CNRN Practice Test Questions with 100% Certified
Answers
A patient with a known seizure disorder is admitted to the hospital with altered mental status. His
phenytoin (Dilantin) level is 35.6. What is the most appropriate action? - Correct Answer- Hold phenytoin
and rec heck a level the next day; a normal level 10-20 mcg/mL. Supratherapeutic levels can cause
confusion, nausea, urticaria, nystagmus, hypotension, and cardiac arrhythmias.
Which of the following are sources of an embolic stroke? - Correct Answer- Patent foramen ovale; A
patent foramen ovale (PFO) is a hole between the left and right atria of the heart. It normally closes
shortly after birth. This condition may cause the formation of clots which can travel to the brain leading to
a transient ischemic attack or stroke. Tx-antiplatelet meds or blood thinners. HTN, obesity and HDL are
risk factors for thrombotic stroke.
A patient c/o of a headache for the past several wks is dx with a subacute subdural hematoma. Which of
the following is not an appropriate course of action? - Correct Answer- Administer levetiracetam
(Keppra); Antiepileptic drugs are not indicated for subacute hemorrhagic brain injuries. The greatest risk
of seizure is in the first two weeks following the incident. If no seizure has occurred during this time then
antiepileptic drugs do not need to be prescribed for the patient.
Which of the following regarding astrocytomas is NOT correct? - Correct Answer- Grace IV
astrocytomas are benign; Astrocytomas arise from astrocytes, which are a type of glial cell; they are the
most common glial tumor. Surgical resection in conjunction with chemotherapy and radiation are
common treatments. Grade I and II are generally benign slow growing tumors seen in children, whereas
grades III and IV are malignant and typically seen in adults.
A pt is dx with amyotrophic lateral sclerosis (ALS) and the pt's wife is concerned abt their children
developing this condition. Which of the following is an appropriate response? - Correct Answer- Its
etiology is unknown; this neuromuscular degenerative disease occurs at random with no clearly
associated risk factors. Individuals with this sporadic form of the disease do not have a family history of
ALS, and their family members not considered to be at increased risk for developing it. In a small
majority of cases occur with a family hx of this disease. Multiple gene mutations are involved with
developing this condition.
A pt presents with unilateral sharp, throbbing HA associated with eye pain and watering. What is the most
likely dx? - Correct Answer- Cluster headache; due to unknown etiology. They are characterized by
, unilateral symptoms that may involve the eye on the ipsilateral side. Tx-triptan drugs, calcium channel
blockers, and steroids.
A child is born with dozens of cafe-au-lait spots and axillary freckling. What is the most likely dx? -
Correct Answer- Neurofibromatosis; occurs d/t a genetic defect, which causes tumors to arise from nerve
cells. Complications that may occur from this disorder include deafness, HTN, seizures, hydrocephalus,
scoliosis, pathologic fxs, kyphosis, and vision problems. Common signs and symptoms include light
brown spots on the skin alled cafe-au-lait spots, abnormal development of the spin, skull, or long bones,
freckling in the are of the armpit or the groin. and disturbances in balance.
A child with spinal bifida develops worsening headaches and visual problems. An MRI of the brain
reveals herniation of the brainstem and lower part of the cerebellum extending into the foramen magnum.
Which type of Chiari malformation does this condition describe? - Correct Answer- Type II; the most
common type of Chiari malformation. Type I is where the lower part of the cerebellum, but not the
brainstem extends into the foramen magnum. Type III is where part of the cerebellum and the brainstem
extend through the foramen magnum into the spinal cord causing severe neurologic impairment. Chiari
malformation type IV is not associated with herniation of the brain through the foramen magnum; it
involves an underdeveloped cerebellum. This type is usually fatal in infancy.
Which of the following is the most common presenting symptom for Chiari malformation? - Correct
Answer- Occipital headaches; caused by the herniation of the brain through the skull base. Other signs
and symptoms include diplopia, nystagmus, visual changes, and balance difficulties.
A pt presenting with dysarthria and lethargy is being evaluated in the ER for possible stroke. The pt has
Glasgow Coma Scale (GCS) of 12, BP of 150/72, pulse ox of 96% on room air, BG of 43, and pt scores a
9 on the NIHSS. What is the best next step in intervention? - Correct Answer- Administer D50; if the pt's
neurological exam doesn't improve once the BG normalizes, then obtaining a CT of the head would be
appropriate. If the CT of the head is negative then administering tPA would be the next step if there are no
contraindications (and the BG has stabilized). The pt's GCS is 12; not sufficiently low enough to warrant
intubation.
Which of the following is true regarding multiple sclerosis (MS)? - Correct Answer- MS is an
autoimmune disease; A chronic progressive autoimmune disease that attacks the myelin sheath of nerve
cells. It can occur at any point in life but is most common in the third and fifth decades of life. It can
affect either sex, but affects women more than men. There is no cure but immunosuppressive meds,
muscle relaxers, and steroids may help with symptomatic relief of acute flare-ups. For unknown reasons it
is more common to people indigenous to temperate climates such as the United States and Europe.
