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7. CRANIAL TRAUMA AND ICU MANAGEMENT Gary Simonds ead trauma is a commonly encountered diag nostic problem in neurosurgery and is thought by some to be relatively limited in its technical challenges. By rights, head trauma cases should therefore be straightforward opportunities to pick up steam in the examination. The more command the test taker has over a subject, the more confidence he or she will build and store for perhaps more challenging questions. It is therefore wise to review and master the subject in preparation. I  would advise paying particular attention to published head injury guidelines.1 I would also practice describing surgery for the major traumatic head injuries in detail and contemplat ing the many associated complications that might occur. Articulating the procedure out loud to oneself will make the experience more familiar and less anxiety provoking in the examination. Consider describing the surgical portion of your response as you would in an operative dictation. If this becomes too tedious for the examiners, they will fastforward you to another stage of the case. CASE 1 HISTORY AND PHYSICAL EXAMINA TION A previously healthy 18- year- old woman is involved in a motor vehicle collision in which she is thrown through a windshield at high speed and sustains multiple trauma. She arrives by helicopter intubated. She has significant facial trauma and swelling. She is in a coma. Her best motor response is reported to be decorticate. Her right eye is dilated and unresponsive. Her left pupil is normal and responsive to light, and she has a brisk corneal response. IMAGING STUDIES Right pneumothorax and several fractured ribs are seen on the chest radiograph. ANALYSIS OF CASE AND TREA TMENT PLAN Stop for a moment and take a deep breath and think! This may not be a surgical case at all. No surgical lesions have been given to you, although you are concerned about the dilated right pupil. This might be a closed head injury management question. Do not run to the operating room quite yet— start with the basics. W e know that airway and breathing are controlled, but what is the blood pressure? 80/ 40 mm Hg. Heart rate is 120 beats/ minute. So first things first:  this patient needs to be resuscitated, and you might mention we have not ruled out a spinal cord injury, although this does not sound like spinal shock because of the elevated heart rate. The trauma team gives her 2 L of lactated Ringer’s solution, and she responds well. Laboratory tests including a toxin and pregnancy screen are requested. The trauma team performs a survey, and you evaluate for any other neurological findings, but they are obfuscated by sedatives and paralyzing agents. Next stop then would be computed tomography (CT) scan of the brain as part of the CT trauma survey, which will include cervical, thoracic, and lumbar imaging. The mechanism of injury and lack of an obtainable spinal cord neurological examination warrant this. (Please do get the spine imaging— we had this very case this week, and the patient had a horrific T6- T7 fracture dislocation!) CT of the brain shows scattered deep white matter punctate hemorrhages with no mass lesions or mass effect. Cisterns are “tight.” The right orbit shows multiple frac tures (Figure 7.1). Direct trauma to the globe or optic nerve may explain the dilated pupil rather than a cranial nerve III palsy. The CT scans of the spine are negative. SAMPLE QUESTIONS AND REASONABLE ANSWERS What Do Y ou W ant to Do Next?

ions or mass effect. Cisterns are “tight.” The right orbit shows multiple frac tures (Figure 7.1). Direct trauma to the globe or optic nerve may explain the dilated pupil rather than a cranial nerve III palsy. The CT scans of the spine are negative. SAMPLE QUESTIONS AND REASONABLE ANSWERS What Do Y ou W ant to Do Next? I would like to make sure the patient goes to an intensive care unit (ICU) and is stabilized (no hypotension or hypoxia),

ions or mass effect. Cisterns are “tight.” The right orbit shows multiple frac tures (Figure 7.1). Direct trauma to the globe or optic nerve may explain the dilated pupil rather than a cranial nerve III palsy. The CT scans of the spine are negative. SAMPLE QUESTIONS AND REASONABLE ANSWERS What Do Y ou W ant to Do Next? I would like to make sure the patient goes to an intensive care unit (ICU) and is stabilized (no hypotension or hypoxia), 62 • G OODMAN ’S N EUROSURGERY O RAL B OARD R E v IEW and I would like to place a right frontal ventriculostomy for intracranial pressure (ICP) measurement and control. The patient thus far has a Glasgow Coma Scale (GCS) score of less than 8 and an abnormal CT of the head. Why not a simple parenchymal ICP monitor? V entriculostomies allow for cerebrospinal fluid (CSF) drainage to assist in ICP control. They also can be readily recalibrated, allowing ICP monitoring without the inher ent “drift” that parenchymal systems are prone to. Prolonged use of a ventricular catheter is relatively well tolerated with low incidence of infection, particularly since the introduc tion of antibiotic- impregnated catheters. What is angular acceleration with reference to head injury? Head injury victims can be subjected to a number (and mix) of forces in a traumatic incident. If the head is subjected to linear acceleration- deceleration, the brain moves within the head linearly and can collide with the surrounding skull. This can result in contusions of the poles at various surfaces, but unless the forces are extreme, leaves the bulk of the brain without too much injury. Angular acceleration or rotational acceleration means the head is rapidly turned on its axis. Because of differentials in brain density, this can result in a “wringing” motion of the cerebrum on the brainstem, stretching, damaging, and tearing millions of axons. This can result in the dif fuse injury of neurons throughout the brain with terrible sequelae and is known as diffuse axonal injury. Of course, someone thrown through a car windshield at high velocity is subjected to all sorts of horrific forces in combination. OK— the ICP is 44 mm Hg. What do you want to do? I would like to initiate a series of maneuvers and interven tions to bring the ICP to below 20 mm Hg if at all possible. These would include raising the head of the bed, assuring no constriction around the neck with the head in a neutral position, performing intermittent CSF drainage as neces sary, sedating lightly to prevent V alsalva maneuver and coughing (fighting the endotracheal tube), administering judicious intravenous fluids with no free water or dilute solutes (use, for example, normal saline), and considering employment of concentrated normal saline or mannitol— although I  generally use mannitol when the ICP will not respond to other measures. INTERRUPTION (this is common)… . Should you hyperventilate the patient? No, particularly in the early stages of injury, this would be contraindicated unless no other measures were working and we were headed toward a more aggressive intervention such as barbiturate coma or surgery and wanted to use hyperventilation as a temporizer. Why not? Hyperventilation lowers Paco 2, which results in vasocon striction and may contribute to further local and regional injury of traumatized brain. The head- injured patient appears to be particularly vulnerable during the first 24 hours after the trauma. Case 1-DAI Figure 7.1 A, B: Non– contrast- enhanced computed tomographic scans of the brain in an 18- year- old who is in a coma after a motor vehicle collision.

