Ventilator-associated pneumonia risk factors in patients with severe COVID-19 in southern Brazil: A retrospective observational study.

Backgound: During the SARS-CoV-2 pandemic, a significant number of critical patients required ventilatory assistance in health institutions. In this context, Ventilator-Associated Pneumonia (VAP) was the most prevalent nosocomial infection among critically ill patients. We aimed to analyze the occurrence of VAP in critically ill patients with SARS-CoV-2 and the risk factors associated with the outcome.

Method: This is a multicenter, retrospective cohort study which included patients ≥18 years old, diagnosed with COVID-19, admitted to intensive care units (ICU) and who received invasive mechanical ventilation (MV) for >2 consecutive days. The associations between the variables were initially tested, and those that showed potential associations (p<0.05) were included in the multivariate logistic regression model.

Results: One third of patients had an episode of VAP, with an incidence density of 34.97 cases per 1000 MV days. In addition, 42.37% (50) of the microorganisms causing VAP were multidrug-resistant, predominantly gram-negative bacteria (61.32%). More than 50% of participants developed healthcare-associated infections and 243 (73.64%) died. The factors associated with greater chances of VAP were: prone position (OR= 3.77), BMI 25-29.9 kg/m² (OR= 4.76), pressure injury (OR= 4.41), length of stay in the ICU (OR= 1.06), positive tracheal aspirate before VAP (OR= 5.41) and dyspnea (OR= 3.80).

Conclusions: Patients with COVID-19 are at high risk of VAP, which leads to an increased risk of death (OR = 2.18). Multiple factors increase the chances of VAP in this population, namely: work overload in health institutions, prone position, prolonged ICU time, infusion of multiple drugs, invasive devices, and in particular, immobility in bed.