Central venous catheter placement: where is the end of the line?

Introduction

There is still controversy regarding safe placement of central venous catheters (CVCs) as to where the tip should lie to avoid mechanical complications whilst maintaining effective use [1, 2]. The carina has previously been suggested as a useful landmark to avoid intracardiac placement and its associated risks, and also that the catheter tip should lie within the superior vena cava parallel to its walls [1, 2]. However, this has been disputed and there remains no consensus as to optimal tip placement. To gauge our current practice we performed a retrospective review of CVCs placed via the internal jugular or subclavian route in intensive care patients to assess where CVC tips were placed.

Methods

We retrospectively reviewed the chest radiographs of 197 consecutive intensive care patients admitted on and before 30 June 2011. A total of 101 patients had evidence of 137 new CVCs. For each new catheter the Picture Archiving & Communication System was used to record the tip position (after any repositioning) in relation to the carina and the degree of angulation from the vertical.

Results

Twenty-five per cent (34/137) of all catheter tips lay >10 mm below the carina, therefore potentially increasing the likelihood of intracardiac placement. This was reduced for left-sided catheters (6/37; 16%). All right-sided catheters lay at an angle <30°. However, 38% (14/37) of left-sided catheters had not crossed the midline, and 59% (22/37) lay at an angle >30° to the vertical. Only 11% (4/37) of left-sided catheters had crossed the midline and lay at an angle of <30°, and all of these lay below the level of the carina. No immediate complications of insertion were identified. See Table 1.

Table 1 Site of CVC insertion (n= 137)

Conclusion

There was a wide variation of catheter tip placements accepted without re-positioning. Left-sided catheter tips are more at risk of less precise (and thus potentially nonoptimal) placement. Our results indicate that a clearer placement strategy is required.