NICU Feeding Tube Guidelines to Reduce Bacterial Contamination

How often should feeding tubes be changed, and what can be done to minimize bacterial contamination?

The short answer is there is no definitive answer, other than “manufacturer recommendations,” which typically say PVC tubes are to be changed every 3 days and polyurethane (“poly”) and silicone should be changed every 30 days. Although these are manufacturer recommendations, there is research to show that feeding tubes are a likely source of bacterial contamination.

Not only have feeding tubes been known to cause infections in a patient, but there is additional research showing contamination between patients. The same strain has been found in multiple infants within the same NICU.^1,2 This is most likely from inadvertent cross contamination by nurses.

In one study done over a period of 2.5 weeks, 125 feeding tubes were cultured from a total of 50 babies.  Of these 125 tubes, only 8 showed no contamination. Greater than 90% of the feeding tubes that were cultured were positive for bacteria. The infants that had contaminated feeding tubes were more likely to show signs of feeding intolerance, decreased weight gain, and necrotizing enterocolitis (NEC).^2,3

In a separate study, infants fed formula through contaminated feeding tubes had feeding intolerance. In that same study, infants who were fed breast milk, whether the tube was contaminated or not, showed no feeding intolerance.

Unlike the interval of feedings in adults, the very frequent feedings that a neonate receives can cause a sustained increase in pH. A higher pH offers a greater chance for bacteria to survive, colonization to happen, and infections to develop.^2,4 The likelihood of feeding tubes becoming colonized even after six hours is high.⁵ This can be due to contamination during tube insertion, a contaminated feeding, retrograde or reflux of gastric contents into the tube (shown in 85% of feeding systems in the NICU),⁷ or bacteria that “break off” from the inner diameter of the feeding tube with subsequent feedings and enter the stomach as a bolus with each feed. ⁴

Although placing feeding tubes is a very frequent occurrence in the NICU as the majority of patients admitted require one, it is not without risk. Research has shown that placing a feeding tube alters cerebral blood flow and is a stressful/painful procedure for an infant.⁴

What are some things that can be done to decrease the risk of contamination without the obvious stress of placing a feeding tube with each feed?

1. Change feeding tubes more frequently. A study done at RUSH university showed that NEC rates significantly decreased when feeding tubes were changed Q7D and extension sets were changed QF.⁷
2. Ensure aseptic technique when placing a feeding tube to decrease risk of nosocomial contamination.⁹
3. Nurses should always wear gloves when handling feedings and/or feeding tubes.⁹
4. Do not store reconstituted feedings in the refrigerator for greater than 24 hours.^8,9,10
5. The time a feeding is left at room temperature should be minimized to avoid bacterial overgrowth.
6. Offer breast milk whenever possible – it offers immunoprotective properties.³
7. The FDA and CDC recommend using ready-to-feed, sterile liquid formulas/additives whenever possible to avoid risk of contamination from non-sterile, multi-use powdered formulas.^7,8,9

Infections in the NICU are incredibly taxing across a spectrum – parents have to deal with the stress of the unknowns related to their child being sick, while nurses wonder “What did I do? Could it be my fault?” or “Did I miss something?” The care team struggles to ensure they have a significantly reactive plan in place in order to decrease the morbidity(ies) associated with infections, and the potential cost to the healthcare provider (insurance, hospital, etc.) is extremely high.

Although placing feeding tubes is a routine occurrence in the NICU, let us not take for granted the potential risks that can be associated with placing these tubes. Instead, let us be very diligent and mindful about the risks associated with placing tubes, and do what we can to minimize the risk of contamination.

 

References:

1. Mehall, J., Kite, C., Gilliam, C., Jackson, R., and Smith, S. Enteral Feeding Tubes Are a Reservoir for Nosocomial Antibiotic-Resistant Pathogens.  Journal of Pediatric Surgery, 2002; 37(8);1177-1182.
2. Juma, N. and Forsythe, S. Microbial Biofilm Development on Neonatal Enteral Feeding Tubes.  Advnaces in Experimental Medicine and Biology, 2015;1:113-121.  doi:10.1007/978-3-319-11038-7_7
3. Mehall, J., Kite, C., Saltzman, D., Wallett, T., Jackson, R. and Smith, S. Prospective Study of the Incidence and Complications of Bacterial Contamination of Enteral Feeding in Neonates.  Journal of Pediatric Surgery, 2002; 37(8);1177-1182.
4. Wallace, T. and Steward, D. Gastric Tube Use and Care in NICU.  Newborn and Infant Nursing Reviews, 2014; 14(3);103-108.
5. Hurrell, E. et al. Neonatal enteral feeding tubes as loci for colonization by members of the Enterobacteriaceae.  BMC Infectious Diseases, 2009; 9(146).  doi:10.1186/1471-2334-9-146
6. Petersen, S., Greisen, G. and Krogfelt, K. Nasogastric feeding tubes from a neonatal department yield high concentrations of potentially pathogenic bacteria – even 1 d after insertion.  Pediatric Research, 2016;80(3);395-400.
7. Patel, AL. et al. Reducing necrotizing enterocolitis in very low birth weight infants using quality-improvement methods.  Journal of Perinatology, 2014; 34;850–857.
8. Matlow, A. et al. Enteral tube hub as a reservoir for transmissible enteric bacteria.  American Journal of Infection Control, 2006;34(3);131-133.  doi:10.1016/j.ajic.2005.10.005
9. The American Society of Parenteral and Enteral Nutrition (2009). Enteral Nutrition Practice Recommendations. ASPEN: Silver Sring, MD
10. The Human Milk Banking Association of North America, Inc. (2011).   Best Practice for Expressing, Storing and Handling Human Milk in Hospitals, Homes and Child Care Settings. HMBANA: West Hartford, CT.