Hyperemia as a therapeutic agent was described by Bier and is of two kinds, active and passive. The former is the same as the arterial, while the latter is the venous. Between the blood of active and passive hyperemia there are important physical and chemical differences, the one containing much free oxygen with but little carbonic acid and alkali, while the other presents the exactly opposite character.

In active hyperemia normal elements of the blood are kept in active motion, while in the passive form they are allowed to escape, more or less, into the tissues.

Hyperemia possesses a great many properties:

Hyperemia may be produced in three ways; first, by means of the elastic bandage or band; second, by cupping glasses, and third, by hot air. The first two produce venous or passive hyperemia, and the third, arterial or active hyperemia.

Passive Hyperemia. This obstructive hyperemia is produced by means of a thin, soft rubber elastic bandage, two or three inches in width, better known as the Esmarch, or Martin bandage. When this is applied moderately tight around a limb about six or eight turns, one layer overlapping the other, pressure is evenly distributed over a comparatively wide area, causing the subcutaneous veins below the constriction to swell; the extremity becomes somewhat bluish red in color, also larger and edematous, giving a feeling of warmth to the touch.

The rubber bandage, properly applied, should not cause any uncomfortable feeling and there should be absolutely no pain present. At all times one must be able to feel the pulse below the site of the bandage. If the bandage is applied too tight, the skin of the limb looks grayish-blue and there appear whitish, or vermilion colored spots, which grow larger and larger, as long as the too tightly drawn bandage is on. Paresthesia and pain, with disappearance of the pulse, can also be noted.

The two cardinal rules to be observed in the application of the bandage are: (1) absolutely no pain with the application of the bandage; (2) the pulse at all times must be felt below the bandage.

In cases which require the bandage to remain in place from sixteen to twenty hours each day, it will be necessary to first apply a soft flannel bandage underneath the rubber one in order to prevent pressure necrosis.

Frequently changing the location of the bandage up and down the extremity, and treating the skin with alcohol rubs, will also be helpful to patients with a tender skin. The elastic bandage must always be placed upon a healthy area, proximal to the diseased part. All dressings should be removed while the compressing bandage is on, in order that the part may become hyperemic.

Wounds or sinuses are covered with sterile gauze and kept in place with a towel, fastened with a few safety pins.

In acute inflammation, septic wounds and phlegmons, the increased inflammation is apt to frighten the beginner, but this is a desired phase of the treatment.

As a prophylatic against infection, it cleanses the wound, produces a local immunization and reaction before the infection has a chance to work; the earlier the bandage is applied the more remarkable is the effect.

For incised wounds of the foot with division of the muscles and tendons, if the tissues are not too seriously injured, the muscles and tendons should be united and the skin closed with interrupted sutures sufficiently far apart to allow free excretion. No drainage is employed and a slight compressing dressing is applied. The elastic bandage is applied very lightly, producing only a slight venous engorgement and the bandage should remain on from ten to eighteen hours a day.

As soon us the symptoms of acute inflammation subside, the time of application of the bandage is reduced. If signs of suppuration are present, the wound should be promptly opened and the pus evacuated. The knife takes care of the pus; hyperemic treatment fights the infection.

In gonorrhoeal arthritis of acute or chronic nature, and in cases of tuberculosis of the bones and joints, the passive form of hyperemia is especially indicated.

The use of cupping glasses is limited to abscesses, furuncles and sinuses.

Active Hyperemia, or arterial hyperemia, is produced by means of hot-air boxes such as the Tyrnauer electric apparatus, or the gas apparatus of Betz.

Active hyperemia increases the arterial blood to any part of the body, thus favoring the absorption of chronic exudates, infiltrates, adhesions, etc. Dry, hot air permits the use of a high degree of temperature without injury or pain to the respective part.

For neuritis of the foot, ulcers, especially diabetic, perforating and varicose, and for the stiffness following a chronic inflammation, or after a fracture, the arterial form of hyperemia gives good results.

COLD

Cold, or the rapid abstraction of heat, is a remedial measure that is nearly always available and is possessed of very great power for good in selected cases.

When cold is applied for its limited and local action, it is always used with two objects in view, namely, (1) to cause localized contraction of the blood vessels, which through inflammation are engorged, so that the parts are swollen and reddened; or (2) temporarily to anesthetize or benumb the nerve terminals, for the immediate relief of pain, in the hope that the temporary paralysis may ultimately result in such changes as to produce a cure.

