Forum topic

We consistently call the area closest to the cavoatrial junction the distal location.  

I think in this context it is the location compared to the insertion point and not the location in relation to the heart.  All of the published articles that identify the tip location describe the cavoatrial area as distal.  

Gwen Irwin

Austin, Texas

Hi, Erica!

My PICC instructor required me to take the BARD PICC insertion online course.

In the section on veins it explained the distal SVC is the lower end, and closest to the heart and the proximal SVC is the upper SVC, farthest from the heart. This is counterintuitive because we would normally think the lower SVC is closer to the heart and should therefore be called the proximal SVC.

The lesson went on to say that you need to think of the aorta being proximal to the heart, the arteries distal to aorta, the arterioles distal to their arteries, the capillaries distal to the arterioles, the venules distal to the capillaries, the veins of the arm distal to their venules, the inomminate vein as distal to the right arm veins, the SVC as distal to the inomminate vein, and the most distal point of all along this long trail that started at the other side of the heart, is the lower SVC, that is the distal SVC.

I have been following that nomenclature without any disapproval.

Art 

I would advise that you avoid using these words. The reason is that they require a reference point and that is different for many professioals. So communication with these words becomes difficult. For many, but not all, healthcare professioals the reference point is the center of the patient. This would make the SVC at the cavoatrial junction be labled as proximal or closest to the center of the patient. Others use other things as the reference point as Art described. Engineers who desgin catheters use themselves as the reference point, meaning that the shortest catheter extention leg with the lumen exit at the internal tip is labeled as the distal end, although it is closest to the center of the patient. I think use of these words only adds confusion so would recommend other anatomical descriptors such as the lower SVC near the cavoatrial junction. Or upper SVC near the junction with the innominate vein, or middle SVC. Lynn

I have had the same issue with our pediatric radiologists calling the area near the cavo-atrial junction the proximal SVC, in contrast to most of the nursing literature which refers to it as the distal SVC. It seems Lynn's suggestion is wise: use lower or near c-a junction vs upper or mid svc.

 I use the "distal SVC" because there is consistent understanding within our HCO that that means the lower third.  We actually (currently) document " ___ (#) of cms below the carina" and avoid distal SVC /lower third or cavoatrial junction altogether.  I realize that 3-5 cms below the carina is very arbitrary but the radiology department wanted to be internally consistent.  It may be easier to use "lower third", "mid-SVC" or "upper third of the SVC".  Interventional radiologists typically describe proximal the beginning portion of a vessel, and "distal" as the end portion of a vessel so that there is consistency with blood flow.  

When I teach, I use both terms:  "proximal third of the SVC or the upper 1/3 of the SVC", and "distal SVC or the lower 1/3 of the SVC" for clarity.  I'm sorry I didn't do that in my article.