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Optimized method for correct left-sided central venous catheter placement under electrocardiographic guidance.

BACKGROUND
Central venous catheter (CVC) placement under ECG guidance in the left thoracocervical area can lead to catheter misplacement. The aim of this study was to identify the cause and quantify the magnitude of this error.


METHODS
CVCs were sited in either the left or right internal jugular (IJ), subclavian (SC), or innominate (brachiocephalic) vein using the Seldinger technique and a total of 227 insertions were studied. The position of the catheter tip was confirmed with two different intra-atrial ECG monitoring methods (Seldinger's wire vs 10% saline solution). Measurements were compared between the two methods and correlated to the different access sites.


RESULTS
All right-sided CVC had the line tip in the optimal position and both intra-atrial ECG recording by Seldinger's wire or 10% saline delivered correct results. For left-sided lines, however, the two methods gave significantly different results regarding the position of the line tip for each insertion site. When using the Seldinger wire as intravascular ECG lead, the results differed from the saline method by a mean of 21 mm for the IJ and 10 mm for the SC.


CONCLUSIONS
CVC placement under ECG guidance is a reliable method to site the line tip at the optimal position. However, when using a left-sided thoracocervical access point, the Seldinger wire-conducted ECG delivered a constant error. This could be adjusted for by advancing the CVC 20 mm in addition to the wire-based measurement of the insertion depth at the left IJ vein and 10 mm at the left SC vein.