21: ABI Flashcards
Definition
An injury to the brain that results in deterioration of cognitive, physical, emotional or independent functions, Can be temporary or permanent.
Any brain injury that occurs after birth.
Umbrella term for: Traumatic brain injury, stroke, brain tumour, hypoxia, infections, alcohol and substance misuse.
Difference between ABI and TBI
TBI: Subset of ABI, caused by blow too the head or missile intruding into the head, caused by head being moved rapidly (shaken baby syndrome, car crash), brain tissue can be damaged.
ABI: Some considered non-traumatic. Cells and tissues are damaged by toxic substances, lack of oxygen, pressure, direct infection or stroke.
Aetiology
Sporting injuries, car accidents, assault and war injuries, near drownings, infections, medical mishap, bungee jumping.
Most: Motor vehicle, low fall, pedestrian.
Epidemiology
Kids 0-24 because of risky behaviour, higher in males
Closed head injury
Most common. Due to: Brain moving inside skull.
Results in: Diffuse brain injury
Signs: Focal lesions, bruising, coup and countercoup injuries
What is shaken baby syndrome
Retinal haemorrhaging, brain swelling, subdural haematoma. Brain moves about inside skull, widespread damage through sheering and twisting and rotating of nerves, blood vessels and tissue. Forward rotational movement of brain on fixed brain stem gives rise to loss of consciousness and coma
Coup and countercoup injuries
Head gets flung to the right side, brain smacks into left side of skull. Type and extent of damaged relates to speed and direction of head movements. Airbags and head rests have gone forward to help.
Symptomology
Dependent on: Severity of lesion, length of time before diagnosis (primary and secondary injury effects), structural areas of brain affected.
What happens in the brain:
Cerebral oedema: Swelling which causes: Raised intracranial pressure, structures can’t function which affects homeostasis etc., cerebral ischaemia (restricted blood supply), cerebral herniation (pushes down on foramen magnum (herniation) causing hypotension, loss of connectivity and sensory control, homeostasis etc.
Signs and symptoms
Mild to moderate: Conscious state, eyes open, can say a few words, make motor responses, some pain react to reflexes.
Severe: Comatose condition: Eyes aren’t open, no responses
Medical investigations
The earlier, the better, as much accuracy as possible.
Physical examination, X-ray, CT, MRI, neurological examinations:
Glasgow coma scale, PTA (post traumatic amnesia test), testing reflexes (tendon, pupillary, babinski), mental state exams, sensory and motor tests, lumbar puncture.
What you do depends on level of consciousness.
Treatment
Intubation and respiration, possibly tracheostomy (machine to help breathe), IV to prevent shock, stop bleeding, craniotomy (hole to get blood out), catheterisation, close and constant neurological nursing care.
Medications: Antibiotics, pain killers, anti-seizure medications
Prognosis
Glasgow coma scale: 3-9 after resuscitation. Hypotension at admission, fixed and dilated pupils on admission, CT showing oedema and ventricular occlusion.
