Association between dextrose-containing maintenance fluids and phosphorus supplementation during total parenteral nutrition initiation in adult patients who were hospitalized: A retrospective cohort study.

Abstract

Use of dextrose-containing maintenance fluids prior to parenteral nutrition (PN) initiation is speculated to reduce the risk for refeeding syndrome. We aimed to assess if the use of dextrose vs nondextrose maintenance fluids before PN initiation changes electrolyte supplementation requirements and shifts during initiation. This retrospective cohort study included patients who received nothing by mouth but received maintenance fluids ≥72 h before PN. The major end point was phosphorus supplementation over 48 h following nutrition initiation. Minor end point included other electrolyte supplementation, changes in electrolyte levels, time to discharge, and goal kilocalories per day. Fifty-three patients between August 1, 2019, and August 26, 2020, met criteria for analysis; 60% (n = 32) used a dextrose and 40% (n = 21) used a nondextrose maintenance fluid. Baseline characteristics were similar between fluid groups except for body mass index (25.1 dextrose vs 27.5 kg/m2 nondextrose), sex (43.8% female vs 52.4% male), and severe malnutrition (46.9% vs 28.6%), respectively. Phosphorus (52.5 vs 50 mmol; P = 0.33) and magnesium (24 vs 22 g; P = 0.63) supplementation 48 h following nutrition initiation were similar between groups; however, potassium supplementation was lower in the dextrose group (165.0 vs 208.7 mEq; P = 0.01). No difference was observed between groups for time to discharge following nutrition initiation or time to goal kilocalories per day. After controlling for patients who were malnourished between fluid groups using linear regression, phosphorus repletion differences remained nonsignificant. This study did not detect a difference in phosphorus supplementation between groups, even after controlling for patients who were malnourished.