The normal volume of cerebrospinal fluid (CSF) is?

Appeared in: ISRO- 2016

Explanation

The normal total volume of cerebrospinal fluid (CSF) in an adult is approximately 150 mL, fitting within the 125-150 mL range.
CSF is produced by the choroid plexus in the brain's ventricles and serves to cushion the central nervous system, transport nutrients, and remove waste.
The body produces about 500 mL of CSF daily, meaning the entire volume is replaced approximately 3 to 4 times each day.
This specific physiological range is a key parameter for assessing neurological health.

Option A: This volume (25-50 mL) is significantly below the normal adult range.
Option B: This range (50-100 mL) is also below the accepted physiological standard for an adult's CSF volume.
Option D: The upper limit of this range (200 mL) exceeds the normal physiological volume.

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.
Knowledge of normal CSF volume is essential for nurses assisting with procedures like a lumbar puncture (spinal tap), where CSF is removed for diagnostic testing.
During a lumbar puncture, the opening pressure is measured (normal: 10–18 cm H₂O). Deviations from normal volume or pressure can indicate conditions like hydrocephalus (high pressure/volume) or a CSF leak (low pressure/volume).
Nurses must monitor patients for post-lumbar puncture headaches, which are often caused by a temporary reduction in CSF volume and pressure.

How to Approach the Question

This is a factual recall question that tests your knowledge of a specific physiological value.
Identify the core concept being asked: the 'normal volume' of 'cerebrospinal fluid (CSF)' in an adult.
Recall the standard physiological value. The average adult CSF volume is approximately 150 mL.
Scan the given options to find the range that includes this value.
The range '125-150 ml' is the most accurate and widely accepted answer.
Eliminate other options by recognizing they are either too low (characteristic of infants) or too high (suggesting a pathological condition).

Concept Tested & Keywords

QMyg2NnysUv5teFRDiN2OT

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

E6 Medicine Davidson Principles Practice 24e p. 1098-1100

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