Overall Topic:

Risk of catheter-related bloodstream infection in patients with femoral central venous catheters

Clinical Question:

What is the evidence regarding catheter-related bloodstream infections (CRBI) associated with central access using the femoral vein compared to other sites?

The Quick Answer:

There is no RCT evidence that femoral access has a higher rate of CRBI compared to other sites, although there is some evidence that catheter colonization occurs at a higher rate in femoral lines.

The Longer Answer

Why are we interested in this question/brief introduction?

CDC guidelines recommend avoiding the femoral vein for central lines due to increased infection rates.1 This is referred to as level 1a evidence, but a 2012 systematic review disputed the recommendation, concluding that there is no level 1a evidence and that recent studies show no significant difference in CRBI based on site.2

What is the evidence on this topic?

Only 2 RCTs have addressed this topic. One compared femoral and subclavian lines in 270 patients.3 There was a trend towards higher rates of ‘catheter-related clinical sepsis’ in the femoral group, but the difference did not reach statistical significance. CRBI occurred in 6 of 134 (4.4%) patients with femoral lines versus 2 of 136 (1.5%) patients with subclavian access. However, femoral catheters were significantly more likely to be colonized than subclavian lines.

Another trial randomized 750 patients who required short term dialysis access to femoral versus internal jugular access.4 They found no significant differences in CRBI nor in catheter colonization. Subgroup analysis showed significantly increased colonization rates for patients in the femoral group who were within the highest tercile for BMI (> 28.4 kg/m2), which seems intuitive. Surprisingly though, the femoral site had a significantly lower rate of catheter colonization among patients in the lowest tercile for BMI (< 24.2 kg/m2).4 Although colonization by itself has no obvious clinical impact, it would be interesting to see if data from larger trials reflect these findings for CRBI rates.

In a 2012 systematic review and meta-analysis, Marik and colleagues2 included the two RCTs described above as well as 8 cohort studies.3-13 Overall, no significant difference in CRBI was identified comparing femoral to subclavian sites. However, the femoral site was significantly more likely to be associated with CRBI compared to internal jugular lines (risk ratio 1.90; p=0.005). Meta-regression showed a significant difference in femoral infection rate based on the year of publication, and the authors found 2 of the cohort studies to be outliers.10,11 When they excluded the data from the outliers, they found no difference between femoral and internal jugular CRBI.

A 2012 Cochrane Review had a similar conclusion,14 finding no significant differences between femoral and IJ lines regarding colonization nor CRBI – this is based on the study of hemodialysis patients mentioned above.4 They did recommend subclavian over femoral access based on increased rates of colonization, but they found no significant difference in CRBI between these two sites.14

What is the quality of evidence on this topic? Are there any limitations?

The evidence is limited, especially if using it to practice emergency medicine. The populations and comorbidities are quite different from the average ED patient requiring central access. The purpose for CVC placement and the setting in which it is inserted do not reflect our practice. Since the earliest of these studies was published, a shift towards “care bundles” has resulted in drastic decreases in infection rates,15 potentially affecting the relevance of earlier trials.

My Main Conclusions From the Literature Reviewed:

There is no strong evidence that femoral lines are associated with higher rates of CRBI. However, absence of evidence is not evidence of absence, and I am still skeptical that these lines carry no more risk than other sites. There are situations when femoral access is clearly preferable, for example when procedures are occurring near the neck, with ongoing CPR, or if a patient has a difficult time cooperating with a drape over their face; it seems perfectly reasonable to utilize the groin when IJ and subclavian access is limited. That being said, until there are better studies that assess a more representative patient population, I will avoid femoral access when possible.

If you read one paper on this topic, read this:

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

Stay tuned:

Watch out for the Venous Site for Central Catheterization trial, an RCT currently enrolling patients to compare CRBI for subclavian, internal jugular, and femoral access. This French study intends to enroll over 3,000 ICU patients at multiple sites. Completion date is set for January 2015.

For more FOAMed resources on this topic, visit our friends at:

EMCrit- Podcast 80 Uhmmm, Maybe Groin Lines Are Not So Bad with Paul Marik

PulmCCM- Femoral lines might not be so bad after all for infection risk

the NNT- Subclavian vs Femoral Central Line Placement

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