Cold, in some form, is a popular remedy for a sprain, or any injury likely to be followed by inflammatory processes. A very useful remedy for the sprain of an ankle, when it is a recent accident, is to let the patient sit with the foot elevated, with a cloth wrung out in ice water, and an ice bag applied over the affected part.

In the treatment of localized pain or inflammation, cold is used in a number of ways, largely depending upon the will of the physician and the means of the patient. The simplest, cheapest, and perhaps the best method of using cold, is to place cracked ice in a rubber bag, the latter to be thoroughly watertight, lay it over the inflamed part, surrounding it with a towel so as to prevent the moisture, which appears on the surface from condensation, from wetting the clothing.

HEAT

Heat is used locally for a number of purposes in the same manner as cold, and the choice of heat or cold in the treatment of any acute form of inflammation depends almost entirely upon the wish of the patient, who generally can tell at once which will give him the greater comfort.

In sprains of the ankle, nothing compares to a hot foot-bath prolonged for hours, the object being to decrease the pain and swelling, thereby regaining the use of the limb.

The high degree of heat which can be borne by gradually increasing the temperature of the water by the addition of small quantities of scalding water, is extraordinary, and the favorable results obtained are in direct ratio to the height of the temperature.

Between these soakings, the part should be dressed with lead and opium wash, and rubbed with ichthyol ointment or camphor liniment.

Hot-water bottles or bags are also used locally for the relief of congestion and pain.

THE HIGH FREQUENCY CURRENT, OR VIOLET RAY

The Violet Ray or High Frequency Current is one which is in a rapid state of to-and-fro vibration and is applied through vacuum glass attachments or electrodes, which are excited to a beautiful violet color. The discharge may appear to the eye to be a single spark, but it is made up of a number of successive sparks, following each other with such extreme rapidity that they are said to oscillate (change directions) millions of times per second, a speed that the eye cannot note. The rapid oscillations have the effect of producing the following phenomena:

The contractile effect is expended upon the individual cells making up the tissues, instead of on individual muscles.

If a sedative effect is desired, keep the electrode in contact with the part; if a stimulating effect is desired, hold the electrode away from the surface; the farther away, the longer the spark.

A uniform spark of any length can be produced by administering the current through layers of toweling, or through the clothing; the length of the spark depends upon the thickness of the layers.

The use of the high frequency current in surgery is limited to sprains, stiff joints, neuritic pains, and adhesions due to inflammatory exudates. Fulguration for the destruction of growths is obtained by employing a pointed metal electrode.

RUBEFACIENTS

Rubefacients. These are agents which revulse by causing congestion of the skin:

1. Turpentine. A few teaspoonfuls of oil of turpentine sprinkled over a piece of flannel wrung out of hot water, applied to the skin and covered with oiled silk or dry flannel, constitutes the turpentine stupe. Twenty minutes is the maximum for this application.

2. Mustard. Mustard flour (the black being the stronger), mixed with tepid water into a paste, spread thinly on a piece of muslin or paper, and covered with gauze or thin cambric, is an excellent counterirritant. Few skins will bear pure black mustard for more than ten minutes. Mustard, diluted one-half with wheat or corn flour, and allowed to stand for twenty minutes, should be the maximum strength for application, because blistering must be avoided, that produced by mustard being specially painful. After removing a mustard plaster, greased lint should be applied.

3. Mustard Foot-Bath. A mustard foot-bath consists of one or two tablespoonfuls of pure mustard in a bucket two-thirds full of water at 105°F; the feet may be kept in this for about twenty minutes, a blanket being thrown around the limbs, and including the bucket, to retain the heat.

Revulsives must be used with caution in cases of shock or coma, lest impaired vitality or sensation to pain result in extensive sloughing of the skin.

CAUTERIES

The Actual Cautery is used in the form of variously shaped irons, hatchet-edged, round, or olivary, fitted into wooden handles, and heated in a charcoal furnace.

As a counterirritant, the iron should be heated only to a dull red heat, and should be quickly drawn in parallel lines, about one inch apart, over the skin, avoiding all bony prominences. Compresses wet with cold water, or with some antiseptic lotion, may then be applied.

The Paquellin Thermo-Cautery is a convenient form. It consists of hollow platinum cauteries and a handle covered with wood; a benzole reservoir; a pair of rubber bulbs, like those for a hand-spray apparatus, connected by a tube with the reservoir; a long rubber tube to connect the cautery handle also with the reservoir; and a spirit-lamp with attached blow-pipe.

