title: Microbial contamination of enteral feeding products in thermoneutral and hyperthermal ICU environments.
abstract: BACKGROUND
  Temperature is known to affect bacterial growth, but current safety recommendations for enteral formula are based on studies conducted in thermoneutral environments, which are not representative of select burn intensive care units (ICUs) that are kept therapeutically hyperthermal. This project evaluated microbial growth in 3 enteral feeding systems: closed, open, and open with modular additives (modular tube feeding [MTF]) exposed to 2 different environments.
  
  
  METHODS
  Product for each of the 3 systems was prepared and hung in both a thermoneutral (23.3°C) and a hyperthermal (32.5°C) ICU room. At baseline, 4 hours, and 8 hours, samples were plated and incubated overnight and the number of colony-forming units (CFUs) counted.
  
  
  RESULTS
  In the thermoneutral and hyperthermal environments, there was no evidence of microbial growth in the open or closed feeding systems at any time point. The MTF exhibited baseline contamination with a median of 10 CFUs (95% CI, 8-16) and significant growth over time to 54 CFUs (95% CI, 20-230) by 8 hours in the thermoneutral setting. In the hyperthermal environment, the MTF showed baseline contamination of 390 CFUs (95% CI, 40-1600) and significant growth over time, with 30% of samples exhibiting contamination levels exceeding Food and Drug Administration standards by 4 hours and CFUs being too numerous to count by 8 hours.
  
  
  CONCLUSIONS
  CFUs in enteral formula did not differ between open and closed feeding systems in either environment for up to 8 hours; however, the addition of modulars to open systems may result in an unacceptable risk of contamination in hyperthermal environments.
authors.affiliation: Military-Baylor Graduate Program in Nutrition, JBSA Fort Sam Houston, Texas Brooke Army Medical Center, San Antonio, Texas.
authors.forename: Jeffery
authors.initials: J
authors.lastname: Perry
authors.affiliation: Military-Baylor Graduate Program in Nutrition, JBSA Fort Sam Houston, Texas Brooke Army Medical Center, San Antonio, Texas susan.stankorb.mil@mail.mil.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Stankorb
authors.affiliation: Military-Baylor Graduate Program in Nutrition, JBSA Fort Sam Houston, Texas Brooke Army Medical Center, San Antonio, Texas.
authors.forename: Marybeth
authors.initials: M
authors.lastname: Salgueiro
mesh_terms: D015169:Colony Count, Microbial / Q000706:statistics & numerical data; D004750:Enteral Nutrition / Q000379:methods*; D005069:Evaluation Studies as Topic; D005506:Food Contamination / Q000032:analysis* / Q000706:statistics & numerical data; D005526:Food, Formulated / Q000382:microbiology*; D006801:Humans; D007362:Intensive Care Units; D013696:Temperature; D013997:Time Factors
keywords: burns; enteral formulas; enteral nutrition; food contamination; food safety; intensive care units; nutritional support