Chapter XVIII

, on Blood Pressure.)

CONTUSION OF THE BRAIN.

The condition of _shock (cerebral concussion)_, when of pure type, passes away with reasonable promptness, especially when aided by surgical treatment. _Anything which persists_ in the way of muscle paralysis, disturbance of function of nerves of special sense, or _other sign of importance_, indicates something more than mere vibratory disturbance: it implies mechanical lesion which could be perceived by the eye were the parts exposed, and constitutes the condition known as _contusion_. This implies the existence of trifling exudates, or hemorrhages, which lead not only to absorption but even cicatrization. _Contusion pure and simple_ differs from ordinary _laceration_ as a contusion elsewhere may differ from a wound. It cannot be separated, however, from conditions in which there are minute separations of continuity and actual lacerations. It may be divided into three postmortem forms--_general hyperemia_, with or without edema; _punctate_ or _miliary hemorrhages_; and _thrombosis of minute vessels_, which may occur separately or together. Moreover, there may exist similar lesions in the meninges, constituting _meningeal contusion_. Ordinarily minute vessels of the pia are ruptured and blood is effused in small and thin patches over various parts of the brain. The so-called _compression apoplexies_ of certain authors are inseparable from the conditions above described. Such minute blood clots are only to be distinguished upon very careful sectioning of the brain, and are found most often in the region of the medulla and along the floor of the fourth ventricle. They are probably caused by the forcing into the fourth from the lateral ventricles of the fluid contained in the latter.

=Symptoms.=--When the ordinary symptoms of shock, which follow all severe injuries to the head, especially when the deep lesions are not too severe, fail to disappear in a short time under proper treatment, and when new and irregular symptoms are superadded to those of shock alone, it is reasonable to suppose that the intracranial condition is one of contusion rather than of shock. When mental agitation changes into delirium, when the rapid, feeble pulse becomes stronger and slower, the respiration deeper, the limbs move in incoördinate ways, the speech disturbed from muscle incoördination, the patient selects wrong words, or when the mental condition becomes more serious and stupor or coma take place of the delirium, while external irritants have less and less effect, and when the pupils gradually enlarge while failing to respond to light, it may be said that the _condition of contusion is making itself apparent_. If along with muscle uncertainty there is also muscle spasm or rigidity, with fixation of the fingers in the athetoid position, the evidence to this effect is increasing. If with all this the thermometer fails to show that an active inflammatory condition--_i. e._, meningitis--is prevailing the diagnosis may be regarded as certain. Error may possibly arise when there are evidences of alcoholism. Coma following head injury ought not to be ascribed to the _alcoholic condition_ except by the strictest process of exclusion. Temperature alone will be of the greatest service in this direction, since in _alcoholism_ it is usually _subnormal_. In _apoplexy and non-traumatic hemorrhages_ it is also usually _subnormal at the commencement of the attack_, rising to normal, and remaining there if the patient recover, but _continuing to rise in cases where the prognosis is bad_.

=Treatment.=--The treatment of brain contusion should be managed largely in response to special symptoms. Physiological rest, attention to scalp wounds, fractures, etc., shaving of the scalp, application of ice to the head, with such stimulation to the heart as may be necessary in extreme cases by subcutaneous administration of adrenalin, atropine, etc., by local fomentations over the epigastrium, or by immersion in a hot bath when surroundings permit it--these in a general way constitute most of the methods of treatment in contusion. When only symptoms of diffuse and minute lacerations can be recognized the use of the trephine is impracticable except when indicated by some external marking--_i. e._, compound fracture or the like. When _localizing symptoms_ are present the trephine is, of course, indicated. When the skull injury is recognized as a basal fracture, venesection or the application of leeches behind the ears will be most serviceable. In every such case there is the greatest necessity for _regulating the excretions_ and preventing auto-intoxication. For this purpose diuretics and laxatives should be used, often in conjunction with intestinal antiseptics. The catheter should be employed whenever indicated by the condition of the bladder, which should be carefully watched. As the days go by, and patients lie more or less helpless and inert, the greatest care should be exercised for the prevention of bed-sores. When mental inertness, muscle rigidity, etc., fail to disappear, potassium iodide should be used internally.