Screwing on the desired point, the tube from the reservoir is slipped over the handle; the point is heated in the lamp; is removed from the flame; and, compressing the bulbs, which should previously have been connected with the reservoir, benzole vapor is forced into the point, which will heat up, and can be maintained at any temperature by the rapidity with which the bulb is worked. If the point will not heat with the simple flame, attach the bulbs to the blow-pipe on the lamp, and, compressing them, heat the cautery to a bright-red heat, and then connect with the reservoir and proceed as before directed.

Galvano-Cautery. This requires a battery of a few large elements closely coupled, and various curets, knives, and ecraseurs fitting into insulated handles. The chief advantage of this form of cautery is the possibility of placing the instrument in position while cold, and then heating it.

Where hemorrhage is undesirable, a dull-red heat should be maintained, for at a white heat the tissues are divided as if with a knife, and bleeding follows. When the ecraseur is used, needles must be passed at right angles through the healthy tissues, the platinum wire placed behind these, and the wire, at a dull-red heat, slowly tightened.

ELECTRICITY

Electricity. This is used in the form of the induced current (Faradism) to exercise and improve the nutrition of muscles, and in the form of the constant current (galvanism) along the course of nerve-trunks, to excite their conducting power, or to act as a sedative in neuralgias.

The same current is used to induce chemical decomposition (electrolysis) or to cauterize and destroy tissue by heating an encircling wire or by a galvanic knife. Franklinic, or static electricity, is also occasionally used.

Electrolysis. For electrolysis a galvanic battery of thirty or more medium-sized cells is required, with needle electrodes insulated, except near their points.

To destroy a verruca, introduce into it two needles, a short distance apart, each connected with a pole of the battery; then, commencing with a weak current, this must be cautiously increased, the sitting lasting from a half hour to one hour, after which the needles are to be removed and the punctures sealed by collodion.

MASSAGE

Massage. This is employed to stimulate the circulation in the part mechanically; to loosen tissues bound down by adhesions; to diffuse inflammatory exudates over a wider area, thus favoring their absorption; and to change the rate of the circulation to a point compatible with rapid absorption and normal nutrition.

Four distinct varieties of manipulation are found to be most generally useful:

Stroking consists in gentle rubbing directed from the periphery upward, commencing the process above the inflamed part and continuing it over the diseased area; the pressure, at first light but finally firmer, will force the exudates into the tissues above, which have been emptied by the preparatory rubbing.

Kneading means rubbing the part circularly with the pulps of the fingers and the thumb or the palm of the hand, and is best combined with pinching up of the skin or muscles singly or together, and gently rolling them between the fingers and palms.

Percussion is effected by tapping the surface over the diseased part with the tips of all the fingers held on a level, or with the ulnar side of the hands, or, after covering the part with a towel, three parallel pieces of stiff rubber tubing, fixed in a handle (a muscle beater), may be employed, gently striking the part transversely to its long axis.

Passive movements should be made at the close of each sitting if a joint is concerned.

Massage is sometimes advisable twice daily, but often once a day or every other day is better; each sitting may last from fifteen minutes to one hour.

EXAMINATION BY RADIOGRAPHY

X-Ray Examination. This method of examination depends on the property of penetration of matter possessed by a radiation from an electrically excited Crookes’ tube. This radiation has been proved to lie outside the spectrum, and has been named X-ray.

It may, for purposes other than those required by the expert, be looked upon as a source of light which has the property of penetrating the tissues to a greater or less extent according to their density, and the shadows cast by it can be recorded on a photographic plate, or may be viewed with the naked eye by means of a screen composed of a thin layer of barium platinocyanide, a substance which becomes highly fluorescent in the presence of this radiation.

One or the other of these methods is used for the recognition of pathologic conditions existing in the human tissues.

The fluorescent screen appears at first sight to be an easy way of recognizing abnormalities. Its value in the examination of the thorax, where the movements of the heart, lungs, and diaphragm have to be observed, is undoubtedly very great; but as an accurate means of recognizing any abnormality, it is untrustworthy. For instance, it is possible to fail to recognize simple transverse fracture of the tibia by its means. Its use is therefore to be deprecated in cases where great accuracy is necessary, and it is safer and better to make use of the more certain method, the photographic plate.

