Colonization of oropharynx and lower respiratory tract in critical patients: Risk of ventilator-associated pneumonia.

OBJECTIVE: To investigate the microbial diversity existing in oral cavity and respiratory tract samples (from mini-bronchoalveolar lavage (BAL), endotracheal aspirate, and orotracheal tube) of patients on mechanical ventilation by using the checkerboard DNA-DNA hybridisation. Also, the study aimed to evaluate whether the microbial profile in the oral cavity is found in respiratory tract samples, at different periods of mechanical ventilation time (12h, 48h, 96h) in attempt to identification of relationship between VAP (ventilator-associated pneumonia) and bacterial species studied. The last objective was to analyses correlation between blood cultures and VAP. DESIGN: The samples were collected from ten patients in intensive care unit with medical prescription of orotracheal intubation and mechanical ventilation. Clinical data were tabulated and blood cultures were performed according medical indication. For checkerboard samples collection, chosen sites were the dorsal side of the tongue and gingival sulcus at 12h, 48h, 96h, BAL, at 12h, endotracheal aspirate at 48 and 96h, and orotracheal tube at extubation time, when feasible. RESULTS: It was possible to identify the presence of bacterial species in mouth and in the BAL/endotracheal aspirate. The data demonstrated an increase in the quantity of bacterial associated with prolonged use of mechanical ventilation (48 and 96h). CONCLUSIONS: Bacterial species may migrate rapidly from mouth and upper airways during orotracheal intubation which contributes to the pathogenesis of VAP. There were associations between VAP and Enterococcus faecalis, Fusobacterium periodonticum, Gemella morbillorum, Neisseria mucosa, Propionibacterium acnes, Prevotella melaninogenica, Streptococcus oralis, Streptococcus sanguinis, Treponema denticola, Treponema socransckii, and Veillonella parvula.

Klebsiella pneumoniae Planktonic and Biofilm Reduction by Different Plant Extracts: In Vitro Study.

This study evaluated the action of Pfaffia paniculata K., Juglans regia L., and Rosmarius officinalis L. extracts against planktonic form and biofilm of Klebsiella pneumoniae (ATCC 4352). Minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC) values were determined for each extract by microdilution broth method, according to Clinical and Laboratory Standards Institute. Next, antimicrobial activity of the extracts on biofilm was analyzed. For this, standardized suspension at 107 UFC/mL of K. pneumoniae was distributed into 96-well microplates (n = 10) and after 48 h at 37°C and biofilm was subjected to treatment for 5 min with the extracts at a concentration of 200 mg/mL. ANOVA and Tukey tests (5%) were used to verify statistical significant reduction (p < 0.05) of planktonic form and biofilm. P paniculata K., R. officinalis L., and J. regia L. showed reductions in biomass of 55.6, 58.1, and 18.65% and cell viability reduction of 72.4, 65.1, and 31.5%, respectively. The reduction obtained with P. paniculata and R. officinalis extracts was similar to the reduction obtained with chlorhexidine digluconate 2%. In conclusion, all extracts have microbicidal action on the planktonic form but only P. paniculata K. and R. officinalis L. were effective against biofilm.