Background and methods: Chronic renal failure frequently is complicated by elevations in serum potassium, phosphate, and magnesium. Consequently, parenteral nutrition (PN) solutions used to treat malnourished patients with chronic renal failure usually are prepared with little supplementation of these cations. Four malnourished patients with chronic renal failure and electrolyte abnormalities are reported.
Results: Four patients developed significant hypophosphatemia 3 to 5 days after starting PN. Although carbohydrate infused via PN initially was not excessive (1.4 to 2.0 mg/kg/min), two patients received additional dextrose through continuous ambulatory peritoneal dialysis (CAPD). Two of the four patients received insulin during PN. Other electrolyte abnormalities included hypomagnesemia (1 patient) and hypokalemia (3 patients).
Conclusions: Malnourished patients with chronic renal failure receiving PN are at risk of developing electrolyte abnormalities, particularly hypophosphatemia. The electrolytes of these patients should be monitored closely when nutrition support is begun, and supplementation should be started as levels begin to fall within a normal range.