Association between intravenous phosphate repletion and serum phosphate relative to enteral repletion in hospitalized adults: A retrospective cohort study.

BACKGROUND: Enteral phosphate repletion may reduce the need for fluid replacement, decrease costs, and minimize waste. Enteral repletion has been previously shown to be noninferior to intravenous (IV) repletion. The primary objective of this study was to evaluate the association between IV and enteral phosphate repletion and 24-h serum phosphate response in hospitalized patients with hypophosphatemia. METHODS: This was a retrospective, multicenter, observational study. Patients were included if they received at least one dose of IV or enteral phosphate with a serum phosphate level of <2.5 mg/dL. The primary outcome was the change in 24-h serum phosphate level between IV and enteral repletion groups. RESULTS: A total of 2567 patients met inclusion criteria and 124 were selected randomly for feasibility. Ninety-eight (79%) patients received IV repletion and 26 (21%) patients received enteral repletion. Sixty-eight (69.4%) patients receiving IV phosphate were eligible to receive enteral phosphate. Change in 24-h serum phosphate was similar between enteral and IV groups [0.7 (0.5) vs. 1.2 (1.4); P = 0.07]. No patients in either group developed severe hypophosphatemia (<1 mg/dL) during the study period. CONCLUSION: IV and enteral phosphate repletion resulted in similar changes in serum levels without the development of severe hypophosphatemia. Most patients who received IV phosphate repletion were eligible to receive enteral repletion. These findings support the feasibility of enteral phosphate repletion in appropriately selected patients with mild to moderate hypophosphatemia.