[By Lucy Waite, A. B., M. D., Head Surgeon of Mary Thompson Hospital for Women and Children.]

    Shock in its widest significance covers the whole of medicine.  From the slightest physical traumatism or the lightest mental depression to the most profound impressions on the vasomotor centers causing instantaneous death, the difference is only one of degree, the phenomena being the same.  It would therefore be impossible in one short chapter to follow out the subjects in all its various ramifications in the field of medicine and surgery and it must suffice to treat it in a comprehensive manner as an affection primarily of the nervous system with the secondary involvement of the vascular system as a whole.

HISTORY.

    While it is only during the last fifty years that any scientific experiment,.; have been made with a view toward discovering the pathology of shock, as early as 1826, Travers, in his work on Constitutional Irritation, gave an exact description of the phenomena of shock.  The first treatise on the subject I have been able to find was published in 1868, by Edwin Morris, F. R. C. S. In this he states that the first mention of shock in medical literature was in 1819, in the works of F. Hennen and Guthrie, writing on military surgery.  Morris considered death from shock due to functional disturbance of the brain, the heart being affected only secondarily.  He places no emphasis on the part played by the sympathetic system and mentions this only once incidentally as the par vagum and says it connects the spinal cord, brain and heart. lie treats of shock under two headings, surgical and shock from mental causes.  He gives the classical symptoms and concludes that shock is due to paralysis of the nervous system destroying the normal function of the brain and withdrawing the nervous stimulus from the heart.  He confuses shock and concussion of the brain, but warns against confusing this condition with extravasation in injuries to the brain.
    I have given a brief synopsis of his brochure because, being written in a comprehensive manner and as late as 1868, we may assume that it contains all that was known on the subject up to that date.  Previous to this mention was made of the subject in Cooper's "Medical Dictionary" in 1838 and in Copeland's "Dictionary" in 1858.  In Cooper's "Surgical Dictionary," published in 1859, however, there is no mention of shock.
    One of the most interesting landmarks in the history of the literature on shock is Davey's work published in 1858.  Under the heading of "Syncope" he gives a long dissertation on the phenomena of shock, although this word is used only once, and he foreshadows both the present theory of the pathology and the latest treatment as demonstrated by the experiments of Dr. Geo. C. Crile and others in his observations on collapse after labor and the too rapid escape of the ascitic fluid in paracentesis abdominis.  "I am, however, confident," he says, "that the bona fide explanation of the fact is to be sought for in loss of the long-accustomed adaptation or relationship between the containing and contained parts of the abdomen, whereby the ganglionic nervous system is at its very center more or less paralyzed."
