Which of the following would be the plasma osmolatity of child with plasma Na+ 125 mEq/L, glucose of 108mg/d1, and blood urea nitrogen (BUN) of 140 mg/dl -
High-Yield Explanation
Ans. is `b' i.e., 306 mOsm/kg Osmolality = 2 (Na+) + .055 + .36 (mOSM/L (meq/L) (mg/dl) (mg/dl). o Replacing values given in the question. Osmolaity = 2 (125 meq/1) + .055X108mg/dL+.36 X 140mg dL = 306 mOsm/L.