er local and regional injury of traumatized brain. The head- injured patient appears to be particularly vulnerable during the first 24 hours after the trauma. Case 1-DAI Figure 7.1 A, B: Non– contrast- enhanced computed tomographic scans of the brain in an 18- year- old who is in a coma after a motor vehicle collision. C RANIAL T RAUMA AND ICU M ANAGEMENT • 63 Should you “dry the patient out” with diuretics? No, although diuretics may indeed lower ICP, they also create a hypovolemic state, which may compromise perfusion of damaged regions of brain as well as contribute to cardiovascular instability. Should you give anticonvulsants? I generally would, although this is debatable. Acute use of anticonvulsants in traumatic brain injury will lower the chances of early seizures but will not lower the rate of late or downstream seizures. They can also have side effects. I gen erally administer 1000 mg of levetiracetam (Keppra) twice daily in the acute phase of severe brain injury. What cerebral perfusion pressure do you aim for? If possible, I would like to get the cerebral perfusion pres sure (CPP) to the 50- to 70- mm Hg range, ideally around 60 mm Hg. Why? W e know that in acute head injury, a CPP of 50 mm Hg and lower or of 70 mm Hg and higher is asso ciated with worse outcomes. CPP higher than 70 mm Hg is associated with greater systemic complications, and CPP lower than 50  mm Hg is associated with poorer neuro logical outcomes. Patients without elevated ICP and with intact autoregulation tolerate a wider range. How much dexamethasone (Decadron) will you give? Steroids are contraindicated in the care of patients with severe closed head injuries— I would not use any. The CRASH study demonstrated a significant increase in mortality after a 48- hour infusion of methylprednisolone after closed head injury.2 COMPLICA TIONS ICPs are well controlled for a day, and you are called because they suddenly have shot back up into the high 40s. What do you want to do? I would evaluate the patient and make sure the ventriculostomy is working and is calibrated correctly. I would look for straightforward reasons for the elevation (e.g., neck kinked, low sodium/ hypervolemic, hypoventilation, sei zure, coughing and V alsalva). I  would evaluate the neu rological status for new lateralizing findings that might indicate a developing expanding intracranial lesion. I would initiate ICP- lowering administrations. If I  did not have a readily identifiable and reversible reason, I would take the patient to CT to rule out a new mass lesion. CT scan shows that a good 1 cm of your ventricular catheter is in the left thalamus. What should you do? If the catheter is working well with good CSF access and waveforms, I would leave it in. Y ou also see a 2- cm hematoma around the catheter in the right frontal lobe. What should you do? If the ICP is well controlled, I would leave the hematoma alone and follow it. If the ICP is uncontrollable, I  might consider evacuation as a component of a decompressive craniectomy. CASE 2 HISTORY AND PHYSICAL EXAMINA TION A previously healthy 19- year- old man is involved in a motor vehicle collision in which he is thrown through a windshield at high speed and sustains multiple trau mas. At your center, he undergoes a full trauma evalua tion and resuscitation. He is in coma with symmetrical flexor posturing to noxious stimuli. CT scan of the brain shows scattered deep white matter petechial hemor rhages, “tight cisterns, ” and no space- occupying lesions or shift (Figure 7.2). CT scans of the spine are normal. In the ICU, a ventriculostomy was placed.

tion and resuscitation. He is in coma with symmetrical flexor posturing to noxious stimuli. CT scan of the brain shows scattered deep white matter petechial hemor rhages, “tight cisterns, ” and no space- occupying lesions or shift (Figure 7.2). CT scans of the spine are normal. In the ICU, a ventriculostomy was placed. ICPs were in the 40- mm Hg range, and your team has struggled to lower the ICP using positioning, CSF drainage, sedation with propofol and low- dose pentobarbital, hypertonic saline, and even some limited hyperventilation to no avail. The electroencephalogram (EEG) shows slowing but no sei zure activity. ICP is 45 mm Hg, CPP is 60 mm Hg, serum sodium level is 152 mEq/ L, Pco 2 is 34 mm Hg. A repeat CT scan of the brain is performed. What do you want to do next? IMAGING STUDIES The CT scan of the brain is essentially unchanged from the original, with only a small amount of “blossoming” (expansion) of petechial hemorrhages. A ventricular catheter sits

