Imagens das páginas





“Fever is for the physician what the sun is for the astronomer.”

Formerly this heat-producing central body of the planetary system was considered a dark mass surrounded by a layer of clouds and the latter enveloped by a light-productive atmosphere (photosphere); so fever was a clouded terra incognita, its crigin hidden or misplaced, and vague suppositions in the medical world tried to explain the glowing and burning of the body.

In ancient times the theory prevailed that fever was produced by the passage of blood from the veins into the air-conveying arteries, but with the discovery of the circulation, fever theories took a new departure, developing more and more—still at the present time (Prof. v. Recklinghausen says in his pathology) we almost fail to have a correct knowledge of this important process. Some of his most remarkable phenomena—the type, crisis, especially the cyclical succession of events can only be accepted as naked facts.

Before reviewing the principal modern theories, I will consider to what degree each organ is capable of producing warmth:

Muscles (muscular tissue and musculo-motor nerves) have the power of developing heat. Prof. Wunderlich observed in several cases of rheumatic tetanus a temperature of 1120 F, which after death increased to nearly 123° F. Billroth and Leyden noticed a rise of 9° F, in tetanic contractions produced by electrical irritation of the spinal cord. Hard work or muscular efforts of any kind create a considerable elevation of temperature and Hirn calculated in the human individual, the production of 150 units of heat during rest and 250 while working a tread-mill one hour.

Helmholtz, Bernard and others came to the same conclusion by


experimenting on frog's muscles. In the human biceps they found with the aid of a thermo-electrical apparatus, an increase of 3.5° F, after a single contraction. Breschet and Becquerel found the human biceps to be 4.6° F warmer than the surrounding cellular tissue. The action of the heart produces 103 units of heat in 24 hours, nearly as much as the whole body generates in one hour. (Grehaut).

2. Based on experiments, Bernard and Ludwig also attributed to glands the power of warmth production; the former found the maximum height of temperature in the liver.

3. Nerves can produce warmth independently. Prof. Wunderlich observed agonistic elevations of temperature in neuroses, hysteria, etc.; even normal individuals are subject to rise of temperature under the influence of mental excitement and the more sensitive their nervous system, the more frequent will be the change of temperature.

Next I will review some of the modern fever theories.

Weber, Billroth and Hueter regard the blood as the homestead of fever, and febrile metabolism as a simple chemical act caused by the introduction of decaying and decayable substances, parasitic organisms which appear in the blood, conveyed through the general circulation to destroy tissue elements.

The majority of observers regard the nervous system as first involved by the pyrogenetic material, producing the abnormal conditions of texture and warmth economy.

Virchow maintains that the nervous system is a general regulator, which can be disturbed under pathological conditions (moderating centre).

H. C. Wood, Namyn, Quinke, etc., accepted this theory, some locating the centre in the brain, others supposing an additional centre in the spinal cord.

Stilling argued the existence of a thermal centre in the medulla oblongata, which may, either directly or indirectly through the peripheral nerves be irritated or blunted, reacting not only on the musculo-motor but also through the sympathetic on the vaso-motor nerves, thereby increasing or diminishing the activity of the heart and the rapidity of the circulation. The chill indicating the depression and heat the stimulation of thermal nerves.

Bernard attempted to prove, that the sympathetic system was an inhibitor of warmth production by cutting the same on one side of neck. He demonstrated an elevation of temperature and flushing of side of head corresponding to the nerve cut, and that the abnormal production of heat depended upon paralysis of the sympathetic nerves. Chill being instigated by general irritation and heat by general relaxation of the vaso-motor nerves.

Schiff disproved the above by the experimental production of fever under similar conditions; he found no elevation but rather a diminution of temperature on the operated side as compared with the normal and concluded that the febrile condition of the circulation was due not to vaso-motor paralysis but as in inflammatory congestion, to increased activity of the vaso-dilators, the frigid state being produced by excitation of vaso-constrictor nerves.

Bernard later adopted Schiff's theory and differs from him in only one particular. Schift maintains that the physiological and pathological production of warmth is caused by the influence of the nerves on the circulating apparatus, while Bernard attributes to the vaso-dilators and vaso-constrictors, which he calls thermal nerves, an additional action on the chemism of the tissues independent of their vaso-motor influence.

Traube and Marey believe, that fever begins with tetanic contraction of the arterioles, due to irritation of the vaso-motor nerves.