    He says he has no doubt that the many cases of sudden death attributed to cerebral hemorrhage, disease of the heart, air embolism, etc., are in reality caused by "syncope," as he terms it, and that the cause is to be found in the fact that "the ganglionic nervous system has been drawn on so largely by the cerebro-spinal and muscular systems that there is nothing remaining for the thoracic and abdominal viscera-no stimulus left for the vital organs." Mr. Paget, writing in 1862, gives the phenomena and treatment.  Later Brown-Sequard and Savory (1870) made the valuable discovery of the pathology of shock.  Brown-Sequard announced as the result of his work the theory of anaemia of the cerebral centers due to a more or less persistent contraction of the capillaries through the vasomotor center.  The experiments of Goltz on frogs was the most important work done in this direction until the last few years.  With Brown-Sequard and Savory, he held to the theory of cardiac paralysis.  He showed that through the inhibitory influence exerted upon the splanchnics, the abdominal vessels were suddenly dilated.  In Quain's "Medical Dictionary" (1884) is a statement of the status of the subject of shock at that date and concludes: "For the present we may thus accept as the most plausible interpretation of the symptoms of shock a sudden dilatation of the abdominal vessels, attributable to an inhibitory influence exerted upon the splanchnics, through the medium of a special reflex center." Not much has been added to this explanation of the real pathology of shock, but valuable experiments have been made in recent years in the line of pathology, and some working toward a more rational treatment by Geo.  C. Crile, Robert Dawbarn, Harvey Cushing, Eugene Boise, Guy C. Kennam'an, John H. Packard and others of our own profession.  In the extensive surgical encyclopedia edited by Dupley and Reclus in 1890, "Traite de Chirurgie, " is the statement that it is only during the last twenty years that shock has been studied in France and that the French, in acknowledging the origin of the researches in this subject, often use the English orthography, although having a legitimate word in their own language, "choc." A differential diagnosis is made between shock and syncope and the article concludes by saying that in fact we know nothing of the pathological anatomy of shock or of its pathogenesis.  The entire bibliography on shock is so meager that it may be interesting from an historical stand point.  In addition to those already maintained, the field is practically covered by the following:
    Gross, "System of Survey" (1864).
    Erichsen, "The Railway and Other Injuries to the Nervous System" (1866).
    Verneuil, "de la mort prompte apres certaines blessures ou operations" (1869).
    Savory, "Collapse," "Holmes System of Surgery" (1870).
    Fisher, "In Volkman Samml, klin.  Vortr.  " (1870).
    Demarquay, "In comptes rendus de l'Academie des sciences" (1871).
    Renard, "Arch; Gen. de med.  " (1872).
    Blum, "Du choc traumatique Arch. gen de med, " (1876).
    Le Dentu, "Bull de la Soc. de chir." (1877).
    Vincent, "Des causes de la mort prompte apres les grands trauma tismes accidentels et chirurgicaux Thesis" (1878).
    Piechaud, "Que doit on entendre par 1'expression de choc traumatique" (1880)
    Jondan Furneaux, on "Shock after Surgical Operations and Injuries," "British Medical Journal" (1880).
    Raffer, "La Spermantate" (1882).
    Torrier, "choc traumatique Elements de path. chir. generate" (I885).
    George Friedlander, "arch. fur klin. chirurg.  " (1903-4).
    Dennis, "System of Surgery" (1895).
    Mummery, Second Hunterian lecture, "New York Medical Journal" of April 15, 1905.

