ABPN Neurocritical Care flashcards
ABPN Neurocritical Care · Build recall with a focused review session.
32 cards. Read the term and the definition here. The deck at the top of this page is optional.
- Cerebral perfusion pressure formula
- CPP equals mean arterial pressure minus intracranial pressure. Typical adult target is 60 to 70 mmHg to maintain adequate cerebral blood flow.
- Monro-Kellie doctrine
- The skull is a fixed volume containing brain, blood, and CSF. An expanding mass first displaces CSF and venous blood before intracranial pressure rises steeply.
- CO2 effect on CBF
- Cerebral blood flow changes about 3 to 4 percent per mmHg of PaCO2. Hyperventilation lowers PaCO2 and reduces flow, while hypoventilation raises it.
- ICP waveform P2 loss
- Loss of the normal P1 greater than P2 relationship and rising P2 amplitude indicate reduced intracranial compliance and impending herniation.
- Brain tissue oxygen threshold
- Normal PbtO2 is 23 to 35 mmHg. Values below 15 to 20 mmHg indicate risk of ischemic injury and prompt intervention.
- IV thrombolysis time window
- Alteplase 0.9 mg/kg (max 90 mg) is approved within 4.5 hours of ischemic stroke onset. Tenecteplase 0.25 mg/kg is an accepted alternative.
- Thrombectomy extended window
- Mechanical thrombectomy is indicated up to 24 hours in selected large vessel occlusion patients using DAWN or DEFUSE-3 imaging criteria.
- Post-thrombolysis blood pressure target
- After IV thrombolysis, keep blood pressure below 180/105 mmHg for 24 hours to reduce hemorrhagic transformation risk.
- Nimodipine in subarachnoid hemorrhage
- Nimodipine 60 mg orally every 4 hours for 21 days reduces delayed cerebral ischemia and poor outcome after aneurysmal subarachnoid hemorrhage.
- Vasospasm transcranial Doppler threshold
- Mean flow velocity above 120 cm/s in the middle cerebral artery suggests vasospasm. Peak risk is days 3 to 14 after subarachnoid hemorrhage.
- TBI secondary injury avoidance
- Avoid hypoxia with SpO2 below 90 percent and hypotension with systolic blood pressure below 100 to 110 mmHg, since each episode worsens outcome.
- Hyperosmolar therapy agents
- Mannitol 0.5 to 1 g/kg or hypertonic saline 3 percent bolus 150 to 250 mL can be used for elevated intracranial pressure.
- Post-traumatic seizure prophylaxis
- Phenytoin or levetiracetam for 7 days reduces early post-traumatic seizures but does not prevent late epilepsy.
- Spinal cord injury MAP target
- Maintain mean arterial pressure of 85 to 90 mmHg for 5 to 7 days after acute spinal cord injury to support cord perfusion.
- Neurogenic shock features
- Hypotension with bradycardia from loss of sympathetic tone after high spinal cord injury. Treat with vasopressors and atropine for bradycardia.
- Status epilepticus first-line
- Lorazepam 0.1 mg/kg IV (max 4 mg) is first-line, and may be repeated once before starting a second-line antiseizure medication.
- Second-line status epilepticus dosing
- Options include levetiracetam 60 mg/kg (max 4500 mg), fosphenytoin 20 PE/kg, or valproate 40 mg/kg after benzodiazepines.
- Refractory status epilepticus
- Continuous IV anesthetic such as midazolam, propofol, or pentobarbital titrated to EEG burst suppression after failure of first- and second-line therapy.
- Propofol infusion syndrome
- Metabolic acidosis, rhabdomyolysis, bradycardia, and cardiac failure with prolonged high-dose propofol infusion; stop the drug if suspected.
- GBS treatment options
- IVIG 0.4 g/kg/day for 5 days or plasma exchange is effective. Corticosteroids are not effective in Guillain-Barre syndrome.
- GBS respiratory failure criteria
- Intubate for vital capacity below 15 to 20 mL/kg, a declining trend, or bulbar dysfunction in Guillain-Barre syndrome.
- Myasthenic crisis treatment
- Plasma exchange or IVIG is first-line. Avoid aminoglycosides, magnesium, and quinolones, which can worsen weakness.
- Bacterial meningitis dexamethasone
- Dexamethasone 0.15 mg/kg every 6 hours given before or with the first antibiotic dose in adults with suspected pneumococcal meningitis.
- HSV encephalitis treatment
- IV acyclovir 10 mg/kg every 8 hours for 14 to 21 days. Do not delay treatment for CSF PCR results.
- Cerebral salt wasting
- Hypovolemia with high urine sodium and low serum sodium after neurosurgery. Treat with volume and salt replacement.
- SIADH after neurosurgery
- Euvolemia with concentrated urine and low serum sodium. Treat with fluid restriction.
- CSF leak confirmation
- Beta-2 transferrin in nasal fluid confirms a CSF leak. Avoid positive pressure and Valsalva maneuvers.
- Sodium correction limits
- Correct hypernatremia no faster than 10 to 12 mEq/L per day and hyponatremia no faster than 8 to 10 mEq/L per day.
- Apnea test criteria
- Disconnect the ventilator, deliver 100 percent oxygen, and confirm no respiratory effort with PaCO2 at least 60 mmHg or a 20 mmHg rise.
- SSEP N20 absence
- Bilateral absence of the N20 response on median nerve SSEP is a strong predictor of poor neurologic outcome after anoxic injury.
- Naloxone titration goal
- Naloxone reverses opioid-induced respiratory depression. Titrate to adequate respiratory effort rather than full arousal to avoid withdrawal.
- Serotonin syndrome features
- Clonus, hyperthermia, and autonomic instability from serotonergic drugs. Treat with cyproheptadine and supportive care.