Respiratory pathogen colonization of dental plaque, the lower airways, and endotracheal tube biofilms during mechanical ventilation.
In mechanically ventilated patients, the endotracheal tube is an essential interface between the patient and ventilator, but inadvertently, it also facilitates the development of ventilator-associated pneumonia (VAP) by subverting pulmonary host defenses. A number of investigations suggest that bacteria colonizing the oral cavity may be important in the etiology of VAP. The present study evaluated microbial changes that occurred in dental plaque and lower airways of 107 critically ill mechanically ventilated patients.



Dental plaque and lower airways fluid was collected during the course of mechanical ventilation, with additional samples of dental plaque obtained during the entirety of patients' hospital stay.



A "microbial shift" occurred in dental plaque, with colonization by potential VAP pathogens, namely, Staphylococcus aureus and Pseudomonas aeruginosa in 35 patients. Post-extubation analyses revealed that 70% and 55% of patients whose dental plaque included S aureus and P aeruginosa, respectively, reverted back to having a predominantly normal oral microbiota. Respiratory pathogens were also isolated from the lower airways and within the endotracheal tube biofilms.



To the best of our knowledge, this is the largest study to date exploring oral microbial changes during both mechanical ventilation and after recovery from critical illness. Based on these findings, it was apparent that during mechanical ventilation, dental plaque represents a source of potential VAP pathogens.
Oral and Biomedical Sciences, School of Dentistry, Cardiff University, Cardiff, Wales, UK. Electronic address: Sandsk1@cf.ac.uk.
Kirsty M
KM
Sands
Oral and Biomedical Sciences, School of Dentistry, Cardiff University, Cardiff, Wales, UK.
Melanie J
MJ
Wilson
Oral and Biomedical Sciences, School of Dentistry, Cardiff University, Cardiff, Wales, UK.
Michael A O
MAO
Lewis
Adult Critical Care, University Hospital of Wales, Heath Park, Cardiff, Wales, UK.
Matt P
MP
Wise
Adult Critical Care, University Hospital of Wales, Heath Park, Cardiff, Wales, UK.
Nicki
N
Palmer
Bioimaging Hub, School of Biosciences, Cardiff University, Cardiff, Wales, UK.
Anthony J
AJ
Hayes
Cardiff Institute of Infection & Immunity, School of Medicine, Heath Park, Cardiff, Wales, UK.
Rosemary A
RA
Barnes
Oral and Biomedical Sciences, School of Dentistry, Cardiff University, Cardiff, Wales, UK.
David W
DW
Williams
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001419:Bacteria / Q000235:genetics; D018441:Biofilms; D002353:Carrier State / Q000382:microbiology*; D016638:Critical Illness; D004269:DNA, Bacterial / Q000032:analysis; D003773:Dental Plaque / Q000382:microbiology*; D005260:Female; D006801:Humans; D007442:Intubation, Intratracheal / Q000295:instrumentation*; D008168:Lung / Q000382:microbiology*; D008297:Male; D064307:Microbiota / Q000235:genetics*; D008875:Middle Aged; D053717:Pneumonia, Ventilator-Associated / Q000382:microbiology; D011550:Pseudomonas aeruginosa / Q000235:genetics; D012121:Respiration, Artificial; D013211:Staphylococcus aureus / Q000235:genetics; D012122:Ventilators, Mechanical; D055815:Young Adult
D004269:DNA, Bacterial
Endotracheal tube; Mechanical ventilation; Pseudomonas aeruginosa; Staphylococcus aureus; Ventilator-associated pneumonia