Neuroscience Clerkship

 
 

PRIMARY VS SECONDARY INSULTS IN TRAUMATIC BRAIN INJURY

Insults resulting from traumatic brain injury (TBI) are commonly divided into primary and secondary etiologies.

Primary

This is the precipitating injury that results in immediate effects. These include:

• Direct trauma to the brain

• Subarachnoid hemorrhage

• Epidural hematoma

• Subdural hematoma

• Contusion

• Axonal shear injury from accelerating/decelerating

Secondary

These are the systemic and intracranial effects that follow the initial injury. Survival of severe brain injury is dependent on avoiding or minimizing the secondary insults to the brain.

Systemic effects include:

• Hypotension/hypertension

• Hypoxia

• Anemia

• CO2 changes

• Electrolyte/glucose/acid-base abnormalities

Intracranial effects include:

• Ischemia

• Edema

• Hydrocephalus

• Infection

• Seizure

• Hemorrhage