Neurosurgery Flashcards
Review the initial management of SAH.
- BP control with something titratable (clevidipine or nicardipine) to less than 160 or 140 depending on guidelines
- Arterial line for BP control
- Control of coagulation (CBC for thrombocytopenia, PT/PTT)
- Head of bead to 30*
- Preventing Valsalva (antiemetics and cough control) to limit increases in BP and ICP
- Nimodipine in the first 24 hours to prevent vasospasm
Why does spinal cord injury cause hypotension and bradycardia?
The sympathetic nervous system arises at the spinal level all the way down to T6, whereas the parasympathetic nervous system primarily from the brainstem (like the vagus nerve). As such, spinal cord injury disrupts the SNS and causes unopposed PNS stimulation.
An elderly person falls and strikes their chin on a table. They now have UE weakness without LE weakness. What is the diagnosis?
Central cord syndrome
Hyperextension neck injuries (like falling and hitting your chin on something) can cause syringomyelia that preferentially affects the UE.
Impingement of the ______ nerve root causes weakness with plantarflexion and numbness of the lateral foot and ankle.
S1
The __________ is adhered to the inner surface of the skull.
dura mater
____-dural hematomas happen from bleeds of the middle meningeal artery.
Epi
______-dural hematomas happen from bleeds of the bridging veins.
Sub
The __________ cranial nerve can get damaged when the temporal lobe herniates.
III
What is the clinical presentation of uncal herniation?
Ipsilateral pupillary dilation without response to light and contralateral hemiparesis
Normal ICP is _______- mm Hg.
10
By the Monroe-Kellie doctrine, ICP rapidly increases after ____________.
venous blood and CSF have been pushed out of the brain
Cerebral perfusion pressure is equal to ________________.
MAP - ICP
Review GCS scoring.
Eyes: 4 possible (“four eyes”)
- 4: open spontaneous
- 3: open to command
- 2: open to pain
- 1: closed
Verbal: 5 possible
- 5: oriented
- 4: confused
- 3: inappropriate words
- 2: incomprehensible sounds
- 1: no verbal response
Motor: 6 possible
- 6: obeys commands
- 5: localizes pain
- 4: withdraws from pain
- 3: flexion with pain
- 2: extension with pain
- 1: no response
People with a GCS score of ____ or less are considered as having a severe brain injury.
8
9-12 are moderate and 13-15 mild.
If there are right/left or UE/LE differences in the GCS score, use the _________ one.
better one
Epidural hematomas typically happen in what region?
Temporoparietal
_____________ are prone to rapid progression and warrant consideration of repeat CTs.
Cerebral contusions
They can progress to cerebral hematomas with mass effect.
What are the five types of intracranial hematoma?
Epidural
Subdural
Subarachnoid
Intraparenchymal
Intraventricular
In a mild TBI, what factors warrant head CT?
- Vomiting (typically greater than two episodes)
- Signs of skull fracture on exam
- Signs of basilar skull fracture (otorrhea, rhinorrhea with CSF, Battle sign, raccoon eyes)
- Age > 65
- Anticoagulant use
- GCS < 15 at two hours from injury
- High mechanism of injury
- Pre-event amnesia
- Loss of consciousness
- Seizure
Review the management of severe TBI.
Respiratory:
- Maintain SpO2 > 98%
- Maintain PaCO2 32-38 mm Hg
Cardiovascular:
- Maintain SBP > 100 mm Hg for patients 50-69 yo and > 110 mm Hg for 15-49 and 70+
Neurologic:
- Use short-acting sedatives and paralytics when needed to avoid confounding the neurologic exam
- Give mannitol (0.25 - 1.0 mg/kg) or hypertonic saline 500 mL bolus
- Elevate head of bed
What are the four components of an emergent neurologic exam?
- Mental status
- Pupillary size and dilation
- Lateralizing signs (motor equal and symmetric)
- Signs of spinal cord injury (numbness and focal weakness)
Mannitol is contraindicated in ______________.
hypotensive patients
You can control scalp hemorrhage by _____________.
direct pressure
But be careful in using pressure if the skull feels unstable.
If you see partially exteriorized objects coming from the brain, then __________.
leave it in place
What are the neurologic criteria for brain death?
- GCS 3
- Non-reactive pupils
- Absent brainstem reflexes (corneal, gag, doll’s eyes)
- No spontaneous ventilation
- Absence of confounding factors such as hypothermia and alcohol intoxication
Aggressive hyperventilation leads to cerebral vaso-_________.
constriction
This is beneficial for decreasing edema but detrimental to maintaining CPP.
______________ syndromes present with disproportionate loss of UE motor sensation compared to LE.
Central cord
Burst fractures happen from what type of force?
Axial compression
___________ fractures occur from flexion of the thoracic spine, often from an improperly placed lap belt.
Chance
Axial loading with flexion causes ______________.
anterior wedge compression fractures
Patients with _____________ fractures are vulnerable to secondary injury with rolling.
thoracolumbar junction fractures
What types of spinal injury warrant further workup for carotid/vertebral artery injury?
C1-C3 fracture
Cervical spine fracture with subluxation
Fractures of the foramen transversarium
Patients with normal neck radiographs and neck pain should be considered for ___________ to rule out occult injury.
MRI or flexion-extension x-rays