g, serum sodium level is 152 mEq/ L, Pco 2 is 34 mm Hg. A repeat CT scan of the brain is performed. What do you want to do next? IMAGING STUDIES The CT scan of the brain is essentially unchanged from the original, with only a small amount of “blossoming” (expansion) of petechial hemorrhages. A ventricular catheter sits 64 • G OODMAN ’S N EUROSURGERY O RAL B OARD R E v IEW in the appropriate position in the right frontal horn of the lateral ventricles. ANALYSIS OF CASE AND TREA TMENT PLAN This is an example of a case for which there is no defini tive single answer to the problem. There is no class I evi dence to guide your answer. There is class II evidence that argues for and against surgical intervention. DO NOT play a game of guessing what the examiners are thinking! Put yourself in the situation described and go ahead with what you would do in your institution and be prepared to defend it. Resorting to barbiturate coma (pentobarbital 10 mg/ kg load over 30 minutes, then 5 mg/ kg/ hr for three doses, then 1 mg/ kg/ hr) with burst- suppression EEG (or serum levels of 3– 4 mg%) would be a viable alternative to surger y. At our institution, we have a somewhat light trigger to go to decompressive craniectomy, particularly in young patients without evidence of associated severe hypoxic injury. From here, the most appropriate type of craniectomy also is not well delineated. W e tend to perform bifrontal craniectomy for diffuse symmetrical injuries and hemicraniectomy when one side has a preponderance of contusions or extraaxial hematoma. No matter your choice, be prepared to describe the procedure “from skin to skin.” SAMPLE QUESTIONS AND REASONABLE ANSWERS So, what do you want to do? I think we are failing to control ICP with aggressive maneuvers, although we are maintaining a good CPP. With this young patient who was originally flexor on examination, I  would resort to decompressive craniectomy to assist in ICP control. Why not try “pentobarbital coma?” I think barbiturate coma is an option and can be quite effective in lowering ICP, but it depresses functions throughout the body and can lead to significant systemic complications. It also might delay definitive ICP reduction through cra niectomy. Furthermore, it completely obfuscates the neu rologic examination, often for a prolonged period of time. Craniectomy will usually lower ICP to acceptable levels immediately, allowing for earlier assessment of the neuro logical examination. What kind of craniectomy do you plan? With neither side of the brain bearing the brunt of con tusions, and no substantial extraaxial collections, I  would perform a bifrontal decompressive craniectomy with duraplasties. OK, take us through it. I would transfer the patient to the operating room and position the patient supine with the table in reverse T rendelenburg. After an appropriate “prep and drape, ” I  would initiate a full time- out— INTERRUPTION… . (Note: It is good to be very descriptive about your proce dures, but be prepared for the examiner to cut you off and fast- forward you to the components of the procedure he or she wants to hear.) What kind of incision will you make and where will you place your bur holes? I would make a bicoronal incision behind the coronal suture and reflect the scalp anteriorly down to the orbital rims. I usually place bur holes 2 cm behind the coronal suture on either side of midline and anteriorly above the orbital rims. I also may place a single bur hole bilaterally 2 to 3 cm below the temporalis insertion over the tem poral fossa. (Y ou will have a model to demonstrate these locations.) Case 2-DAI Figure 7.2 Non– contrast- enhanced computed tomographic scan of the brain in a 19- year- old who is in a coma after a motor vehicle collision.

so may place a single bur hole bilaterally 2 to 3 cm below the temporalis insertion over the tem poral fossa. (Y ou will have a model to demonstrate these locations.) Case 2-DAI Figure 7.2 Non– contrast- enhanced computed tomographic scan of the brain in a 19- year- old who is in a coma after a motor vehicle collision. C RANIAL T RAUMA AND ICU M ANAGEMENT • 65 OK, then what do you do? I will use a Penfield dissector #3 to separate the dura from the skull, particularly over the sagittal sinus. I will then raise a single craniotomy flap using a footplated side- cutting drill. When the flap is raised, I will pass it off for deep freezing. I will then open the dura in a cruciate fashion, flapping one component toward the sagittal sinus. I will evaluate the brain for evacuable lesions and bleeding and obtain meticulous hemostasis. I will then use a dural substitute to cover the exposed brain and lightly re- reflect the patient’s own dura over it. Usually, I  place bilateral subdural drains and bring them out of distant stab incisions posteriorly. I then close the scalp in multiple layers. How far behind the coronal suture is the motor strip? Approximately 5 cm. On the head surface, where approximately is the sylvian fissure? Along a line from the lateral canthus to a point three fourths of the way along a line from the nasion to the inion. (Note: this type of question is not “make or break” for the exam but could come up as a probe of your knowledge depth.) Where is the angular gyrus? Just above the pinna. COMPLICA TIONS Y ou make your craniotomy, and you notice you entered the frontal sinus. What do you do? If it is a small opening and the mucosa is intact, I would use bone wax to seal it. If it is a large opening with torn mucosa, I would have to exenterate it, pack the ostia with temporalis muscle, eventually flap a pedicle- based pericranial flap over it, and seal it with fibrin glue. In raising your craniotomy flap, you see profound bleeding from the sagittal sinus. How do you handle this? I would ask for greater reverse T rendelenburg position ing and apply gentle compression over the sinus with sheets of thrombin- soaked Gelfoam and large Cottonoid pads. If this controlled the bleeding, I would inspect for large rents. What if you open your dura and initially the brain appears relatively relaxed, but as you are preparing to close the brain, it suddenly starts swelling? I would ask for increased reverse T rendelenburg position ing. I  would ask the anesthesiologists if something had changed significantly on their side. Are we ventilating appropriately? Is there a kink in the endotracheal tube? What are the end- tidal Po 2 and P co 2? Is the patient fully anesthetized? I  would ask for some hyperventilation and 25 g of mannitol. I would inspect the brain for evidence of regional extraaxial or intraparenchymal bleeding. W e could even inspect using ultrasound. Actually, your patient does well, and the ICPs immediately come under good control, until the next morning, when the nurse calls you and states that the ICPs are up in the 50s. What will you do? I would evaluate the patient immediately. I would make sure the ICP monitor was functioning appropriately. Raise the head of the bed, make sure there is no kinking or compression of the neck, make sure the ventilator is working appropriately, make sure the patient is ventilating well. Initiate ICP control measures, remove any potentially constrictive head wraps, and feel the decompression flap for fullness. If there were no obvious explanations, I would obtain a stat CT scan of the head. CASE 3 HISTORY AND PHYSICAL EXAMINA TION A previously healthy 21- year- old man is in your trauma bay with a gunshot wound to the head. Preliminary trauma evaluation and resuscitation have been com pleted.

decompression flap for fullness. If there were no obvious explanations, I would obtain a stat CT scan of the head. CASE 3 HISTORY AND PHYSICAL EXAMINA TION A previously healthy 21- year- old man is in your trauma bay with a gunshot wound to the head. Preliminary trauma evaluation and resuscitation have been com pleted. He is intubated. There is a small round scalp wound in the right forehead and a ragged laceration in the right parietal occipital region with bone fragments and brain material in the adjacent hair. There is no active bleeding. The patient does not open his eyes or follow commands but does reach toward noxious stimulus with the right hand. He is hemiplegic on the left. The right pupil is dilated and unreactive, and the left pupillary function is normal. IMAGING STUDIES CT scan of the brain demonstrates a 2.5- cm diameter holohemispheric right subdural hematoma with mass effect and