AETIOLOGY.

    From clinical observation of the phenomena of shock, a rather arbitrary division of the aetiology has been made, viz.: Predisposing and exciting causes.  To establish this as a scientific classification much more must be known regarding susceptibility to shock.  Infants are said to be almost immune, while youth is considered the period of the highest susceptibility.  Immunity is therefore before the age when the cerebrospinal and sympathetic systems assume their reciprocal positions in the nervous system, susceptibility from the time when the untrained cerebrospinal system assumes more established control over the sympathetic until the element of mental influence comes in as a factor.  To counterbalance this extreme susceptibility of youth comes in the fact that at this time the resisting powers are greater and many cases are recorded by different authors of recovering from the most profound shock in the young which must certainly have proved fatal in the old.  It would almost seem that the proposition could be laid down that the power to withstand and overcome shock is in inverse ratio to the susceptibility.  Dr. Kiernan says that the insane are not susceptible to the influences which produce shock in the sane, and in fact the effects may be directly contrary - a wide field for study and speculation.  Certain peoples are said to be practically immune and others to be little affected.  Dr. John H. Packard writes interestingly on this subject.  He says that Hindoos bear injuries and operations impassively; that Negroes are not easily affected and that Americans are especially susceptible to the influences of shock.  It has been observed that injuries inflicted while the subject is under the influence of intoxicating liquors rarely produce severe shock.  If all these clinical observations can be substantiated it would point very strongly to a large mental element in every case of shock, either directly or indirectly.  When all is said, however, the real factor in each constitution which speaks for or against susceptibility, the vital force, will after all no doubt remain the unknown quantity.  As regards the varying degrees of susceptibility in the different organs of the body, the most vascular tissues and those most highly supplied by the sympathetic nerve have been found to be most easily affected.
    In the present light of our knowledge we may consider as predisposing causes all conditions which impair the nutrition of the nervous system and consequently the circulation; exhausting diseases, prolonged physical pain or mental strain, insomnia, melancholia, in fact, everything which reduces vital force.  Mummery says in his second Hunterian lecture that in elderly patients a very high blood pressure is generally observed, largely accounted for by arteriosclerosis, and that in such patients a relatively slight fall in blood pressure may produce shock.  It is as a predisposing cause that hemorrhage plays its proper role through the secondary physiological phenomena of anaemia which leaves the ganglia to be bathed with impoverished blood and as a surgical condition to be handled surgically should be sharply differentiated from shock proper.  The exciting causes of shock may be more satisfactorily considered under the classification of traumatic and mental.  Direct traumatism of the tissues may result from accidental injuries or from trauma during the course of surgical procedures.  Many writers treat this last condition under a separate classification as surgical shock.  It seems true that this subject can be treated scientifically only as a subdivision of the general classification of traumatism, which is either accidental or surgical.  The confusion has arisen by considering hemorrhage as an exciting cause of shock instead of giving it its proper classification as a surgical complication and secondly by the involvement of the anaesthesia in the aetiology.  All surgical writers agree that the frequency of shock has greatly lessened since the general use of anaesthesia and this fact speaks loudly against operating under partial or local anesthesia, as a routine practice.  I have seen patients profoundly influenced by an excessive quantity of the anesthetic, either on account of the manner in which it was administered or the length of time the patient has been held under its influence, with no symptoms of shock whatever, and I cannot think the effects of long anaesthesia, serious as they are, can legitimately be considered as factors in the production of shock.  The whole story of a depressed nervous system following a prolonged anaesthesia is told in the added traumatism caused by the repeated and unnecessary handling of the tissues and the exposure to atmospheric influences tissues normally protected by the coverings of fascia and skin.  During extensive experimentations in intestinal operations on dogs, Dr. Byron Robinson demonstrated that the shock following these procedures was in direct proportion to the amount of manipulation or traction in the abdominal viscera and duration of exposure; that is, the amount of trauma inflicted upon the sympathetic nerve.  Sudden blows, especially in the region of the solar plexus, burns and scalds involving large areas, all manner of traumatic injuries, especially those producing extensive crushing of tissues, are the principal exciting causes in shock from accidental traumatism.  It has been observed that burns involving a large area, causing extensive nerve periphery trauma, cause more profound symptoms - than deeper burns covering a small area.  Irritation in one organ may produce nerve storms in a distant one.  The introduction of the sound in the uterus or the catheter in the male urethra may produce faintness, nausea or even vomiting.  Dr. Nicholas Senn demonstrated a rare case in his clinic which well illustrates the principle of reflex nervous irritation.  The patient came into the hospital with a history of anurea for sixty hours.  The right kidney was enormously distended, the left apparently normal.  A diagnosis was made of right ureteral calculus, which was removed.  During the period of convalescence both kidneys secreted an equal amount of urine, proving conclusively that the suppression of urine from the left kidney was caused by the reflex irritation produced by the disturbance in the right.  The size and extent of the renal ganglia and their nearness to the solar plexus give to the kidneys an especially strong sympathetic connection.  From the first observations made in the subject to the present day, all writers have recognized the mental element in Etiology of the phenomena of shock.  Davey, 1858, cites in detail many cases and says the part played by the mind in the production of "syncope" is not sufficiently appreciated.  Clinical observation has established the fact that a profound mental impression may cause all the nervous phenomena following a blow over the solar plexus.  Sad news, fright, violent emotions may be followed by the same vasomotor paralysis with all its accompanying nervous manifestations; and when this is said, all has been. said regarding our knowledge of the influence of the mind in the production of the phenomena of the shock.

PATHOLOGY.

