Authors: H. Hunt Batjer
Tarek Y. El Ahmadieh
Nicole M. Bedros
Traumatic brain injury (TBI) affects more than 1.5 million individuals every year in the United States, leading to 270,000 hospitalizations. The great majority of these injuries consist of a brief change in mental status or a loss of consciousness that lasts less than 30 minutes, and are categorized as concussions. Given the advances in neuro-imaging and the high resolution and widespread availability of computed tomography (CT) scanners, subarachnoid hemorrhage (SAH) is a very common finding in post-concussive patients.
The trauma protocol at most hospitals dictates that TBI patients with a head CT positive for abnormal findings should be admitted for observation for a variable time duration, however consensus in the other aspects of their management is still lacking. Controversial issues include the necessity for admission to the intensive care unit, the need for repeated imaging after a time interval, dealing with patient home antiaggregant and anticoagulant medication, clearance for return to play or return to learn, and management of incidentally-found lesions. While seizure prophylaxis is not routinely recommended in patients with mild TBI regardless of the presence of subarachnoid blood, there are no established randomized controlled trials or protocols in place to guide the management of anticoagulant or anti-platelet medications that patients may have been taking at the time of the injury. These medications can be hazardous, cumbersome, and expensive to stop or reverse, depending on their indication. Reversal requires the administration of blood products and can impose a draining toll on the hospital's blood bank services. Moreover, reversal agents theoretically induce a pro-thrombotic state which can be detrimental and associated with severe adverse effects. Given our aging population, this issue is gaining rapid priority.
In a more delayed fashion, postconcussion syndrome can affect 5% to 30% of patients, and includes cognitive failure, depression, sleep pattern disturbances, and recurrent debilitating headaches. These symptoms, along with knowledge that the trauma was severe enough to cause cerebral hemorrhage, can create significant stress and anxiety for the patient and their family. They can also lead to repeated emergency department re-visits because of recurrent headaches and a fear of ongoing bleeding or seizure-like activity, and be the reason for a loss of productivity and days away from the workplace.
In addition, concussions carry the risk of severe and irreversible neurological injury if they are repeated in tandem. Young patients are particularly vulnerable to this "second impact" phenomenon within two weeks following the initial trauma. Repeated concussions can also lead to chronic traumatic encephalopathy. Heightened social and medical awareness regarding the potentially severe consequences of mild TBI have led to the development of rules regarding return to study for children and young adults, return to play for athletes, and return to active duty for military personnel. The role of the neurosurgeon in this context is to make sure that the initial concussion was not severe enough to prohibit any potential re-exposure, and would not warrant prolonged suspension from return to play that could in extreme cases translate into early retirement. The time for return to school and study should also be weighed carefully, as patients can be at increased risk for prolonged post-concussion syndrome if they are cognitively strained too early.
Finally, modern scanners often reveal incidental lesions that can potentially carry a worrisome prognosis. These include cerebral aneurysms -that can sometimes be the cause of the SAH leading to the trauma and concussion, arteriovenous malformations, cavernous malformations, and benign or malignant tumors. They also include subaxial spine stenosis or trauma that may elude emergency departments, and could potentially lead to subsequent cervical spine injury and myelopathy. These findings often require additional testing and ownership of care by a neurosurgical service for prolonged management and follow-up.
The potential repercussions of concussion mismanagement on the system overall reinforces the role of the neurosurgeon as a gatekeeper for patient care. A neurosurgical opinion can place the patients and their caretakers at ease, by providing expert opinion, follow-up, and counseling that their symptoms will abate despite the presence of SAH, albeit with a prolonged convalescence. It can also provide nonneurosurgical colleagues with reassurance and medicolegal coverage that would enable them to minimize unnecessary or superfluous diagnostic testing, without compromising patient care, while ensuring that incidental findings are addressed appropriately. This paradigm, however, does not require that all TBI patients be transferred to a center where neurosurgical presence is directly available. Telemedicine has been shown to be as efficient as direct neurosurgical involvement in both civilian and military hospitals in the management of these patients after initial triage, and will likely be playing an incremental role in the future.