A further objection to the use of the screen is that the constant exposure of the hands and other parts of the body of the observer may result in an intractable, dangerous and chronic dermatitis.

By using a photographic plate the danger of dermatitis can be avoided, since it is not necessary to expose the hands at all; and at the same time greater accuracy is ensured and a permanent record is obtained.

Although examination by radiography is a somewhat tedious procedure in comparison with direct observation by the fluorescent screen, yet it is less difficult if the photographic side of this method is approached in a proper and businesslike manner.

Interpretation of Radiograms. A successful result in X-ray examination involves a clear understanding of the meaning of the radiogram produced. Even with the most accurate knowledge of anatomy, it is difficult to interpret X-ray shadows; for a radiogram is only a shadow, and the outline of the part thus demonstrated is liable to great variation. For example, in the case of injury to bone, it is always possible to secure strong and accurate X-ray shadows of the part, and no error ought to be made in diagnosis, yet errors of this kind are not uncommon.

To avoid such mistakes, it is imperative that the quality of the radiogram secured should be the best possible. For instance, in the examination of the ankle-joint and the bones of the foot, a radiogram which is flat, indistinct, and altogether wanting in detail, is of no value, while a radiogram of good quality of the same ankle-joint and foot, is of value. The interpretation of the latter is easy, while that of the former would be almost impossible, and certainly inaccurate.

The usual practice in securing radiograms is to place the subject in a position considered likely to give the best results, and then roughly, almost at random, to place the tube in some unknown relation to the part of the body under examination. The resulting shadow is often of no value because it is wanting in detail and depth. One method of avoiding this fault is to produce stereoscopic views of the part examined.

Two views having been secured in stereoscopic register, and placed in a stereoscope, the part can be viewed in relief. Theoretically, then, by this means one is able to view the parts of the body opaque to the X-rays as they would appear to the naked eye. In practice, however, this method, though it may prove of value in exceptional circumstances, is laborious. Moreover, though the parts may be made to appear in relief, they are not really as one would see them with the naked eye, but are still X-ray shadows.

A more practical method is to ensure that in all cases radiograms of any part of the body be absolutely comparable with one another by taking care to maintain the same relationship between the X-ray tube and the part under examination. For example, in making an examination of the ankle-joint, the limb is placed in a prescribed position, and the anode of the X-ray tube, that is, the actual source of the X-ray, is brought into accurate relationship to the tip of the internal malleolus by a simple mechanical contrivance, the details of which need not be dealt with here. This relationship between the tube and the ankle can always be reproduced, and therefore the shadow of a normal ankle-joint can always be obtained under the same conditions for comparison with the radiogram of the suspected ankle.

In this way, not only is the surgeon able to select the view of the part which will have the depth and detail necessary for proper interpretation, but, the shadow being familiar, he can more easily recognize any abnormality.

A radiogram secured under the conditions usually adopted, shows definite and known anatomic relationship between the bones and the X-ray tube, namely, with the anode of the tube directly opposite the tip of the internal malleolus.

To render this method of examination more perfect, there has been devised a system of radiography containing a definition of the relationships between the tube and the various parts of the body which have been found to give the most useful views, and also radiograms of the normal appearances of each part at the ages respectively of 5, 15, and 25 years.

By using this system the surgeon can secure a radiogram of any part of the body, of the requisite standard in quality, while he has at hand a normal radiogram of that part for comparison with the abnormal.

Having secured a radiogram of good quality, it is necessary for the purpose of interpretation that it should be viewed in a suitable light. The best for the purpose is a bright light shaded with opal in a dark room. The negative may be viewed at its best while still wet. Considerable loss of detail follows the taking of prints, which for this reason may greatly detract from the value of the radiogram.

It is a mistake to suppose that X-ray examination in the diagnosis of diseases can replace the older and well-tried clinical methods of investigation; it is merely a useful means of acquiring knowledge which, in conjunction with accurate clinical investigation, leads to a more accurate diagnosis and prognosis, and is often most useful by suggesting a more suitable line of treatment. It must be remembered that this method of investigation has been in use only a comparatively short time. In some diseases no definite statement is yet possible that may not prove in the future to be misleading.

At present the therapeutic use of the X-ray is rightly falling into the hands of the dermatologist and the medical clinician. In surgery, outside of the conditions mentioned above, its use is limited to lupus, keloid, epithelioma, sarcoma and carcinoma, both before and after operation.