BRAIN PRESSURE OR COMPRESSION.

That the cranial contents--brain, blood, lymph, and cerebrospinal fluid--completely fill the cranial cavity has been already amply shown, as well as that there is no room for anything in the shape of a foreign body without seriously affecting the equilibrium between the brain and the contents of the spinal canal. When, however, any foreign substance exerts pressure upon the brain the results are invariably the same, be this substance what it may, and _compression signs are always the same, no matter what the compressing cause_. Reduction in capacity of the cranial cavity (_i. e._, compression) may be produced--

[Illustration: PLATE XLIII

FIG. 1.

FIG. 2.

FIG. 1. Compound Fracture of Cranium, with Depression; Fracture of Bones of Face; Extradural Clot from Rupture of Middle Meningeal Artery.

FIG. 2. Horizontal Section of same, showing Depressed Fracture of Bone. (Anger.)

C, extradural clot; D, laceration of brain substance, with extensive intracerebral clot; F, same condition produced by contrecoup. Punctate hemorrhages and minute lacerations at numerous points, characteristic of contusion of the brain.]

1. By reducing the dimensions of its enclosing walls (_e. g._, depressed fractures or by direct pressure);

2. By increase in the quantity of cerebrospinal fluid or of the volume of the brain, which latter may be produced by edema, by serous exudate, or by actual hypertrophy;

3. By foreign bodies, which may enter the skull from without;

4. By pathological conditions--collections of blood or pus, tumors, etc., which may be produced either from the brain substance, its containing bone or membranes, or its vessels.

In every one of these conditions the size and tension of the brain are affected. _The cerebrospinal fluid is mainly involved in acute not in chronic conditions._ A slow reduction of the diameters of the skull produces such slow alterations of pressure as to cause a minimum of disturbance. So far as compression from traumatic influences is concerned we distinguish mainly between compression--

1. By extravasation of blood (see Plate XLIII);

2. By fractures of the skull with depression, or by foreign bodies penetrating from without;

3. By products of acute infectious inflammation due to septic infection from without.

The result common to all of these is _increase of intracranial tension_, and its consequence is a less rapid flow of blood and an altered blood supply to the brain and its membranes.

Experiment has established that in compression of the brain cerebrospinal fluid is forced by pressure into the spinal canal, whose membranes are more elastic, and which thus help to accommodate it; it has been also established that compression of the brain by one-sixth of its volume, by any material, is fatal, and that much less is at least serious. That fractures with depression produce sometimes serious, at other times trifling, symptoms is due to the varying accommodation of the spinal canal. Both experiment and observation seem to confirm the view that consciousness pertains to the cortex as a whole, and that unconsciousness is an inhibitory or paralytic condition which is produced in compression.

_Temperature_ is a matter of great importance in studying compression and foretelling its consequences. Elevation of temperature is an early, continuous, and constant symptom in these cases. If temperature be subnormal and subsequently rise, prognosis is bad. Variations of temperature are more reliable guides than conditions of consciousness. As Phelps has remarked, in no condition except sunstroke is temperature so uniformly high as in cases of serious encephalic lesions.

