CNRN Neuroscience Registered Nurse Certification 4

Question 1

Which EEG pattern is pathognomonic of herpes simplex encephalitis?

Accepted Answer

Periodic lateralized epileptiform discharges (PLEDs) in the temporal region

Answer

HSV encephalitis characteristically produces periodic lateralized epileptiform discharges (PLEDs) maximal in the temporal lobes, correlating with its predilection for temporal lobe involvement.

Question 2

A patient with Parkinson's disease is NPO post-operatively and cannot take oral carbidopa-levodopa. The nurse recognizes the greatest risk is:

Accepted Answer

Neuroleptic malignant-like syndrome from abrupt dopaminergic withdrawal

Answer

Abrupt withdrawal of dopaminergic therapy in Parkinson's disease can precipitate a potentially fatal neuroleptic malignant-like syndrome with hyperthermia, rigidity, and altered consciousness.

Question 3

The nurse is reviewing a patient's MRI report that states 'diffusion restriction in the left MCA territory.' This finding is most consistent with:

Accepted Answer

Acute ischemic stroke within hours of onset

Answer

Diffusion-weighted imaging (DWI) restriction indicates cytotoxic edema from acute ischemia, appearing within minutes and persisting for approximately 10–14 days.

Question 4

Which intervention is most appropriate for a patient with increased ICP who has a PaCO2 of 52 mmHg?

Accepted Answer

Increase ventilator rate to target PaCO2 35–40 mmHg

Answer

Hypercapnia causes cerebral vasodilation and worsens ICP; controlled ventilation targeting PaCO2 35–40 mmHg reduces ICP by promoting mild vasoconstriction.

Question 5

A patient post-transsphenoidal hypophysectomy develops polyuria with urine output of 600 mL/hr, urine specific gravity of 1.001, and serum sodium of 149 mEq/L. The nurse should prepare to administer:

Accepted Answer

Desmopressin (DDAVP)

Answer

These findings indicate central diabetes insipidus from posterior pituitary damage; DDAVP (synthetic ADH) is the treatment of choice.

CNRN Test Practice Test

CNRN Test Practice Test

CNRN Neuroscience Registered Nurse Certification 4