Concussion is a diagnosis that many emergency physicians will be making multiple times in their career. Oftentimes, patients diagnosed with concussion will only ever be seen by an emergency physician. It is necessary for emergency clinicians to understand the pathophysiology, clinical presentation, evaluation, and management of these patients.

Concussion will have varied presentations with symptoms that typically fall into 4 categories, including somatic, cognitive, emotional/behavioral, and sleep/wake disturbances. Emergency department (ED) providers need to have the knowledge to counsel patients about the spectrum of symptoms that may occur, both immediately and through recovery. There are also standardized tools to help emergency physicians make decisions about necessary imaging for the head and cervical spine. The Standardized Concussion Assessment Tool (SCAT-5) can help guide the ED provider through the history and physical exam to help diagnose the concussion.

Emergency department management mostly focuses on symptom control, as well as counseling. It is reasonable to recommend a 24-48 hour period of rest from the emergency department, and patients should not be cleared to return to play from the ED. Most of these patients will discharged home from the ED, but follow up is necessary. Emergency physicians also need to have an understanding about persistent postconcussion symptoms (PPCS) and recognize patients that may benefit from specialty referral to concussion clinic.

Woods E, Raukar N (2020) Concussion Management in Emergency Departments. Ann Sports Med Res 7(2): 1148.

Most emergency physicians are able to recall seeing a head injury during one of their last shifts as it is a common presenting chief complaint. It is estimated that there are 2.5 million emergency department (ED) visits every year for traumatic brain injury (TBI) [1]. The majority, 75%, of these TBIs are classified as mild and are often only ever assessed by an ED physician [2]. It is prudent that ED physicians understand how to recognize and manage mild TBI or concussion.

The Centers for Disease Control and Prevention (CDC) reports that most of these injuries result from falls, getting struck in the head, and car accidents. These injuries are most likely to occur in older adults (>75 years), teens and young adults (15- 24 years) and young children (0-4 years) [3]. Between 2006 and 2014 TBI has been on the rise, independent of mechanism, with the greatest increase seen in those with unintentional falls, which increased by 80% [3]. Given how common head trauma is, it is important to understand their presentation and are able to appropriately evaluate, manage, counsel and disposition these patients. It is also important to recognize that the majority of these patients will go onto have resolution of their symptoms, but some may have prolonged symptoms that may compromise their quality of life. Emergency physicians play an important role in ensuring appropriate follow up for patients predicted to have a more complicated course by understanding the pathophysiology and predictive factors of a more complicated course.

The pathophysiology of concussion is not easily conceptualized due to the fact there are no characteristic imaging findings or objective blood or cellular biomarkers [4]. It is described that when a mild TBI occurs there is a transient disruption of cellular membranes that leads to the release of neurotransmitters. The disruption of these cellular ion channels and membranes leads to increased glucose metabolism, followed by a period of decreased glucose metabolism. This results in a mismatched supply and demand in terms of energy production and expenditure, typically lasting for 7-10 days [5]. Axonal stretch may also lead to dysfunction although there are no obvious findings of this on imaging modalities [6]. Glutamate and its receptors as well as GABA release and utilization are also altered post concussion [7]. Inflammation has also been implicated in playing a role in concussion [8].

A deep dive into the cellular level causation of post concussive symptoms is beyond the scope of this article but the above described pathophysiology leads to the clinical translation of concussive symptoms such as headache, cognitive deficits, neurobehavioral deficits, slowed reaction time, and motor impairment [7]

Mild TBI is defined as a disruption of brain function resulting from trauma. Patients present with a GCS between 13 and 15 and neurologic symptoms that are typically transient, with no abnormalities on standard imaging. This may be due to a direct hit to the head; however, can be caused by hits to the body or acceleration-deceleration injuries [9]. Patients will typically have immediate onset of symptoms that are mostly functional. These injuries may be associated with loss of consciousness but note, only 10% have a reported loss of consciousness. Concussion typically has rapid onset of symptoms, in minutes to hours, that resolve spontaneously over days. Unfortunately, some patients may have protracted symptoms [10].

Symptoms associated with concussion are typically placed in 4 categories: physical, cognitive, emotional, sleep related [9]. These symptoms can be widely varied and noted in the chart below [11].

In the emergency department, the priority in patients who present with a head injury is to rule out more severe injuries such as skull fractures, intracranial hemorrhage and structural brain lesions. A thorough history helps to understand the specifics of the mechanism of injury and can identify those who require imaging. Since concussed patients can present with a variety of symptoms, a standardized checklist can help organize the symptoms and can be used to trend symptoms over time. Injury factors can influence the duration of symptoms, and patients with prolonged symptoms usually present with amnesia surrounding the event, severe vertigo, severe cognitive symptoms or a high initial symptom burden [10, 12]. A history of previous concussions, migraines, learning disabilities and mental illness puts patients at risk for a prolonged recovery.

Specific tools, such as The Sport Concussion Assessment Tool 5 (SCAT) can be used in the emergency department and has been validated for its use [13]. It can be used in ages 13 and older while children ages 5-12 years can use the Child SCAT [14]. These tools comprise both in-field and off-field assessment portions. The offfield assessment involves: 1) athlete background, 2) symptom evaluation, 3) cognitive screening, including orientation, immediate memory and concentration, 4) neurological screening which includes balance examination, 5) delayed recall and finally 6) decision making. Remember to consider baseline cognitive abilities. Also note that this screening takes no less than 10 minutes. The physical exam maneuvers include complete neurological testing with Romberg testing and cervical spine examination. Other examination maneuvers to be considered are oculomotor testing, using tools such as the Vestibular Ocular Motor Screening (VOMS) Exam. This can be completed and takes about 5 minutes and evaluates 1) smooth pursuits, 2) saccades including horizontal and vertical, 3) convergence, 4) vestibularocular reflex including horizontal and vertical, and 5) visual motion sensitivity [15-17]. The vestibular-ocular reflex has the patient rotate their head about 20 degrees to each direction and maintain focus on a target quickly and about 10 times and the visual motion sensitivity test has the patient hold their arm outstretched in a “thumbs up” position and while focusing on their thumb moves their trunk 80 degrees to the right and left, doing so for 5 repetitions. The ED physician then asks about headache, dizziness, nausea and mental fogginess [16].

