Update on osmolality of oral medications and enteral nutrition used in neonatal department

Introduction
Necrotizing enterocolitis (NEC) is the most common acquired disease of gastrointestinal tract in preterm infants and is unfortunately the leading cause of death. [1] As the osmolality of enteral solutions is one of the risk factors identified in the occurrence of NEC, the American Academy of Pediatrics (AAP) recommends that infant formulas should not exceed an osmolality of 450 mOsm/kg [1,2]. The objectives of this work were to: (1) perform an inventory of the osmolality of all infant formulas and all drugs (specialities and magistral and hospital preparations) administrated to preterm neonates in our hospital and (2) to propose to prescribers a theoretical osmolality calculator for all enteral administration.

Materials and methods
Infant formulas and drugs (specialities and preparations) were identified from an extraction of consumption of the neonatal department in 2021. Infant formulas were prepared in nursery in the usual way. Solid forms were dissolved in 10 mL of water for injection. Osmolalities were measured by an osmometer (Model 2020, Advanced Instrument). Theorical osmolality calculator was designed in an Excel file.

Results and discussion
92 osmolalities were measured (16 infant formulas and 75 medications). 59,3 % of the samples met AAP’s recommendations : 100% of the infant milks and 49,3% of medications had an osmolality < 450 mOsm/kg. 86,4% of solid oral forms had osmolality < 450 mOsm/kg and 34,0 % of liquid oral forms. Liquids specialities had the highest osmolality, two of which were > 10 000 mOsm/kg, due to the presence of alcohol or polyethylene glycol. 78,0 % of drug specialities need dilution before administration in order to met AAP’s recommendations. Preparations had lower osmolalities than specialities : 70,0% had an osmolality < 450 mOsm/kg. One of the pre-formulated vehicle used in our pharmacotechnie unit was hyperosmolar (> 1200 mOsm/kg). Data collected allow us to create a theorical osmolality calculator for combined mixtures, integrating 75 medications or preparations and 22 different diluents (16 milks and 5 solutes).

Discussion and conclusion
Osmolality measurement is not part of the monograph of oral forms of the European Pharmacopoeia, however considering the high risk of complications it would be interesting to measure it before the implementation of any new drug in the neonatology department. This calculator will allow to estimate osmolality of enteral treatments in neonatalogy. The next step will be to evaluate its clinical impact on the occurrence of NEC.

Références bibliographiques :
1. Lueschow SR et al. . Nutrients 2020; 12: 900.
2. Chen Y et al. Dis. Model. Mech. 2019; : dmm.040998.
Watch the video in simultaneous translation

Watch the video in simultaneous translation