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Introduction
Historically, the vast majority of penetrating head injuries (PHI) resulted from military combat operations; however, during the latter part of the twentieth century, these injuries have increased in incidence in civilian trauma centers. The difference in military and civilian PHI is often the nature of the penetrating projectile. In a combat situation, a majority of penetrating missile wounds are from either explosive munitions producing low-velocity fragmentation injuries or high-velocity bullets fired from vari- ous ranges.1 Civilian gunshot wounds primarily result from low-velocity bullets fired at close range, typically from handguns.2This accounts for a significant proportion of civilian injuries in the form of homicides, suicides, and accidents, with an estimated 2.4 deaths per 100 000 each year in the United States.3,4 With the recent increased threat of terrorist attacks, the penetrating and blast injuries traditionally seen during military conflicts may become more frequently seen in some civilian centers. As a conse- quence of the large number of patients with PHI treated during wartime, a number of the advances and refinements in the care of these patients have emerged from the military experience.
Prior to 1900, PHIs generally were considered fatal. MacCleod reported a 100% mortality in 86 cases of penetrating or perforating head injury during the Crimean War. During the American Civil War, the death rate from pyremia of wounds to the head was as high as 95% in some series.
Few surgical interventions were performed because of the high rate of infectious complications. The introduction of Lister’s antiseptic technique in 1867, more sophisticated understanding of cerebral localization during the late 1800s, advances in surgical technique during World War I (WWI), and antibiotics during World War II (WWII) gradually led to new optimism regarding the care of these patients.5,6
Major Harvey Cushing encouraged the systematic evaluation and treat- ment of patients with PHI during WWI. He emphasized the importance of early meticulous debridement of all devitalized tissue and removal of all
visualized fragments of bone and/or metal.The application of his techniques reduced the operative mortality from 56% to 28% within 3 months at Base Camp 5.5–9
World War II brought with it the broad application of antibiotics and the importance of dural repair. Operative mortality was reduced to 14.5%
during this conflict.10,11
During the Korean War, an improved medical evacuation system and the eventual placement of neurosurgeons in combat zones resulted in more immediate surgical interventions. This early intervention proved especially efficacious in the treatment of intracranial hematomas and resulted in fewer infectious complications. Surgical mortality was reduced to as low as 10%
in some series during this conflict.12
As a result of anecdotal reports describing delayed abscess development in PHI from WWII and Korea, the practice of aggressively removing all bone and metallic fragments in an attempt to reduce postoperative infec- tion was mandated in the U.S. Army during Vietnam. This approach some- times subjected a patient to multiple operations and occasional increased operative morbidity for what was felt to be an “adequate” debridement.13 Critical review of the results of patients at five and 14 years in the Vietnam Head Injury Study (VHIS) ultimately showed no difference in rates of infection or seizures in those patients with retained bone or metallic frag- ments as seen on computed tomography (CT).
This data was applied during the Israeli–Lebanese conflict where Branvold and colleagues14described a debridement strategy in 113 patients based on preservation of viable tissue with limited debridement. Fragments were removed with gentle irrigation and fragments that were not easily obtainable were left. Of the 43 patients with long-term follow up, there was a 51% incidence of retained fragments and no relationship to the develop- ment of intracranial abscess formation. Additionally, there was not an increased incidence of posttraumatic epilepsy with retained bone frag- ments.14These important experiences were instrumental in the evolution of the modern surgical management of PHI.
Ballistics
To understand penetrating trauma, it is important to have a basic under- standing of ballistics. Wound ballistics is the study of the projectile’s action in human tissue. The ballistic properties of a projectile are dependent pri- marily on its velocity, size, and shape. The primary injury to the brain is related directly to these properties. Secondary projectiles such as skull frag- ments may cause further damage.
