Central venous pressure in a femoral access: a true evaluation?

Introduction

In patients with bad vascular access, the evaluation of central venous pressure (CVP) obtained in a femoral vein could be an alternative to the evaluation in central venous catheters (CVCs) located in internal jugular or subclavian veins.

Objective

To compare CVP measurement obtained in two different locations (jugular or subclavian veins and femoral veins).

Setting

A 16-bed medical–surgical ICU.

Materials and methods

This study began about 2 years ago, and the CVP of 41 patients in our ICU were evaluated and compared. Each one of those 41 patients had a CVC in two different locations, one placed in the internal jugular or subclavian veins, and a second in a femoral vein. Simultaneous measurements of CVP were undertaken by two different operators, with a pressure transducer zero referenced at the mid-chest. Standard CVCs with similar features (20 cm length) were used. The patients with an intra-abdominal pressure (IAP) > 15 mmHg were excluded. The IAP was previously evaluated in all patients, using the method described by Sugrue and Hillman. A linear correlation analysis was performed, considering significance P < 0.05 and a correlation coefficient > 0.85.

Results

Forty-one patients were studied, and four patients were excluded due to an IAP > 15 mmHg. The mean age was 63.7 ± 16.2 years, the ICU stay was 10.4 ± 3.5 days, the APACHE II score was 27.8 ± 6.7, and SAPS II was 55.8 ± 11.2. The mean CVP measured with jugular/subclavian access was 11.3 ± 4.5 mmHg, and in the femoral access was 11.8 ± 4.4 mmHg. The linear correlation between those measurements was 0.96, and P < 0.007.

Conclusion

The CVP can be accurately measured in a femoral vein, using standard CVC, in patients with an IAP < 15 mmHg.