A lethargic patient has fever, vomiting, headache and the nurse has to prepare him for which one of the following procedure?

Correct option is B

Fever, headache, vomiting, and lethargy are classic signs of meningitis. To confirm the diagnosis, a lumbar puncture (LP) is done to collect cerebrospinal fluid (CSF) and assess for infection. Explanation of each option: • (a) Blood culture – Useful to identify septicemia, but it does not diagnose meningitis directly. It’s usually done in addition to LP. • (b) Lumbar puncture – Correct. It is the gold standard for diagnosing central nervous system infections like meningitis by analyzing CSF for WBCs, protein, glucose, and pathogens. • (c) CAT scan – A CT scan may be performed before LP if increased intracranial pressure is suspected, but LP is definitive for diagnosis. • (d) Ultrasound exam – Not helpful in diagnosing meningitis. Ultrasound is more applicable for abdominal, renal, or obstetric evaluations.