Penetrating head injury can result from both low- and high-velocity pro- jectiles. Lower-velocity sharp projectiles such as arrows (120 to 250 feet per second) create a tract of primary tissue damage without significant bruis-
that is its key determinant.15,16The shape of the projectile determines the ballistic coefficient, which is its ability to overcome air resistance and main- tain velocity. The shape also influences the yaw, which is the projectile’s rotation around its long axis. While small amounts of circular motion (pre- cession and nutation) occur during flight, projectiles often will tumble when striking tissue.Yaw is maximized when the projectile is rotated at 90 degrees to its long axis.15,16This imparts more kinetic energy to the tissue, increases the size of the temporary cavity, and increases tissue destruction.
For example, a .45 automatic pistol (muzzle velocity of 869 feet per second and a short round-nosed projectile with little yaw) will create a very small temporary cavity; conversely, a 7.62 millimeter North Atlantic Treaty Organization (NATO) rifle (muzzle velocity 2830 feet per second and a long sharp nose with maximum yaw) will create a very large temporary cavity.
Projectiles also can deform or fragment upon striking tissue. Copper jack- eting lead bullets, as mandated for military rounds by The Hague Peace Conference (1899), helps limit the fragmentation potential. Irregularities made by scoring the surface of the bullet (dum dums) lead to increased fragmentation, creating multiple injury tracts as each fragment becomes a new projectile. The Glaser round is filled with small pellets that disperse on impact. Hollow-point rounds, often seen in civilian shootings, expand their diameter in the direction of flight upon impact, thus creating a larger primary wound tract and more destructive temporary cavitation effects.
Explosive bullets such as the Devastator round are designed to detonate on impact and thus will produce extensive tissue injury with additional kinetic energy transfer.17
Injury Classification
Since WWI, PHIs have been classified in an attempt to correlate the type of injury with prognosis. Cushing’s original classification of nine different injury patterns was refined by Matson in WWII to four categories, which are explained in Table 15-1.
Currently, a PHI is described as a tangential wound, a penetrating wound, or a perforating wound.
Tangential Wound
A tangential wound (Figure 15-1) occurs when a projectile strikes the head at an oblique angle and may produce scalp lacerations, skull fractures, and cerebral contusions. The projectile may traverse the subgaleal space and exit or remain lodged in the scalp. The presence of a hematoma, depressed skull fracture, or cerebrospinal fluid (CSF) leak may necessitate surgical intervention. Otherwise, local wound care may be applied. These injuries generally carry a better prognosis with less severe neurological deficits, but they may present with seizures or focal deficit depending on location and extent of injury.
Table 15-1. Cushing and Matson’s classification of craniocerebral injuries
Grade Cushing (WW I) Grade Matson (WW II)
Description Description
I Scalp lacerations, skull intact I Scalp wound
II Skull fractures, dura intact II Skull fracture, dura intact III Depressed skull fracture and III Skull fracture with dural/brain
dural laceration penetration
A: Gutter-type (grazing)—in-driven bone with no missile fragments B: Penetrating—missile fragments in
brain
C: Perforating—through and through IV In-driven bone fragments IV Complicating factors:
V Penetrating wound with A: Ventricular penetration projectile lodged B: Fractures of orbit or sinus
VI Wounds penetrating C: Injury of dural sinus
ventricles with: D: Intracerebral hematoma
A: Bone fragments B: Projectile VII Wounds involving :
A: Orbitonasal region B: Auropetrosal region VIII Perforating Wounds IX Bursting Skull Fracture,
extensive cerebral contusion
Figure 15-1. (A) CT of tangential wound to right occipital region from AK47 while wearing military helmet. Wound was emergently debrided at nearby field hospital.
Note the in-driven bone fragments. (B) MRI of same patient revealing underlying contusion after CT confirmation of no residual metal fragments.
䉴
B
Penetrating Wound
The velocity of the projectile is the main determinant of its energy. If the projectile has enough energy to only penetrate the brain parenchyma, the injury is referred to as penetrating. Energy absorbed by the skull often results in fragments of bone that act as secondary projectiles within the brain. Contusions, lacerations, or hematomas may be caused by these injuries (Figure 15-2).
