The normal range of sodium in blood is:

Appeared in: AIIMS BHOPAL NO- 2018( Shift-2nd)

Explanation

The correct range for serum sodium is 135 to 145 milliequivalents per liter (mEq/L).
Sodium is the primary cation in the extracellular fluid (ECF) and is the main determinant of extracellular osmolality.
The unit of measurement, mEq/L, is standard for reporting electrolyte concentrations in blood plasma or serum.
This concentration is essential for maintaining intravascular volume, blood pressure, and nerve function.

Option A: The unit of measurement is incorrect. While the numerical value (135-145) is correct, the unit is milliequivalents per milliliter (mEq/mL).
Option C: Both the numerical value (5-5.5) and the unit (mEq/mL) are incorrect for serum sodium.
Option D: The numerical value (5-5.5) is incorrect for sodium. This range is characteristic of serum potassium (K+).

Clinical Relevance

Nursing practice connection: Knowing Normal serum sodium level helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
Monitoring serum sodium is a fundamental nursing responsibility, as imbalances can lead to serious neurological, cardiovascular, and musculoskeletal problems.
Nurses must be vigilant in assessing for signs of hyponatremia (e.g., confusion, seizures, coma) and hypernatremia (e.g., thirst, lethargy, irritability, seizures).
Patient education is crucial, especially for those on diuretics, with heart failure, or with kidney disease, regarding dietary sodium intake and signs of imbalance.

How to Approach the Question

This is a factual recall question. First, identify the specific electrolyte mentioned: sodium (Na+).
Recall the normal physiological range for that electrolyte from your knowledge base.
Pay very close attention to the units of measurement provided in the options. In this case, the distinction between mEq/L and mEq/mL is the critical differentiator between the correct answer and a key distractor.
Eliminate options with incorrect numerical values. The range of 5-5.5 is for potassium, not sodium.
Select the option that has both the correct numerical value (135-145) and the correct unit of measurement (mEq/L).

Concept Tested & Keywords

Q3qc1qSdRDKbKg7AHNAJNs

E6 Nursing Fundamentals Potter Perry 12e Part 5 p. 47-49

E6 Pharmacology Nursing Lilley 11e Part 2 p. 169-171

E6 Nelson Textbook of Pediatrics(2024) — Volume 1 p. 534-536

Practise the full AIIMS BHOPAL NO- 2018( Shift-2nd)

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