Bronchoscopy in critically ill COVID-19 Patients: microbiological profile and factors related to nosocomial respiratory infection

Background Nosocomial co-infections are a cause of morbidity and mortality in Intensive Care Units (ICU). Objectives Our aim was to describe bronchoscopy findings and analyse co-infection through bronchial aspirate (BA) samples in patients with COVID-19 pneumonia requiring ICU admission. Methods We conducted a retrospective observational study, analysing the BA samples collected from intubated patients with COVID-19 to diagnose nosocomial respiratory infection. Results One-hundred and fifty-five consecutive BA samples were collected from 75 patients. Of them, 90 (58%) were positive cultures for different microorganisms, 11 (7.1%) were polymicrobial, and 37 (23.7%) contained resistant microorganisms. There was a statistically significant association between increased days of orotracheal intubation (OTI) and positive BA (18.9 days versus 10.9 days, p<0.01), polymicrobial infection (22.11 versus 13.54, p<0.01) and isolation of resistant microorganisms (18.88 versus 10.94, p<0.01). In 88% of the cases a change in antibiotic treatment was made. Conclusion Nosocomial respiratory infection in intubated COVID-19 patients seems to be higher than in non-epidemic periods. The longer the intubation period, the greater the probability of co-infection, isolation of resistant microorganisms and polymicrobial infection. Microbiological sampling through BA is an essential tool to manage these patients appropriately.