Depending on the amount of energy, the projectile may produce unusual tracts within the calvaria that may be detected on CT, but missed on plain films. The projectile may ricochet after hitting the inner table opposite of its entry, creating a new tract within the parenchyma. It also may change directions when it hits dura after penetrating the outer and inner tables of the skull. This unusual occurrence is called careening. The projectile then travels along the inner table of the skull, with the potential to damage the venous sinuses.
Perforating Wound
The most destructive pattern of injury is the perforating wound (Figure 15-3), which is defined by an entry and exit wound with a tract through brain parenchyma. This injury requires a higher-velocity projectile than with a penetrating injury, and thus imparts a higher amount of kinetic energy to the tissue. Local and distant structures are damaged from the cavitation effect the projectile imparts, resulting in multiple fractures, contusions, and hematomas.
Initial Resuscitation and Management
In civilian trauma, activation of the local emergency medical service (EMS) system allows initial resuscitation efforts to be made in the field to include intravenous (IV) access and intubation when warranted. The use of a heli- copter allows for faster transport from the scene or outlying hospital to a neurosurgical center for early intervention.18,19
A combat situation provides a different operating environment for PHIs.
Initial care is provided by a medic carrying limited supplies and diagnostic equipment. In contrast to civilian systems, combat injuries are triaged in the field and at every level of care. Due to limited capabilities, the goal of combat medicine is to do the greatest good for the most people, thus main- taining the fighting force. If a patient is triaged as expectant, they are not prioritized for rapid evacuation, allowing those resources to be shifted to other, salvageable patients. Military neurosurgeons are viewed as assets, deployed where most beneficial.20Depending on the theater of operations, neurosurgical support may be located at a variety of locations or echelons.
Figure 15-2. (A) Gun shot entrance wound in left cheek (B) Gun shot exit wounds right periorbital region. Note the increased size of the exit wound compared to the entrance wound. (C) CT demonstrating intracranial involvement.
A B
C
A military neurosurgeon may be located in an austere field hospital. Alter- natively, he or she may be in a more sophisticated environment further along the evacuation chain. In urban conflict this may be an urban hospi- tal. Head injuries will need to be triaged and initially managed by medics, general surgeons, or general medical officers at more forward locations.
Medical evacuation for these patients, either by ground or air, can be delayed as a result of equipment challenges, the terrain, the weather, or the tactical situation. Proactive training and neurosurgical exposure to far- forward providers and utilization of telemedicine for neurosurgical consul- tation can greatly facilitate the care of these patients.
In either a civilian or combat environment, patients with a PHI often experience a period of apnea and hypotension. Early intubation and appro- priate fluid resuscitation may reduce the secondary complications from these events.18,19A challenge to early intubation in the field can be cervical immobilization. Kennedy and colleagues21reviewed the incidence of spine injury in patients with isolated gunshot wounds (GSWs) to the head. They found no spine injuries in 105 patients, suggesting that immobilization may not be necessary, facilitating intubation (see also Chapters 7 and 16).
As in any trauma, Advanced Trauma Life Support/Battlefield Advanced Trauma Life Support (ATLS/BATLS) guidelines are followed, with a focus on preventing hypoxia and hypotension. Both of these events significantly worsen the outcome of patients with head injury. Once IV access is obtained, laboratory evaluation to include electrolytes, complete blood count (CBC), prothrombin time/partial thromboplastin time (PT/PTT), type and screen/cross, urinalysis, and toxicology panel should be sent. A brief history from medics, family members, or paramedics is taken to include the mechanism of injury, neurological examination at the scene, periods of hypoxia or hypotension, and known past medical history or aller- gies. During the primary and secondary survey, the patient is inspected thor- oughly for entry and exit wounds, which should also include the oral cavity.
A temporary clean, bulky dressing is applied to the wounds.
Figure 15-3. CT of a perforating GSW with a transventricular tract.
