ORS solution does not contain?

SCTIMST Staff Nurse - 2015 (Set-B)

Pharmacology

Easy

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

Explanation

The current WHO-recommended reduced-osmolarity ORS formulation does not contain sodium bicarbonate.
Sodium bicarbonate was a component of the original ORS formula but was later replaced by trisodium citrate dihydrate.
Trisodium citrate is more stable, giving the ORS packets a longer shelf life, and is converted to bicarbonate in the body to correct acidosis.

Option A: Sodium chloride is a fundamental component of ORS. It is crucial for replacing sodium and chloride ions lost during diarrhea.
Option B: Potassium chloride is an essential ingredient in ORS. It replenishes potassium lost in diarrheal stools, which is vital for preventing hypokalemia and its complications like muscle weakness and cardiac arrhythmias.
Option C: Glucose is a critical component of ORS. Its primary function is to facilitate the absorption of sodium and water from the gut via the sodium-glucose co-transport pathway, which is the physiological basis of oral rehydration therapy.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Composition of Oral Rehydration Solution (ORS) as background academic context rather than a clinical decision trigger.
Nurses must educate caregivers on the correct preparation of ORS: one sachet must be mixed in exactly one litre of clean, safe water. Using incorrect volumes can make the solution too concentrated (hypertonic) or too dilute, reducing its effectiveness.
The prepared ORS solution should be covered and used within 24 hours. Any remaining solution after this period must be discarded to prevent bacterial contamination.
What if? If a child with diarrhea shows signs of severe dehydration (e.g., lethargy, unable to drink, sunken eyes, loss of skin turgor), the priority is immediate intravenous (IV) fluid resuscitation, typically with Ringer's Lactate. ORS is for mild to moderate dehydration and for maintenance after IV therapy.

How to Approach the Question

First, identify the core of the question, which is to find the substance that is NOT a component of the standard ORS.
This is a factual recall question based on community health nursing and pharmacology.
Recall the composition of the current WHO-recommended reduced-osmolarity ORS formula.
Systematically evaluate each option: Sodium Chloride, Potassium Chloride, and Glucose are all known, essential components.
Recognize that Sodium Bicarbonate was part of the older formula but has been replaced by Trisodium Citrate in the current standard formulation for better stability.
Therefore, Sodium Bicarbonate is the correct answer as it is not present in the modern ORS.

Concept Tested & Keywords

Concept Tested: Composition of Oral Rehydration Solution (ORS)
Stem keywords: ORS solution, contain
Lead-in keywords: not
Negative lead-in flag: The question asks what is NOT included in an ORS solution, requiring careful elimination of the correct components.

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