Comparison of bacterial contamination of blood conservation system and stopcock system arterial sampling lines used in critically ill patients.

Background: Commonly placed to monitor blood pressure and to aspirate blood, arterial lines frequently cause complications. The blood conservation system (BCS) forms a closed infusion line and may be expected to reduce complications caused by intraluminal contamination. We compared microbial contamination resulting from use of BCS and 3-way stopcock catheterization.

Methods: Patients who required arterial catheterization for at least 24 hours in our intensive care unit were randomly assigned to receive an arterial pressure monitoring system either with the BCS (test group) or with a 3-way stopcock (comparator group). To evaluate arterial line contamination, we qualitatively assessed the contamination of the catheter tip and intraluminal fluid.

Results: We analyzed microbial contamination for a total of 216 arterial catheters: 109 in the test group and 107 in the comparator group. We found no difference in the incidence of catheter tip colonization in the 2 groups (test group, 8/109 vs comparator group, 11/107; P = .48). There was a statistically significant correlation between catheter tip colonization and duration of arterial line utilization. We found statistically significantly lower intraluminal fluid contamination in the test group (test group, 2/109 vs comparator group, 9/107; P = .03). There was no relationship between intraluminal fluid contamination and catheter tip contamination.

Conclusion: There was less microbial contamination of intraluminal fluid when BCS was used for arterial catheterization.