Neuroimaging
Plain radiographic studies of the skull can provide a quick impression of the nature of the injury and evaluate for the presence of intracranial fragments and air, especially in circumstances where a CT scan is unavailable. The true trajectory of the fragment may be misleading in the presence of ricochet or careening fragments (Figures 15-4 and 15-5).23If rapid access to a CT scanner is possible, plain films are not required. Noncontrast CT with bone windows allow for precise localization of bone and projectile fragments, identification of the trajectory, and characterization of brain injury (Figure 15-5). The presence of mass effect and classification of hematomas, either epidural, subdural, parechymal, or intraventricular, can be performed.23
Angiography is recommended when there is a high suspicion for vascu- lar injury. From Aarabi’s experience in the Iran–Iraq war, there was a 4 to 10 time increased risk of traumatic aneurysm development in patients with facio-orbito or pterional entry, intracranial hematoma, or projectile
Figure 15-4. CT of GSW from close range demonstrating ricochet of fragment posteriorly off contralateral skull. Plain film correlation alone with right fronto- temporal entrance wound would lead to an incorrect assumption of true wound tract.
Figure 15-5. Lat (A) and AP (B) skull X-rays of GSW provides some information on retained fragments, presumed tract of injury, and involved structures. (C) CT scan gives a much better anatomic delineation of the injury.
A
B
trajectories that cross dural compartments.24Haddad and colleagues docu- mented 15 cases of traumatic aneurysms from the Lebanese conflict: 14 from fragmentation injuries and one from a bullet. From their experience, they recommended an angiogram for patients with retained fragments, no associated exit wound, and an intracranial hematoma in the distal portion of the trajectory.25 Other high-risk injuries include a projectile trajectory through or near the Sylvian fissure, supraclinoid carotid artery, basilar cis- terns, or major venous sinuses. After stabilization, any PHI patient who develops a new or unexplained subarachnoid hemorrhage or delayed hematoma should also undergo angiography (Figure 15-6).23,26
Magnetic resonance imaging (MRI) currently is not recommended in the acute management of PHI.23 Retained ferromagnetic fragments produce artifact, distortion, and also can rotate from the magnetic torque.27–29Mag- netic resonance imaging may be beneficial in certain cases where the pro- jectile is not retained or is known to contain no metallic elements (see chapter 23).
Preoperative Treatment
Increased intracranial pressure (ICP) is common after PHI.30–33The exact pathophysiology behind this elevation is not completely understood. The available data suggests that maintenance of an ICP less than 20 mm Hg has a more favorable prognosis than those with uncontrolled intracranial hypertension.34Increased intracranial pressure monitoring should be initi- ated when the clinician is unable to assess a patient’s neurological exam, commonly at a GCS score of less than or equal to 8. There are various means to monitor ICP, the most common being intraventricular catheters and intraparenchymal monitors. Intraventricular catheters offer the thera- peutic advantage of CSF drainage for treatment of elevated ICP.
Figure 15-5. Continued
C
Figure 15-6. (A) CT showing delayed hematoma in patient involved in a shrapnel injury to base of skull and orbit. (B) Lateral and (C) AP angiogram revealing pseudoaneurysm of anterior cerebral artery. (D) Pseudoaneurysm was treated by endovascular coiling. The patient’s initial angiogram after injury was negative.
B
Hyperventilation reduces ICP through cerebral vasoconstriction, and therefore carries the risk of hypoperfusion from decreased cerebral blood flow. Because of this risk, hyperventilation should be employed sparingly, and only for brief periods while other treatment modalities are instituted.
