The normal volume of cerebrospinal fluid (CSF) is?

Appeared in: SCTIMST Staff Nurse - 2015 (Set-A)

Explanation

The normal volume of cerebrospinal fluid (CSF) in a healthy adult is approximately 125–150 mL.
This volume is maintained within the brain's ventricles and the subarachnoid space surrounding the brain and spinal cord.
The body produces about 500 mL of CSF per day, meaning the entire volume is replaced or turned over about 3 to 4 times daily.
This balance of production and absorption is crucial for maintaining normal intracranial pressure.

Option A: This volume is significantly below the normal range for an adult.
Option B: This range is also below the standard accepted physiological volume for an adult's central nervous system.
Option D: The upper end of this range (200 mL) exceeds the normal physiological limit. A volume consistently above 150 mL is considered abnormal.

Clinical Relevance

Nursing practice connection: Knowing Normal Cerebrospinal Fluid (CSF) Volume helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
Nurses play a key role during lumbar punctures (spinal taps) by positioning the patient, handling sterile equipment, and monitoring the patient's vital signs. Understanding normal CSF values helps in recognizing immediate signs of abnormality.
A sustained increase in CSF volume leads to increased intracranial pressure (ICP). Nurses must be vigilant in monitoring for signs of increased ICP, such as headache, nausea/vomiting, blurred vision, and changes in consciousness.
A sudden decrease in CSF volume, which can occur after a lumbar puncture, may cause a severe postural headache. Nursing interventions include encouraging the patient to lie flat and ensuring adequate hydration to help replenish CSF volume.

How to Approach the Question

Identify the core of the question: it asks for a specific, standard physiological value ('normal volume of CSF').
Recognize this as a factual recall question, which requires knowledge of normal human anatomy and physiology.
Scan the options provided; they are all numerical ranges.
Access your knowledge base to recall the standard CSF volume for an adult. Eliminate options that are clearly too low (like infant volumes) or too high (suggesting pathology).
Select the option that aligns with the established physiological norm, which is 125-150 mL.

Concept Tested & Keywords

QxQnoF5vc-AA5KgZdHsBNN

E6 Nelson Textbook of Pediatrics(2024) — Volume 2 p. 1383-1385

E6 Biochemistry U Satyanarayana— Part 2 (pp 421-820 of 840) p. 121-123

Practise the full SCTIMST Staff Nurse - 2015 (Set-A)

Attempt every question from this paper in a timed mock, then review the full solution for each one.