Nasogastric feeding tubes from a neonatal department yield high concentrations of potentially pathogenic bacteria—even 1 d after insertion

Background:
Preterm infants are vulnerable to pathogens and at risk of developing necrotizing enterocolitis (NEC) or sepsis. Nasogastric feeding tubes (NG-tubes) might contaminate feeds given through them due to biofilm formation. We wanted to determine if there is a rationale in replacing NG-tubes more often to reduce contamination.

Methods:
We conducted an observational study of used NG-tubes from a tertiary neonatal department. After removal, we flushed a 1-ml saline solution through the tube, determined the density of bacteria by culture, and related it to the duration of use and any probiotic administration through the tube.

Results:
Out of the 94 NG-tubes, 89% yielded more than 1,000 colony-forming units (CFU)/ml bacteria, and 55% yielded the potentially pathogenic Enterobacteriaceae and/or Staphylococcus aureus. The mean concentration in the yield was 5.3 (SD: 2.1, maximum 9.4) log10CFU/ml. Neither the presence of contamination nor the density was associated with the time the NG-tube had been in use. Probiotic administration did not protect against contamination.

Conclusion:
NG-tubes yielded high densities of bacteria even within the first day of use. Further studies are needed to determine if changing the NG-tubes between meals or once a day will make a positive impact on tube contamination and clinical parameters.