Hello to the panelist wonderful roundtable. My name is Cutberto Cortés from Mexico city. I have a question. Do you know if there is a formula o something like that to get the right size to chosse the right catheter to the right patient.

In general, for the RIJ I use a 23cm Tip to Cuff, for the LIJ 27cm Tip to Cuff and for femoral catheters 50cm Tip to Cuff.
However, as discussed in the webinar – this is highly variable based on tunnel length and patient size. We generally see the best flows when the tip is in the deep right atrium – regardless of the catheter length, it usually the tip position that makes the biggest difference in the blood flows.
For catheter exchanges, its generally easy to use fluoroscopy to visually estimate how much longer or shorter you would like to place the new catheter.
One technique that can be helpful to try to estimate catheter length for a new insertion is to lay a wire on the patient and, under fluoroscopy, try to estimate the path of the wire from your exit site to the right atrium. You can then bend the wire at estimated lengths and use a ruler to measure an ideal catheter length.
There are also guidewires available with measurement markers directly on the wire (I believe BD had some of these wires available as part of their kits.)
However, this is a bit cumbersome, and admittedly I tend to estimate the lengths after looking at the fluoroscopy images – usually relying on my usual lengths for RIJ, LIJ, and femoral catheters. But you need to take your expected tunnel length into consideration as well.

Daniel, I enjoyed your presentation very much - always love hearing someone agree w/ me re jug TDC length. . HOWEVER - from a transplant surgeon's perspective, iliac vein and IVC thrombosis preventing subsequent transplantation is the direst complication of long-term dialysis catheter use. And for that reason, we've avoided use of very long femoral TDCs, preferring to use the left iliac vein whenever possible and placing the tip either right at or just above the caval bifurcation. In general, we've not have a flow rate problem with this approach (no data, just my impression). Do you have data showing better flows with 50cm catheters placed in the RA?

This is reasonable - in my experience I seem to get much better flows when parking the catheter tip as close to the right atrium as possible. I seem to have a harder time keeping reliable flows at the caval bifurcation.

That being said, we have a few patients where we keep the tips at the bifurcation in consideration of transplant – but I seem to be exchanging these catheters far more frequently.

I’ve always considered the flow dynamics here analogous to tip placement at the SVC versus the right atrium for chest catheters. But I am unaware of any good data here.

Again, individualizing care to the patient is important. If the patient is a reasonable transplant candidate, then attempting a more distal tip location is reasonable.

In my area, by the time patients reach the stage of femoral catheters we’ve exhausted multiple access options and are usually not ideal transplant candidates. These patients seem to have a multitude of cardiac and vascular issues that usually preclude them from transplantation. At that point, we just tend to try to do the best we can with the femoral catheters, and I seem to do better with the longer lengths.

However, I may try a Centros at the caval bifurcation next time I see one of these patients, just to see how they do.

Good morning. Since I always cannulate the vein with a micropuncture sheath for TDC placements, I have found an easy technique that is pretty "idiot proof" when coming from the neck. Once you have cannulated your vein, advance your micropuncture wire until the tip is deep in the right atrium. Put your micropuncture sheath in and bury it to the skin surface. Before you pull your microwire, mark it with a hemostat then have your scrub tech measure from the tip of the wire to the hemostat. Subtract 5 cm (which is the usual distance from the skin to tip created by the external portion of the micropuncture sheath with the internal style in place). That is your distance from the venotomy site to your targeted catheter tip location within the right atrium. From there either measure or estimate the distance from the venotomy to the subclavicular area for your exit site and create it based upon the lengths of the catheters you have available. I have been using this technique for almost 20 years and it is pretty spot on. Takes only a couple extra seconds while your tech measures the distance on the micropuncture needle.

I agree with Dr. Patel... target deep in the right atrium if possible as it was allow for a little adjustment of the catheter tip when the patient is upright. Also try to keep the exit site close to the subclavicular area rather lower on the chest to decrease the amount of movement related to body habitus.

Randy, excellent comments...marking your access wire works from any access site and one can consider doing this routinely.....

On tip position... when the patient is supine vs. upright.

"Catheter migration after chest wall CVAC placement is a common event. The catheter tip should be initially positioned approximately 3-4 cm more centrally than the desired final position...."

