Objective: To determine the effect of routine intravascular administration-set changes on central venous catheter (CVC) colonization and catheter related bacteremia (CRB). Design: Prospective, randomised controlled trial Setting: 18-bed ICU in a University-affiliated, tertiary referral hospital. Participants: 404 chlorhexidine and silver sulfadiazine coated multi-lumen CVCs from 251 intensive care unit (ICU) patients. Interventions: After ethical approval, CVCs inserted in ICU and in situ on Day 4 were randomised to have their administration-sets changed on Day 4 (n = 203) or not at all (n = 201). Fluid container and blood product administration-set use was limited to 24 hours. CVCs were removed (Day 7, not required or suspected infection), and cultured for colonization ( 15 cfu). Medical and laboratory staff were blinded. CRB was diagnosed by a blinded intensivist using strict definitions. Data was collected on; catheter life, CVC site, APACHE II score, patient age, diagnosis, hyperglycemia, hypoalbuminemia, immune status, number of fluid containers and intravenous injections, propofol, blood, TPN or lipid infusion. Results: There were 10 colonized CVCs in the set change group and 19 in the no change group. This was not a statistically significant difference on Kaplan Meier survival analysis (Effect Size = 0.09, Log Rank = 0.87, df = 1, p = 0.35). There were 3 cases of CRB per group. Logistic regression found that burns diagnosis and increased ICU stay were the only factors that significantly predicted colonization (p < 0.001). Conclusions: Intravenous administration-sets can be used for 7-days. Routine administration-set changes are unnecessary before this time
