A client with acute renal injury (AKI) weighs 110.3 pounds (50 kg) and has a potassium level of 6.7 mEq/L (6.7 mmol/L) is admitted to the hospital. Which prescribed medication should the nurse administer first?
Reference Range:
Potassium [3.5 to 5 mEq/L (3.5 to 5 mmol/L)]
A Sodium polystyrene sulfonate 15 grams by mouth.
B Sevelamer one tablet by mouth.
C Calcium acetate one tablet by mouth.
D Epoetin alfa, recombinant 2,500 units subcutaneously.
E Calcium acetate one tablet by mouth.
The correct answer and Explanation is :
The correct answer is A. Sodium polystyrene sulfonate 15 grams by mouth.
Explanation:
The client’s potassium level of 6.7 mEq/L is critically high, indicating hyperkalemia. Normal potassium levels range from 3.5 to 5.0 mEq/L, and levels above 6.0 mEq/L pose a significant risk for life-threatening cardiac arrhythmias. Hyperkalemia can result in muscle weakness, fatigue, and the most severe consequence—cardiac arrest. Thus, addressing hyperkalemia is the priority.
Why Sodium Polystyrene Sulfonate (A) First?
Sodium polystyrene sulfonate (also known as Kayexalate) works by binding potassium in the intestines and promoting its excretion through the stool. It is a commonly prescribed treatment for hyperkalemia, especially in the context of acute kidney injury (AKI), where the kidneys cannot excrete potassium efficiently. While it may not act as quickly as intravenous medications like calcium gluconate or insulin with glucose (often used in emergency settings), it still plays a significant role in potassium reduction over a few hours. Given that the medication is prescribed and available, it should be administered promptly to start lowering potassium levels.
Why Not the Other Options?
- B. Sevelamer: This is a phosphate binder, used to manage high phosphate levels in patients with chronic kidney disease (CKD). It does not address hyperkalemia and is not the priority.
- C. Calcium acetate: Also a phosphate binder for managing hyperphosphatemia in CKD, it does not affect potassium levels and is not critical in this situation.
- D. Epoetin alfa: This is used to stimulate red blood cell production in patients with anemia, typically due to CKD. It does not have an immediate effect on hyperkalemia and is not a priority in this acute situation.
Given the life-threatening nature of hyperkalemia, the most urgent need is to lower the potassium level, making sodium polystyrene sulfonate the correct choice.