Lecture 28 - Coma and Herniation

Question 1

Coma implies dysfunction of the Ascending ______ ______ System

OR

both _____-______.

Anatomically, this includes the Central _______ structures (bilaterally) from caudal medulla to rostral midbrain

OR

Both hemispheres

Answer 1

Ascending Reticular Activating System

Hemi-cortices

Brainstem structures

Question 2

The degree of coma may not have prognostic value, but the cause of the coma may. That is, _______ coma and hypoxic injury likely have WORSE prognosis than ______ coma.

Answer 2

Structural and Hypoxic injury

Metabolic

Question 3

Focal signs in Coma mean the deficit is _______ (localized or diffuse?)

Answer 3

Localized

Question 4

Testing ______ in coma patients help to determine which areas of the brain are and are not functioning.

Answer 4

Reflexes

Question 5

If coma patients do no have purposeful responses to painful stimuli, which area of the brain is non-functional? What is the term for this type of coma?

Answer 5

The cerebral cortex is not working.

“Decorticate”

Question 6

Describe how the following pupil presentations indicate the respective regions of the brain responsible for coma:

Pinpoint –>

Small and Reactive –>

One dilated and both fixed –>

Mid-position and Fixed –>

Large and Fixed –>

Answer 6

Pinpoint –> Suspect Opioid poisoning!
or Pontine

Small and Reactive –> Metabolic or Diencephalon

One dilated and both fixed –> CN III involvement (Emergency!)

Mid-position and fixed –> Midbrain

Large and Fixed –> Tectal or Atropine eye drops (Widely dilated)

Question 7

In a comatose patient, ______ (present or absent?) Doll’s eye reflex is indicative of a deeper coma.

Answer 7

Absent

It is normally absent in non-comatose people, but its absence in comatose patients suggests no Pontine function.