ollow commands but does reach toward noxious stimulus with the right hand. He is hemiplegic on the left. The right pupil is dilated and unreactive, and the left pupillary function is normal. IMAGING STUDIES CT scan of the brain demonstrates a 2.5- cm diameter holohemispheric right subdural hematoma with mass effect and 66 • G OODMAN ’S N EUROSURGERY O RAL B OARD R E v IEW 3 cm of midline shift. There are some scattered contusion and boney fragments along a track through the high right hemisphere (Figure 7.3). ANALYSIS OF CARE AND TREA TMENT PLAN Management of gunshot wounds to the brain is contro versial and will vary between institutions. Patients with a very low GCS score and bihemispheric injuries or very low projectile trajectories are often treated expectantly. But this is a case that really leads to a surgical solution. The examiners likely want to hear your surgical manage ment and are presenting you with a young patient who has a large space- occupying hematoma and is localizing with an injury to the nondominant hemisphere— it is OK to go to surgery. In gunshot wounds to the head, initial medical maneu vers are similar to those for severe closed head injury— elevate the head of bed, ventilate, use judicious amounts of higher osmolarity fluids, consider mannitol and hyper tonic saline, and keep the neck unrestricted. Entry and exit wounds should be shaved and inspected. Bleeding should be controlled. In this case, the patient should be rapidly prepared for surgery. Remember, there will be no single correct way to perform the surgery— describe the surgery as you would perform it if you had to at your institution. SAMPLE QUESTIONS AND REASONABLE ANSWERS So, what do you want to do? I would make sure the patient is stabilized and resuscitated working with my trauma colleagues as quickly as possible and would head emergently to the operating room for sur gical decompression of the hematoma and debridement of the gunshot wounds. Where would you make your incision and craniotomy? I would perform a large trauma flap. This would entail a large right frontotemporoparietal question- mark– shaped inci sion that would be flapped anteriorly with the temporalis musculature. (Remember: you will have a model of the head to demonstrate this.) The incision would either include or incorporate the posterior scalp laceration from the bullet. I would make bur holes in the “key point, ” in the temporal fossa just above the zygoma and far posteriorly in the pari etal region. I would raise as large a frontotemporoparietal Case 3-GSW with SDHC ase 3-GSW w/SDH Figure 7.3 A, B: Non– contrast- enhanced computed tomographic scans of the brain in a 21- year- old who sustained a gunshot wound to the head. Not pictured are slices of the right brain that showed scattered contusion and bony fragments along a track in the high right hemisphere, with no retained bullet.

se 3-GSW w/SDH Figure 7.3 A, B: Non– contrast- enhanced computed tomographic scans of the brain in a 21- year- old who sustained a gunshot wound to the head. Not pictured are slices of the right brain that showed scattered contusion and bony fragments along a track in the high right hemisphere, with no retained bullet. C RANIAL T RAUMA AND ICU M ANAGEMENT • 67 craniotomy flap as possible from the bur holes, approaching to within 1.5 cm of the midline. Y ou evacuate the hematoma and control bleeding. What do you do about the bullet track? I would inspect the entry and exit sites in the brain. I would debride clearly macerated, pulped, devitalized tissue at these sites and evacuate any sizable coalesced contusions or hematomas, but would not aggressively pursue the track deep into the brain or try to debride every fleck of skull from its depths. Why not? Aggressive debridement of the track and small skull frag ments has not ben shown to lower infection rates and may damage viable tissue or precipitate bleeding in difficult- toaccess depths. What if there were a large fragment of bullet three fourths of the way through the track? There is some argument to remove large, readily accessible bullet fragments because of their propensity to migrate. Will you replace the bone flap? Generally, I do not. Aggressive decompressive craniectomy was shown to be of benefit in military gunshot wounds to the head, although it may be of less benefit in lower velocity civilian cases. Gunshot wounds are prone to postoperative swelling and increased ICP. I therefore usually perform the procedure as a decompressive craniectomy and place a ventriculostomy for postoperative ICP monitoring. What is the difference between a high- velocity and low- velocity bullet wound to the brain? Low- velocity bullets injure the most immediate tissue to their track through direct mechanical trauma (tearing, contusing). High- velocity rounds cause direct injury as well, but also cause distant injury through shock waves and cavitation. Thus, brain injury is generally far more extensive and severe. Are there any other postoperative concerns? Sure, there are many. Postoperative hemorrhage must be watched for. Seizures are not uncommon, and I use prophylactic phenytoin (or other anticonvulsants, such as Keppra, 1000 mg twice daily) although this has not been shown to reduce late- onset “downstream” seizures. Infection is a major concern to include meningitis but also deep brain abscess. I  tend to use prophylactic antibiotics (cefazolin [Ancef ]) for 1 week, although this regimen is not well established. There is also a risk for traumatic aneurysm formation, and I tend to obtain a vascular study about 5 days after injury, particularly if the bullet traversed near major intracranial vasculature. How do you handle a surface vessel that is “pumping” out hemorrhage? I generally tamponade it with a Cottonoid pad. I then peel back the Cottonoid until I can see the vessel clearly without bleeding and use bipolar electrocautery to eliminate the bleeding. I usually then leave a piece of thrombin- soaked Gelfoam over the site. (Examiners may want to hear your straightforward surgical techniques— these are not trick questions!) What do you do about hematoma along the sagittal sinus or that is coursing into the interhemispheric fissure? Generally, I do not “chase” hematoma all the way up to the sinus or into the interhemispheric fissure unless it is very large. This region tends to bleed a fair amount with manipulation, and there is a risk for damaging important draining cortical veins. I prefer to leave a light covering of hematoma in the region and to pack thrombin- soaked Gelfoam along it before closing.

