A post operative patient is receiving dextrose 5% and 0.45 normal saline at 160 ml/hour. The nurse notices puffiness, weight gain of 2 kg and hypotension with complaints of muscle cramps and confusion. The serum sodium level is 126 mEq/L. Which of the following is the most likely cause of these findings?

1. A

   Hyperglycemia and hyponatremic dehydration

2. B

   Dehydration and Potassium deficiency

3. C

   Excessive dietary sodium and hyperglycemia

4. D

   Fluid overload and hyponatremia

Appeared in: RRB Nsg. Superintendent-2026 (Shift -1st)

Explanation

• The patient's signs of puffiness and a 2 kg weight gain are classic indicators of fluid volume excess (fluid overload).
• The intravenous fluid, D5 0.45% NS, becomes hypotonic in the body after the dextrose is metabolized. The high infusion rate (160 ml/hr) has led to an excess of free water, diluting the blood.
• The serum sodium level of 126 mEq/L is below the normal range (135-145 mEq/L), confirming hyponatremia.
• Neurological symptoms like confusion and muscle cramps are hallmark signs of hyponatremia, caused by cerebral edema as water shifts into brain cells.

Why Other Options Were Wrong

• Option A: This option is incorrect because the patient shows clear signs of fluid overload (weight gain, puffiness), not dehydration. Dehydration involves fluid loss and would present with weight loss and poor skin turgor.
• Option B: Dehydration is contradicted by the patient's 2 kg weight gain and puffiness. While muscle cramps can occur with potassium deficiency, the primary evidence (low sodium, confusion) points strongly to hyponatremia.
• Option C: This option is incorrect because excessive sodium intake would cause hypernatremia (high sodium levels, greater than 145 mEq/L). The patient's lab result shows hyponatremia (low sodium level of 126 mEq/L).

Related Visual

• Visual 1: Diagram: Illustrating the fluid shift in hyponatremia. This visual would show water moving from the low-osmolality extracellular space into the higher-osmolality intracellular space (including brain cells), causing them to swell.
• Visual 2: Flowchart: Depicting the pathophysiology. It would start with 'Rapid infusion of hypotonic IV fluid' leading to two branches: 'Increased total body water' (causing fluid overload, edema, weight gain) and 'Dilution of serum sodium' (causing hyponatremia, which leads to neurological symptoms).

Clinical Relevance

• Nursing practice connection: Knowing Assessment and management of fluid and electrolyte imbalances, specifically hypervolemic hyponatremia helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
• Nurses must critically monitor patients receiving IV fluids, especially hypotonic or near-hypotonic solutions at high rates, for early signs of fluid overload (e.g., crackles in lungs, edema, weight gain) and hyponatremia (e.g., headache, confusion).
• Recognizing early neurological changes is critical for patient safety. A change in mental status in a patient receiving IV fluids should immediately prompt the nurse to consider an electrolyte imbalance like hyponatremia.
• Patient safety depends on prompt intervention. If fluid overload and hyponatremia are suspected, the nurse should slow the IV rate (as per protocol or after notifying the provider), raise the head of the bed, and prepare for potential orders like fluid restriction or diuretics.

How to Approach the Question

• First, analyze the patient data provided in the stem: the type and rate of IV fluid (D5 0.45% NS @ 160ml/hr), physical assessment findings (puffiness, weight gain), vital signs (hypotension), symptoms (cramps, confusion), and the lab value (sodium 126 mEq/L).
• Correlate the findings. Link the high IV rate, weight gain, and puffiness to a fluid volume status. These signs point to fluid overload, not dehydration.
• Interpret the lab value. A serum sodium of 126 mEq/L is low, confirming hyponatremia.
• Connect the pathophysiology. Understand that infusing a fluid that acts as a hypotonic solution (0.45% NS after dextrose is used) can dilute serum sodium, causing hyponatremia, and the high volume leads to overload.
• Synthesize the information. The patient has both fluid overload and hyponatremia.
• Evaluate the options based on this synthesis. The combination of 'Fluid overload and hyponatremia' is the only option that explains all the patient's signs and symptoms.

Concept Tested & Keywords

• Concept Tested: Assessment and management of fluid and electrolyte imbalances, specifically hypervolemic hyponatremia.
• Stem keywords: post operative, dextrose 5% and 0.45 normal saline, 160 ml/hour, puffiness, weight gain, hypotension, muscle cramps, confusion
• Lead-in keywords: most likely cause
• Clinical cues: IV fluid type and rate: D5 0.45% NS at 160 ml/hr is a high rate of a hypotonic-acting fluid, predisposing to fluid overload and dilution.
• Clinical cues: Weight gain of 2 kg: A rapid weight gain is a strong indicator of fluid retention, not dehydration.

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Qc6Q2671v4vH3AEXOV_eYr

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