Neurosurgery Trauma II

Heterogeneous with mixed areas of high and low densityQ

• Cushing reflex classically presents as an increase in systolic blood pressure, reduction of the heart rate (bradycardia), and irregular respirationQ.
• It is caused by increased intracranial pressureQ.

7th or 8th nerve palsiesQ

A delayed craniotomyQ and anterior fossa dural repair is occasionally requiredQ to prevent meningitis

• HypoxiaQ: PO2 <8 kPa
• HypotensionQ: SBP< 90 mmHg
• Raised ICPQ: ICP >20 mmHg
• Low cerebral perfusion pressureQ: CPP <65 mmHg
• HypercapniaQ
• Pyrexia (hyperthermia)Q
• SeizuresQ
• Metabolic disturbance (HypergycemiaQ)

• Early: ipsilateral dilated pupils, signs of supratentorial mass lesionQ
• – Late: Ipsilateral hemiplegia, progressive ptosis and 3rd nerve palsy, Cheyne-stokes respirationQ
• – Very late: Quadriparesis, bilateral fixed and dilated pupils, erratic respiration and death

Ipsilateral 3rd nerve, contralateral brainstem (later) and whole brainstem (eventually) occursQ

• – Early: Erratic respiration, small reactive pupils, increased limb tone and bilateral extensor plantarQ
• – Late: Cheyne-stokes respiration, decorticate rigidityQ
• – Very late: fixed and dilated pupils, decerebrate posturing

Upper midbrain (first), pons (later) and medulla (finally)Q

It is a situation in which a non-painful stimulus, once perceived, is experienced as painful, even excruciating

Severe pain in response to a mildly noxious stimulus

Presence of widespread axonal damage (white matter) in both hemispheres secondary to severe head injuryQ

Lobar white matter at the junction of grey and white matterQ >Corpus callosum >Brain stemPathology

MRI (better than CT scan)

ICP <20 mmHg and CPP 60 mmHgQ

• −−Drain CSF via ventriculostomyQ (if in place)
• −−Elevate head of the bedQ; midline head position
• −−Osmotherapy—mannitolQ 25–100 g q4h as needed (maintain serum osmolality <320Q mosmol) or hypertonic salineQ (30 mL, 23.4% NaCl bolus)
• −−Glucocorticoids—dexamethasone 4 mg q6h for vasogenic edema from tumor, abscessQ (avoid glucocorticoids in head trauma, ischemic and hemorrhagic strokeQ)
• −−SedationQ (e.g., morphine, propofol, or midazolam); add neuromuscular paralysis if necessary (patient will require endotracheal intubation and mechanical ventilation at this point, if not before)
• −−HyperventilationQ—to PaCO2 30–35 mmHg
• −−Pressor therapyQ—phenylephrine, dopamine, or norepinephrine to maintain adequate MAP to ensure CPP 60 mmHg (maintain euvolemia to minimize deleterious systemic effects of pressors)

• a. High-dose barbiturate therapy (“pentobarb coma”)Q
• b. Aggressive hyperventilation to PaCO2 <30 mmHgQ
• c. HypothermiaQ
• d. HemicraniectomyQ

• 1. GCS < 13 at any point
• 2. GCS 13 or 14 at 2 hours
• 3. Focal neurological deficit
• 4. Suspected open, depressed or basal skull fracture
• 5. Seizures
• 6. Vomiting > one episode

• Motor responseQ
• Patients scoring 3 or 4 have an 85% chance of dying or remaining vegetative, while scores above 11 indicate only a 5-10% likelihood of death

• Otitis media, mastoiditis - Temporal lobeQ >Cerebellum
• Paranasal sinusitis, dental infections - Frontal lobesQ
• Hematogenous - Parietal lobeQ

• • Surgical drainage + IV antibiotics for at least 6 weeksQ.
• • Multiple small abscesses may be treated medically with antibiotics targeted against organisms
• • Steroids are reserved for cases with significant edema or mass effectQ