No association between ultrasound-guided insertion of central venous catheters and bloodstream infection: a prospective observational study.

BACKGROUND: Ultrasound guidance for the insertion of central venous catheters (CVCs) reduces mechanical complications and shortens insertion time, but its effect on CVC-associated bloodstream infection (CABSI) remains controversial.

AIM: To test the effect of ultrasound-guided CVC insertion on CABSI in a hospital-wide setting.

METHODS: A four-year prospective cohort study was conducted at a university-affiliated, tertiary care centre. All patients receiving a non-tunnelled CVC, inserted by an anaesthetist, were enrolled. Catheter surveillance was performed by trained infection control nurses and checked by an infection control doctor. The primary outcome was CABSI as defined by the US Centers for Disease Control and Prevention. The secondary outcome was all-cause mortality up to 28 days after CVC removal.

FINDINGS: In total, 2312 patients with 2483 CVCs were included and analysed. Ultrasound guidance was used for 844 CVC insertions (34.0%), with a significant increasing trend over the study period [incidence rate ratio 1.13, 95% confidence interval (CI) 01.11-1.15; P < 0.001]. Forty-seven CABSIs were identified, representing an overall incidence of 2.1 episodes per 1000 catheter-days. No association was detected between ultrasound guidance and CABSI (hazard ratio 0.69, 95% CI 0.36-1.30; P = 0.252). All-cause mortality was 11.0% (253/2312), with no significant trend and no association with ultrasound guidance.

CONCLUSION: Ultrasound guidance had no effect on CABSI or mortality. In a hospital-wide setting with baseline CABSI rates at the standard level currently found in high-income countries, the use of ultrasound has no additional benefit for the prevention of CABSI.