I reviewed ultrasonography to confirm central line position in 2015 here, reaching these conclusions:
- It's OK if the line tip is in the right atrium, superior vena cava, bracheocephalic vein, or subclavian vein.
- The rapid flush test is adequate to confirm placement within a vein.
- Line position can be confirmed ultrasonographically as shown here:
My experience since then
Since 2015 this has worked fine, with one exception. A severely obese woman underwent ultrasound-guided right subclavian central line placement. Although the target was deep, line placement was not difficult. The line was sutured at 15cm and a flush test demonstrated intravascular placement. Unfortunately, later on the patient moved around and the catheter tip was pulled out of the vessel. In retrospect, given how deep the target vessel was, the line should have been advanced further to prevent dislodgment.
Hourmozdi et al. Routine chest radiography is not necessary after ultrasound-guided right internal jugular vein catheterization. Critical Care Medicine 2016; 44:e840.
This is a retrospective study of 1,322 ultrasound-guided right internal jugular vein catheters. Procedures were performed at various locations within multiple centers in the Henry Ford system, mostly by trainees.
Post-procedure chest X-rays detected one pneumothorax and seventeen line “misplacements.” Four chest X-rays were interpreted as showing a pneumothorax, but ultimately three were determined to be a false-positive (25% specificity).
Its debatable whether these “misplacements” were clinically significant. Fifteen of the “misplaced” catheters were located in the brachiocephalic vein or subclavian vein, which is probably OK (four were used without adjustment). One catheter was in the inferior vena cava and another was in the right ventricle – so some catheters were indeed too deep.
The authors concluded that post-procedure CXR isn't necessary. I disagree. My conclusion from this data is that you don't need a post-procedure CXR following right internal jugular vein central line placement, as long as:
- Post-procedure ultrasonography excludes pneumothorax
- The line isn't inserted too far (avoiding placement in the right ventricle).
Overall, this study supports the concept of ultrasonographic line confirmation in the right internal jugular vein (figure below). Hopefully, future studies will provide evidence regarding other sites (e.g. left internal jugular, subclavian).
Related
- Can we use ultrasonography to confirm line position? (PulmCrit)
- How to place a central line, also CVC show part I, part II (EMCrit)
Hi Josh
Great review
I have been using US as described for a while now
I use the subcostal window to:
1- look for the flush
2- check if I can see the actual catheter in the RA or RV ( ie too far)
I’ve had a few which have made their way into the contralateral subclavian etc and noticed te flush test to show a ” delayed bubbling” – the bubbles arrive 5-10 seconds later than you’d expect
Can we use it this way to help guard against these pitfalls?
Casey Parker
Hi Casey,
Thanks, I agree. My feeling is that placement in the subclavian can almost always be suspected on the basis of one or more of the following:
(1) wire hangs up after passing it about 1/2 way into the patient
(2) one of the ports doesn’t flush well (eg distal port)
(3) delayed visualization of bubbles as you describe
(4) catheter itself can be visualized in the subclavian vein
My question is whether it matters if a line is in the subclavian. I don’t like repositioning lines as unnecessary manipulation may increase the risk of infection. Placing a new line exposes the patient to all of the risks of line placement. So my usual practice is to just use a line in the subclavian position (while avoiding infusion of pressor or caustic solutions into the distal port). It’s not 100% clear what the best thing to do here is. Would be nice to gain more clarity on this, it tends to be more relevant with subclavian lines than IJs.
Josh
Have you got updates on this topic (subclavian misplacement via IJV approach) since 2016? Do you still discourage vasopressors by distal port in this case?
I got a misplaced line recently and I can confirm that wire hanged up after passing about 1/2 way into the patient but after confirmed venous placement by intraprocedural ultrasound I tried to put the catheter in without any resistance. Each port flushed properly. X ray confirmed misplacement in omolateral subclavian
Thank you very much and greetings from Italy
Giacomo