Figure 15-6. Continued
C
Projectiles can impart various forces on the cerebral vasculature result- ing in arterial wall transection. Depending on the location, the patient may develop a subarachnoid hemorrhage, an intracerebral hematoma, and/or intraventricular hematoma (Figure 15-7). Subarachnoid hemorrhage is seen in 31 to 78% of PHI cases on CT scan.37Both Aldrich and colleagues and Levy and colleagues have shown that the presence of subarachnoid hemorrhage correlates significantly with patient mortality.38,39
Ten percent of combat-related PHIs are associated with dural sinus involvement.40This can lead to massive intraoperative hemorrhage. When the trajectory of the projectile raises the potential of dural sinus injury, preoperative planning should include appropriate hemodynamic support, including blood products and air embolism monitoring, availability of proper equipment, and personnel familiar with surgical techniques for managing venous sinus injury.
Figure 15-6. Continued D
Figure 15-7. (A) CT of GSW revealing small
intraparenchymal hematoma, intraventricular hemorrhage, and a large subdural hematoma with marked mass effect.
(B) CT of shrapnel wound with small intraparenchymal
hematoma. B
A
Traumatically induced pseudoaneurysms or traumatic intracranial aneurysms (TICA) may occur, with 0.4 to 0.7% of all intracranial aneurysms caused by trauma, 20% of these from PHI.24,37The incidence of TICAs is reported between 3 and 33.3% in PHI patients.24,26,41,42Angiog- raphy is the standard in detection of vascular injuries, but a single angiogram does not rule out the possibility of a TICA.24,26,41Since TICAs are not usually true aneurysms, clipping may not be effective. Endovascu- lar techniques or trapping of the lesion are alternative treatment options.
Seizures are common after PHI. They are typically divided into early and late; early defined loosely in the literature as within the first seven days.
Between 30 and 50% of PHI patients develop seizures. Four to 10% of these are early seizures while 80% occur within the first two years.43,44Data from the VHIS indicated that after 15 years of follow up, nearly 50% of PHI patients with epilepsy stopped having seizures.44If PHI patients do not have seizures within the first three years, 95% will remain seizure free.45 Few studies exist that examine only PHI patients and the use of prophylactic antiepileptic drugs. The current guidelines extrapolated from those patients with nonpenetrating traumatic brain injury recommend antiepileptic drugs during the first week to prevent early posttraumatic seizures. No data sup- ports the use of these medications prophylatically beyond the first seven days in the PHI population to prevent late posttraumatic seizures.46
Penetrating head injury wounds are considered contaminated, both superficially and deep. Negative pressure from the cavity caused by the projectile can draw superficial contaminant and debris deep into the wound.
The primary projectile, either bullet or fragment, that remains intracranial is not sterile; insufficient heat is generated from the firing mechanism and high velocity for adequate sterilization.47,48Broad-spectrum antibiotics are initiated as soon as possible. In civilian PHI, coverage for Staphylococcus and Streptococcus should be of primary concern. With military combat injuries, coverage should also include Acinetobacter, and may be further broadened depending on the area of operations.49,50
Surgical Management
The foundation for surgical management of PHI is found in the work per- formed by Cushing during WWI: craniectomy, thorough debridement of devitalized scalp, bone, brain, metal and bony fragments, and meticulous closure. This approach remained relatively unchanged through Vietnam.
Data from the VHIS and modern military conflicts do not support vigor- ous removal of all bone and metallic fragments or repeat craniotomies solely for removal of additional fragments. Debridement should be confined to nonviable brain, with removal of readily accessible fragments of bone and metal.51
Brain Injury for similarly selected patients.
The early identification and evacuation of hematomas is important in effecting the outcome of PBI. Some authors have stated that the only indi- cation for surgery, outside of wound care, is the reduction of mass effect, and thus intracranial pressure, from a hematoma.33,54The rapid evacuation of hematomas creating significant mass effect is the standard practice. If a hematoma is not removed in a salvageable patient, ICP monitoring should be considered to confirm the decision and to guide further therapy.
