Coma And Brain Stem Death Flashcards
Coma definition
Inability to obey commands, speak or open eyes to pain
GCS less than 8 is a generally accepted operational definition
Coma results from ?
Dysfunction of upper brain stem
Bilateral diencephalic dysfunction
Diffuse lesions in both cerebral hemispheres
Decorticate features
Abnormal flexion in upper extremities
Abnormal extension in lower extremities
Decorticate occurs due to
Disinhibition by removal of corticospjnal pathways above midbrain
(Not working above midbrain)
Decerbrate features
Abnormal extension in both upper and lower extremities
Usually occurs just before end of life
Aetiology for comas are usually
Metabolic
(Electrolyte, endocrine/diabetic/hypoglycaemia, vascular, toxic/drugs Nutritional (b12 deficiency)
Structural aetiology types
Vascular
Infectious
Trauma
Neoplasticism
Pseudocoma aetiologies
Lockedin syndrome (ventral pontine infarction)
Psychiatric (Catatonia)
Neuromuscular weakness (myasthenia gravis)
Approach to comatose patient
Found unresponsive -
- ABC- (Secure airway)
- Priority labs- ABG, serum electrolytes, glucose
- treat reversible or rapidly correctable causes
- priority investigations (scans/ CT)
- Detailed history/neurological examination
Brain death definition?
Person no longer has any brain stem functions and has permanently lost the potential for consciousness and capacity to breathe
Brain death criteria
Fixed pupils Absent corneal reflexes Absent oculovestibular reflex Absent oculocephalic reflex Absent gag and cough reflex
No response to deep central pain
Apnoea with arterial pC02>60 mmhg
Core temp>34
Brain death in children ?
Guide ca be used in kids I’ve 2 months
Under 2 months can’t be used, brain has plasticity and can recover from many things adults can’t