e sinus or into the interhemispheric fissure unless it is very large. This region tends to bleed a fair amount with manipulation, and there is a risk for damaging important draining cortical veins. I prefer to leave a light covering of hematoma in the region and to pack thrombin- soaked Gelfoam along it before closing. COMPLICA TIONS Surgery is going well, but as you are cleaning up the exit site of the brain, you notice increased bleeding from all plains, and the blood has a dilute Kool- Aid– type appearance. What is going on? I would be very concerned about disseminated intravascu lar coagulation (DIC), which can occur in massive head injuries. It is thought to be related to a large- scale release of tissue thromboplastin and other procoagulants. It results in consumption of platelets and components of the coagu lation cascade. It can result in diffuse bleeding from “raw” sites, and this can be very difficult to combat mechanically (through surgical maneuvers). How would you handle this? I would seek to minimize any further surgical manipula tion of tissue and obtain mechanical hemostasis as best

ts and components of the coagu lation cascade. It can result in diffuse bleeding from “raw” sites, and this can be very difficult to combat mechanically (through surgical maneuvers). How would you handle this? I would seek to minimize any further surgical manipula tion of tissue and obtain mechanical hemostasis as best 68 • G OODMAN ’S N EUROSURGERY O RAL B OARD R E v IEW as possible. I  would ask for assistance from my anesthesia colleagues in the manner of transfusion of appropriate supportive materials such as platelets, fresh frozen plasma, and cryoprecipitate. I would seek to obtain hemostasis and close up as soon as possible with no further manipulations. The patient does well and regains consciousness and some movement on the left side. One week out, he develops a descending rigidity from his face down. He then develops diffuse spasms set off by the lightest stimuli. Any ideas? My first thought would be meningitis, and I would obtain CSF for culture either by ventriculostomy if it is still in place or by lumbar puncture if the CT scan appears benign. One other thought might be to question the trauma team and the emergency department about whether the patient received a tetanus toxoid shot on admission— this presentation has the markings of tetanus. (Note: This is a “way out there” question, but the examiners may have wanted to hear about tetanus toxoid administration in the initial manage ment of the patient. If so, they will make it obvious.) CASE 4 HISTORY AND PHYSICAL EXAMINA TION A 17- year- old male high school football player is knocked unconscious during a game. He “comes to” in less than a minute and sits on the bench for the remainder of the half. He slumps over onto a teammate and is found to be unresponsive. At your center, he is found to be hemiplegic on the right with a left dilated and unreactive pupil. He localizes with his left side but does not open his eyes or follow commands. IMAGING STUDIES Pending. ANALYSIS OF CARE AND TREA TMENT PLAN This has all the markings of a classical traumatic brain injury syndrome, but you should not jump to conclusions immediately. Address the case as if you were arriving at the emergency department to find the patient unattended. The examiners may want to hear components of your initial evaluation and management. They will move you along to the “meat” of the case. W ork through the case in an orderly, succinct, and efficient manner. SAMPLE QUESTIONS AND REASONABLE ANSWERS So, what do you want to do? I would make sure the patient was attended to reference airway, breathing, and circulation. If he were not intubated, he would need to be so. I would ask my trauma colleagues to evaluate for other major injuries and to resuscitate the patient as needed. This would be considered a full “trauma code.” I would complete my initial neurological survey and then proceed to imaging. What images do you want? I would want a CT scan of the head as soon as possible because I suspect an intracranial hematoma with mass effect and herniation. I would also want CT studies of the entire spine, particularly the cervical spine, because of my inability to fully evaluate the patient. CT scan of the spine is OK. CT scan of the brain reveals a left epidural hematoma. What would make you bring the case to surgery? Guidelines suggest that an epidural hematoma (Figure 7.4) with a volume greater than 30  cm 3 should be evacuated no matter what. Other criteria that lean one toward sur gery would include thickness greater than 1.5 cm, associ ated focal neurological deficits, GCS score of less than 9, and midline shift greater than 5 mm. Anisocoria and GCS score of less than 9 suggest the need for immediate surgery.3 How do you measure epidural hematoma thickness?

her criteria that lean one toward sur gery would include thickness greater than 1.5 cm, associ ated focal neurological deficits, GCS score of less than 9, and midline shift greater than 5 mm. Anisocoria and GCS score of less than 9 suggest the need for immediate surgery.3 How do you measure epidural hematoma thickness? A decent estimate of volume is thickness times length times height divided by 2. What is Kernohan’s notch phenomenon? This is known as a false localizing sign. With temporal lobe (uncal) herniation, the brainstem (cerebral peduncle) can be pushed against the contralateral incisura (temporal notch), causing ipsilateral rather than contralateral hemiparesis. This patient has a 2.5- mm thick epidural hematoma on the left side. What do you want to do? This patient needs to go to surgery immediately for emer gent evacuation of the hematoma.

l peduncle) can be pushed against the contralateral incisura (temporal notch), causing ipsilateral rather than contralateral hemiparesis. This patient has a 2.5- mm thick epidural hematoma on the left side. What do you want to do? This patient needs to go to surgery immediately for emer gent evacuation of the hematoma. C RANIAL T RAUMA AND ICU M ANAGEMENT • 69 The operating room says it will be 2 hours before the next neurosurgical room is available. I would argue that this is not acceptable. Survival in this situation is time dependent. The longer the herniation is allowed to transpire, the higher the chances of irreversible brainstem injury. This is a bona fide emergency, and a room needs to be made available, preferably within minutes. What if there were a flood in the operating room or a mass casualty situation, or you were out in the “boonies”— where would you put your bur holes if you had to perform a life- saving procedure in the emergency department? Evacuation of an epidural or subdural clot can be prob lematic because of the consistency of the hematoma. In a desperate situation, however, such a maneuver could be life threatening. The first choice for a generous bur hole placement would be over the middle fossa to obviate uncal herniation. This bur hole would be created just above the zygomatic arch and just anterior to the ear (through tem poralis muscle). Another bur hole should be located over the thickest portion of the hematoma. Classical teaching talks about creating trauma bur holes in the advent of similar clinical findings to this case but with no brain imaging available. Here, the first bur hole would be placed over the middle fossa as described previously, ipsilateral to the side of the dilated pupil. If no epidural hematoma is found, the dura should be opened. If this is negative, a second bur hole would be made over the middle fossa on the other side (in case of a falsely localizing Kernohan’s notch phenomenon). If this is negative, two further bur holes can be made on the side ipsilateral to the dilated pupil over the parietal and frontal lobes. What procedure will you perform? I will perform a frontotemporal craniotomy centered on and encompassing the width of the hematoma. (Be pre pared to demonstrate your incision and describe your opening, hematoma evacuation, and closure.) What will you do to prevent reaccumulation of hematoma? I would make sure there is meticulous hemostasis of the field. I use hemostatic agents on the field such as thrombinsoaked Gelfoam. I usually place a small drain and bring it out of a separate stab incision. I would 4- 0 Nurolon dural tack- up sutures circumferentially and centrally in the craniotomy field. How do you do this? I make small “wire- passing” holes in the bone surrounding the craniotomy defect. I pass the suture through the outer layer of the dura immediately adjacent to the bone edge and then through the circumferential holes and tightly tie the dura up to the bone edges. I would also place one or two tack- up sutures in the center of the dural field and bring them up through holes in the craniotomy flap. These are tied taught after the craniotomy flap is secured in place. So, you replace the bone flap? Y es, almost always. Why almost always? Epidural hematomas are generally not associated with sig nificant underlying diffuse injury, so we generally do not anticipate severe brain swelling and ICP. If the underlying brain is full and tight, something else is going on. Do you almost always replace the bone flap in a subdural hematoma evacuation? If not, what is the difference? The mechanism of injury is often different between the two.

