Usefulness of the external jugular vein examination in detecting abnormal central venous pressure in critically ill patients

Background: Central venous pressure (CVP) provides important information for the management of critically ill patients. The external jugular vein (EJV) is easier to visualize than the internal jugular vein and may give a reliable estimate of CVP. Methods: To determine the usefulness of the EJV examination in detecting abnormal CVP values, we performed a prospective blinded evaluation comparing it with CVP measured using an indwelling catheter in critically ill patients with central venous catheters. Blinded EJV examinations were performed by clinicians with 3 experience levels (attending physicians, residents and fellows, and interns and fourth-year medical students) to estimate CVP (categorized as low [<= 5 cm of water] or high [>= 10 cm of water]). The usefulness of the EJV examination in discriminating low vs high CVP was measured using receiver operating characteristic curve analysis. Results: One hundred eighteen observations were recorded among 35 patients. The range of CVP values was 2 to 20 cm of water. The EJV was easier to visualize than the internal jugular vein (mean visual analog scale score, 8 vs 5; P <.001). The reliability for determining low and high CVP was excellent, with areas under the curve of 0.95 (95% confidence interval [CI], 0.88-1.00) and 0.97 (95% CI, 0.92-1.00), respectively, for attending physicians and 0.86 (95% CI, 0.78-0.95) and 0.90 (95% CI, 0.84-0.96), respectively, for all examiners. Conclusion: The EJV examination correlates well with catheter-measured CVP and is a reliable means of identifying low and high CVP values.