. For the same reason a
mustard poultice on the chest, or the hot wet rugs recommended for
congested lungs, often prove valuable in the earlier stages. Large
injections of warm water and the supply of warm gruels are not to be
neglected when they can be employed. Measures such as these directed to
check any chill and render the circulation free and uniform in the skin
and extremities, if adopted during the cold stages of the fever, will
sometimes succeed in bringing about a resolution of the pulmonary
congestion and warding off a threatened attack of pneumonia.
The diet should be of a non-stimulating and laxative kind. Bran mashes,
linseed, oatmeal, or other gruels, carrots, turnips, scalded hay, or
green food, if at the proper season, should be given in small quantities
so as not to satiate.
_Antiphlogistic Treatment._ Half a century ago bloodletting was
considered the remedy _par excellence_ for pneumonia and it seemed
justified by the marked relief to breathing and pulse which usually at
once followed a free bleeding. In a short time, however, the fever would
rise anew and the distressing symptoms reappear, which led the school of
Broussais to repeat the bleeding, _coup sur coup_, as often as the
exacerbation appeared. There was no respite for either age or condition,
the debilitated city toiler, the babe at the breast, and man of eighty
tottering into the grave had alike to submit to the lancet, and when the
oppressive symptoms returned, the blood had to flow anew. Broussais
himself, however, recognized his error in his later life, and remarkably
enough, his conversion was effected through veterinary practice. His two
carriage horses were successively attacked by pneumonia: the first was
treated by bleeding _coup sur coup_ and recovered: the second was put
under a more conservative treatment and also got well, but while the
first remained soft, flabby, debilitated and susceptible for a length of
time, the second was on convalescence at once able to go into active
work. The enormous abuse of bleeding, led to its more complete
abandonment than would otherwise have been probable, and the contrast
between the high mortality of cases treated by excessive bleeding, and
the lower fatality in pneumonias treated without phlebotomy on the
expectant (let alone) plan of Dietl or the stimulating method of Todd,
Bennett and others, served to hasten its abandonment. Yet in
bloodletting we have an instrument for good or evil which is not to be
judged on slight evidence. The mere lessening of the blood pressure is
to be little considered, as it requires the abstraction of nearly
one-third of the entire mass of blood to visibly affect this. The
vascular walls at once adapt themselves to the lessened amount. Nor is
the mere lessening of the volume a vital point. After moderate bleeding
this is made up in a few hours: after severe bleeding in 24 to 48 hours.
The loss of adult red globules is more lasting. Bleeding to the extent
of one per cent. of the body weight may have the number restored in
seven days. The young red globules though rapidly produced have
individually less hæmoglobin, and they can convey less oxygen to the
tissues. This should mean less oxidation, less heat, less waste, less
urea, uric acid, hippuric acid and other poisonous products in the
tissues. Yet Baur says that in anæmia there is a greater metabolism of
proteids and more excretion of urea. How easy it is to blunder in
looking from one single point of view. Again after bleeding there is a
great relative increase of the various forms of white blood globules,
most of them young and therefore with somewhat altered functions. The
paucity of red globules and excess of white are brought about by the
pneumonia and independently of bleeding, so that it is difficult to say
whether the phlebotomist is enhancing an evil, or helping a natural
therapeusis. It seems hopeless to estimate the effects of these and
other changes in the blood after bleeding, upon the metabolic processes
of nutrition, secretion and sanguification. This digression has not been
made to elucidate the results or the _modus operandi_ of bleeding, but
rather to illustrate the complexity of the problem involved and to warn
against broad and unwarranted generalizations from insufficient
premises.
Even today practitioners of the soundest judgment meet with a limited
number of cases in which they resort to bleeding with advantage. These
occur mainly in strong, robust constitutions, in individuals accustomed
to an invigorating, open air life, liberal diet and abundant exercise.
Even in these this measure is chiefly resorted to, to relieve an acute
pulmonary congestion with a dangerous distension and over charging of a
fatigued and overworked heart. In short the condition is one closely
allied to acute congestion in which the value of bleeding is all but
universally admitted. It is especially warranted early in the disease,
though it may still be adopted with caution in a similar condition which
has supervened at a later stage. A strong pulse and bright red mucous
membranes, are not as has been supposed, essential prerequisites to its
employment. The mucosæ may be pale, or more likely cyanotic, and the
pulse small and weak, from the over charging of the heart and its
tendency to failure, and it is to relieve these conditions that we adopt
this most potent of all measures for securing a temporary lessening of
the blood pressure in the right heart and pulmonary circulation. Even
the transient relief may allow this to right itself and then less
radical or dangerous measures may be relied on. Bleeding should very
rarely be resorted to save at the outset of the disease; extensive
exudation into the lung tissue strongly contra-indicates it; it cannot
be safely employed in the very young or old, in weak or debilitated
subjects, when the pneumonia has relapsed or supervened on another
serious malady, or when occurring in an unhealthy district. Delafond met
with a very high death-rate from bleeding in a damp undrained locality.
Where bleeding is permissible, the blood should be drawn from the
jugular in a full stream, from a large orifice, the finger being placed
upon the pulse, and the flow arrested as soon as the blood is felt to
pass along the vessel in a fuller, freer current, and the breathing is
seen to be relieved. It can rarely be repeated with profit or safety,
and in the vast majority of cases can be well dispensed with altogether.
