A 9 year old girl was admited for dialysis. On laboratory examination her potassium levels were 7.8 mEq/L. Which of the following would quickly lower her increased potassium levels-: (A) IV calcium gluconate, (B) IV Glucose and insulin, (C) Oral kayexalate in sorbitol, (D) IV NaHCO3
Answer is B. Insulin lowers plasma K+ concentration by shifting K+ into cells. The recommended dose is 10 units of intravenous regular insulin followed immediately by 50 mL of 50% dextrose (D50W, 25 g of glucose total); the effect begins in 10-20 min, peaks at 30-60 min, and lasts for 4-6 h. (ref: harrisons. 19E pg 312)