Electrolyte abnormalities in CKD are numerous and have multiple adverse clinical outcomes. Early intervention and management, especially of metabolic acidosis and hyperphosphatemia, can have a significant effect, including prevention of progression of CKD and possibly reduced mortality.
Dr. Daya, Dr. Apgar, and Dr. Eniasivam are assistant clinical professors in the division of hospital medicine at the University of California, San Francisco.
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1. Chapter 3: Management of Progression and Complications of CKD. Kidney Int Suppl (2011). 2013 Jan:3(1):73-90.
2. Raphael KL. Approach to the treatment of chronic metabolic acidosis in CKD. Am J Kidney Dis. 2016 Apr;67(4):696-702.
A 75-year-old male with hypertension and CKD Stage 4 is admitted to the hospital for a hip fracture following a fall. Laboratory studies on admission show a potassium level of 3.2 mEq/L, vitamin D level of 45 ng/mL, bicarbonate level of 17 mEq/L, phosphate level of 5.0 mg/dL, and calcium level of 10.3 mg/dL.
What electrolyte replacements should be initiated?
A. Dietary restriction of phosphate, sodium bicarbonate, potassium chloride, and vitamin D.
B. Non–calcium-containing phosphate binder, vitamin D, and potassium chloride.
C. Calcium-containing phosphate binder and sodium bicarbonate.
D. Non–calcium-containing phosphate binder, sodium bicarbonate, and potassium chloride.
Answer: D. Given the patient’s hypokalemia, potassium supplementation should be considered. Additionally, given his hyperphosphatemia and hypercalcemia, a non–calcium-containing phosphate binder like Sevelamer should be started. His metabolic acidosis should be corrected with sodium bicarbonate. There is no indication to supplement vitamin D based on his current lab values.
- Identify and treat underlying causes of hypokalemia and hypomagnesemia.
- Do not hesitate to treat metabolic acidosis in CKD.
- Manage hyperphosphatemia and hypocalcemia by ordering appropriate lab studies and providing nutritional consultation with outpatient nephrology follow-up as indicated.