AMS & Coma

Question 1

How should AMS be described?

Answer 1

By what they are able to do, not by terms like ‘stuporous’ or ‘lethargic’.

Use AAOx4, counting backward from 10, serial 3’s, ability to remember 3 unrelated objects (tree, sandwich, bicycle)

Question 2

What is responsible for mental alertness?

What causes coma?

Answer 2

Mental alertness is maintained by cerebral hemispheres + reticular activating system of the brainstem.

Coma is due to diffuse disease of both cerebral hemispheres (usually metabolic) or a problem with the reticular activating system (disease that damages it, or CNS lesion the compresses it).

Question 3

For what % of coma is a structural lesion compressing the brain stem to blame?

Answer 3

Less than 20%

Question 4

Causes of Coma and AMS

Answer 4

A - alcohol, other drugs 
E - epilepsy, electrolytes, encephalopathy 
I - insulin 
O - opioids, oxygen 
U - uremia 

T- trauma, temp
I - infection (systemic or CNS)
P - psych
S - stroke, SAH, space occupying lesion, shock

Question 5

Important Hx in a AMS or coma pt?

Answer 5

1. Onset of Symptoms (acute vs gradual)
2. Recent Neuro Symptoms (HA, focal weakness, seizure)
3. Drug/Alcohol Use
4. Psych Problems
5. Recent Trauma
6. PMHx (Neuro disorder, DM, Renal/Liver Failure, Cancer)

Question 6

Physical exam for AMS or Coma?

Goal?

Answer 6

Goal: Differentiate structural focal CNS problem from diffuse metabolic problem.

1. Vitals
2. General Appearance - signs of trauma, symmetry of spontaneous movement
3. Mental Status - AAOx4, backward from 10, serial 3’s, 3 objects (tree, sandwich, bicycle)
4. Eye Exam
5. Motor Exam - symmetry of muscle tone/strength, DTRs

Question 7

How do I evaluate pt’s mental status?

Answer 7

1. AAOx4
2. Count Back from 10 (if successful, serial 3’s)
3. Recall 3 objects (tree, sandwich, bicycle)

Question 8

What is the GCS? How is it scored?

Answer 8

LOC assessment for Trauma pts.

1. 4-Eyes
   - 4 spontaneous
   - 3 to verbal
   - 2 to pain
   - 1 no response
2. Jackson 5
   - 5 oriented/converses
   - 4 confused conversation
   - 3 inappropriate words
   - 2 incomprehensible sounds
   - 1 none
3. 6 - Pick Up Sticks
   - 6 obeys
   - 5 localizes pain
   - 4 withdrawals from pain
   - 3 decorticate
   - 2 decerebrate
   - 1 none

Question 9

Significance of Temp in comatose pts?

Answer 9

Need Core Temp!! (rectal)

1. Hyperthermia
   - meningitis
   - sepsis
   - heat stroke
   - hyperthyroid
2. Hypothermia
   - environmental exposure
   - hypoglycemia
   - addisonian crisis (rare)

Question 10

Significance of placing AMS or coma pts on a cardiac monitor?

Answer 10

Bradycardia or arrhythmia may alter cerebral perfusion and cause AMS.

Question 11

Significance of respiratory rate in AMS or coma?

Answer 11

Tachypnea - may be compensation for hypoxemia or metabolic acidosis

Slow Resp may need BVM assist.

Question 12

Significance of BP in AMS/coma pts?

Answer 12

Hypotension

1. Hypovolemia
2. Sepsis
3. Neurogenic Shock

Hypertension

1. Increased ICP
2. Uncontrolled HTN -> encephalopathy & coma

Question 13

Cushing’s Reflex?

Answer 13

Increased BP and decreased pulse in response to Increased ICP.

Question 14

Difference between decorticate and decerebrate posturing?

Answer 14

Decorticate - flexion of arms/extension of legs, indicates damage to descending motor pathways above the central midbrain

Decerebrate - extension of arms and legs, indicates damage to midbrain and upper pons. (BAD)

Question 15

What is a coma?

Answer 15

Depressed mental state in which verbal and physical stimuli cannot elicit useful response.