CM II - NEURO 7 - head injury

what is a concussion?

mild form of traumatic brain injury (direct blow to the head is not required)

result of the impact forces that created them, both linear and rotational → stretching and tearing of neurons/axons → metabolic cascade

in concussions, what is the metabolic cascade characterized by?

• axonal dysfunction caused by swelling and rupture

• release of excitatory neurotransmitters

• ionic shifts

• generation of oxidizing free radicals

• increased glycolysis

• altered cerebral blood flow

what are coup-contrecoup brain injury?

type of traumatic brain injury occurring when brain injured at site of impact AND on the opposite side of brain

what most commonly causes coup-contrecoup brain injuries?

acceleration-deceleration injuries (whiplash injury)

what is a whiplash injury?

causes combination of cervical spine injury and coup-contrecoup TBI that does not require contact with an outside object. whiplash is an injury of inertia

bone impacts brain

what is a dashboard injury?

causes a combination of cervical spine injury and coup-contrecoup TBI resulting from impact with a stationary object. injury of momentum

brain impacts bone

what causes epidemiology of TBI (traumatic brain injury)?

• motor vehicle accidents

• falls

• occupational/recreational accidents

• assaults

what is VOMS?

tests vision, balance, and movement: smooth pursuits, rapid eye movements, near point of convergence, balance vision reflex, visual motion sensitivity

good tool but not a side-line tool d/t the items needed to conduct the test

what are the elements for concussion on the glasgow coma scale?

• measured at approx. 30 minutes after injury

• score: 13-15 = zero/mild brain injury

what are the different categories of glascow coma scale?

• eye opening

• best verbal response

• best motor response

lowest score is 3, highest is 15

what are the EARLY s/sx of concussion?

• confusion/disorientation and amnesia (for peri-injury period) → hallmark of concussion!

• any period of LOC

• HA

• dizziness/vertigo

• N/V

• vacant stare

• delayed verbal expression and receptivity

• inability to focus attention

• slurred/incoherent speech

• gross observable lack of coordination

• imbalance

what are the late findings (days-weeks) after concussion?*

• emotional reaction out of proportion to circumstances

• cognitive disturbances

• sleep disturbances

• mood disturbances (esp depression)

grade 1 concussion looks like?

transient confusion, no LOC, sx resolve in 15 min

grade 2 concussion looks like?

transient confusion, no LOC, concussive sx/mental status abnormalities persist longer than 15 mins

grade 3 concussion looks like?

any LOC, brief (secs) or prolonged (minutes)

what are the red flags in concussions that REQUIRES a CT?*

1. focal neuro deficit

2. seizure

3. presence of bleeding diathesis/anticoag use

4. drug/alc intoxication

5. decreased LOC

6. suspicion of skull fracture (incl. basilar fracture)

   1. GCS < 15, 2 hours after injury, improving/worse

what are the characterizations of basilar fracture seen in traumatic brain injuries?*

characterized by hemotympanum, raccoon eyes (intraorbital bruising), battle’s sign (retroauricular bruising), cerebrospinal fluid leak (oto- or rhinorrhea)

how to decide who goes home vs. hospitalized for a concussion?

if no red flags/normal CT, and responsible caretaker is available on site, pts can be discharged

caregiver must observe closely for 24 hrs checking q2h for

• inability to awaken to pt

• severe/worsening HA

• somnolence/confusion

• restless/unsteadiness/seizures

• difficulties with vision

• vomiting, fever, stiff neck

• urinary/bowel incontinence

• weakness/numbness involving any part of the body

what is the return to school criteria for concussions?

1. tolerate symptoms while doing cognitive activities for 30-45 minutes

2. utilization of adjustments (no change in standardized testing)

3. If symptoms continue beyond 3 weeks → academic accommodations (ie special arrangements for standardized testing)

4. if concussion is prolonged → academic modification (permanent changes)/IEP

what are the stages of return to play criteria?

• stage 1: no activity

• stage 2: light aerobic exercise

• stage 3: sport-specific exercise

• stage 4: non-contact training drills/light resistance training

• stage 5: full contact practice

• stage 6: complete activity in games

what is the 2011 NYS concussion law?

• requires education of coaches, PE teachers, school nurses, and athletic training (best prevention of harmful outcomes)

• immediate removal from play for student athlete

• athlete must complete 6-stage graded protocol

• should not be on meds that mask symptoms

• must be asymptomatic for 24 hrs at each level

what is post-concussion syndrome?

• 3 or more symptoms for > 1 months

• may have post-traumatic headaches, epilepsy, or vertigo

what is a common late symptom following a concussion?

depression

who is at risk for second impact syndrome?

Patients with history of multiple concussions are at especially high risk of developing neurologic sequelae when concussions are “stacked” one upon another without period of time in which they are symptom-free

sx can be more permanent

what can second impact syndrome lead to?

chronic traumatic encephalopathy (CTE), previously called “dementia pugilistica”

what are the s/sx of second impact syndrome?

dementia sx incl. cognitive impairment, memory loss, confusion for years

1. Behavioral and personality changes

2. Depression and suicidality 

3. Parkinsonism and other speech and gait abnormalities are described

when can you diagnose CTE definitively?

definitively diagnosed on autopsy

what is the best prevention for concussions?

• #1: team regulations against rough play

• educating athletes, families, and coaching staff on early diagnosis and eval

to prevent SECOND IMPACT syndrome!!!!!

what doesn’t really prevent concussions?

• helmets

• mouth guards

• external helmet cushions