BackgroundProne positioning (PP) is a standard of care for patients with moderate–severe acute respiratory distress syndrome (ARDS). While adverse events associated with PP are well-documented in the literature, research examining the effect of PP on the risk of infectious complications of intravascular catheters is lacking.MethodAll consecutive ARDS patients treated with PP were recruited retrospectively over a two-year period and formed the exposed group. Intensive care unit (ICU) patients during the same period without ARDS for whom PP was not conducted but who had an equivalent disease severity were matched 1:1 to the exposed group based on age, sex, centre, length of ICU stay and SAPS II (unexposed group). Infection-related catheter complications were defined by a composite criterion, including catheter tip colonization or intravascular catheter-related infection.ResultsA total of 101 exposed patients were included in the study. Most had direct ARDS (pneumonia). The median [Q1–Q3] PP session number was 2 [1–4]. These patients were matched with 101 unexposed patients. The mortality rates of the exposed and unexposed groups were 31 and 30%, respectively. The incidence of the composite criterion was 14.2/1000 in the exposed group compared with 8.2/1000 days in the control group (p = 0.09). Multivariate analysis identified PP as a factor related to catheter colonization or infection (p = 0.04).ConclusionOur data suggest that PP is associated with a higher risk of CVC infectious complications.