iffuse injury, so we generally do not anticipate severe brain swelling and ICP. If the underlying brain is full and tight, something else is going on. Do you almost always replace the bone flap in a subdural hematoma evacuation? If not, what is the difference? The mechanism of injury is often different between the two. Generally, epidural hematomas arise from focal trauma with Case #4-EDH Figure 7.4 Non– contrast- enhanced computed tomographic scans of the brain in a 17- year- old who was injured while playing football and is now in a coma.

iffuse injury, so we generally do not anticipate severe brain swelling and ICP. If the underlying brain is full and tight, something else is going on. Do you almost always replace the bone flap in a subdural hematoma evacuation? If not, what is the difference? The mechanism of injury is often different between the two. Generally, epidural hematomas arise from focal trauma with Case #4-EDH Figure 7.4 Non– contrast- enhanced computed tomographic scans of the brain in a 17- year- old who was injured while playing football and is now in a coma. 70 • G OODMAN ’S N EUROSURGERY O RAL B OARD R E v IEW little diffuse brain injury. They are more often the result of torn vessel than brain pulping. On the other hand, subdu ral hematomas are often associated with more profound traumatic forces and more extensive brain injury. The brain may be pulped and abraded, causing surface bleeding that coalesces into a subdural hematoma. Even with evacuation of the subdural hematoma, the diffusely injured brain may be too swollen to replace the bone flap. What, then, are your criteria for evacuation of an acute subdural hematoma? There are many factors that go into the decision to evacu ate a subdural hematoma. Many subdural hematomas are small compared with the adjacent brain injury and thus will be followed unless ICPs become unmanageable. Guidelines suggest that clots of thicker than 10 mm thick ness with greater than 5  mm of midline shift should be evacuated. They also suggest evacuation for smaller clots when the GCS score drops by 2 points, the pupils are asymmetrical, or ICPs cannot be lowered medically below 20 mm Hg. 4 In surgery for acute subdural hematoma, do you always leave the bone flap out? No. I prefer to replace it. I go by the swelling of the brain. If the brain looks in good shape and is relaxed with the hematoma evacuation, I replace the flap over subdural drains. If the brain is particularly pulped up and swollen, I will per form a duroplasty and leave the craniotomy flap out. What kind of outcomes do you anticipate in the two types of hematomas? If the epidural hematoma is caught early enough, particu larly in a patient with a lucid interval history, the patient can make a spectacular recovery, although a small percent age of these patients die or are left in coma. (Run a broad gamut of responses depending on the original injury and timing.) COMPLICA TIONS Y our patient does great during surgery and is awake and alert without deficit within 2 hours. He is extubated. The following morning you are called because he is unresponsive with fixed and dilated pupils. What do you do? I would evaluate the patient (Note: Please DO NOT order a CT scan from your breakfast table!) I would assess his airway and vitals and potentially intubate as needed. I would assess his neurological examination and his operative site and drains. He is rigid throughout with labored breathing and clutched teeth. He then starts rhythmic jerking of the upper extremities. What now? He is likely seizing. I would ask the nurse how long he had been this way and ask for an intubation team to head to the patient’s room (it is likely this has been going on for some time and the patient is in status. I  would place an oxygen mask and make sure he has appropriate intrave nous access. I would have electrolyte and blood chemistries drawn. Thiamine and glucose are given to a new patient in the emergency room without a known history but would not be strongly indicated in this setting. I would adminis ter 0.1 mg/ kg of lorazepam initially (2- 4 mg total). I would repeat if no response after a minute. At the same time, I would be starting 20 mg/ kg of phenytoin in the form of fosphenytoin. This does not stop the activity. What next? I would go to a third- line drug but also be preparing for intubation and the infusion of a continuous drug. Phenobarbital has been the standby third- line drug, although we have employed levetiracetam, 20 mg/ kg by intravenous bolus, owing to its ease of access and low complication profile.

op the activity. What next? I would go to a third- line drug but also be preparing for intubation and the infusion of a continuous drug. Phenobarbital has been the standby third- line drug, although we have employed levetiracetam, 20 mg/ kg by intravenous bolus, owing to its ease of access and low complication profile. W e would intubate and begin an anesthetic drip, usually propofol (again owing to the ease of access), although midazolam is often used. I would ask my anesthesia and neurology colleagues for assistance here. W e would initiate continuous EEG monitoring. As soon as it was deemed safe to transport the patient, I  would want a CT scan of the brain to rule out a new structural intracranial event. CASE 5 HISTORY AND PHYSICAL EXAMINA TION A 25- year- old woman in good health runs into a tele phone pole with her car. She arrives at your center awake but with left hemiparesis. She is conversant but amnestic of the accident. She has facial abrasions and a seat- belt abrasion across her chest. Preliminary trauma evaluation is negative for major injuries. She is alert. Her speech and cranial nerve functions are intact. Her right- sided func tion is normal.

