Can Central Venous Pressure Be Measured with a Femoral Line?

There is controversy about whether venous pressure measured below the diaphragm accurately reflects central venous pressure (CVP). These Saudi authors placed 18 cm venous catheters in the right atrium (confirmed by radiograph) and the common iliac vein via the femoral vein. They then measured pressures simultaneously in 12 men and 14 women. All patients were on ventilators.

Correlation between iliac and atrial CVP was 0.987 (p<0.0001) and the mean difference between the pressures was 0.93 mm Hg. In only one case did the atrial CVP differ from the iliac CVP by more than 2 mm Hg.