Approach To Unconscious Patient

Question 0

Causes of unconsciousness

Answer 0

1. Vasovagal attack- syncope
   Usually in young females,preceded by standing for a long time. There is a warning feeling of dizziness, visual blurring, sweating and paleness. Lasts 2 minutes max and patient is fine in 15 minutes.

Question 1

What is the Reticular Activating System.

Answer 1

System which fires at a particular frequency for conscious and unconsciousness. If brain hemispheres swell interfering with firing of RAS (via compression of brain stem) rendering patient unconscious.

Question 2

Causes of unconsciousness (2)

Answer 2

2. Postural hypotension
   Usually in middle aged, elderly on meds for HPT, or side effect of drug for postural hypotension. Warning sign is dizziness when standing up. There is usually a difference of 30mmHg in blood pressure when lying down and standing up.

Question 3

Causes of unconsciousness (3)

Answer 3

3. Hyperventilation
   Usually is young females, preceeded by anxiety, subjective feeling of gasping for air.
   Vasoconstriction of bvs in base of brain (circle of Willis) due to low CO2.
   Rx- brown paper bag

Question 4

Causes of unconsciousness(4)

Answer 4

4. Cardiac arrthymia
   Usually meddle aged and elderly. Not related to posture. History of ischemic heart disease. Patient experienced palpitations, marked colour change and irregular pulse before falling.

Question 5

Causes of unconsciousness(5)

Answer 5

5. Hypoxia-rare
6. Hypoglycemia- more common. Overwhelming feeling of hunger before unconsciousness, preceded by psychotic and drunk like behaviour (staggering, slurred speech, saying ridiculous things). Patient experiences overdrive effects of adrenalin- palpitations, tremor,

Question 6

Causes of unconsciousness (6)

Answer 6

6. Severe localized brain stem lesion (at circle of Willis). Called a vertebro/basilar transient ischemic attack. Common in middle aged or elderly in known arteriopathic- history of MI, angina, intimittent claudication, stroke.
   Rx- blood thinners eg aspirin, warfarin to prevent thrombosis.

Question 7

Causes of coma

Answer 7

Medical emergency- patient cannot be aroused
A-apoplexy- bleeding into an organ ie intracranial bleed.
E-epilepsy- status epilepticus/ post ictal coma
I-infection or injury- cerebral abscess, meningio-encephalitis.
O-opiates
U-uraemia- metabolite disturbance.

Question 8

What is the sleep wake cycle.

Answer 8

Times when eyes are open during a coma and when eyes are closed but it doesn’t mean brain will recover.

Question 9

What is the locked in syndrome.

Answer 9

Fully conscious but unable to move a muscle except upper eyelid of eye.