enter awake but with left hemiparesis. She is conversant but amnestic of the accident. She has facial abrasions and a seat- belt abrasion across her chest. Preliminary trauma evaluation is negative for major injuries. She is alert. Her speech and cranial nerve functions are intact. Her right- sided func tion is normal. C RANIAL T RAUMA AND ICU M ANAGEMENT • 71 IMAGING STUDIES CT scan of the brain reveals a 4– × 5– × 3- cm intraparenchymal hematoma in the deep frontal lobe with some associated intraventricular blood. There is local mass effect and 1 mm of midline shift (Figure 7.5). ANALYSIS OF CARE AND TREA TMENT PLAN Be careful here. This is presented as a trauma case but does not have to be. The examiners may want to make sure that you understand that not every presentation is straightfor ward. The classical case is a similar story with a CT scan that shows a subarachnoid hemorrhage very consistent with an aneurysmal hemorrhage. The motor vehicle collision may be a bit of a red herring— the patient experienced an intracranial event that caused her to run into a stationary object (we see a few of these every year). The case presented here is not mounting up to be a surgical problem, and the hem orrhage is not in a classical trauma location, so keep your antenna up. Perhaps the patient sustained a spontaneous intracerebral hemorrhage and ran into the telephone pole. She cannot remember if a headache or other symptoms preceded the collision. SAMPLE QUESTIONS AND REASONABLE ANSWERS So, what do you want to do? I would want to obtain more of a history. Does she remember anything before the accident? Had she ever had any previous syncopal events or seizures? What is her overall health status? Is she hypertensive? Does she take any medications or illicit drugs? I  would obtain a drug screen. Although this hematoma may be of traumatic origin, I would have to worry about a spontaneous intraparenchymal hemorrhage precipitating her motor vehicle collision. I  would want a vascular study, probably computed tomographic angiogra phy (to begin with, but I might eventually want a full fourvessel angiogram. What criteria would lead you to surgery in a patient with a traumatic intraparenchymal hemorrhage? Guidelines (level III evidence) suggest that surgical evacuation of hematoma would be indicated for patients with neurological deterioration and a hematoma with mass effect or a hematoma volume of greater than 50 cm3. Surgery is also considered when the patient has a GCS score of less than 8 and a hematoma larger than 20 cm3 with a midline shift greater than 5 mm and with or without compression of the basilar cisterns.5 Case # 5-IPH from avm Case # 5-IPH from avm Case # 5-IPH from avm Case # 5-IPH from avm Figure 7.5 A– D: Computed tomographic scans of the brain in a 25- year- old who is awake but hemiparetic after a motor vehicle collision.

th a midline shift greater than 5 mm and with or without compression of the basilar cisterns.5 Case # 5-IPH from avm Case # 5-IPH from avm Case # 5-IPH from avm Case # 5-IPH from avm Figure 7.5 A– D: Computed tomographic scans of the brain in a 25- year- old who is awake but hemiparetic after a motor vehicle collision. 72 • G OODMAN ’S N EUROSURGERY O RAL B OARD R E v IEW How common is delayed traumatic intracerebral hemorrhage? This is not an overly common phenomenon (estimated to occur in 10% to 20% of severe head injury patients) but can occur within the first few days of hospitalization. Delayed hemorrhage can result in the need for surgical evacuation and can occur spontaneously or in a region of previous hematoma or contusion. Because of the risk for delayed hemorrhage, most patients with severe head injuries, par ticularly those with intracranial findings on original CT, undergo delayed CT scans 1 to 3  days into their hospital izations. Patients with deterioration on their neurological examination should also undergo repeat CT to evaluate for this phenomenon. What are the most common causes of spontaneous intracerebral hemorrhage in a nonhypertensive patient of this age? Arteriovenous malformation, aneurysm rupture, illicit drug use, and tumor. What if the hemorrhage was quite peripheral near a sinus? I would suspect possible sinus thrombosis. How do you treat sinus thrombosis? Judicious anticoagulation, hydration, and close observa tion would be the initial treatment of sinus thrombosis. Interventional endovascular methods are available for extreme cases but have limited outcomes. COMPLICA TIONS This patient turned out to have an arteriovenous malformation and after a couple of hard seizures was started on phenytoin (Dilantin). T wo weeks later, you are called to your emergency depart ment because the patient has presented there with confu sion, ataxia, and nystagmus. What is going on? These are signs of phenytoin toxicity. I would hold her phenytoin and obtain a serum level. I would not necessarily obtain an emergent CT scan if her level were high (>20 mcg/ mL). She presents again to your emergency department a month later with fatigue, fever, and a sore throat. On inspection, she has ulcers and vesicular lesions of her mucous membranes. She has a diffuse red- purple rash on her trunk and extremities. Is this the flu? This sounds like Stevens- Johnson syndrome, also known as toxic epidermal necrolysis. This is a life- threatening condition and is a form of which will require admission and emergent dermatology evaluation. CASE 6 HISTORY AND PHYSICAL EXAMINA TION A 30- year- old female equestrian in good health is kicked in the head by a horse. She is temporarily knocked uncon scious but has a normal neurological examination on presentation. She has a curved laceration over her right parietal region. The edges appear dirty and a bit macerated. IMAGING STUDIES CT scan of the brain reveals a 4– × 5- cm region of comminuted skull fracture in the right parietal region (Figure 7.6). The greatest depth of infolded fragments is 2 cm. There is a small amount of intracranial pneumocephalus and some surrounding contusion of the brain without any midline shift. ANALYSIS OF CARE AND TREA TMENT PLAN This is an open depressed skull fracture. Like most trauma scenarios, there is a range of options available in the gen eral treatment of depressed skull fracture— be prepared to discuss them in adults and children. Do not guess what the examiner wants— go with what you would do and have a reason why. Open depressed skull fractures will likely require some level of cleaning up and repair. Y ou will have to take it from there! SAMPLE QUESTIONS AND REASONABLE ANSWERS So, what do you want to do? I think this case requires surgery.

