Decanting versus sterile pre-filled nutrient containers ‐ the microbiological risks in enteral feeding

Abstract

A simulated ward study was carried out to compare the microbiological risk of assembling and running four different enteral feeding systems for 24 h. Assembly was carried out, (i) according to manufacturers' instructions with hands either covered by disposable gloves or deliberately contaminated with a test organism, or (ii) touching both the nutrient container top and pump set connector with hands deliberately contaminated with K. aerogenes. Two of the systems were ready-to-hang types (pack and bottle), the other two required feed to be decanted from either bottles or cans. When manufacturers' instructions were followed and disposable gloves worn, organisms were only detected in feeds decanted from cans and at levels < or = 20 cfu ml(-1). However, when systems were assembled following manufacturers' instructions, but with contaminated hands, no organisms were found in either of the ready-to-hang systems but average bacterial counts in samples from systems where the feed was decanted from bottles were 1.8 x 10(3) cfu ml(-1) at 24 h and 9.3 x 10(5) cfu ml(-1) for those where feed was decanted from cans. When systems were deliberately touched with contaminated hands, no organisms were detected in any feed samples from the pack system at 24 h, while bacterial counts for the other three systems ranged from 10(1) to 10(5) cfu ml(-1). The results highlight the important role played by system design in reducing both the level and incidence of bacterial contamination of enteral tube feeds and indicate that ready-to-hang feeding systems should be the preferred choice. However, if decanting of feeds cannot be avoided then strict adherence to manufacturers' instructions and the use of disposable gloves is to be advised.

A.S.P.E.N. Enteral Nutrition Practice Recommendations

“…16,23,45 In an early study of various administration sets that were deliberately contaminated, investigators found sterile, decanted formula to have low-to-no bacterial contamination for up to 12 hours when clean gloves were worn when adding the formula to the bag. 58 They also found that a recessed spike set allowed for limited exposure of the portto-touch contamination, regardless of the type of container used. Weenk and Kemen compared various feeding systems and found a sterile glass bottle containing enteral formula to be associated with the lowest level of microbial growth from touch contamination.…”

“…Many studies in the literature document the safety of a 24-hour hang time for sterile closed systems. 24,30,32,45,58 A few studies looking at hang times of 36 and 48 hours have reported little to no contamination. 24,58,59 One study even validated the safety of using a closed system enteral formula for intermittent bolus feeding in nursing home patients.…”

“…24,30,32,45,58 A few studies looking at hang times of 36 and 48 hours have reported little to no contamination. 24,58,59 One study even validated the safety of using a closed system enteral formula for intermittent bolus feeding in nursing home patients. 47 Much research has focused on contamination of enteral administration sets with investigators trying to discern if the source of bacterial growth is from healthcare providers' hands vs endogenous retrograde growth from the patient.…”

“…A study published by Beattie and Anderson in 2001 demonstrated a reduction in microbial contamination of EN formula when manufacturer's recommendations were followed (using deliberately contaminated hands) and faulty handling. 58 Four types of containers and spike sets were studied and results showed using disposable gloves and following manufacturer's instructions when pouring decanted formula into a bag did result in acceptable lowto-no microbial contamination. In summary, all of these studies validate the safety of formulas in clinical practice and advocate strict adherence to standard precautions and manufacturer's recommendations when handling formula that is decanted.…”

“…The most serious complication has been bowel necrosis in a total of 32 patients. 58 Melis et al's review of the literature indicated that distention and sepsis or worsening general condition should prompt evaluation and discontinuation of the feedings. 58 Several studies of feeding after PEG placements in adults have been published.…”