ICS-Coma, Brain Death & Herniation

Question 1

A woman had a head injury while skiing. She hit her head and was unconscious for a few minutes, was examined and then released. Shortly thereafter she had a headache, double vision when looking right and lost conscious a few minutes later. Her brain CT is shown below. What is your diagnosis?

Answer 1

Encephalopathy. Note that her symptoms are quite focal and fast. CT reveals a hematoma that pushes the brain over and obstructs the IVF. This causes a non-communicating (obstructive) hydrocephalus to occur.

Question 2

What are the primary causes of encephalopathy?

Answer 2

Infarction, hemorrhage, tumors, infections and CSF obstruction.

Question 3

What are the secondary causes of encephalopathy?

Answer 3

Local edema (vasogenic or cytotoxic) and increase intracranial pressure.

Question 4

What are tragic outcomes that result from encephalopathy?

Answer 4

Anoxic encephalopathy, herniation, brain death.

Question 5

How do you score the GCS?

Answer 5

*

Question 6

What is the GCS necessary to classify neurological symptoms as spells?

Answer 6

GCS can be no less than 15. Otherwise there is evidence of cortical failure.

Question 7

How do you assess cranial nerves in a comatose patient?

Answer 7

Pupils (size, equal, reactive to light), corneal reflex, doll’s eyes (eyes locked in one location).

Question 8

How do you assess motor and sensory function in a comatose patient?

Answer 8

Pain withdraw and watching for spontaneous movements.

Question 9

How do you assess reflexes in a comatose patient?

Answer 9

Look for asymmetrical and abnormal reflexes.

Question 10

You have a patient who presented with focal neurological deficits prior to becoming comatose. What are likely etiologies?

Answer 10

Stroke, tumors and cerebral edema.

Question 11

You have a patient who became comatose without any focal neurological signs. What are likely etiologies?

Answer 11

Prolonged hypoxia (MI, ICP), drugs (benzos & barbiturates) and metabolic disorders.

Question 12

When does this occur? How do you differentiate it from other diseases?

Answer 12

This is papilledema that occurs when the pressure in the head exceeds the pressure in the eye. You differentiate this from optic neuritis (especially in MS patients) because optic neuritis will cause unilateral vision loss. Where papilledema has no vision loss and signs will be bilateral.

Question 13

A 28 year old man was found unconscious. His GCS is 9. He is able to move his right side in response to pain but not his left. Physical exam reveals a + left Babinski. What are you thinking as far as a diagnosis?

Answer 13

Intracerebral hematoma. It’s not drug overdose because of the Babinski.

Question 14

How do you calculate cerebral perfusion pressure?

Answer 14

1/3(Systolic) + 2/3(Diastolic) - Intracranial pressure.

Question 15

At what blood pressure does your brain become anoxic?

Answer 15

60mmHg.

Question 16

What is a normal intracranial pressure in the lateral decubitus position?

Answer 16

130-180 mmH2O (10-15mmHg)

Question 17

A patient comes to the ED after slamming his head into a tree while snowboarding. Vital signs are BP 180/110, HR 45 and RR 10. Considering the patient hit his head, what is causing his vitals to present this way?

Answer 17

Cushing reaction (the triad of hypertension, bradycardia and respiratory depression). This is caused by increased intracranial pressure from hemorrhage that constricts arterioles. Constricted arterioles causes cerebral ischemia, which elicits sympathetic reflex to increase perfusion pressure (hypertension). This then increases carotid stretch which stimulates the parasympathetic system to induce bradycardia.

Question 18

Characterize the pathology in these images.

Answer 18

Laminar necrosis. Note the very small and thin layer of cortex that exists as a result of increased ICP.

Question 19

A 42 year old man is in the ICU. His blood pressure is 180/120 and his intracranial pressure is 50mmHg. Calculate his cerebral perfusion pressure.

Answer 19

1/3(180) + 2/3(120) - 50 = 90mmHg

Question 20

What type of herniation do you most often see in clinic? How will these present?

Answer 20

C) Tentorial herniation of the temporal lobe. A is a herniation through the falx cerebri. B is a tonsillar herniation through the foramen magnum. Tentorial herniations will present with a blown pupil and contralateral motor deficits. One thing to remember though is that the herniation can cause pressure on the opposite side of the brainstem and motor symptoms will be ipsilateral to the herniation.

Question 21

Name the 5 hemorrhages seen in this patient:

Answer 21

1) Subgaleal 2) Epidural 3) Subdural 4) Arachnoid 5) Intracranial

Question 22

What type of hemorrhage is seen below?

Answer 22

Duret hemorrhage. This is destruction of the reticular formation.

Question 23

Encephalitis vs. Cerebritis?

Answer 23

Encephalitis = viral (herpes, arboviruses, JC virus, coxsackie, echo, influenza). Cerebritis = bacterial (meningococcus, pneumococcus & tuberculosis)

Question 24

Normal levels for protein, glucose, granulocytes & lymphocytes?

Answer 24

Granulocytes: 0. Lymphocytes < 5. Protein < 50. Glucose > 50.

Question 25

What does an elevated CSF protein tell you?

Answer 25

BBB has been breached by a tumor, hemorrhage or infection.

Question 26

What are the main causes of the condition seen below?

Answer 26

This is a subarachnoid hemorrhage, most often caused by berry aneurisms.

Question 27

What causes of coma can be reversed to end the coma?

Answer 27

Drugs, metabolic disorders, brain swelling and some tumors.

Question 28

What are the five outcomes of coma?

Answer 28

Complete recovery, recovery with minimal impairment, minimal conscious state (determined by fMRI), persistent vegetative state (no evidence of cognition) and brain death (no brain stem reflexes & requires life support)