TBI -6209

An alteration in brain function or diagnostic evidence of brain pathology, usually caused by an external force

Traumatic Brain Injury (TBI) definition

The number one cause of TBI

Falls

-Male gender

-Childhood/adolescence and Older age

-Alcohol and/or Drug exposure

-Baseline neurologic or psychiatric conditions

-Functional impairment (weakness, gait dysfunction)

-Lower socioeconomic status

-Combat and military service

Risk Factors for TBI

Results from EXTERNAL MECHANICAL forces transferred to brain:

-Direct impact

-Rapid Acceleration and/or Deceleration of Head

-Rotational force

-Penetrating injury

Primary Brain Injury Pathophys

Molecular injury occurring from time of initial trauma that continues for hours to days:

-Ischemia

-NT-mediated excitotoxicity, causing glutamate, free-radical injury to cell membranes

-BBB disruption

-Mitochondrial dysfunction

-Electrolyte imbalance

-Inflammatory response

-Apoptosis and Necrosis

Secondary Brain Injury Pathophys

-Cerebral Edema

-Cerebral Infarction

-Delayed Hemorrhage

Possible Damage after TBI

Inflammatory response and disruption in BBB that causes excess fluid in brain

Cerebral Edema

May occur due to Cerebral Autoregulation Failure, DEC'd Perfusion Pressure, or Direct Vascular Injury

Cerebral Infarction

Coagulopathy (inability of blood to clot) associated w/ INC'd risk of bleeding

Delayed Hemorrhage

-Eye opening

-Verbal response

-Motor response

Domains of Glasgow Coma Scale (GCS)

-Performed at bedside

-Has 3 domains

-Scored between 3 and 15 points → Lower = more SEVERE

-Controversial to rely on for prognosis !!

Glasgow Coma Scale

GCS 3-8

→ SEVERE TBI

GCS 13-15

→ MILD TBI

-Vacant stare

-Delayed verbal expression

-Inability to focus

-Disorientation (physical and mental)

-Slurred or incoherent speech

-Excessive emotional rxns/outbursts

-Memory deficits

-Vertigo

-Nystagmus (uncontrollable rapid eye movement)

Signs/Sx of TBI

This is preferred for ACUTE phase of Head Trauma; all patients with a GCS score of ≤14 or lower ** → NEED THIS

CT Imaging

Occurs when brain tissues move form one part of the brain to another due to swelling or elevated ICP (intracranial pressure)

Cerebral Herniation Pathophys

-Unilateral or Bilateral Fixed & Dilated Pupils

-Respiratory depression

-"Cushing Triad" (HTN, Bradycardia, and Irregular respiration)

Signs of Cerebral Herniation

All patients w/ GCS BELOW <9 who are UNABLE to protect airway / MAINTAIN SpO2 > 90 even w/ supplemental O2

→ Endotracheal Intubation

→ Single dose of Ceftriaxone 2g IV

Why do we give a single dose of Ceftriaxone 2g IV to patients w/ GCS <9, unable to protect airway/maintain SpO2? (during cerebral herniation)

DEC risk of ventilator-associated pneumonia (VAP)

Upon arrival to ED for a TBI/Cerebral Herniation, following resuscitation, and in absence of sedation, we do:

Neurologic exam w/ GCS

This reduced ICP and therefore is used for managing Cerebral Herniation

Mannitol 20% Solution, 0.5-2g/kg IV infused over 10 min q4-6 hrs PRN

Important note for Mannitol solution IV infusion

Can crystallize, so we need to inspect prior (can redissolve by warming solution)

Indicated for patients w/ moderate TBI (GCS 9-12) who present to hospital WITHIN 3 HOURS of injury

Anti-Fibrinolytic Therapy

Tranexamic Acid 1g IV infused over 10 min, followed by 1g IV over 8 hours

antifibrinolytic therapy to use (shows lower risk of head-injury related death in CRASH-3 trial)

-Isotonic fluids (normal saline) for Euvolemia

-Maintain SBP ≥100 for ppts 50-60 y/o and ≥110 for ppts 15-49 or >70 y/o

-Cerebral Perfusion Pressure (CPP) goal of 60-70 mmHg

Hemodynamic Management in TBI

Mean arterial pressure (MAP) - Intracranial pressure (ICP)

CPP calc

-GCS score <11

-Penetrating head wound

-Cortical confusion visible on CT scan

-Seizure within 24 hrs of injury

-Subdural/epidural/intracerebral Hematoma

Risk Factors of Posttraumatic Seizures in TBI ppts

-Reduces incidence of early seizures

-DOES NOT prevent development of epilepsy later

Anti-seizure Meds

-Use this within 7 days of injury!!

-To DEC incidence of Post-Traumatic Seizures (PTS)

-Phenytoin

-Levetiracetam

-Uses an Opioid like Fentanyl FIRST, then:

-Use in conjunction w/ Sedative

(this is ideal for ppts w/ significant ICP elevation)

Analgesia-FIRST Sedation

Uses an Opioid infusion ALONE to achieve both sedation + manage pain

Analgesia-BASED Sedation

This is the preferred analgesic in TBI management due to greater efficacy

Fentanyl

This is the preferred sedating agent in TBI management

-DEC cerebral metabolic demand and ICP

-Short duration of action → allows for intermittent neurologic clinical assessment

Propofol

-Severe metabolic acidosis

-Rhabdomyolysis

-Hyperkalemia

-Kidney failure

-Cardiovasacular collapse

Propofol-infusion Syndrome (when used as longer duration/infusion)

May be necessary to treat Secondary damage

-Relieve pressure inside skull

-Remove hematomas (collection of blood outside blood vessels in brain)

-Remove debris or dead brain tissue

Surgery