    As the result of some experimentation and much speculation two theories regarding the pathology of shock have been evolved, viz.: Vasomotor paresis and cardiac paralysis.  Almost all of the modern investigators hold to the theory of vasomotor paresis.  The nervous impression is conveyed to the medulla by the afferent nerves, causing vasomotor paralysis and dilatation.  There is a more or less rapid fall in blood pressure.  The vessels lose their normal tonicity which is necessary to the rapid transition of the blood, the first effect is contraction in the caliber of the capillaries, followed quickly by dilatation, with at first increase in rapidity of the blood current, but in proportion as the dilatation increases the rapidity decreases and may proceed to a complete stasis.  The right side of the heart becomes engorged and does not empty at each contraction, accumulating largely in the relaxed veins, leaving the arteries partially emptied; the patient bleeds into his own veins.  The blood is normal into the abdominal vessels.  Cerebral anaemia results as a natural consequence and a slowing of the activity of all the different viscera dependent for the fulfillment of their physiological functions upon a perfect blood supply.  The influence on the heart together with all other viscera is therefore secondary to the paralysis of the vasomotor system through the great reorganizing center, the solar plexus, the abdominal brain.  The phenomena of shock are therefore the result of a reflex inhibition affecting all the functions of the nervous system, causing a lowering of the general blood pressure, checking normal metabolism, arresting the exchanges between blood and tissues; the venous blood becomes red, temperature lowers in consequence of the lowered blood pressure, respiration slows and we have a picture of systematic asphyxia.  The entire mechanism of life is deranged, the balance of power is destroyed and each organ is in an independent control of its own functions for the time being and consequently only as long and as thoroughly as its limited reserve force will allow.  Brown-Sequard, Goltz and Savory advanced the theory of cardiac paralysis. They gave as the conclusion of all their experiments that shock was caused by a violent impression on some portion of the nervous system acting at once through a nerve center upon the heart and destroying its action.  No reliable findings have been found at autopsy.  Parascandola claims to have found certain changes in the spinal cord after profound shock affecting the cell body, prolongations nucleus and nucleolus, constituting chromatolysis, fragmentation, nuclear and perinuclear.
    It must be admitted that the pathology of shock after all remains very indefinite and unsatisfactory, the x, as Dr. Senn has called it in the surgical formula.  It is therefore very difficult to give a comprehensive definition of this ignis fatuus in the domain of pathology.  Based in reality more on the phenomena than upon the pathology, according to our present light we must consider it as primarily a disturbance of the great sympathetic nervous system afflicting secondarily the entire vascular system, a more or less profound impression on the sympathetic nerve producing a vasomotor paresis with a consequent dilatation of the right side of the heart and the large vessels, especially the abdominal, and in consequence lowering the general blood pressure and deranging through the solar plexus all the automatic visceral ganglia, and consequently destroying their functional activity. rhythm, absorption and secretion.

SYMPTOMS.

    The phenomena of shock manifest themselves through the tripod of vital forces, the nervous, circulatory and respiratory systems, and principally in those organs most highly supplied by the sympathetic system.  The rhythm of the viscera is disturbed, secretions are diminished, causing an intense thirst, the cry of the tissues for fluids; there is a general trophic disturbance; the heart action and the respirations are increased, the temperature is subnormal, the face is pale, the lips are blue, the pupils dilated; there is nausea, vomiting and restlessness, more or less pronounced according to the degree of shock, until the stage of collapse, when the reflexes are lost.  A cold, clammy sweat appears on the entire surface of the body, and the extremities are cold.  Shallow respirations, with frequent sighing, yawning, hiccoughs are often added to the clinical picture.
    In the most profound shock, where the cerebrospinal system is involved, this picture may be changed by the substitution for the phenomena caused by a hyperirritation of the sympathetic system as nausea, vomiting and restlessness, those manifestations resulting from a secondary depression of the cerebrospinal system causing a loss of reflexes, as involuntary urination and bowel movements; delirium and even stupor may appear.  The cold sweat, rapid, irregular pulse, subnormal temperature here persist in a more profound degree, some observers having noted a fall in temperature of 6^o F. During the War of the Commune observations were taken in regard to the temperature after injuries.  The average temperature varied from 96.5^o to 97.5^o, the lowest registering at 93.5^o. The fall was greater after shell wounds and the curious fact was noted that there was a uniform lower temperature among the insurgents than among the regular troops.
    Authenticated cases have been reported where jaundice, deafness and arrest of lacteal and menstrual secretions have followed profound shock.  Many efforts have been made to classify the nervous symptoms of shock, but all are unsatisfactory for the reason that one state runs so insensibly into another that it is impossible to measure the degree, except by the rate of recovery, and here again come in the unsolved problems of susceptibility and resistance and we simply travel in a circle and soon find ourselves at the starting place again.  The only classification which is any aid in diagnosis and prognosis is a differentiation between the state implicating only the functional activity of the sympathetic system and that in which the cerebrospinal is also involved and even here the symptoms run so imperceptibly into each other that classification is elusive; even in collapse consciousness may be retained until death.
    The intensity of physical shock is influenced by four principal considerations: the extent of the injury, that is, the number of nerve peripheries involved; the nearness of the traumatism to the solar plexus; the character of the injury, the more crushing or bruising of the nerves the greater being the nervous impression; and the severity of the pain produced.  It is therefore from the standpoint of intensity rather than by means of a scientific classification that we must study the phenomena of shock.