All PHI patients should be evaluated vigorously and monitored contin- uously for the presence of a CSF leak. In a report based on the VHIS, only 50% of CSF leaks were located at the wound site. The remaining were assumed to be caused by injury from the projectile’s concussive effect.32 Mortality for these patients was 22.8% versus 5.1% for those without a CSF leak. The presence of a CSF leak is the variable most highly correlated with intracranial infection in PHI patients. In the VHIS, 44% of the fistulas closed spontaneously.55 However, if the leak is persistent or delayed in onset, treatment with either CSF diversion or direct surgical repair should be instituted. During any primary surgical treatment of PHI a meticulous, watertight closure of the dura, including the use of temporalis fascia, fascia lata, or graft material, is essential.
Air sinus injuries present an increased risk for CSF leak, especially with an orbital-facial wound. Analysis of a two-year period during the Korean War revealed a 15% incidence of air sinus injury with combat PHI.56Delay in repair of this injury increases the risk of infection.7,8,10,56Management may include craniotomy and anterior fossa reconstruction, exoneration of the frontal sinus, and watertight dural closure. For temporal bone injuries, a mastoidectomy or middle ear exploration with Eustachian tube packing may be required.
Postoperative Care
Postoperatively, the patient is monitored in an intensive-care setting. As mentioned, ICP is monitored and treated for a goal ICP of less than 20 mmHg and CPP of greater than 60 mmHg.36Any persistent, unexplained
elevation in ICP or deterioration in neurologic status warrants an emergent CT scan of the head to identify a new mass lesion, most typically a delayed hematoma. A new hemorrhage after surgery should raise the suspicion of an underlying vascular injury or coagulopathy. In certain cases, typically young patients with nondominant hemisphere lesions, a decompressive craniectomy, and duroplasty may be considered in refractory increased intracranial pressure.
The development of hydrocephalus is another potential complication. In a patient with a ventriculostomy, the inability to wean over 7 to 14 days with persistent high CSF outflow at normal pressure is a good indication the patient will need CSF diversion. Hydrocephalus also may develop in a delayed fashion with a slowly deteriorating neurological exam. If the CT reveals ventriculomegaly, including an enlarged fourth ventricle with no focal mass effect, a lumbar puncture may be performed to record an opening pressure. The final timing for definitive CSF diversion is determined by the presence of other injuries, nutritional status, and infectious complications.
The presence of fever, elevated white cell count, and meningeal signs are concerns for postoperative meningitis. If a ventriculostomy is in place, CSF may be sent for laboratory inquiry. In addition to evaluating the ICP mon- itoring system, a thorough examination for a CSF fistula should be per- formed. Not all CSF leaks are present on admission. In a review of the VHIS, 72% of CSF leaks appear within the first two weeks of injury.55
In the initial evaluation and postoperative period, a coagulation panel should be evaluated, as PHI is a known etiology for coagulopathy. The brain parenchyma contains thromboplastin that can activate the extrinsic coagu- lation cascade. If high levels are released, the patient may develop a dis- seminated intravascular coagulopathy (DIC). Because the degree of the coagulopathy is related to the amount of thromboplastin released from injured tissue, the presence of DIC represents a large area of parechymal injury and portends a worse prognosis.19,57
As discussed above, the patient should remain on antiepileptic medica- tion for seven days post injury for the prevention of early seizures. Antibi- otics generally are used for a 7 to 14 day course for isolated PHI. A longer duration may be required based on systemic infection or other complicat- ing factors.
Prognosis
In comparing outcomes with PHI patients and those with nonpenetrating traumatic brain injuries, PHI patients fare worse. They have an overall mor- tality of 88%, compared to 32.5% in nonpenetrating traumatic brain injury.38,58Typically, death occurs soon after the injury, with 70% occurring within the first 24 hours.58An accurate assessment of prognosis for each
patients are in their second to third decade.58
In the civilian population, gunshot wounds are the most common type of PHI, with a majority of these being suicide attempts. Suicide PHIs are asso- ciated with a higher mortality.58 The question has been raised whether suicide outcomes are based on the injury pattern or the degree of resusci- tation based on the belief of a worse outcome.59This pattern is different in military PHI, where fragmentation injuries instead of gunshot wounds, are found in those patients who survive transport to higher echelons of care.
