Neurological Assessment of Critically Ill

Question 1

What are the different features that are assessed to define delirium?

Answer 1

• Feature 1: Acute change or fluctuating mental status*
• Feature 2: Inattention*
• Feature 3: Altered LOC or Feature 4: Disorganized thinking*

Question 2

List five specific causes of delirium.

Answer 2

TOXIC and DELERIOUS are the pneumonics

• CHF, shock, dehydration, meds (tight titration), new organ failure (kidney, liver), hypoxemia, infection/sepsis, immobiliziation, lack of other non-pharm (glasses, hearing aids, sleep protocols, noise), electrolyte problems (K+ especially)
• Drugs, labs (BUN/Cr), environmental factors, labs, infection, respiratory status, immobility, organ failure, unrecognized dementia, shock (sepsis, cardiogenic, steroid use

Question 3

Outline the components of the ABCDE protocol. Why is it important for an RT to be aware of this?

Answer 3

ABC-Awakening and Breathing Coordination…structured approach to SATs and SBTs

D-Delirium management/Nonpharm interventions

E-Early exercise and mobility

Timing of SATs and SBTs needs to be coordinated amongst RN and RT. RTs can help with non-pharm (orientating the patient, introduce, honour day/night, oral care etc). And RTs may manage airway in the early exercise—coordination required.

Question 4

Your patient’s ICP has been trending at 22 mmHg. Their BP is 115/75 mmHg. What is their CPP? Is this adequate?

Answer 4

ICP is slightly elevated (HTN defined as > 20).

Given BP the MAP is (115+75+75)/3=88.3 mmHg. CPP = MAP – ICP = 88.3 – 22= 66 mmHg.

Sources don’t pin down ideal CPP but goals clinically are to typically keep > 60-70 mmHg

Question 5

Licox

Does it Measure PO2 or SjO2

Answer 5

PO2

Question 6

Cerebral Oximetry

Does it Measure PO2 or SjO2

Answer 6

SO2

Question 7

Jugular Venous Saturation

Does it Measure PO2 or SjO2

Answer 7

SjvO2

Through the blood sample/spot check could give PO2 as well

Question 8

Licox

Localized area of general/global

Answer 8

PO2 of underlying tissue

Question 9

Cerebral Oximetry

Localized area of general/global

Answer 9

SO2 of underlying tissue

Question 10

Cerebral Oximetry

Localized area of general/global

Answer 10

SO2 of underlying tissue

Question 11

Jugular Venous Saturation

Localized area of general/global

Answer 11

Global approximation

Question 12

Cerebral Oximetry

Continuous or Spot Check

Answer 12

BOTH

Question 13

Licox

Continuous or Spot Check

Answer 13

Continuous

Question 14

Jugular Venous Saturation

Continuous or Spot Check

Answer 14

BOTH

Drawing sample and analyzing vs. continuous in vivo monitoring

Question 15

What type of ICP monitor allows for concurrent EVD?

Answer 15

Fluid-filled system where catheter is inserted into the brain ventricle.

Question 16

Oral and tracheal suction assesses which of the cranial nerves? What type of reflex is assessed when doing this?

Answer 16

IX-glossopharyngeal (sensory for the gag) *also innervates the carotid sinus

X-vagus (motor for gag, sensory for cough—laryngeal nerve; a branch of the vagus…and glottis closure is due to vagal innervation (Note phrenic nerve/spinal nerve for the diaphragm contraction part of the cough))

Question 17

A decreased PaCO2 level has what impact on cerebral blood flow?

Answer 17

Decreased CO2 levels in the brain causes vasoconstriction; this decreases cerebral blood flow

Question 18

List the complications/disadvantages of over-sedating patients in the ICU.

Answer 18

• Prolonged mech. ventilation and length of ICU stay
  
  • Tracheostomy
  • DVT, VAP
• Additional testing
• Added cost
• Inability to communicate
• Cannot evaluate for delirium

Question 19

Define delirium.

Answer 19

An acute brain dysfunction (not chronic, like dementia) that involves altered LOC and inattention or disorganized thinking. Tends to fluctuate through the day.

Question 20

Why is evaluating for delirium important in our critically ill patients?

Answer 20

• B/C it points to an underlying medical problem (infection/sepsis, organ failure, electrolyte problems, acid-base imbalance, need for non-pharmacological interventions).*
• Helps us optimize sedation and improve the patient care*

Question 21

Differentiate between the CNS and PNS.

Answer 21

• CNS-brain and spinal cord (*brain = cerebrum + cerebellum + brainstem)*
• PNS-12 pairs of cranial nerves (most originate in brainstem), 31 pairs spinal nerves*

Question 22

Which cranial nerves are significant for RTs? How do we test for their functionality?

Answer 22

• IX-glossopharyngeal (sensory for the gag) *also innervates the carotid sinus*
• X-Vagus (motor for the gag, also cough reflex) *stimulation can result in a brady!*

Question 23

Where in the brain does the control of respiration reside?

Answer 23

• In the brainstem:*
• Medulla (dorsal and ventral groups, primary control)*
• Pons (apneustic and pneumotaxic center that fine tunes the main controls)*
• NOTE: there is also the chemical control of respiration*
• Central and peripheral chemoreceptors*

Question 24

Where does the phrenic nerve arise from?

Answer 24

C3 to C5 (branches at each level)

Question 25

Describe how CO2 impacts cerebral blood flow.

Answer 25

Increased CO2 levels in the brain causes vasodilation; this increases cerebral blood flow

Question 26

What three categories does the GCS assess?

Answer 26

Motor/verbal and eye opening responses