Free CNRN Exam Questions That Helps Candidates Pass

Comprehensive and Detailed Explanation:

A sudden decline in level of consciousness in traumatic brain injury is a red flag for rising intracranial pressure, cerebral edema, or impending brain herniation. This is one of the most sensitive indicators of neurological deterioration. Normal fatigue or anxiety does not typically cause progressive drowsiness with reduced arousal in a monitored neuro patient. Medication effects may contribute but must be assumed secondary until life-threatening causes are ruled out. Immediate neurological assessment and escalation of care are required.

Comprehensive and Detailed Explanation:

Bacterial meningitis typically shows low CSF glucose due to bacterial consumption and high neutrophils due to acute inflammatory response. Protein is also elevated. This pattern differentiates bacterial from viral meningitis. Normal glucose with lymphocytes suggests viral infection. Absence of white blood cells is not compatible with meningitis.

Comprehensive and Detailed Explanation:

The right cerebral hemisphere controls motor and sensory function on the left side of the body. Therefore, left facial droop and right arm weakness suggest a right hemispheric stroke affecting motor pathways. Cerebellar lesions cause coordination and balance issues, not focal unilateral weakness. Brainstem strokes often cause cranial nerve deficits and bilateral findings. Occipital lobe strokes primarily affect vision.

Comprehensive and Detailed Explanation:

Posterior fossa tumors often involve the brainstem and cranial nerves, leading to dysphagia (CN IX and X dysfunction), facial weakness (CN VII), and other cranial nerve deficits. These tumors can also affect coordination. Loss of smell is associated with CN I and anterior fossa lesions. Hearing improvement and enhanced vision are not associated with tumor involvement.

Comprehensive and Detailed Explanation:

Mannitol is an osmotic diuretic used to reduce intracranial pressure by drawing fluid from cerebral tissues into the intravascular space. While increased urine output and reduced ICP are expected therapeutic effects, a major complication is fluid overload leading to pulmonary edema. Pulmonary crackles and worsening oxygenation suggest that fluid has shifted excessively into the intravascular compartment, stressing cardiac and pulmonary systems. This requires immediate reassessment of fluid status and possible adjustment of therapy. Improved neurological status and reduced ICP are desired outcomes, not complications.