neurological

glasgow coma score - 3 components

1. eye opening (4)

2. verbal response (5)

3. motor response (6)

3 (teddy bear) -15 (normal)

glasgow coma score - eye opening

1 - none

2 - to pain

3 - to speech

4 - spontaneous

glasgow coma score - verbal response

1 - none

2 - incomprehensible

3 - inappropriate words

4 - confused

5 - oriented

glasgow coma score - motor response

1 - none

2 - extension (decerebrate)

3 - flexion (decorticate)

4 - withdraws

5 - localizes

6 - obeys commands

GCS interpretations

“LESS THAN 8” - INTUBATE!

intubated patients - scores range from 2T-10T (verbal response is NOT accounted for)

indicates severe brain injury or unresponsiveness with immediate concern for airway protection

monroe-kellie doctrine

principle of intracranial hemodynamics that the combined volume of brain, blood, and CST is constant

normal state (ICP normal)

brain is a “box” of incompressible space

volume inside the cranium (“box”) is fixed

compensated (ICP normal)

intracranial components can initially compensate for extra volume while the ICP remains normal

CSF and venous blood can be compressed, providing a degree of pressure buffering

decompensated state (ICP high)

limit of displacement of CSF & blood has been reached

volume of mass reaches critical threshold (rapid increase in ICP) → can lead to reduction or cessation of cerebral blood flow & herniation risk

volume-pressure curve

when the ICP increases beyond pressure limit, herniation can occur

medical therapies for brain injury

primary goal: prevent secondary damage to an already injured brain

• hypertonic saline

• reverse anticoagulation

• mannitol (osmitrol)

• IV fluids/blood products

TBI - hypertonic saline

• creates an osmotic shift of fluid, used to decrease ICP

• concentrations of 3% to 23.4% commonly used

  • 23.4% is for physician administration

• preferred agent for hypotensive patients with elevated ICPS (not a diuretic)

• close monitoring of serum osmolarity + sodium necessary

mannitol (osmitrol)

• a potent osmotic diuretic, used to decrease ICP

• fluid shifts from brain tissue into intravascular space, facilitating reduction in ICP

• use with caution in hypotensive patients

• results in free water clearance & increased serum osmolality

IV fluids/blood products

• hypovolemia in TBI patients is harmful!

• avoid hypotension (think: MAP - ICP = CPP)

  • avoid hypotonic solutions → worsens cerebral edema

• carefully monitor serum sodium levels

reverse anticoagulation - medications

• antiplatelets (e.g. aspirin) → platelets

• [INR] coumadin (warfarin) → FFP, vit K

• [PTT] heparin, lovenox → protamine sulfate