=Symptoms.=--As indicated above, the symptoms and signs of compression are practically identical, no matter what the compressing cause. When this cause acts instantly there is no time afforded for differentiation, but when it occurs slowly we note the following symptoms, and about in the order here presented: Irritability or restlessness; visceral disturbances; pain; intense cephalalgia; congestion of the face; narrow pupils; augmented pulse, often seen in the carotids. If compression occur more rapidly, torpor quickly succeeds erethism, after which patients vomit, have convulsions or at least convulsive motions, speech is disturbed, and stupor comes on, from which they neither awake nor can be awakened until the compression is relieved. All of these indications refer to involvement of the cortex, which is generally regarded as the seat of consciousness as well as of projection and imagination. During the night, of the senses produced by pressure upon the cortex only the automatic basal apparatus and that of the spinal cord continue in more or less disturbed operation. Of all the general functions consciousness vanishes first and returns among the last. When intracranial pressure has reached a certain point, epileptiform convulsions result, varying in intensity, affecting all the limbs, and terminating perhaps with rigidity. These form an expression of high pressure. Similar convulsions occur in various head wounds, explanation for which is the result of pressure, which, though not extensive, may produce alteration in the circulation, with its disastrous consequences. The later and _constant evidences of compression, and those which in aggravated cases supervene at once_, are reduction of pulse rate, due to the action of the pneumogastric, which suffers first an irritation and later a paralysis. The pulse becomes not only slackened but full; the respiration rate is correspondingly reduced, so that breathing during coma is deep, slow, and often stertorous. This feature of stertor is an expression of paralysis of the palatal and pharyngeal muscles, which flap, as it were, in the air current. Vomiting, which may occur before brain tension has risen high, does not occur in the most serious cases. Coma is absolute.

Along with these signs the most important other indications are the _paralyses_, which may consist of monoplegia, hemiplegia, or paralysis of individual muscle groups, according as pressure is made upon a limited area or upon an entire hemisphere. By the division of the cranial cavity by the falx and the tentorium it is divided into chambers, in any one of which pressure may be more manifest than in the others. Nevertheless a serious compressing cause will affect the tension of the cerebrospinal fluid and produce general expression of pressure. The _pupils_ often vary, and responsiveness to light is occasionally noted. Nystagmus and ocular rotation may be occasionally seen. Choking of the optic disk is also a frequent phenomenon, to be recognized only by ophthalmoscopic examination. This is due to pressure in the subdural and subarachnoid prolongations along the optic nerve. In milder cases of chronic compression disturbances of vision are of very great clinical importance. These pertain especially to diagnosis of hydrocephalus and of brain tumors. When they occur immediately after injury and remain, they depend upon laceration or other severe injury of the optic nerve. Those which quickly disappear depend mainly upon pressure of blood, which is reabsorbed, while those which are later in their appearance depend upon later intracranial complications. A unilateral lesion of the optic nerve depends most often upon injuries to it within the optic canal. When the lesion is bilateral the cause lies deep. General paralysis may be of the type of hemiplegia, single or double--_i. e._, by “double” I mean paralysis of the entire voluntary musculature of the body, which necessarily implies serious and often fatal hemorrhage.

=Prognosis.=--This depends in large degree upon the nature of the compressing cause and of the possibility of its removal. While the nature of the same may ordinarily be determined, how much can be accomplished by way of removal may often not be foretold before the operation at which this should be attempted. In every acute case it is desirable to make this attempt early, for high pressure, which may be borne for a short time, is fatal if continued. Compression to any serious degree is usually fatal. So soon as paralysis of circulatory and respiratory centres is apparent the beginning of the end is at hand. Another reason for hastening operation is that acute softening of brain tissue comes on promptly, as well as _general cerebral edema_, which has destroyed many a patient during the second to the fourth day after injury.

