Exactly how long can we leave enteral formulas (ready-to-feed) hang while families rest?  Probably 12 hours according to a recent article (Nutr Clin Pract 2011; 26: 451).  This prospective study involving 30 pediatric patients studied the outcomes in those who received continuous enteral feedings using decanted formula for a minimum of 12 hours.  In this study, patients received both polymeric and peptide based formulas.  Cultures of the formula were obtained.  Among 111 usable cultures, 100 showed no growth, 6 had growth considered below FDA threshold for contamination & 5 (in two patients) had coliforms identified.  No patient developed clinical symptoms.  In these two patients, the authors speculate that contamination occurred due to a combination of exogenous source (touching) as well as possible endogenous source (retrograde movement of bacteria from patient’s gastrointestinal tract).

This small study lends support to extended hang times of up to 12 hours as long as the feeding sets are carefully managed with aseptic technique, clean gloves & avoiding touching formula.  Instead of more frequent changes to formula, this approach can allow parents to sleep while their children receive enteral nutrition and for nurses to pursue other activities for hospitalized patients.

The context for the study was a FDA recommendation for an 8-hour hang time based on conservative recommendations from manufacturers.  The FDA recommendation may have been influenced by a report in 2001 of an enteral powdered formula contaminated with Enterobacter sakazakii which lead to the death of a premature infant.

It should be noted that ready-to-feed enteral formulas are commercially sterilized prior to hanging whereas powdered formulas cannot be commercially sterilized.

Additional references:

• -MMWR 2002; 51: 297-300.
• -J Hosp Infect 2005; 59: 311-316.