Prospective study of peripheral arterial catheter infection and comparison with concurrently sited central venous catheters*

OBJECTIVE: Peripheral arterial catheters are perceived as having low infective potential compared with other catheters and may be overlooked as a cause of catheter-related bloodstream infection. We aimed to measure colonization and rates of catheter-related bloodstream infection in arterial catheters, to investigate risk factors for arterial catheter colonization, and to compare arterial catheter infection rates with those in concurrently sited and managed central venous catheters. DESIGN: Prospective 24-month cohort study. SETTING: Eight-bed combined general intensive care and high-dependency unit of a 350-bed Australian teaching hospital. PATIENTS: Three hundred twenty-one arterial catheters in 252 adult and pediatric patients were observed for 1,082 catheter days, and 618 central venous catheters in 410 patients were observed for 4,040 catheter days. All catheters were inserted in, or presented to, the intensive care unit. Both arterial catheters and central venous catheters were inserted by trained personnel under aseptic conditions, and management was standardized. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The incidence per 1,000 (95% confidence interval) catheter days of colonization (> or = 15 colonies) and catheter-related bloodstream infection was 15.7 (9.5-25.9) and 0.92 (0.13-6.44) for arterial catheters and 16.8 (13.3-21.3) and 2.23 (1.12-4.44) for central venous catheters. Arterial catheter colonization was not significantly different than that in central venous catheters (hazard ratio, 1.17; 95% confidence interval, 0.41-3.36; p = .77). Arterial catheter colonization increased with dwell time and was similar to central venous catheters over time. Femoral arterial catheters were colonized more often than radial arterial catheters (hazard ratio, 5.08; 95% confidence interval, 0.85, 30.3; p = .075), and colonization was significantly higher when the catheter was inserted in the operating theater or emergency department (hazard ratio, 4.45; 95% confidence interval, 1.42-13.9; p = .01) compared with the intensive care unit. CONCLUSIONS: The incidence of catheter-related bloodstream infection from arterial catheters was low. However, both arterial catheter colonization and rates of catheter-related bloodstream infection were similar to those in concurrently sited and identically managed central venous catheters. By inference, the arterial catheter should be accorded the same degree of importance as the central venous catheter as a potential source of sepsis.