n. Do not guess what the examiner wants— go with what you would do and have a reason why. Open depressed skull fractures will likely require some level of cleaning up and repair. Y ou will have to take it from there! SAMPLE QUESTIONS AND REASONABLE ANSWERS So, what do you want to do? I think this case requires surgery. Guidelines support sur gery for open depressed skull fractures, particularly if the

n. Do not guess what the examiner wants— go with what you would do and have a reason why. Open depressed skull fractures will likely require some level of cleaning up and repair. Y ou will have to take it from there! SAMPLE QUESTIONS AND REASONABLE ANSWERS So, what do you want to do? I think this case requires surgery. Guidelines support sur gery for open depressed skull fractures, particularly if the C RANIAL T RAUMA AND ICU M ANAGEMENT • 73 depression is greater than 1 cm, there is evidence of dural laceration, and there is the potential for gross contamina tion. Other criteria not involved in this case might be sig nificant associated hematoma, frontal sinus involvement, and significant cosmetic deformity.6 How would you perform the surgery? W e do not need to hear about positioning, time out, and preparation. I would try to incorporate the laceration into my incision and would give myself a width of skull around the fracture site. I  would inspect the site and check for mobility of the fragments. If they cannot be mobilized, I would make an adjacent bur hole and would slide a Penfield dissec tor under the fragments and deliver them up to curettes or grasping instruments. I  might have to drill further along the periphery of the fracture to affect full mobiliza tion. I  would soak the fragments in bacitracin solution, although there are discussions in the literature of soaking them in betadine. After the fragments were clear, I would inspect the underlying dura, which I presume is lacerated. I would open the dura further so that I could evaluate the underlying brain. I would want to conservatively debride clearly macerated tissue and any contaminants in the field. I would ensure meticulous hemostasis. I would then irrigate profusely with bacitracin. I often use surgical: an oxidized cellulose polymer (the unit is polyanhydrogluc uronic acid) on the injured brain for hemostasis and its bactericidal and static qualities. I  would close the dura and tack it up circumferentially with 4- 0 Nurolon sutures. I  would then determine whether the bone fragments could be reconstructed with simple microplating. If not, or if they appeared hopelessly contaminated, I would dis card them and close after further thorough irrigation. So, you would consider replacing the comminuted bone. What about infection? There appears to be no increased risk for infection in replacing the fractured bone compared with discarding the bone. Using the bone would therefore potentially obviate a sec ond surgery. Nonetheless, when the bone is grossly contaminated, I discard it. W ould you use antibiotics? Level III evidence suggests that antibiotics should be used for open depressed skull fractures. I  generally employ a broad- spectrum antibiotic for 1 week to 10 days. When should the surgery be carried out? The sooner the better. I generally classify it as a non– lifethreatening emergency. Case # 6-open depressed skull fracture Figure 7.6 Non– contrast- enhanced computed tomographic scans of the head of a 30- year- old who is alert after being kicked in the head by a horse.

10 days. When should the surgery be carried out? The sooner the better. I generally classify it as a non– lifethreatening emergency. Case # 6-open depressed skull fracture Figure 7.6 Non– contrast- enhanced computed tomographic scans of the head of a 30- year- old who is alert after being kicked in the head by a horse. 74 • G OODMAN ’S N EUROSURGERY O RAL B OARD R E v IEW Are your indications for surgery the same for closed depressed skull fractures? I tend to be more conservative and limit surgery to cases of significant cosmetic deformity, deep laceration of the dura and brain, significant associated brain injury or hemor rhage, and neurological deficits. How about in a child? Depressed fractures in young children will often smooth out as the skull grows, so deformity is even less of a driver. What about the propensity for seizures? There is no evidence that elevation of depressed skull frac tures will reduce the incidence of seizures. It is not an indication for surgery. What about a “ping- pong ball” depressed fracture? These usually occur in very young children and also will usually smooth out spontaneously over time. In general, these are “greenstick” fractures and should not have bone shards to lacerate the dura. If there were lacerated dura and CSF leak or associated neurological deficit, the fracture could be elevated. If you did have to elevate a ping- pong ball fracture, how would you do it? T raditional descriptions involve making a small bur hole adjacent to the depression and then “popping” the depression back out with a Penfield- like dissector under the depression. W e have used a technique in which a small cranial fixation screw is placed into the middle of the depression and pulled on— elevating the depression. The screw is then removed. COMPLICA TIONS What if you have a depressed fracture over the sagittal sinus? I generally would take a more conservative approach to such a fracture. Unless there is a strong indication for surgery, elevating a fracture over the sinus incurs increased risk for substantial bleeding, sinus occlusion, and cortical vein injury. What if there was a “strong” indication for surgery, such as a CSf leak or associated compressive neurological deficit? I would then approach the problem very judiciously with a wide, open exposure and preparation for potential sinus repair. This would include blood ready for transfusion, large- bore intravenous lines, and a central line. A  Fogerty catheter should be available for temporary occlusion. Ideally, I would isolate the bone over the sinus away from the remainder of the depressed fragments and could potentially leave the fragments over the sinus alone and elevate the remainder of the fracture separately. REf ERENCES 1. Brain T rauma Foundation; American Association of Neurological Surgeons; Congress of Neurological Surgeons. Guidelines for the management of severe traumatic brain injury. J Neurotrauma. 2007;24(Suppl 1):S1– 106. Erratum in J Neurotrauma. 2008;25(3): 276– 278. 2. Edwards P, Arango M, Balica L, et al. Final results of MRC CRASH, a randomised placebo- controlled trial of intravenous corticoste roid in adults with head injury- outcomes at 6  months. Lancet. 2005;365(9475):1957– 1959. 3. Bullock MR, Chesnut R, Ghajar J, et  al. Surgical management of acute epidural hematomas. Neurosurgery. 2006;58(3 Suppl):S7– 15; discussion Si– iv. 4. Bullock MR, Chesnut R, Ghajar J, et  al. Surgical management of acute subdural hematomas. Neurosurgery. 2006;58(3 Suppl):S16– 24; discussion Si– iv. 5. Bullock MR, Chesnut R, Ghajar J, et  al. Surgical management of traumatic parenchymal lesions. Neurosurgery. 2006;58(3 Suppl): S25– 46; discussion Si– iv. 6. Bullock MR, Chesnut R, Ghajar J, et  al. Surgical management of depressed cranial fractures. Neurosurgery.

urgery. 2006;58(3 Suppl):S16– 24; discussion Si– iv. 5. Bullock MR, Chesnut R, Ghajar J, et  al. Surgical management of traumatic parenchymal lesions. Neurosurgery. 2006;58(3 Suppl): S25– 46; discussion Si– iv. 6. Bullock MR, Chesnut R, Ghajar J, et  al. Surgical management of depressed cranial fractures. Neurosurgery. 2006;58(3 Suppl):S56– 60; discussion Si– iv.