Background: The potential relationship between intravascular catheter infections with their insertion during weekend or night-time (i.e., off-hours or not regular business hours) remains an open issue. Our primary aim was to describe differences between patients and catheters inserted during on- versus off-hours. Our secondary aim was to investigate whether insertions during off-hours influenced the intravascular catheter infectious risks.

Methods: We performed a post hoc analysis using the databases from four large randomized-controlled trials. Adult patients were recruited in French ICUs as soon as they required central venous catheters or peripheral arterial (AC) catheter insertion. Off-hours started at 6 P.M. until 8:30 A.M. during the week; at weekend, we defined off-hours from 1 P.M. on Saturday to 8.30 A.M. on Monday. We performed multivariable marginal Cox models to estimate the effect of off-hours (versus on-hours) on major catheter-related infections (MCRI) and catheter-related bloodstream infections (CRBSIs).

Results: We included 7241 patients in 25 different ICUs, and 15,208 catheters, including 7226 and 7982 catheters inserted during off- and on-hours, respectively. Catheters inserted during off-hours were removed after 4 days (IQR 2, 9) in median, whereas catheters inserted during on-hours remained in place for 6 days (IQR 3,10; p < 0.01) in median. Femoral insertion was more frequent during off-hours. Among central venous catheters and after adjusting for well-known risk factors for intravascular catheter infection, we found a similar risk between off- and on-hours for MCRI (HR 0.91, 95% CI 0.61-1.37, p = 0.65) and CRBSI (HR 1.05, 95% CI 0.65-1.68, p = 0.85). Among central venous catheters with a dwell-time > 4 or > 6 days, we found a similar risk for MCRI and CRBSI between off- and on-hours. Similar results were observed for ACs.

Conclusions: Off-hours did not increase the risk of intravascular catheter infections compared to on-hours. Off-hours insertion is not a sufficient reason for early catheter removal, even if femoral route has been selected.