The Certified Neuroscience Registered Nurse examination, commonly known as the CNRN Exam, is a challenging and comprehensive assessment for men and women who want to enter this exciting area of healthcare. The exam covers the following areas of trauma: traumatic brain injury (blast, bunt, penetrating); hematoma (chronic subdural, acute subdural, epidural); diffuse axonal injury; contusions; fractures (spinal column, skull); spinal cord injury; herniated nucleus pulposus; peripheral nerve injury; and repetitive stress injury (e.g., carpal tunnel syndrome, lumbar/cervical strain).
The following cerebrovascular events are covered by the exam: transient ischemic attack; aneurysm; arterio-venous malformation; arterio-venous fistula; carotid stenosis; cavernous angiomas; dural arterial-venous fistula; carotid dissection; ischemic stroke (thrombotic, embolic, lacunar); hemorrhagic stroke (intracerebral hemorrhage, subarachnoid hemorrhage, intraventricular hemorrhage); and headaches (acute, chronic).
Regarding tumors, the CNRN exam addresses brain tumors (neuroepithelial tissue, cranial and spinal nerves, meningeal and related tissues, hematopoietic, pituitary, metastatic, and other) and spinal cord tumors (primary, metastatic, neurofibroma). With respect to immune/infection issues, the exam covers abscesses; amytrophic lateral sclerosis; AIDS; Bell’s palsy; encephalitis; Guillain-Barre; meningitis (viral, bacterial, fungal origin); multiple sclerosis; and myasthenia gravis. Regarding seizures, the exam addresses partial seizures, generalized seizures, status epilepticus, and pseudoseizures. The developmental and degenerative conditions covered by the CNRN exam include Arnold-Chiari malformation; cerebral palsy; hydrocephalus (communicating, obstructive, normal pressure); spina bifida; myelomeningocoele; and Down syndrome. This section also covers attention deficit hyperactivity disorder; dementia (Alzheimer’s disease, vascular); dystonia; Parkinson’s disease; peripheral neuropathy; benign essential tremor; degenerative spine disease (degenerative disk disease, vertebral compression fractures, lumbar spondylolisthesis, spinal stenosis); craniosynostosis; and balance and dizziness disorders (e.g., Meniere’s disease, Freiedrich’s ataxia). Other disorders covered by the exam include trigeminal neuralgia; sleep disorders; toxic encephalopathies; delirium; pain (acute, chronic); and chemical dependency.
CNRN Test Video Review
CNRN Practice Questions
1. The most essential element of respiratory monitoring of a patient hospitalized for management of Guillain-Barré syndrome is:
A. Measuring respiratory rate at frequent intervals
B. Checking frequently for signs of hypoxia, such as dyspnea, cyanosis, or confusion
C. Measuring oxygenation by continuous pulse oximetry
D. Measuring vital capacity at frequent intervals, and knowing the value at which intubation will be performed electively
2. Once a patient has become HIV-positive, the most effective way to prevent AIDS-dementia complex (ADC) is which of the following?
A. Isolation precautions to prevent opportunistic CNS infections, such as tuberculosis
B. Prophylaxis with cholinergic medications such as donepezil
C. Aggressive cognitive stimulation
D. Early and sustained HAART (highly active antiretroviral therapy)
3. The most accurate statement concerning patient age and treatment outcomes for cerebral aneurysm is:
A. For all accepted types of treatment, outcomes are not correlated with age.
B. Above age 65, there is a higher incidence of negative treatment outcomes, even though the surgical complication rate is the same.
C. Above age 65, the incidence of negative treatment outcomes and the incidence of surgical complications are both higher.
