BLUNT HEAD INJURIES
Written by Rhiana Devadasan
Blunt head injuries = when a moving head strikes a fixed object, or vice versa, a moving object strikes an immobile head.
Can results in: scalp injury, skull fracture, brain contusion.
The injuries result from rapid deceleration of the head causing the brain to move within the cranial cavity and to come into contact with bony protuberances within the skull.
Etiology (causes)
- Road traffic accidents
- Falling from a height
- Occupational accidents
- Sports trauma
- Assault
Classification of Head Injuries
Depending on the damage of skin and soft tissues covering the skull:
- Opened - when there is a skin wound & skull coverings have opened up.
← Irrelevant when we're talking about blunt head injuries.
- a) Penetrating - dura mater is damaged
- b) Non-penetrating - dura mater is spared
- 2) Closed - when there is injury to the head but the skin & soft tissues have remained intact.
(e.g. hematomas)
- a) Cerebral concussion (commotio cerebri) - mild head injury
- b) Cerebral contusion (contusio cerebri) - mild, moderate, severe
- c) Cerebral compression (compressio cerebri) - epidural hematoma, subdural hematoma, intracerebral hematoma, subdural hydroma
Based on, morphologically speaking, the type of injury:
- TYPE OF HEAD INJURY
- Skull fractures
- Vault
- Open vs closed
- Linear vs. comminuted
- Depressed or non-depressed
- Skull base fractures (may or may not be associated w/ CSF rhiorrhoea, otorrhoea, cranial nerve palsy)
- Intracranial Hematomas
- Extra dural
- Subdural (acute/chronic)
- Subarachnoid
- Intracerebral
ALL THESE ARE TYPES OF COMPRESSIO CEREBRI (cerebral compression)
Treatment
Surgery: aims at removing intracranial hematomas & foreign bodies. Otherwise....
Medical treatment: indicated to prevent infection & alleviate brain edema.
Pathophysiology of TBI (traumatic brain injury)
- Cerebral BF fluctuate & hypotension is common
- Intracranial presssure can increase & brain herniation can occur
- Primary Brain Injury = occurs at the time of impact (e.g. brainstem & hemispheric contusions, diffuse axonal injury, cortical lacerations)
- Secondary Brain Injury = some time after moment of impact & is preventable. Occurs as a result of hypoxia, hypotension, ↑intracranial pressure, ↓cerebral perfusion pressure, pyrexia (↑T) & metabolic disturbances.
MEASURING SEVERITY OF HEAD INJURIES
Glasgow Coma Scale (GCS)
← The total score is then added up at the end. The better the response, the higher the total score.