Low incidence of arterial catheter infections in a Swedish intensive care unit: risk factors for colonisation and infection

SummaryThere is growing concern that arterial catheters (ACs) cause catheter-related infections (CRIs). Limited data are available concerning risk factors for AC-CRI and there are no studies concerning incidence and micro-organisms from northern Europe. The aims of this study were to determine the incidence of, and micro-organisms responsible for, AC colonisation and AC-CRI in a Swedish intensive care unit (ICU), and to determine risk factors contributing to AC colonisation and AC-CRI. We prospectively studied all patients (N = 539) receiving ACs (N = 691) in a mixed ICU of a county hospital. Six hundred (87%) of all ACs were assessed completely. The total catheterisation time for 482 patients was 2567 days. The incidence of positive tip culture was 7.8 per 1000 catheter-days, with the predominant micro-organism being coagulase-negative staphylococci (CoNS). The incidence of AC-CRI was 2.0 per 1000 catheter-days (with no cases of bacteraemia). All AC-CRIs were caused by CoNS. Multivariate analysis revealed that immunosuppression, central venous catheter (CVC) colonisation and CVC infection were significant risk factors for AC-CRI. We conclude that AC colonisation and infection with systemic symptoms occur at a low rate in our ICU which supports our practice of basic hygiene routines for the prevention of AC-CRI. Colonisation and infection of a simultaneous CVC seem to be risk factors. The role of contemporaneous colonisation and infection of multiple bloodstream catheters has received little attention previously. Further studies are needed to verify the significance of this finding.