=Treatment.=--The treatment of compression is summed up in one phrase--_i. e._, to remove the cause when possible. The only cases in which this rule may be safely disregarded are those where the attempt to remove the cause means more danger than to leave it unremoved. This is not true, however, in the ordinary cases of bone depression, meningeal hemorrhage, etc. Before operation, however, or as a substitute for it in cases of minor severity, it may be well to assist venous outflow by _venesection_, by which blood pressure is reduced. In these cases this may be done from the temporal veins or external jugulars, with the patient in the semi-upright position. Drastic purgatives may also be employed in order to utilize intestinal outpour as a stimulation to resorption of cerebrospinal fluid. The physiological action of cold (ice-bags) may also be secured for the purpose of contracting the cerebral arteries. But all these measures are only to be resorted to when there is uncertainty as to the wisdom of operating, since when operation is indicated it should be done at once, and _should take precedence of everything else_. This operation means ordinarily the procedure to which the now general term _trephining_ has been, by common consent applied, and comprises any measure by which the skull is opened at a suitable place and the dura or the underlying cortex exposed to such extent as to permit removal of the compressing cause. Whether the opening be made with trephine (annular saw) or with the straight or revolving saw, with bone chisel, with bone forceps, or with anything else, is a matter of choice on the part of the operator. So, too, removal of the compressing cause should include the elevation of depressed bone, the removal of dislodged

## particles as well as of all foreign bodies, the cleaning out of blood

clot, the checking of hemorrhage, and the closure of the wound, with or without drainage or counteropening at some other part of the skull, as may seem desirable in special cases. This entire procedure comes now under the name of trephining, and should in most instances be painstakingly followed.

The operative maneuvers will be discussed in another portion of this chapter.

INJURIES OF INTRACRANIAL VESSELS AND SINUSES.

Intracranial hemorrhages may occur--

(_a_) From internal sources through the broken bone or between it and the dura (extradural);

(_b_) Beneath the dura, between or into the membranes (subdural);

(_c_) Into the brain substance proper or the ventricles (subcortical or intraventricular).

The vessels whose injuries are most often under consideration are the _meningeal arteries_, the _sinuses_, the _small vessels of the membranes_, and the _internal carotid_. The arteries, like the sinus walls, may be ruptured either by substances forced in from without or by sheer laceration. The _longitudinal sinus_ is most liable to injury from without. When this sinus is exposed, it may be dealt with either by suture if the wound be small, or by ligation, or by tamponing with prepared gauze. Hemorrhage from this source is ordinarily not difficult to check. Fatal air embolism has resulted through an opened sinus not properly plugged. The other sinuses are more rarely injured, as by gunshot wound, fracture of the base, etc. The sinuses have also been injured by compression of the skull during parturition. Bleeding from a sinus is usually indistinguishable from that from a meningeal artery, except that the former occurs more slowly.

=Injuries to the Middle Meningeal Artery.=--Injuries to the middle meningeal artery naturally occur in the immediate neighborhood of this vessel, which is not infrequently ruptured by contre-coup. The artery runs sometimes in a groove of the bone, sometimes in the dura, and sometimes entirely in the bone. The more it lies within the bone the more likely it is to be ruptured when this part of the skull is fissured. Basal fractures often follow the groove for this artery. The anterior branch is more often injured than the posterior. Extravasations from this source are more common than from all others combined, the amount of blood varying within wide limits. 240 Gm. of blood clot have been known to collect and the dura to be separated down to the base of the skull. I have repeatedly taken away a small teacupful of blood clot in such cases (Fig. 377 and Plate XLIII).

[Illustration: FIG. 377

Compression following hemorrhage from the middle meningeal artery. (Helferich.)]

=Symptoms.=--The symptoms of this hemorrhage are those of compression, while extravasation may be rapid and quickly fatal, delayed for some time, or may take place in two stages, the first but slight and producing no coma. New clots are always dark and disk-shaped, thick in the middle, with a definite margin. As the clots become older they become more adherent and difficult to remove. The symptoms of meningeal hemorrhage consist of an interval of consciousness or lucidity after injury, followed by epileptic or spastic symptoms, alterations in the pupils and pulse, unconsciousness passing into coma, and stertorous respiration. There may or may not be external evidence of head injury. The character of the _paralysis_ (hemiplegia) may indicate that the clot is really upon the side opposite to that of the skull which shows evidence of injury. In this case arterial laceration is the result of _contre-coup_. According to the rapidity of the symptoms is the extent of the primary lesion. Meningeal hemorrhages involve immediately the motor area, which makes diagnosis all the easier.