D. Only ultra-soft coils have an acceptable success rate in patients over age 65.
4. While carefully monitoring the neurologic examination in a patient receiving a continuous intravenous heparin for cerebral venous thrombosis (CVT), the nurse notes an acute neurologic deficit. The immediate response should be:
A. Discontinue the heparin and notify the physician at once
B. Elevate the head of the bed and make sure the head remains positioned at 30 degrees
C. Assess the patient with PTT and CT scan of the brain
D. Obtain PTT and empirically increase the heparin infusion slightly pending the result
5. A 23 year-old woman with a diagnosis of hemifacial spasm has had no benefit from decompression surgery. In fact, at surgery, no aberrant blood vessel was found in the vicinity of cranial nerve VII. She refuses anticonvulsant medication because she would like to become pregnant. The next step in her management should be:
A. A new MRI scan, with double gadolinium and FLAIR sequences
B. Psychiatric consultation and behavior management, including relaxation techniques
C. Botulinum toxin
D. Dental consultation to look for intraoral pathology that could be stimulating the unwanted movements
6. The most serious complication of pseudotumor cerebri is:
A. Herniation of the cerebellar tonsils through the foramen magnum
D. Status epilepticus
7. Levodopa is used instead of dopamine itself to treat symptoms of Parkinson ‘s disease because:
A. Levodopa is more potent than dopamine
B. Levodopa crosses the blood-brain barrier, and dopamine does not
C. Levodopa can be given with carbidopa, and dopamine cannot
D. Levodopa is not associated with side effects such as psychosis
8. A child with Down syndrome who has been progressing well in school begins to have trouble paying attention in class and fails to learn new material without a great deal of repetition, but does not lose previously acquired cognitive skills. The diagnostic test most likely to provide a relevant diagnosis is:
9. The most effective strategy to date for limiting cognitive impairment in patients with multiple sclerosis (MS) is:
A. Oral memantine
B. Early intervention with disease-modifying agents
C. Oral donepezil
D. Oral l-amphetamine
10. When a woman known to have multiple sclerosis (MS) gives birth:
A. She should not have epidural anesthesia because of the risk of producing an exacerbation.
B. She should be advised to choose Caesarean section, especially if she has prominent motor weakness.
C. A pediatrician should be present at the delivery because of the risk of respiratory compromise in the infant.
D. Her choice of interventions for pain should be made based on the same obstetric considerations and personal preferences as for any other woman.
1. D: Respiratory failure is a common feature of Guillain-Barré syndrome and occurs because of neuromuscular weakness, not intrinsic lung pathology. When the cause of respiratory failure is neuromuscular, the patient may deteriorate very abruptly without having had symptoms or signs of hypoxia in advance. Relying on the clinical picture alone or supplemented by pulse oximetry or even arterial blood gases can be falsely reassuring. Once the vital capacity falls below 12-15 mL/kg, the patient is at risk for ventilatory failure, and intubation should proceed regardless of the patient’s comfort level or other signs. Of course, measuring the respiratory rate and regularly ausculting the lungs are also important measures, but the most important element of respiratory monitoring is frequent vital capacity determination.
2. D: The pathophysiology of AIDS dementia complex is complex and includes entry of HIV into the brain within infected monocytes, widespread neuronal damage by cellular proteins and verotoxins, abnormal patterns of neurotransmitter release, and increased free intraneuronal calcium. HAART is thought to reduce entry of HIV into the central nervous system and to reduce neuronal damage by HIV once it has entered the CNS. HAART has significantly reduced the incidence of ADC in HIV-positive patients. In addition, HAART reduces severity and prolongs survival in cases of established ADC. Some patients with ADC also experience cognitive improvement with HAART treatment. There are no data to support the use of cholinesterase inhibitors.
3. A: Regardless of treatment for intracranial aneurysm, outcomes do not vary by age. Costs do increase in proportion to age and length of hospital stay. Early surgical repair can improve outcome and shorten hospital stay. Outcome data is a relevant and admissible factor in guiding treatment choices, but age is not a relevant or ethical criterion on which to base treatment choices for intracranial aneurysm.
4. A: Although anticoagulation with heparin is standard treatment in the acute phase of management of the patient with cerebral venous thrombosis, the risk of converting an ischemic infarct to a hemorrhagic infarct is substantial; as many as 40% of CVT patients actually have hemorrhagic infarcts even before starting IV heparin. Acute changes in neurologic status of patients with CVT should be treated as if for intracerebral hemorrhage pending further evaluation.
