Coma, Persistent Vegatative State, Brain Death Flashcards
Define coma
A state of unarousable psychological unresponsiveness in which individual shows no response to external stimulus
Which classification is used to define when someone is in a coma?
Glasgow coma scale
In which GSC rating would someone be considered to be in a coma?
GSC of 8 or less
What does consciousness depend on?
Intact ascending reticular activating system
Functioning cerebral cortex
What is the reticular activating system responsible for?
Arousal
Which part of consciousness are the cerebral hemispheres responsible for?
Awareness of environment
What are causes of a reduced conscious level?
Toxic/metabolic states
Seizures
Damage to reticular activating system
Raised ICP
List some toxic/metabolic states.
Hypoxia
Sepsis
Hypotension
Drug intoxication
Renal or liver failure
Hypoglycaemia
Ketoacidosis
If someone comes in with a low level of consciousness, what will the management be?
ACB approach
(airways, breathing, circulation)
Patterns of breathing may give an indication to what is causing the coma. If there is depressed respiration, what could be the cause?
Drug overdose
Metabolic disturbance
Patterns of breathing may give an indication to what is causing the coma. If there is increased respiration, what could be the cause?
Hypoxia, hypercapnia, acidosis
Hypercapnia= high levels of CO2 in blood
Patterns of breathing may give an indication to what is causing the coma. If there is fluctuating respiration, what could be the cause?
Brainstem lesion
In those with reduced conscious level, which condition should be considered and treated on suspicion?
Meningitis
Upon examination, if a patient has no meningism or focal brainstem/lateralising cerebral signs, what could be the cause of their coma?
Toxic cause
Metabolic cause
Systemic cause
Upon examination, if a patient has meningism but no focal brainstem/lateralising cerebral signs, what could be the cause of their coma?
Meningitis
Encephalitis
Subarachnoid haemorrhage
Upon examination, if a patient focal brainstem/lateralising cerebral signs and possibly meningtism, what could be the cause of their coma?
Focal cerebral issue e.g. tumour or infarct
If there are no focal signs or meningism, which investigations may be done to try and work out the toxic/metabolic/systemic cause of the coma?
Toxicology screen, including alcohol levels
Blood sugar and electrolytes
Asses hepatic and renal function
BP
Acid-base assessment and blood gas
Consider carbon monoxide poisoning
If there is someone in a coma without focal or lateralising signs but with meningism, which investigations may be done to make a diagnosis?
CT head
Lumbar puncture
-> as remember, with these symptoms, likely to be subarachnoid haemorrhage, meningitis or encephalitis
In those with focal brainstem or lateralising signs, you’d be more worried of cerebral tumour, haemorrhage, infarction or abscess. Therefore, which investigations would be done?
CT or MRI
What is ‘locked in’ syndrome?
Patient has total paralysis below level of third nerve nuclei.
What is observed in ‘locked in’ syndrome?
Patient is able to open, elevate and depress eyes and has no horizontal or voluntary eye movement
What care would be involved in looking after a patient in a coma?
Maintenance of vital functions
Care of skin and avoidance of pressure sores by moving patient
Attention to bowel and bladder function
Control of seizures
Prophylaxis of DVT, peptic ulceration
Which two things are those who re bed bound at higher risk of developing?
DVT
Peptic ulceration
In non-epileptic attacks, a patient can seem like their in a coma even though they are not.
In who are non-epileptic attacks are more likely to happen?
Young
Female more than male
Psychiatric history
List the clinical features of a non-epileptic attack.
Sinusoidal tremor
Pelvic thrusting
Side to side head movements
Eyes closed and resists opening
Partial responsiveness
Which scale can be used to clinically predict whether someone is having a stroke or not?
Rosier scale
-> scale >0 predicts stroke
What is hemicraniectomy and when is it used?
Decompressive surgery for severe cerebral swelling post-stroke
