CNRN Neuroscience Registered Nurse Certification 2 — Questions and Answers
Question 1: A patient with a subarachnoid hemorrhage suddenly develops severe vasospasm on day 4. Which medication is the first-line prophylactic agent?
- Nimodipine (Correct answer)
- Nicardipine
- Labetalol
- Mannitol
Correct answer: Nimodipine
Nimodipine (oral calcium channel blocker) is the standard prophylactic agent for cerebral vasospasm after subarachnoid hemorrhage, given for 21 days.
Question 2: When monitoring intracranial pressure (ICP), which waveform component indicates reduced cerebral compliance?
- Elevated P2 wave exceeding P1 (Correct answer)
- Prominent P1 percussion wave
- Low-amplitude P3 wave
- Flat baseline between waveforms
Correct answer: Elevated P2 wave exceeding P1
An elevated P2 (tidal) wave that exceeds P1 (percussion) indicates reduced intracranial compliance and impending ICP crisis.
Question 3: A patient post-craniotomy reports sudden-onset severe headache and vomiting 6 hours after surgery. The nurse's priority action is to:
- Notify the neurosurgeon immediately (Correct answer)
- Administer prescribed PRN antiemetic
- Reposition to 30-degree HOB elevation
- Obtain a STAT non-contrast CT head
Correct answer: Notify the neurosurgeon immediately
Sudden severe headache and vomiting post-craniotomy suggest intracranial hemorrhage; immediate neurosurgeon notification precedes any other intervention.
Question 4: Which finding on a lumbar puncture (LP) is most consistent with bacterial meningitis?
- CSF glucose <40 mg/dL with elevated protein and cloudy appearance (Correct answer)
- Clear CSF with normal glucose and mildly elevated protein
- Xanthochromic CSF with elevated RBCs
- CSF glucose >60 mg/dL with lymphocytic pleocytosis
Correct answer: CSF glucose <40 mg/dL with elevated protein and cloudy appearance
Bacterial meningitis classically presents with low CSF glucose (<40 mg/dL or <60% serum), elevated protein, PMN pleocytosis, and turbid appearance.
Question 5: A patient with Guillain-Barré syndrome has a forced vital capacity (FVC) of 15 mL/kg. The nurse anticipates:
- Elective intubation for airway protection (Correct answer)
- Initiation of plasmapheresis
- Administration of IV immunoglobulin
- Urgent lumbar puncture
Correct answer: Elective intubation for airway protection
FVC <20 mL/kg (or <1L) in GBS indicates impending respiratory failure and is the threshold for elective intubation before crisis occurs.
Question 6: Which nursing intervention is contraindicated in a patient with a basilar skull fracture?
- Nasogastric tube insertion (Correct answer)
- Oral suctioning
- Elevating the head of the bed 30 degrees
- Applying ice to periorbital ecchymosis
Correct answer: Nasogastric tube insertion
Nasogastric tube insertion is contraindicated in basilar skull fractures due to the risk of inadvertent intracranial placement through the fractured base.
Question 7: A patient on phenytoin therapy presents with nystagmus, ataxia, and diplopia. The serum phenytoin level is 28 mcg/mL. This presentation is best described as:
- Phenytoin toxicity (Correct answer)
- Breakthrough seizure activity
- Phenytoin-induced hypersensitivity
- Subtherapeutic drug effect
Correct answer: Phenytoin toxicity
Nystagmus, ataxia, and diplopia at a level of 28 mcg/mL (therapeutic range 10–20 mcg/mL) indicate phenytoin toxicity (supratherapeutic).
CNRN Neuroscience Registered Nurse Certification 2
A patient with a subarachnoid hemorrhage suddenly develops severe vasospasm on day 4.
Which medication is the first-line prophylactic agent?