5. A: Hemifacial spasm is a syndrome, not a diagnosis. Hemifacial spasm is often caused by an aberrant blood vessel irritating the facial nerve at the cerebellopontine angle. Other compressive lesions may also produce hemifacial spasm. In this case, there was no aberrant vessel and presumably no other compressive lesion. The patient is atypical because of her age as hemifacial spasm presents most often in the 5th or 6th decade of life. Although hemifacial spasm can occur on an idiopathic basis, underlying neurologic disease has to be considered, especially given the patient’s age. She should be re-evaluated for multiple sclerosis, especially since this diagnosis could impact her decisions concerning if, when, and how to have children. Botulinum toxin may relieve her symptoms regardless of the cause, but further investigation at this point is essential. Some patients with orofacial dyskinesia have underlying dental abnormalities (often edentulousness) but the condition should be clinically distinguishable from hemifacial spasm and rarely affects young people, so dental consultation is not likely to produce useful information in this case. Psychiatric consultation may help the patient to cope with cosmetically distressing problem, but it will not yield diagnostic information or alleviate her symptoms.
6. C: Herniation is an extremely uncommon complication of pseudotumor cerebri because the increased pressure is diffuse and builds gradually. Visual loss may occur because of buildup of pressure within the optic nerve sheath, and surgical fenestration of the sheath may be a necessary emergency surgical intervention to preserve eyesight for patients whose intracranial pressure does not decline with medical management.
7. B: Although the exact cause of Parkinson’s disease is unknown, it is clear that at a neurochemical level, the fundamental problem is depletion of dopaminergic neurons in brainstem and subcortical brain structures, including the substantia nigra, locus ceruleus, globus pallidus, and putamen. The dopamine cannot be replaced directly, because it is destroyed in the systemic circulation before it can reach the blood-brain barrier. Levodopa escapes this peripheral metabolism and crosses the blood-brain barrier. Levodopa is associated with multiple side effects, such as psychosis, anorexia, nausea, and vomiting, which can seriously limit its use in some patients.
8. D: Sleep apnea is extremely common in children and adults with Down syndrome because of their soft tissue abnormalities, including protruding tongue, receding chin, and thick neck. In some studies, nearly 100% of patients with Down syndrome had some degree of sleep apnea. Parents generally underestimate their children’s sleep disturbance. Sleep apnea is a treatable cause of cognitive decline in any individual and a particularly important treatable cause of cognitive decline in individuals with Down syndrome. Epilepsy while slightly more common in individuals with Down syndrome than in the general population, is less prevalent than sleep apnea. Structural heart defects and rhythm disorders are also more common in the Down syndrome population, but less so than sleep apnea.
9. B: Multiple studies show consistently better cognitive function over time in multiple sclerosis (MS) patients who begin disease modifying therapy soon after diagnosis. Results are consistent for interferon and glatiramer acetate therapy with results influenced more by timing of intervention than by the choice of disease-modifying agent. Results with natalizumab are particularly striking, not only for prevention of long-term cognitive decline, but also for reversal of existing cognitive impairments and rapidity of onset of the effect. It is thought that most of the benefit conferred by disease-modifying agents is attributable to prevention of the inflammatory processes that dominate the early pathophysiology of MS and lead to the later, more refractory, degenerative pathophysiologic phases of MS.
10. D: In many hospitals, anesthesiologists refuse to provide epidural obstetric anesthesia to mothers with multiple sclerosis. The idea that epidural anesthesia can precipitate an exacerbation of MS, however, is entirely unsupported by clinical research. In some communities, the policy to withhold epidural anesthesia is based on fear of legal action if the woman does indeed have an exacerbation of her MS. Since the post-partum period is a time of heightened risk of exacerbation, the concern is understandable, but it is the sudden change in hormonal environment, not the epidural injection or anesthetic agent, that is responsible for the high rate of exacerbations in the weeks following childbirth. A newborn whose mother has multiple sclerosis is at no greater risk of medical complications than any other newborn. There should be no confusion with neonatal myasthenia gravis.