Critical Care Registered Nurse (CCRN) Practice Exam

What is the primary method for assessing the vestibular component of CN VIII?

1. Checking symmetrical facial movements

2. Listening for voice quality

3. Observing nystagmus and balance

4. Assessing tongue deviation

The correct answer is: Observing nystagmus and balance

The primary method for assessing the vestibular component of cranial nerve VIII (the vestibulocochlear nerve) involves observing nystagmus and balance. The vestibular component is responsible for maintaining equilibrium and spatial orientation, and it affects balance through its connection to the inner ear. Nystagmus, which is an involuntary eye movement that can indicate vestibular system dysfunction, is often assessed through specific maneuvers, like the Dix-Hallpike test or simple observation of eye movements when the patient is asked to focus on a target while the head is positioned in different ways. Analyzing a patient's balance, which can be tested through standing or walking assessments, provides additional insights into the integrity of the vestibular system. If a patient shows unsteadiness or abnormal eye movements, it could indicate an issue with the vestibular function, confirming the assessment. In contrast, checking facial movements pertains to the function of cranial nerve VII (the facial nerve), listening for voice quality relates to the function of cranial nerves involved in speech, and assessing tongue deviation primarily concerns the hypoglossal nerve (cranial nerve XII). These assessments do not evaluate the vestibular aspect of cranial nerve VIII. Thus, observing nystag