Oral microbiome of patients in intensive care unit: literature review

Abstract

Knowledge of the most prevalent microorganisms and their control protocols are fundamental for the comprehensive care of patients in intensive care. The objective of this work was to determine the main pathogens that make up the oral microbiome of intensive care patients. A literature review was carried out in the Pubmed and Scielo databases. The descriptors used were “nosocomial pneumonia” AND “oral cavity” and “oral microbiome” AND “ICU”. Articles published in the last 10 years were included. Gray literature was excluded. After applying the criteria, 7 articles were selected for this review. More than 500 types of bacteria have been described in the oral cavity, with approximately 22 classified as dominant. Among the main bacteria, the following stand out: Pseudomonas aeruginosa, S. aureus, Acinetobacter spp, Klebsiella spp, Enterobacter spp, S. pneumoniae, E. coli, Klebsiella pneumoniae and Enterococcus faecalis. Species variations are found between dentate and edentulous patients. Microbiological coincidence is high between dental biofilm and lower airways. Other microorganisms may be present in the oral microbiome, such as Redondoviridae, associated with both periodontitis and respiratory failure, and Candida albicans. In view of the diversity of pathogens, the cleaning agent must have a broad spectrum, with few side effects for the patient. The literature shows that the most common oral pathogens in critically ill patients are gram-negative bacteria and Staphylococcus aureus. Chlorhexidine digluconate 0.12% has proven to be the gold standard for cleaning the oral cavity in patients in these environments, due to its broad spectrum and substantivity.