DIAGNOSIS.

    The diagnosis of shock is simply the recognition of the clinical phenomena as here we have no pathological findings to aid us.  The clinical manifestations of this nerve storm are however so pronounced that practically the only difficulty lies in differentiating this condition from syncope caused by severe hemorrhage, with which there is danger of confounding it. When syncope co-exists with shock it is often extremely difficult to establish the presence of internal hemorrhage as a complication.  In one condition the blood leaves the peripheries and congests the abdominal vessels, in the other the large and small vessels are equally deprived of the usual volume of blood.  In nervous shock certain tissues only lose their blood supply, while there is no diminution in the quantity of blood.  In the one the primary violence is to the nervous system, in the other the circulatory system is attacked directly.  Syncope causing always a cerebral anaemia is practically identical with the last manifestations of overwhelming shock, or collapse.  As a recognition of the presence of hemorrhage is often of the utmost importance, sometimes meaning even the saving of a life, we should never rest content with a diagnosis of shock until we have excluded the possibility of hemorrhage by every means in our power.  If the patient is seen immediately after the injury, or in surgical cases where internal hemorrhage may arise, the most reliable source for establishing a differential diagnosis is by observation of the pulse and temperature.  Both conditions, to be sure, produce a rapid pulse with normal or subnormal temperature, but there is a decided difference in the course of the pulse and temperature which with careful observation one can not fail to recognize.  In internal hemorrhage there is a gradually rising pulse, more or less rapid according to the rapidity of the bleeding, with a gradual lowering of temperature, the golden rule in abdominal surgery establishing the presence of internal hemorrhage laid down by Mr. Lawson Tait over twenty years ago.  In shock proper, however, we have the maximum rapidity of pulse and depression of temperature at the time of infliction of the trauma and co-existent with all other clinical manifestations, as the rapid shallow breathing, cold sweat, and dilated pupils.
    To illustrate: A patient is taken from the operating table with a ten,perature of 99^o-100^o, rectal, pulse 90-100.  In a half hour the pulse is 110-120, the temperature is found to be 98^o; in another fifteen minutes to half an hour the pulse has risen to 180-140 and the temperature is falling towards 97^o and the diagnosis of internal hemorrhage is practically established.  This rising of the pulse with a corresponding depression of temperature may be extremely gradual and extend over hours and even days in cases of slow bleeding, sometimes a mere oozing, as where an hematoma or an hematocele is forming and before the period of infection or localized peritonitis, and here of course the diagnosis is more obscure, but fortunately less urgent.  If, however, the patient is taken from the table with a pulse of 120-140 or upwards, rectal temperatures 98⁰-97⁰, respirations 80-40, and even if these conditions persist for several hours, we have no reason to fear internal hemorrhage, and if after the first half hour of the patient's rest in bed the pulse and respiration slow ever so little and the temperature rise even a fraction of a degree we may know that we have to deal with a case of recovering shock.  The surgical nurse should be taught to make this differential diagnosis through a clinical study of pulse and temperature and respiration, as it is to her that we must look for the accurate observation and a prompt report of a condition in which minutes count in the saving of a life.