Imaging also must be considered when a patient presents to the ED after head injury. There are easily accessible tools designed to help emergency physicians decide who requires imaging of the head and cervical spine. The Canadian Head CT Rule can be used to determine need for CT imaging and includes exclusion criteria, high risk criteria and medium risk criteria. It can be found at: https://www.mdcalc.com/canadian-ct-headinjury-trauma-rule. Notably, the US validation study found it was 100% sensitive for ruling out clinically important injuries and injuries requiring neurosurgery [18]. PECARN Pediatric Head Injury Algorithm can also be used in children to assess the need for further observation in imaging in children. This can be found at: https://www.mdcalc.com/pecarn-pediatric-head-injurytrauma-algorithm. The NEXUS C-Spine Rule can be used to rule out cervical spine injury in those that are alert and stable without need for further imaging (https://www.mdcalc.com/nexuscriteria-c-spine-imaging ) [19] Other rules such as the Canadian C-Spine Rule (https://www.mdcalc.com/canadian-c-spinerule) [20], can also be used and is theoretically more sensitive and specific than NEXUS rules, but is also more complex. Use of validated tools such as those mentioned can help to prevent overimaging of emergency medicine, which is especially necessary in our pediatric patients presenting with head injury.

After deciding that the patient is likely suffering from a concussion it is important for the emergency physician to provide counseling. Symptomatic treatment, while important, is best accomplished in the acute phase with rest. While considering treatment for the headache, it is important to balance symptom control with rebound phenomenon seen with giving frequent and prolonged medications [21]. Treatment should focus on rest and allowing medications only sparingly.

It has long been the cornerstone of counseling concussed patients to recommend rest; however, evidence has been conflicting in regards to the duration of rest recommended and the exact definition of “rest” for these patients [22-24]. The are multiple proposed benefits behind the recommendation for cognitive rest. It decreases the likelihood of possibility of additional injury, especially in those who may want to return to playing sports. There is also suggestion that rest may lessen the severity of symptoms patients are experiencing while they recover from mild TBI. One study, found that a brief period of rest, such as 24-48 hours, is appropriate for most patients but the exact amount and duration beyond that has not been defined and needs further investigation [25]. Societies, such as the American Academy of Pediatrics [26] and American Medical Society for Sports Medicine [27], have differing recommendations regarding return to school and return to activity, but don’t provide specifics, rather calling for individualized approach to management based on the patient’s symptoms [28]. In the acute phase, it is appropriate to recommend rest. A retrospective chart review study found that only 12% of ED physicians recommended cognitive rest in their discharge instructions [29]. There have been multiple trials that have compared recommendations of strict bed rest to usual return to play, but their outcomes have been conflicting [28,30,31]. Current CDC recommendations are for 24-28 hours of cognitive and physical rest, with re-introduction of activities as tolerated gradually. It is recommended that if these activities do not worsen these symptoms, they can be advanced through introduction of activities [32].

Disposition decisions for those with moderate to severe TBI are often easier for emergency clinicians to make as the majority of patients will be admitted to the hospital. However, disposition decisions when it comes to mild TBI or concussion are less clear. Even though these patients will be discharged, these is lack of consensus regarding timing of follow up after discharge from the emergency department. One study noted that 48% of people who had persistent symptoms had not had any type of follow up appointment for 3 months after their injury and those who have access to specialty follow up, such as a concussion clinic, have higher utilization of follow up [33]. It is believed that since the mortality associated with these injuries is not high, these patients get triaged to not be seen right away. It is important that the ED counseling include instructions to also follow up with their primary care provider within one week for appropriate symptom assessment.

ED physicians can help set up appropriate outpatient management of concussions, can provide important initial information, and offer reassurance to patients and their parents. Evidence shows that initial education and counseling may have a positive role in patient recovery from concussion and minor head injury [34].

Patient education is of the utmost importance for patients with mild TBI. There are handouts available through the CDC at: https://www.cdc.gov/traumaticbraininjury/pdf/tbi_patient_ instructions-a.pdf. It is necessary to discuss decision making in regards to imaging, restriction of activities, reasons to return to the emergency department, reasons and timeline for follow up in the outpatient setting.

Emergency physicians must have understanding of Persistent Post-Concussion Symptoms (PPCS) as these patients may present initially or month’s later if the patient is still experiencing symptoms. PCCS is thought to be secondary to brain injury plus psychological and social factors. Treatment recommendations for this condition include education, reassurance, exercise, cognitive behavioral therapy, and specific concussion rehabilitation programs [35].These patients would likely benefit from referral to specialized concussion clinic as this requires a multidisciplinary approach [35,36,37]

Emergency physicians will certainly encounter concussion in their day to day practice. It is important to understand the varied presentations of this syndrome and be able to counsel patients about the wide variety of symptoms that may occur. There are standardized tools and physical examination maneuvers that can help assess the severity. There are also standardized tools to help you make decisions about necessary imaging.

ED management mostly focuses on symptom control, with a 24-48 hour period of rest from the emergency department. Most of these patients will be discharged home from the ED, but strict return precautions for worsening or new symptoms and primary care follow up are necessary.

Some patients may experience PPCS and may return to the ED. These patients benefit from referral to a concussion clinic where a multidisciplinary approach can be utilized.

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