Hospital-acquired infections in critically-ill COVID-19 patients

Chest. 2021 Apr 12:S0012-3692(21)00679-6. doi: 10.1016/j.chest.2021.04.002. Online ahead of print.


BACKGROUND: Few small studies have described hospital-acquired infections (HAIs) during COVID-19.

RESEARCH QUESTION: What patient characteristics in critically ill patients with COVID-19 are associated with HAIs and how do HAIs associate with outcomes in these patients?

STUDY DESIGN AND METHODS: Multicenter retrospective analysis of prospectively collected data including adult patients with severe COVID-19, admitted to 8 Italian hub hospitals from February 20, 2020, to May 20, 2020. Descriptive statistics, univariable and multivariable Weibull regression models were used to assess incidence, microbial etiology, resistance patterns, risk factors (i.e., demographics, comorbidities, exposure to medication), and impact on outcomes (i.e., ICU survival, length of ICU and hospital stay and duration of mechanical ventilation) of microbiologically-confirmed HAIs.

RESULTS: Of the 774 included patients, 359 (46%) patients developed 759 HAIs (44.7 infections/1000 ICU patient-days, 35% multi-drug resistant (MDR) bacteria). Ventilator-associated pneumonia (VAP) (389, 50%), bloodstream infections (183, 34%), and catheter related blood stream infections (74, 10%) were the most frequent HAIs, with 26.0 (23.6-28.8) VAPs/1000 patient intubation-days, 11.7(10.1-13.5) BSIs/1000 ICU patient-days, and 4.7 (3.8-5.9) CRBSIs/1000 patient-days. Gram-negative bacteria (especially Enterobacterales) and Staphylococcus aureus caused 64% and 28% of VAPs. Variables independently associated with infection were age, PEEP and treatment with broad-spectrum antibiotic at admission. 234 patients (30%) died in ICU (15.3 deaths/1000 ICU patient-days). Patients with HAIs complicated by septic shock had almost doubled mortality (52% vs. 29%), while non-complicated infections did not affect mortality. HAIs prolonged mechanical ventilation (24(14-39) vs. 9(5-13) days; p<0.001), ICU and hospital stay (24(16-41) vs. 9(6-14) days, p=0.003; and (42(25-59) vs. 23(13-34) days, p<0.001).

INTERPRETATION: Critically-ill COVID-19 patients are at high risk for HAIs, especially VAPs and BSIs due to MDR organisms. HAIs prolong mechanical ventilation and hospitalization, and HAIs complicated by septic-shock almost doubled mortality.

PMID:33857475 | DOI:10.1016/j.chest.2021.04.002