_Antipyretic Treatment._ When the temperature runs dangerously high, a
temporary use of antipyrin, acetanilid, phenacetin, or other potent
antithermic remedy may be resorted to. But agents that so profoundly
affect the heat centres are not devoid of danger and should not as a
rule be continued after the dangerous excess of temperature has been
overcome. They may be looked on as valuable to temporarily obviate an
extreme danger rather than as a form of regular treatment.
The modern resort of applying ice bags to the chest may be similarly
disposed of. In very high fever they have been apparently beneficial,
but the danger of chill or injurious reaction is so great that they must
be employed with the greatest possible consideration and care.
_Refrigerant Febrifuge._ Neutral salts such as saltpeter in 2 drachm
doses every six hours may be given in the drinking water. These are
valuable for their cooling and eliminating action, and possibly in
counteracting the viscidity of the blood and exudations. Acetate of
potash, bicarbonate of soda, iodide of potassium or muriate of ammonia
may be substituted.
_Stimulants._ In debilitated subjects or with low fever or oppressed
heart the stimulating diuretics like sweet spirits of nitre or liquor of
the acetate of ammonia are to be preferred, and this is especially the
case during convalescence. They at once sustain the flagging heart and
aid in the excretion of morbid products. Digitalis is often of great
value in the same sense, and as a heart stimulant nux vomica.
Some follow Todd and Bennett in seeking stimulation from alcohol,
ammonia and its salts, ether, etc. When the circulation is weak or
flagging these are often of value and they may even act directly on the
pathogenic microbe. The inhalation of oxygen, or the solution of
peroxide of hydrogen given by the mouth has often an excellent effect.
_Sedatives._ Aconite has become too much of a domestic remedy,
nevertheless it may be used with advantage in high fever with excited
heart action, to moderate the circulation and relieve the breathing.
Veratrum, hydrobromic acid, bromide of sodium or ammonium, or chloral
hydrate may be used as alternates or substitutes.
_Compresses._ _Fomentations._ _Poultices._ No measure is safer nor more
promising, especially in the early stages, than the poultice jacket or
compress. A blanket wrung out of hot water is wrapped around the chest,
covered with a thick dry one, and held firmly attached by elastic
circingles. Or soaked cotton wool is applied and covered with a dry
blanket or a rubber sheet. The more acute the inflammation the more
valuable is this measure.
_Derivatives._ As a derivative the mustard pulp rubbed in and covered
with thick paper or rubber is especially valuable. In one hour it may
secure a free exudation and material relief to the breathing. It may be
replaced by ammonia and oil, with or without a covering, by hot water or
by cantharides. This must however be used with judgment. In the early
stage with a high type of inflammation and fever the surface irritation
may aggravate this through sympathy; in such cases therefore the
severity of the inflammation should first be moderated before using an
active counterirritant. In debilitated conditions, too with an altered
or depraved state of the blood and during the prevalence of a low type
of the disease, sloughing may ensue from incautious blistering.
The repetition of the blister is often useful, the healing process going
on simultaneously in the blistered surface and the diseased lung by
virtue of nervous sympathy.
To complete recovery a course of vegetable tonics, such as gentian, nux
vomica, calumba, may be given with iodide of potassium for a week or
more. Constipation occurring during convalescence must always be
corrected by food, (bran mashes, linseed gruel), injections, or
oleaginous, saline, or aloetic laxatives. The greatest care should be
exercised to secure pure air, comfort, sunshine, good grooming and
general hygiene, and to prevent over-exertion during convalescence.
In the _subacute_ types of pneumonia the fundamental difference in the
treatment consists in the avoidance of all depressing remedies and the
employment of stimulants and a supporting diet from the beginning. Sweet
spirits of nitre and liquor of the acetate of ammonia, carbonate of
ammonia or salammoniac with digitalis and strychnia may be used from the
first. Vegetable tonics may be resorted to at an early stage, peroxide
of hydrogen, and when expectoration is established and the fever
moderated even mineral tonics may be employed. Nourishing gruels,
mashes, roots, green food, and scalded oats may be used in turn to coax
the appetite and not to satiate. In other respects the treatment is the
same as for the acute. This form of the disease is liable to prove
obstinate and persistent, and there appears to be a greater tendency to
complications and so-called metastasis, as enteritis, laminitis or
rheumatoid affections of the back or limbs. These when they occur must
be treated as if they had arisen in ordinary circumstances, having
regard meanwhile to the remaining inflammation in the lungs, for that
has not necessarily been quite superseded but only alleviated.
CHRONIC PNEUMONIA. This has been described but if uncomplicated by
consumption it appears to be usually only that consolidation of lung,
due to the organization of exuded products into fibrous tissue, which
occasionally forms a sequel of acute inflammation of the lungs. In such
cases an access of circumscribed local congestion is liable to result
from over-exertion, or a chronic state of irritation is maintained
attended with more or less fever, inappetence, mal-assimilation, and
often in the long run hectic, under which the animal is worn out. In
such cases the chief indications are to avoid overwork or any undue
strain upon the breathing organs, to support the patient by nourishing
and easily digested food, and to control and remove any local irritation
by measures indicated under the head of acute pneumonia.