Trauma & Head Injury

Question 1

What is the GCS?

Answer 1

Eye

4) Spontaneous
3) Speech
2) Pain
1) None

Verbal

5) Oriented
4) Confused
3) Inappropriate
2) Incomprehensible
1) None

Motor

6) Follows Commands
5) Localizes Pain (pulls on source of pain)
4) Withdraws to pain (just pulls away, does not go after pain source)
3) Decorticate Flexion
2) Decerebrate Extension
1) No response

Question 2

What are the GCS mild, mod, severe?

Answer 2

8 or less for 6+ hours is severe
9-12 is moderate
Mild is 13- 15

Question 3

How is C-Spine cleared?

Answer 3

1) no cervical pain or tenderness
2) no paresthesia or neurological deficits
3) normal mental status
4) no distracting pain
5) >4 years of age

if you can’t meet above then

• cross-table lateral c-spine film C1 - T1
• open mouth odontoid view, thoracolumbar, A/P and lateral plain views required

Once patient is stable enough to tolerate a CT, you can evaluate c-spine then

Question 4

How do you calculate CPP?

Answer 4

CPP = MAP - ICP

Question 5

What is ideal CPP for patient with TBI?

Answer 5

• if head injury ideal CCP is unknown
• (normal CPP is 70 - 85)
• early studies suggest 70 - 80
• new evidence that if CPP> 70 then ARDS
• Cerebral ischemia if CPP < 50 - 60
• somewhere in middle CPP 60 - 70 reasonable

Question 6

What MAP range allows cerebral autoregulation?

Answer 6

Cerebral autoregulation maintains CBF (cerebral blood flow) at constant rate with MAP between 60 - 150

Question 7

How can you decrease ICP?

Answer 7

• no venous obstruction with draining blood from brain (check C-collar)
• elevate head 15 - 30 deg
• mannitol (decreases by osmotically shifting blood from brain to AVC, decreases CSF production)
• lasix
• barbiturate (reduces ICP 2/2 cerebral vasoconstriction and CMRO2)
• hyperventilation ETCO2 25 - 30 (has risk of cerebral ischemia). Used as last resort bc patients in first 24hrs after brain injury already have reduced cerebral blood flow. After 1-2 days the bicarb levels in CSF adjust to compensate for PaCo2 change so no longer effective.

Question 8

How much does CMRO2 decrease per degree?

Answer 8

1 degree drops the CMRO2 by 7% (below 36)

Question 9

What are normal values for

• Cardiac Index
• PCWP
• PA pressure
• Mixed venous oxygen sat

Answer 9

• Cardiac Index = 2.6 - 4.2
• PCWP = 2 - 15 mmHg
• PA pressure = 15-30 / 4- 12 mmHg
• Mixed venous oxygen sat = 65 - 75%

Question 10

How do you treat fat embolism?

Answer 10

• 100% Oxygen
• treat hypotension
• correct hypovolemia
• replace blood and platelets
• c/w mechanical vent
• monitor, notify surgeon (may switch from IM nailing to external fixation of femur)

Question 11

What is pathophysiology of ARDS

Answer 11

pulm manifestation to SIRS 
injury to cap / alveolar membrane 
b/l diffuse infilatrates
severe dyspnea 
hypoxemia (2/2 intrapulm shunting)
ARDS can cause fibrosis alveolitis and permanent lung scarring

Question 12

What is the ARDS severity by the Berlin Definition?

Answer 12

PaO2 / FIO2

• 300 to 200 mild
• 200 to 100 mod
• under or equal to 100

Question 13

During the case the BP drops to 95/60 and PIP increases mid 40s, O2 sat drops to 80s. What’s differential

Answer 13

• ETT to R mail stem
• expanding tension PNX
• cardiac tamponade
• fat emboli 2/2 fractured femur
• allergic reaction
• aspiration pneumonitis (increased PVR 2/2 hypoxic pulm vasoconstriction causing low BP)

Question 14

Patient had TBI, on day 5 serum sodium is 129, high urine sodium. What’s the diagnosis?

Answer 14

High urine sodium and hyponatremia is consistent with cerebral salt wasting syndrome (CSWS) and SIADH

CSWS has hypovolemia, normal ADH, concentrates urine Na above 100

SIADH is euvolemic, high ADH, rare if urine Na is over 100

Question 15

MACE scoring system

Answer 15

Need 2 or more

• IDDM
• ischemic heart dz
• CAD h/o heart failure
• h/o CVD
• CKD
• Supra-inguinal vascular, intraperitonal or intrathoracic surgery