Concussion: Causes, Symptoms, and Epidemiology

• Concussions result from brain injury caused by biomechanical forces that disrupt normal brain function, due to either direct or indirect force to the head.
• Concussions are primarily functional injuries caused from shear stress, not structural damage to the brain.
• This injury typically causes a rapid onset of short-lived neurological impairment that resolves spontaneously.
• Evolving symptoms may emerge over minutes to hours.
• Loss of consciousness may occur in concussions.
• Concussions have classifications of mild, moderate, and severe.

Concussion Epidemiology

• 2.8 million Traumatic Brain Injury (TBI)-related injuries happen per year.
• There are 2.5 million Emergency Department (ED) visits related to TBIs each year.
• About 282,000 hospitalizations occur per year.
• There are 50,000 deaths per year.
• Between 2007-2013, TBI-related ED visits decreased by 47%, hospitalization rates decreased by 2.5%, and death rates decreased by 5%.

Etiology/Pathophysiology of Concussions

• Concussions are often caused by a closed head injury from a bump, shock, or jolt.
• A direct blow to the head, face, neck or somewhere else in the body can cause a concussion.
• Concussions can lead to impaired neurotransmission, loss of ion regulation, deregulation of energy use and cellular metabolism and reduced cerebral blood flow.
• Concussions can sometimes be overlooked on radiography imaging because of absent structural damage.

Mild Traumatic Brain Injury (TBI)

• Involves reported loss of consciousness for less than 30 minutes.
• Confusion and blunted affect can occur.
• Pain, dizziness, and headache are common symptoms.
• Changes to sleeping patterns occur.
• The patient may experience visual disturbances like seeing stars, or blurry/double vision.
• Amnesia can be pre-traumatic (retrograde) or post-traumatic (antegrade) with mild TBI.

Severe Traumatic Brain Injury (TBI)

• Involves loss of consciousness for longer than 30 minutes.
• Post-traumatic amnesia may last longer than 24 hours.
• Increased intracranial pressure signs include persistent vomiting, worsening headache, increased disorientation, and a changing level of consciousness.

Common Clinical Presentations of Concussions

• Difficulty thinking clearly
• Feeling slowed down
• Difficulty remembering new information
• Inability to focus
• Headache
• Fuzzy or blurry vision

Concussion Physical Exams

• An exam should be performed immediately after the injury if present.
• Check the patient's ABC's as well as cervical spine stabilization if it is needed.
• Focus observations on the patient's level of consciousness, oxygen saturation, vital signs, and Glasgow Coma Scale score calculation.
• Extremities should be checked for symmetry in movement and any injuries.
• Perform a quick but thorough neurological exam (after awakening if loss of consciousness has occurred.)
• Immediate ER evaluation may be needed.

Additional Physical Exam Focus Areas

• Prior head injuries should be noted.
• Protective Mechanisms and Equipment should be assessed.
• Vision should be assessed.
• Hearing should be assessed.
• Balance should be assessed.
• Neck pain should be assessed.
• Tingling/loss of sensation should be assessed.
• Assess Reflexes
• Assess Memory
• Assess Concetration
• Assess the ability to recall information.
• Check for Racoon eyes (skull fracture).

Glasgow Coma Scale (GCS)

• The scale rates eye, verbal and motor responses, from best to worst.
• Eye opening responses range from 4 (spontaneous) to 1 (no opening).
• Verbal responses range from 5 (oriented) to 1 (no response).
• Motor responses range from 6 (obeys commands) to 1 (no response).

Head Injury Severity Scale (HISS)

• Mild head injury is indicated by GCS = 13-15, associated with loss of consciousness or amnesia for less than 1 hour.
• Moderate head injury is indicated by GCS = 9-12, associated with a loss of consciousness for up to a day.
• Severe head injury is indicated by GCS less than or equal to 8, associated with loss of consciousness for more than 24 hours.

Concussion Diagnostics

• History and Physical is the most important diagnostic tool.
• CT scan of the head without contrast is the standard test to rule out serious brain injury.
• CT scans should be done on patients with loss of consciousness and one of the following: headache, vomiting, age >60 years, trauma evidence above the clavicle, post-traumatic seizure, short term memory loss, or GCS score <15.
• MRI is a secondary test for further detail if needed.

Concussion Differentials

• Acute stress /Post traumatic stress disorder (PTSD)
• Depression
• Headache syndrome
• Seizure disorder
• General trauma or injury to the rest of the body no involving the head

Non-Pharmacological Concussion Management

• Goal is cognitive rest for 24 hours-7 days.
• Focus on physical injury care as needed.
• Treat with ice, massage, and rest in a dark room for pain management.
• Educate about avoidance of: Caffeine, Alcohol, Nicotine, Exercise, Stress, Electronics and Video Games.

Pharmacological Concussion Management

• Focus on symptom management
• Tylenol 325 mg PO Q4-6H can provide some relief for mild pain.
• Tylenol 500mg extra strength PO Q4-6H can provide some relief for moderate to severe pain.
• Zolpidem 5mg PO QHS can improve sleep (use 5mg for females and 10mg for males).
• Lunesta 1-3mg PO Q HS can improve sleep.
• Sleep maintenance with Benzodiazepines should be avoided because it may mask CNS symptoms.
• NSAIDs must be avoided unless a bleed has been definitively ruled out.

Concussion Geriatric Considerations

• Falls are the most common cause of TBI among elderly individuals.
• Patients over the age of 75 years have the highest rates of both TBI-related hospitalization and death.
• Imaging should be considered for patients older than 65 years of age, even in the absence of loss of consciousness.
• Imaging should be considered for all patients on blood thinners who sustain a head injury.

Concussion Follow-Up/Education

• Specialty care referral should be made if there is no symptoms resolution after 2-3 weeks
• Immediate medical attention should be sought for worsening headache, weakness, numbness or decreased coordination, repeated vomiting or nausea, slurred speech, drowsiness, one pupil that is larger than the other, convulsions or seizures, and increased confusion, restlessness, or agitation
• Clearance to return to school can be given once patient can concentrate for 35-45 minutes with no difficulty (adjustments to environment should be made as needed)
• Clearance to play sports can be given when patient has been asymptomatic for 24 hours with no medications

Concussion Prevention

• Encourage the use of helmets, mouth guards, and seatbelts.
• Utilize the CDC “Heads up” campaign for youth and athletes as a resource.
• Implement fall prevention measures particularly for those with gait impairments, which should include adequate lighting, removal of clutter, installation of grab bars/hand rails, walking aids, and adequate footwear should be ensured.