J Vasc Interv Radiol May-Jun 1997;8(3):443-7. doi: 10.1016/s1051-0443(97)70586-4.
Migration of central venous catheters: implications for initial catheter tip positioning
C M Kowalski 1, J A Kaufman, S M Rivitz, S C Geller, A C Waltman

Great discussion. Sometimes the routine isn’t always so routine. I try to avoid placing the catheter tip deep in the RA, only just beyond the Cava-atrial junction to account for some migration in the upright position. I also use Dr. Cooper’s method of measuring with the micropuncture wire and adjust the tunnel accordingly.
I have always wondered what the significance is of ectopy while flushing the catheter after placement. When seen I try to pull the catheter back a cm or two or use a shorter catheter. If I am noticing ectopy while flushing, is the patient having it during dialysis and is it insignificant?
Ajay

The Cannon Arrow II catheter allows you to place the tip first then create the tunnel in a retrograde fashion so the only estimate is where the exit site will be, not the tip.

After accessing the IJV/EJV with a micro access kit an passing the guidewire to the IVC (regular wire from the right and firm from the left/for better tracking), and similar to what Randy has highlighted, for the past 20 years, we have used a Coons dilator (20cm long with 7cm long tapered 7 to 14 french segment, semi-stiff tip) to position deep in the RA and measure what is left sticking out from the venotomy. Since it is a known length, if for example, 5cm is sticking out (that u can measure with the back end of ur scalpel that is usually graded), then we choose 19cm tip to cuff and make a 5cm tunnel. This method will allow u to use single catheter kits (without having to open a whole tray) that we introduce sheathless as we do with all our catheters….
Few pointers along the lines of prior comments:
-it is more accurate to gage the length from the inside than the outside especially in barrel chested patients
-it is better to make the tunnel laterally to subclavicular area (candy cane rather than a V-shaped course) than bringing it medially to minimize movement with upright position especially in women with large breast
- keeping the tunnel at 5-8cm length (not too short and not too long) is appropriate as opposed to bringing the TDC out from the breast! ( I am sure some of u have seen that)
-agree that triggering ectopies with the flush an pull should prompt us to reposition (slit and oblique oriented RA are prone to that), this requires a long discussion by itself for tip position that vary from one individual to another
- for femoral TDC, we gage the length to the RA with a straight catheter
- we have 4 catheter designs for different reasons including Cannon (another long discussion on the design topic)
- no suture at exit site, only 1 at the wings, no peel away (only exception is Cannon), all sheathless insertions
- etc
Best regards,
Tony Samaha

Great discussions, Thank you all, I have a few questions if some could help answer
1. supine vs upright position - Does TDC catheter migrate centrally or peripherally by 2-3 cm ? Drs. Falk and Kumar discussions seem to be contrasting.
2. Tip of micropuncture wire is floppy- When using micropuncture wire to guage length of tunneled catheter, are we measuring length from crimple to the tip of floppy end of wire or crimple to the tip of rigid end right before origination of floppy portion of guidewire?

The TDC tip will migrate more peripherally. when upright.. and it will be more pronounced from the LIJ (vs RIJ), in more obese (vs. less obese) patients, as well as in patients where the catheter is sutured to the skin lower over the chest... especially if over the breast.

The measurement is from the tip of the floppy end of the micropuncture wire to the point it exits the micropuncture sheath (with internal stylet)

Sorry, after rereading my 11pm comment it may not have been clear. The catheter does get pulled up when sitting upright. Many times I ask the patient to take a deep breath which can demonstrate this. I aim for the tip to be just beyond the Cavo-atrial junction and not deep into the RA. I crimp the micropuncture wire with the sheath pushed in then measure the crimp to floppy tip and +5, pick the closest size catheter and modify tunnel as necessary. That being said this is an art that has to be modified based on body habitus, resp movements, etc. I try to avoid the IVC placements due to the concern for ectopy and movement of the tip out of the IVC.

Thank you for the clarification Drs. Cooper and Kumar.

Thank you all for great presentation and subsequent discussions.
In women with large breasts / whenever I feel that significant soft tissue drag would be a problem, marking the site of intended catheter exit site while the patient sitting up helps - as the surface anatomy changes quite a bit upon lying down.
A short tunnel and a more lateral exit site in these patients minimizes drag as mentioned previously.
Really looking forward to discussion on fibrin sheath and catheter associated thrombus management -a vexing problem.
Thank you.
Suresh - UC Davis, Sacramento CA