PROGNOSIS.

    We have little to guide us in forming a prognosis, as here again the . unknown quantity, the vital force of the individual, the power of resistance of the tissues to the nervous impression comes in as the most important, factor in the equation.  In general the temperature. is the best guide here also.  A persistence of 96^o or below for several hours warrants an unfavorable prognosis while even a slight rise from time to time may be taken as a happy omen.

TREATMENT.

    The many and diverse theories regarding the treatment of shock shows conclusively the chaotic state of the professional mind regarding this condition.  One writer is so confused in his interpretation of the phenomena that he advised at the same time morphine, strychnia, digitalis, nitroglycerine, whisky and citrate of caffeine.  No one has done more to bring order out of this chaos than Dr. Geo.  C. Crile, of Cleveland, by his experiments on dogs.  He has practically demonstrated not only the uselessness but the harmfulness of strychnia in shock and that the rational treatment lies in raising the blood pressure. He lays down the principle that the treatment must be sedative to the sympathetic system and relaxing to the arterioles.  To this end he advises compression of the abdomen and extremities to prevent the accumulation of blood in the large veins, with the administration of adrenalin given with salt solution.  Dr. Halsted advises morphine also normal salt.  It is interesting to note that Morris, as early as 186S, advised opium 1- 2 gr. every two hours.  Rest and heat, preferably moist, added to these remedial agents, and we have certainly fulfilled the requirements for treatment in accordance with all that is known of the pathology of shock, to quiet the nervous system and relax the arterioles.  The addition of strychnine, digitalis, nitroglycerine and whisky is certainly irrational.  The heart is already overworked by nature's effort to repair the damage and strychnine may prove to be what the whip is to the spirited horse at the end of the race, and under its influence the heart may exhaust itself in a last effort.  When there has been hemorrhage as a complication the first indication is most assuredly to restore the volume of blood, but it is certainly irrational to increase the quantity of blood suddenly when the normal amount is present in the vascular system and the difficulty lies in reality in properly caring for the usual quantity.  It would seem theoretically that increasing the volume of blood rapidly under these conditions would only increase the local congestion in the large blood vessels and make the ultimate restoration of the normal blood pressure more difficult.  Small quantities of hot water per mouth or rectum sufficient to allay the thirst, or the slow, continuous rectal irrigation, which introduces the fluid gradually and as the tissues are prepared to appropriate it seems to me to be more rational than intravenous infusion of a large quantity of fluid.  Briefly stated, the treatment in hemorrhage is to restore immediately the normal volume of blood, in shock to restore the normal blood pressure.  Dr. Robert Dawbarn calls attention to the danger of using plain water in intravenous infusion in hemorrhage and says that experiments on dogs have proven that it will kill almost as quickly as prussic acid.  He advises normal salt solution at a temperature of 118o-120o F., one to two quarts, ten minutes to be taken in introducing it.  If the kidneys are not functionating normally, the quantity must be lessened.
    Some writers make a point on the value of force of gravity and advise lowering of the head.  Mummery says that the ideal treatment of shock would be the raising of the external air pressure, and thus substituting an artificial peripheral resistance for the lost peripheral resistance caused by the exhaustion of the vasomotor centers, but that as yet this method is not practical.
    The administration of foods and drugs by the stomach is distinctly counterindicated.  The same principle holds good here as in the case of the heart.  The stomach is exhausted and oversensitive and should not be irritated or stimulated to work until the period of exhaustion has passed.  Perhaps the principal factor in the therapeutics of shock is rest, anatomic and physiologic rest.  This of course forbids all stimulants, alcoholic as well as stimulating drugs.  Light and sound should be excluded that the tired brain may share in the general calm with which we seek to surround our patient.

