CNRN Neuroscience Registered Nurse Certification 3 — Questions and Answers
Question 1: A patient with ischemic stroke is being considered for IV alteplase. Which of the following is an absolute contraindication?
- Blood pressure of 195/105 mmHg that does not respond to two antihypertensive doses (Correct answer)
- Last known well time of 3.5 hours ago
- Age 85 years
- Serum glucose of 55 mg/dL at presentation
Correct answer: Blood pressure of 195/105 mmHg that does not respond to two antihypertensive doses
BP >185/110 mmHg that cannot be lowered and maintained is an absolute contraindication to IV tPA for acute ischemic stroke.
Question 2: The nurse is caring for a patient with status epilepticus who has received two doses of lorazepam without seizure cessation. The next priority medication is:
- Levetiracetam or fosphenytoin IV (Correct answer)
- Phenobarbital IM
- Oral valproic acid via NG tube
- Propofol infusion
Correct answer: Levetiracetam or fosphenytoin IV
After two benzodiazepine doses fail, second-line agents (fosphenytoin, levetiracetam, or valproate IV) are indicated per status epilepticus protocols.
Question 3: Which clinical sign distinguishes central herniation from uncal herniation in a deteriorating patient?
- Bilateral pinpoint pupils early in central herniation vs. ipsilateral blown pupil in uncal herniation (Correct answer)
- Fixed dilated pupils bilaterally in uncal herniation
- Contralateral Babinski sign in central herniation only
- Decorticate posturing exclusive to uncal herniation
Correct answer: Bilateral pinpoint pupils early in central herniation vs. ipsilateral blown pupil in uncal herniation
Central herniation causes early bilateral small pupils and gradual rostral-caudal deterioration, while uncal herniation classically presents with an ipsilateral dilated fixed pupil from CN III compression.
Question 4: A patient with a C4 spinal cord injury develops a sudden headache (9/10), diaphoresis above the injury level, and hypertension of 210/118 mmHg. The nurse's first action is:
- Sit the patient upright and search for a noxious stimulus below the injury level (Correct answer)
- Administer prescribed IV antihypertensive immediately
- Obtain a 12-lead ECG
- Call the physician for antihypertensive orders
Correct answer: Sit the patient upright and search for a noxious stimulus below the injury level
Autonomic dysreflexia requires immediate upright positioning to use orthostatic hypotension as a rapid intervention while simultaneously identifying and removing the offending stimulus (most commonly a full bladder).
Question 5: Which assessment finding indicates increasing intracranial pressure in a patient with a traumatic brain injury?
- Widening pulse pressure with bradycardia (Correct answer)
- Tachycardia with narrowing pulse pressure
- Hypotension with tachypnea
- Fever with diaphoresis
Correct answer: Widening pulse pressure with bradycardia
Cushing's triad (widening pulse pressure, bradycardia, and irregular respirations) signals critically elevated ICP and impending brainstem herniation.
Question 6: A nurse is caring for a patient receiving hypertonic saline (3% NaCl) for cerebral edema. Which lab value requires the most immediate intervention?
- Serum sodium of 162 mEq/L (Correct answer)
- Serum sodium of 148 mEq/L
- Serum osmolality of 310 mOsm/kg
- Serum potassium of 3.2 mEq/L
Correct answer: Serum sodium of 162 mEq/L
Serum sodium >160 mEq/L during hypertonic saline therapy indicates hypernatremia beyond the intended therapeutic range and risks central pontine myelinolysis and renal injury.
Question 7: A patient with myasthenia gravis crisis is admitted with dysphagia and respiratory distress. The nurse should prioritize:
- Assessing respiratory function and preparing for possible intubation (Correct answer)
- Administering pyridostigmine per the home schedule
- Initiating IVIG infusion immediately
- Performing a Tensilon (edrophonium) test
Correct answer: Assessing respiratory function and preparing for possible intubation
In myasthenic crisis, airway and respiratory status are the immediate priority; intubation may be necessary before disease-specific treatment.
CNRN Neuroscience Registered Nurse Certification 3
A patient with ischemic stroke is being considered for IV alteplase.
Which of the following is an absolute contraindication?