=Injuries to the Carotid.=--Injuries to the carotid within the cranium are exceedingly rare. Still, it has been injured in basal fractures and penetrating wounds.

=Arteriovenous Aneurysm.=--Development of arteriovenous aneurysms after basal injuries is occasionally noted. They will occasionally give rise to pulsating exophthalmos. Pulsating tumors within the orbit which push the eye forward not infrequently occur after serious head injury. Of 77 cases collected by Rivington, 41 had a traumatic origin.

=Subdural Hemorrhages.=--Subdural hemorrhages are not infrequent in the skulls of the newborn, and constitute the so-called _apoplexia neonatorum_. They may occasion convulsions and paralyses of irregular type, while if the extravasations become infected multiple abscess may result.

In adults subdural hemorrhages are most commonly connected with brain lesions which have been already spoken of as contusions. They may be the starting points for pachymeningitis. Their most common results are disturbances of consciousness and mentality. Paralytic dementia follows in some of these cases. Extensive subdural hemorrhage may give a clinical picture corresponding to extradural. Disseminated minute ecchymoses constitute minute focal lesions, which are, however, usually so distributed as to confuse and prevent accurate diagnosis. Apoplexy or intraventricular hemorrhages, especially from the lenticulostriate artery (Charcot’s “artery of hemorrhage”), have until very recently never been regarded as warranting surgical interference. Of late, however, especially in the ingravescent or progressive forms, ligature of the common carotid has been of some service, though in order to render this effective ligation should be done early.

=Traumatic Intraventricular Hemorrhage.=--Traumatic intraventricular hemorrhage occurs in much the same way as meningeal, by contre-coup. Individuality of symptoms is lost in the general comatose condition of the patient, but when operation is performed, as it is usually best to perform it, if no extradural clot be found and if brain tension be evidently increased, the dura should be opened; after which, if no subdural clot be seen, the ventricles should be tapped with an exploring instrument. In this case, if blood be removed by aspiration, a knife should be passed directly into the ventricle, after which blood, if present, will promptly escape. Dennis was the first to diagnosticate the presence of intraventricular clot and to deliberately incise into it, and I have myself repeatedly imitated this procedure, both with and without success.

In every case in which superficial or cortical hemorrhage can be recognized--or even suspected--or intraventricular hemorrhage as well, one should insist upon exploration. This means trephining, with perhaps aspiration of the ventricular contents. Tapping of the ventricle is described under Treatment for Hydrocephalus, while trephining is described at the end of this chapter.

LACERATIONS AND INJURIES TO THE BRAIN SUBSTANCE.

These have been mentioned under _contusion of the brain_. They may be divided into those which occur with or without fracture of the cranial bones. The term contusion was first suggested by Dupuytren. The condition comprises all degrees of injury, from the most minute local disturbances to lesions involving the entire hemisphere. The milder forms show a sprinkling of punctate hemorrhages, numerous in the centre of the injured area, the surrounding tissue taking on a more or less diffuse tint, which fades out toward the periphery, discoloration being due to the imbibition of the coloring matter of the blood. In more extensive injuries clots as large as peas, or larger, are embedded at various points, each surrounded by its area of discoloration. When foreign bodies have been driven into the brain the tissue is also discolored, while various foreign materials may be met. In instances of great violence there may occur absolute rupture of brain tissue extending from cortex to ventricle.

=Prognosis.=--Prognosis depends in large degree upon escape from or occurrence of infection. In infected cases the principal dangers are from blood pressure and from later edema or acute softening as well as from meningitis. Brain lacerations may heal by cicatricial repair, but usually with some perversion of function.

The possibility of _cystic degeneration of large or small clots_ is one of great importance. (See Cysts of New Formation in