The high velocity associated with military bullet wounds typically causes a devastating intracranial wound. One series reported a mortality with this wound to be 82% higher than with fragmentation wounds.14
Given the velocity, and hence the amount of energy imparted by a pro- jectile to achieve a perforating wound, it is not surprising that these injuries are associated with the highest mortality. While no statistically significant data exists, penetrating wounds tend to have a higher mortality than tan- gential.58 Surprisingly, there does not tend to be a correlation between outcome and caliber of weapon. This is likely because the energy imparted to the tissue is also related to the velocity, which can be quite variable.58
From the patient’s presentation and neurological status, several poor prognostic indicators can be determined. Systemic insults after a PHI can worsen the patient’s outcome. Periods of hypotension, respiratory distress, and the presence of a coagulopathy are all associated with increased mor- tality.58 From a neurologic perspective, the patient’s GCS is one of the strongest predictors of mortality and outcome.58 In civilian settings, most patients present with a GCS of 3 to 5. These patients have the highest rate of mortality and poor outcome. In military series, more patients present with GCS of 13 to 15, and thus have a better outcome. This reflects more fragment injuries, a more rigid field triage system, and a slower evacuation system. An abnormal pupillary exam is common after PHI and can result from orbital trauma, medications, cerebral herniation, or brainstem injury.
Patient who present with unequal or fixed and dilated pupils have an increased mortality.58There is little data that exists on the prognostic value of ICP in PHI. What is available suggests that elevated ICP within the first 72 hours predicts higher mortality.58
As previously discussed, a CT scan is the diagnostic modality of choice.
Three prognostic indicators can be determined from the patient’s initial scan: projectile track, evidence of increased ICP, and the presence of hem- orrhage or mass lesion. Projectile trajectories associated with increased mortality include bihemispheric lesions, multilobar lesions, and those that involve the ventricular system. One exception may be a bifrontal injury.
Basilar cistern effacement on CT, indicative of elevated ICP, is associated with increased mortality. Midline shift alone, however, is not. The presence of large contusions and/or subarachnoid hemorrhage is associated with increased mortality. A stronger correlation, however, exists between increased mortality and the presence of intraventricular hemorrhage.58
Given these prognostic indicators, the provider must decide on who would benefit from surgery and aggressive management. Grahm and col- leagues reported on 100 consecutive cases of gunshot wounds to the head in an attempt to answer this question.18No patient with a postresuscitation GCS of 3 to 5 and only 20% of those with GCS of 6 to 8 had a satisfactory outcome, defined as either good or moderately impaired on the Glasgow Outcome Scale. From their experience, they recommend that all patients with gunshot wounds to the head be resuscitated aggressively and trans- ferred to a trauma center. Patients with a large, extraaxial hematoma, despite their GCS, should undergo surgical therapy. In those patients without a hematoma and a GCS of 3 to 5, no further treatment should be offered. In patients with a GCS score of 6 to 8 and transventricular or dom- inant hemisphere multilobar injuries in the absence of an extraaxial hematoma, further treatment should not be offered. A patient with a GCS of 6 to 8 without these findings on CT and all those with GCS of 9 to 15 should be offered aggressive therapy, as this is the population with the best chance at a satisfactory outcome.18
The management of the patient with ballistic trauma to the head requires aggressive resuscitation and accurate triage based on clinical and CT findings. When surgical intervention is required, strict attention must be paid to the principles of watertight dural closure and wound coverage after an adequate debridement of devitalized tissue and easily accessible frag- ments is completed. Aggressive intensive care unit management includes avoidance of hypotension, hypoxia, control of ICP and CPP, use of antibi- otics and anticonvulsants, and vigilant monitoring for CSF fistulas and pseudoaneurysms. Unfortunately, this current era of terrorist threats man- dates that all physicians should have a basic understanding of ballistic trauma to the head.
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