Biodynamics of biofilm formation on nasogastric tubes in elderly patients

Background: We previously reported on the high propensity of pathogenic oral flora in the oropharynx of nasogastric tubefed patients, and subsequently showed biofilm formation on the NGTs of these patients. There is a close relationship of biofilm and oropharyngeal colonization with pathogenic bacteria, aspiration pneumonia and antibiotic resistance. Objectives: To investigate the time relation between the insertion of a new NGT and formation of the biofilm. Methods: We examined sequential samples on NGTs that were forcibly pulled out by the patients themselves during any of the 7 days after insertion. Scanning electron micrography and confocal laser scanning microscopy were used for biofilm detection. Results: Biofilm was identified on 60% of the five samples of day 1 and on all the samples of the following days, by both microscopic methods. Conclusions: Biofilms form within a single day on most NGTs inserted for the feeding of elderly patients with dysphagia. Further research should be devoted to prevention of biofilm formation on NGTs.