Renal formulas pretreated with medications alters the nutrient profile

Abstract

Background Pretreating renal formulas with medications to lower the potassium and phosphorus content is common in clinical practice; however, the effect of this treatment on other nutrients is relatively unstudied. We examine whether nutrient composition is affected by pretreating renal formulas with sodium polystyrene sulfonate (SPS) suspension and sevelamer carbonate. Methods Fixed medication doses and treatment times were utilized to determine changes in the nutrient composition of Suplena® and Similac® PM 60/40. The effect of simultaneously adding both medications (co-administration) to the formula on the nutrient composition of Suplena® was also evaluated. Results Pretreatment of Suplena® with SPS reduced the concentrations of calcium (11–38 %), copper (3–11 %), manganese (3–16 %), phosphorus (0–7 %), potassium (6–34 %), and zinc (5–20 %) and increased those of iron (9–34 %), sodium (89–260 %), and sulfur (19–45 %) and the pH (0.20–0.50 units). Pretreatment of Similac® PM 60/40 with SPS reduced the concentrations of calcium (8–29 %), copper (5–19 %), magnesium (3–26 %), and potassium (33–63 %) and increased those of iron (13–87 %) and sodium (86–247 %) and the pH (0.40–0.81 units). Pretreatment of both formulas with the SPS suspension led to significant increases in the aluminum concentration in both formulas (507–3957 %). No differences in potassium concentration were observed between treatment times. Unexpectedly, the levels of neither phosphorus nor potassium were effectively reduced in Suplena® pretreated with sevelamer carbonate alone or when co-administered with SPS. Conclusions Pretreating formula with medications alters nutrients other than the intended target(s). Future studies should be aimed at predicting the loss of these nutrients or identifying alternative methods for managing serum potassium and phosphorus levels in formula-fed infants. The safety of pretreating formula with SPS suspension should also be examined.

Pretreatment of enteral nutrition with sodium polystyrene sulfonate: effective, but beware the high prevalence of electrolyte derangements in clinical practice

“…Several prior in vitro studies evaluating pretreatment of EN with SPS have shown significant reductions in the formula content of potassium (6–89%) and concomitant increases in the sodium content (86–527%) [ 3–9 ]. Most in vitro studies have also demonstrated reductions in formula calcium content (8–84%); however, conflicting information is available regarding the effect of pretreatment of formula on magnesium and phosphorus content [ 3 , 5 , 6 , 9 ]. Discrepancies reported in the in vitro studies are likely due to variations in preparation techniques and dosing.…”

“…Notably, they also reported a significant reduction in serum calcium levels (10.7 versus 10.0 mg/dL; P = 0.014) with no significant change in serum sodium or magnesium levels. The authors denied any clinically noticeable side effects but did note that, in their experience, many infants require calcium and magnesium supplementation when receiving SPS-treated EN [ 9 ]. Although, the five patients described by Bunchman et al .…”

“…Several in vitro studies using various doses of SPS have shown 6–89% reductions in the potassium content of various types of formula or EBM [ 2–9 ]. In addition, changes in formula content of other electrolytes, such as increases in sodium [ 3–9 ] as well as decreases in calcium [ 3 , 5 , 6 , 9 ] and magnesium [ 3 , 6 , 9 ], have also been observed. Although there are several reports of the in vitro effects of pretreating EBM or formula with SPS, there are limited patient safety and efficacy data.…”

Optimizing Enteral Nutrition for Growth in Pediatric Chronic Kidney Disease (CKD)

“…Modulars, discussed below, can increase caloric density if needed. The clinician should do their best to work breastmilk into the feeding regimen, not wasting any of the typically hard-earned liquid, if the mother is willing and able to provide any, even for the short-term (36). …”

“…This make it difficult to know what nutrients the individual is receiving and whether micronutrient inadequacy or excess may be occurring. Additionally, use of a liquid suspension greatly increases aluminum content of the formula (36). Thus, if this product is used, the powdered version should be chosen.…”