Answers
A patient with a known seizure disorder is admitted to the hospital with altered mental status. His
phenytoin (Dilantin) level is 35.6. What is the most appropriate action? - Correct Answer- Hold phenytoin
and rec heck a level the next day; a normal level 10-20 mcg/mL. Supratherapeutic levels can cause
confusion, nausea, urticaria, nystagmus, hypotension, and cardiac arrhythmias.
Which of the following are sources of an embolic stroke? - Correct Answer- Patent foramen ovale; A
patent foramen ovale (PFO) is a hole between the left and right atria of the heart. It normally closes
shortly after birth. This condition may cause the formation of clots which can travel to the brain leading to
a transient ischemic attack or stroke. Tx-antiplatelet meds or blood thinners. HTN, obesity and HDL are
risk factors for thrombotic stroke.
A patient c/o of a headache for the past several wks is dx with a subacute subdural hematoma. Which of
the following is not an appropriate course of action? - Correct Answer- Administer levetiracetam
(Keppra); Antiepileptic drugs are not indicated for subacute hemorrhagic brain injuries. The greatest risk
of seizure is in the first two weeks following the incident. If no seizure has occurred during this time then
antiepileptic drugs do not need to be prescribed for the patient.
Which of the following regarding astrocytomas is NOT correct? - Correct Answer- Grace IV
astrocytomas are benign; Astrocytomas arise from astrocytes, which are a type of glial cell; they are the
most common glial tumor. Surgical resection in conjunction with chemotherapy and radiation are
common treatments. Grade I and II are generally benign slow growing tumors seen in children, whereas
grades III and IV are malignant and typically seen in adults.
A pt is dx with amyotrophic lateral sclerosis (ALS) and the pt's wife is concerned abt their children
developing this condition. Which of the following is an appropriate response? - Correct Answer- Its
etiology is unknown; this neuromuscular degenerative disease occurs at random with no clearly
associated risk factors. Individuals with this sporadic form of the disease do not have a family history of
ALS, and their family members not considered to be at increased risk for developing it. In a small
majority of cases occur with a family hx of this disease. Multiple gene mutations are involved with
developing this condition.
A pt presents with unilateral sharp, throbbing HA associated with eye pain and watering. What is the most
likely dx? - Correct Answer- Cluster headache; due to unknown etiology. They are characterized by
, unilateral symptoms that may involve the eye on the ipsilateral side. Tx-triptan drugs, calcium channel
blockers, and steroids.
A child is born with dozens of cafe-au-lait spots and axillary freckling. What is the most likely dx? -
Correct Answer- Neurofibromatosis; occurs d/t a genetic defect, which causes tumors to arise from nerve
cells. Complications that may occur from this disorder include deafness, HTN, seizures, hydrocephalus,
scoliosis, pathologic fxs, kyphosis, and vision problems. Common signs and symptoms include light
brown spots on the skin alled cafe-au-lait spots, abnormal development of the spin, skull, or long bones,
freckling in the are of the armpit or the groin. and disturbances in balance.
A child with spinal bifida develops worsening headaches and visual problems. An MRI of the brain
reveals herniation of the brainstem and lower part of the cerebellum extending into the foramen magnum.
Which type of Chiari malformation does this condition describe? - Correct Answer- Type II; the most
common type of Chiari malformation. Type I is where the lower part of the cerebellum, but not the
brainstem extends into the foramen magnum. Type III is where part of the cerebellum and the brainstem
extend through the foramen magnum into the spinal cord causing severe neurologic impairment. Chiari
malformation type IV is not associated with herniation of the brain through the foramen magnum; it
involves an underdeveloped cerebellum. This type is usually fatal in infancy.
Which of the following is the most common presenting symptom for Chiari malformation? - Correct
Answer- Occipital headaches; caused by the herniation of the brain through the skull base. Other signs
and symptoms include diplopia, nystagmus, visual changes, and balance difficulties.
A pt presenting with dysarthria and lethargy is being evaluated in the ER for possible stroke. The pt has
Glasgow Coma Scale (GCS) of 12, BP of 150/72, pulse ox of 96% on room air, BG of 43, and pt scores a
9 on the NIHSS. What is the best next step in intervention? - Correct Answer- Administer D50; if the pt's
neurological exam doesn't improve once the BG normalizes, then obtaining a CT of the head would be
appropriate. If the CT of the head is negative then administering tPA would be the next step if there are no
contraindications (and the BG has stabilized). The pt's GCS is 12; not sufficiently low enough to warrant
intubation.
Which of the following is true regarding multiple sclerosis (MS)? - Correct Answer- MS is an
autoimmune disease; A chronic progressive autoimmune disease that attacks the myelin sheath of nerve
cells. It can occur at any point in life but is most common in the third and fifth decades of life. It can
affect either sex, but affects women more than men. There is no cure but immunosuppressive meds,
muscle relaxers, and steroids may help with symptomatic relief of acute flare-ups. For unknown reasons it
is more common to people indigenous to temperate climates such as the United States and Europe.