PREVENTION.

    The preventive treatment of shock lies almost entirely in the domain of surgery.  Here is indeed the ounce of prevention worth a pound of cure.  Paget in 1868 advised hypodermics of morphine after operations before the patient is restored to consciousness to lessen the shock caused by pain.  Davey in 1858 recommended waiting in cases of shock injuries not complicated with hemorrhage until some of the "Promethian fire" had returned to the shocked tissues.  Dr. Harvey Cushing and Dr. Crile advise the cocainization of main nerve trunks thus "blocking" the nerves proximal to the site of operation, in severe cases where shock may be anticipated.  Dr. Crile has invented a pneumatic rubber suit with which he envelops the patient, which he claims assists greatly in preserving the normal blood pressure.  There is no doubt that much can be done by the proper preparation of the patient before coming to the operating table to prevent subsequent shock and the practice of some surgeons of rushing nonemergency cases under the knife without any preparatory treatment cannot be too strongly condemned.  It is self-evident that the more normal the condition of the system the greater will be the resistance of shock.  The indication, then, is to bring all organs as far as possible to their highest function.  This is especially important in the case of the kidneys, bowels and skin, the great eliminatory organs; these must actually secrete normally at the time of operation if we are to expect normal conditions to follow.  Free drainage by means of nature's own remedy, water used liberally, internally and externally, for several days previous to operation, will in ordinary cases be sufficient to put the kidneys and skin in good condition.  A free catharsis, making sure that the entire intestinal tract is cleared, is of the utmost importance.  The liberal use of a normal salt solution as long before the operation as possible not only aids in the systemic drainage but increases the volume of the blood and promotes the rapid metabolism which is so important in preserving the quality of the flood.  The stomach should be absolutely empty when the patient is brought to the operating table, as it is one of the first viscera to manifest reflex irritation, and a persistent nausea and vomiting keeps the patient in constant distress and the muscular system in action, preventing the rest and relaxation so necessary to recovery.
    Rapid operating, as rapid as is consistent with a proper attention to detail, is unquestionably one of the greatest factors in the prevention of surgical shock.  The entire regime of the operating room should be conducive to this end.  Every detail, should be attended to as far as possible before the patient is placed under the anaesthetic.  Minutes wasted for any reason while the patient is under abnormal conditions is an injustice to all concerned.  In abdominal surgery involving the peritoneal cavity there is little doubt that shock is in almost direct proportion to the amount of handling and exposure of the intestines.  Mummery says that turning the intestines out of the abdomen is always followed by a sudden and dangerous fall of blood pressure.  Methods of operating, therefore, in which these viscera are little or not at ail exposed can certainly claim to be a factor in the preventive treatment of shock.  I have frequently seen patients put to bed after the removal of large myomata (hysterectomy) per vaginam with no more symptoms of shock than after a normal labor.  The choice of anaesthetic in cases where shock is apprehended is considered by sorpe of great importance.      Mummery says that ether anaesthesia almost always causes a rise in blood pressure, while chloroform is usually accompanied by a fall in blood pressure, and believes the chloroform-ether mixture to be the best anesthetic from the point of view of subsequent shock.  It would seem, however, that there are more important points to be considered in the choice of an anaesthetic, as the organic condition of the heart, kidneys and lungs, as we have more definite knowledge of the action of ether and chloroform on these organs.  The temperature of the operating room is of great importance, and should be kept between 80^o and 85^o F.  Wetting and chilling of the body should be avoided, and heat applied directly by means of a water cushion placed over the operating table assists greatly in preserving the normal body temperature.  The mental state in which the patient comes to the operating table is no doubt an important factor.  Every effort should be made, therefore, to inspire the patient with confidence in the success of the operation, that the demon of fear may be exercised from the sick room, that the spirit of hope may hover around the last few conscious breaths and be the first to greet the awakening mind struggling back to consciousness.