Leyden supports the latter but supposes a paralysis of the vasodilators of the integument, consequently insufficient perspiration and radiation of heat in proportion to the increased production and accumulation while the vessels remain contracted.

Goltz and Kendall discovered perspiratory nerve fibres possessing independent power and concluded that suppression of perspiration bears no definite relation to the febrile course.

We owe to Zuntz interesting communications about the influence of toxic remedies on tissue metamorphosis. Strychnia innervates and curare enervates or suspends tissue metamorphosis. Zuntz experimented on slightly curarized animals (rabbits) without disturbing their normal temperature or circulation and found after infecting them with blood of septic animals, which ordinarily produced fever, no increased consumption of O. nor increased expulsion of CO,

If this negative result should prove constant, if one can produce febrile metamorphosis easier in strychnized animals than in normal, if these poisons do not suspend the pyrogenetic power of infectious matter as is claimed of quinine, then it only goes to prove that the

muscles are the principal seat of febrile metabolism and next to them their nervous system (Recklinghausen.)

Quite independent of what we call tever, though one of its symptoms, is rise of temperature. Quinine lowers temperature 2°F; 3°F in fever but in non febrile states it has no power to reduce even very high temperature, the latter being controlled by sedatives.

In this century, which may be called the century of germs, it seems alınost proven that all micro-organisms, known as injurious to health, can produce different degrees of what we call fever depending upon the number or the locality from whence they spread (blood, glands, muscles, etc.)

I will now consider the question of elevation of temperature.

Elevated temperature, a febrile symptom which may exist independent of fever, I regard as originating from the nerves and as caused by a disturbed circulation of the blood, due to the presence of virulent microscopical organisms, depending as before said, upon their number and locality.

Children have a more sensitive nervous system than adults and during dentition the pressure of the tooth on the gums or its nerves will produce elevation of temperature. Even convulsions are frequently observed in teething children, the central nervous system being easily influenced by peripheral irritations.

Often before the symptoms of an infectious disease are ushered in, we observe convulsions in children or rigors in adults. Every alteration in circulation has a tendency to develope an elevated temperature, as is frequently observed in pregnant women.

In the beginning of tubercular phthisis, physicians advice patients to take deep inspirations, thereby improving the circulation of the apices of the lungs and to prevent the stagnation and proliferation of the bacilli.

After the bacilli have invaded the tissues and found sufficient time to proliferate and form a colony, they begin to spread, and with their progressive activity varies the abnormal temperature. That is why in slow lingering tuberculosis elevated temperature is for a long time of very subordinate character, while in acute cases the elevated temperature is a cardinal symptom.

It is considered impossible for a human being to exist with a temperature of 107°F-108°F, an elevation above latter is called

hyperpyrexia or agonistic temperature. If this maximum is reached death occurs as in insolation.

In nervous diseases a high temperature can be borne with less constitutional disturbance, because the warmth-producing nerves alone are involved, and the injurious and virulent action of infectious germs is lacking.

The same manifestations which we observe in fever—dilation and constriction of the vaso-motors—can be noticed daily in cutis anserinus, which can be provoked voluntarily in nervous persons.

Brown-Sequard proved a temporary rise of temperature and paralysis of the affected side after partial division of the spinal cord. The same has been observed in cerebral apoplexy. Similar are the observations in sunstrokes.

If there is a specific fever-bacillus (which I consider doubtful), it resides in the blood, as is evident in malaria, for the blood of the latter transferred to healthy individuals will produce the same dis


As the tide alternately rises and falls in the ocean so the temperature of the blood in the normal body differs morning and evening and this periodicity is not suspended in fevers.

Prof. Hueter says in his first volume of lectures on surgery, that wound-fever depends chiefly upon local inflammations. He gives credit to the possibility that some phlogistic fevers are mediated through the nerves, others through the circulation.

Quoting him, most of the inflammations are produced by the influence of micro-organisms (schistomycetes) on living tissue.

These germs, which may be called wound-fever-germs, exist in the air and are brought in contact with poorly dressed wounds.

Pasteur, Nussbaum, Hueter, etc., claim it to be utterly impossible for wound secretions to undergo putrefaction without the presence of microscopical germs in the wound blood, lymph or nutritive fluids.

Bergman, Pasteur and Cohen succeeded in preparing nutritive fluids for the growth and development of these germs.

Thermal and chemical agents may produce inflammation but if kept aseptic, no formation of matter.

Bruises may be accompanied by febrile symptoms, which means perturbation of circulation or contusion of vaso-motor nervous system.

« AnteriorContinuar »