Upon Further Review: Femoral Venous Catheters Do Not Increase Risk of Catheter-Related Bloodstream Infection

Abstract & Commentary

By Richard R. Watkins, MD, MS, FACP, Division of Infectious Diseases, Akron General Medical Center, Akron, OH; Associate Professor of Internal Medicine, Northeast Ohio Medical University, Rootstown, OH, is Associate Editor for Infectious Disease Alert.

Dr. Watkins reports no financial relationships in this field of study.

Synopsis: In a meta-analysis, investigators found that recent studies show no difference in the risk of catheter-related bloodstream infections between internal jugular, subclavian, and femoral sites. Older studies had a lower risk for the internal jugular site compared to the femoral site.

Source: Marik PE, et al. The risk of catheter-related bloodstream infection with femoral venous catheters as compared to subclavian and internal jugular venous catheters: A systemic review of the literature and meta-analysis. Crit Care Med 2012;40(8):2479-85.

Catheter-related bloodstream infections (CRBSIs) cause significant morbidity and mortality. They are also very costly, approximately $50,000 per infection, for which hospitals are not reimbursed by Medicare and Medicaid. It is widely believed that the femoral site is less safe in terms of infection risk compared to the subclavian (SC) and internal jugular (IJ) sites. Indeed, guidelines from the CDC and IDSA on preventing CRBSIs advise against using the femoral vein for central access.1,2 In order to evaluate the evidence behind this recommendation, Marik and colleagues performed a systematic review and meta-analysis comparing the risk in adults for CRBSIs for catheters placed in the femoral vs. internal jugular and subclavian sites.

The authors identified studies published between 1966 to October 2011 that reported the rate of CRBSI at the femoral, SC and/or IJ sites. They sub-grouped according to study design and assessed heterogeneity and bias. Two randomized controlled trials and eight cohort studies were included in the meta-analysis. There was no significant difference in risk for CRBSI between the femoral and SC sites (RR 1.75, 95% CI 0.80-3.8, P = .16). Meta-regression showed a significant interaction between the risk of infection and year of study publication, where earlier studies favored the SC site (P = .05). Overall, the IJ site was associated with a significantly reduced risk for CRBSI compared to the femoral site (RR 1.90, 95% CI 1.21-2.97, P = .005). However, when two outlier studies were removed from the analysis there was no significant difference between the femoral and IJ sites (RR 1.35, 95% CI 0.84-2.10, P = .2). Meta-regression again demonstrated a significant interaction between year of publication and risk for infection, with earlier studies favoring the IJ site (P = .01). There was no significant difference in CRBSI rate between the SC and IJ sites (RR 1.09, 95% CI 0.67-1.75, P = .74). Finally, there was no difference in risk for deep vein thrombosis (DVT) between the femoral site and the IJ and SC sites combined. Significant heterogeneity was found between the studies.

Commentary

Conventional wisdom teaches that the SC vein is superior to the IJ for preventing CRBSIs, which in turn is superior to the femoral vein. The findings of the present study i.e. recent data show no difference in risk of CRBSIs between the femoral, IJ and SC sites, challenge this belief as well as current guideline recommendations about avoiding the femoral site. Moreover, a recent Cochrane review also found no difference in CRBSI rate among the three insertion sites.3 Except for certain patients for whom the femoral site should be avoided (obese, renal transplant recipients, on chronic hemodialysis), Marik and colleagues recommend that insertion sites be chosen based on the lowest likelihood of injury.

This study does have several limitations. First, one of the RCTs was conducted before the line-bundle standard was implemented and the other did not include patients with a body mass index greater than 45. It seems intuitive that changes in line insertion techniques in recent years, such as improved hand hygiene, use of chlorhexidine for skin decontamination, full-body drapes, catheter-insertion checklists, and ultrasound guidance for placement are a major cause for declines in CRBSI rates. Second, they did not distinguish between CRBSI and catheter colonization rate, as not all colonized catheters necessarily equal clinical infection. Third, the authors used data that combined outcomes for standard and antimicrobial catheters. Finally, the incidence of DVT may have declined over time due to heparin usage as part of the ventilator bundle.

Is it time to abandon the axiom about avoiding femoral central lines? Probably not yet, although the practice does seem safer now than in the past. As Marik and colleagues acknowledge, the rate of CRBSIs in the U.S. has declined from 5.32/1,000 catheter days in 1998 to 2.05/1000 catheter days in 2009. It is possible that this is due in part to clinicians not using the femoral site, but more likely it is from better catheter insertion practices. However, it may be time to re-examine current guideline recommendations and at least acknowledge that the femoral site might be an option, with the caveat that the final decision about site placement requires a careful analysis of the risks and benefits.

References

  1. O’Grady NP, et al. Guidelines for the prevention of intravascular catheter-related infections. Clin Infect Dis 2011;52:e162-93.
  2. Marschall J, et al. Strategies to prevent central-line associated bloodstream infections in acute care hospitals. Infect Control Hosp Epidemiol 2008;29(Suppl1):S22-S30.
  3. Ge X, et al. Central venous access sites for the prevention of venous thrombosis, stenosis and infection. Cochrane Database Syst Rev 2012;3:CD004084.