Bacteremia related with arterial catheter in critically ill patients

Catheter-related bloodstream infections (CR-BSI) are an increasing problem in the management of critically ill patients. Our objective was to analyze the incidence and epidemiology of CR-BSI in arterial catheters (AC) in a population of critically ill patients.

We conducted a two-year, prospective, non-randomized study of patients admitted for > 24 h in a 24-bed medical-surgical major teaching ICU. We analyzed the arterial catheters and differentiated between femoral and radial locations. Difference testing between groups was performed using the two-tailed t-test and chi-square test as appropriate. Multivariate logistic regression analyses were conducted to identify independent predictors of CR-BSI occurrence and type of micro-organism responsible.

The study included 1456 patients requiring AC placement for ≥ 24 h. A total of 1543 AC were inserted for 14,437 catheter days. The incidence of AC-related bloodstream infections (ACR-BSI) was 3.53 episodes per 1000 catheter days. In the same period the incidence of central venous catheter (CVC)-related bloodstream infections was 4.98 episodes per 1000 catheter days. Logistic regression analysis showed that days of insertion (OR: 1.118 95% confidence interval (CI) 1.026-1.219) and length of ICU stay (OR: 1.052 95% CI: 1.025-1.079) were associated with a higher risk of ACR-BSI. Comparing 705 arterial catheters in femoral location with 838 in radial location, no significant differences in infection rates were found, although there was a trend toward a higher rate among femoral catheters (4.13 vs. 3.36 episodes per 1000 catheter days) (p = 0.72). Among patients with ACR-BSI, Gram-negative bacteria were isolated in 16 episodes (61.5%) in the femoral location and seven (28%) in radial location (OR: 2.586; 95% CI: 1.051-6.363).

We concluded that as has been reported for venous catheters ACR-BSI plays an important role in critically ill patients. Days of insertion and length of ICU stay increase the risk of ACR-BSI. The femoral site increases the risk for Gram-negative infection.