Question

Plasma Osmolality = x \(\times\) Plasma Na\(^+\) (mmol/L) + glucose (mg/dL)/18 + BUN (mg/dL)/2.8
Fill in the blank with the appropriate option:

• A. 2
• B. 12
• C. 20
• D. 5

Hint:

Plasma osmolality formula:
Osm = 2(Na\(^+\)) + Glucose/18 + BUN/2.8.
Normal range: 275-295 mOsm/kg.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Plasma osmolality is calculated using specific formula.
The formula includes sodium, glucose, and BUN.

Step 2: Key Formula or Approach:
Plasma Osmolality = 2 \(\times\) Plasma Na\(^+\) + glucose/18 + BUN/2.8.

Step 3: Detailed Explanation:
The standard formula for plasma osmolality is:
Osm = 2 \(\times\) Na\(^+\) + Glucose/18 + BUN/2.8.
The factor 2 accounts for chloride and bicarbonate ions.
Thus, the blank should be filled with 2.

Step 4: Final Answer:
The value is 2.
Hence, the correct option is (A).