Fibrin sheath and port occlusion

[StephN]

Since a few of us here have had port problems, thought I would add a little more information on the causes of clogging.

I posted and then the server problems here "ate" a few threads including mine on the port problem, which had some good replies and perhaps some I did not see.

My catheter line had a small loop in it a little ways past my port and this must have happened at the initial placement according to my experts at the cancer center. This was discovered during a DYE STUDY done under a Flouroscope, which is also what they use to follow the insertion of the catheter in a new placement. The loop was not obstructing. The problem was a fibrin sheath that had thickened where the catheter enters the vein.

Here is some info on how this happens. Another site I read said that fibrin buildup starts only a few minutes after the catheter is placed in the vein. This is from the platelets and clotting factors that come rushing to the incision site.

Central Line Complications

Partial Catheter Occlusion

Causes:

* Common occurrence in long-term catheters secondary to long dwell-time of these catheters.

* Encasement of the catheter by a fibrin sheath. The fibrin sheath may also become seeded with microorganisms which may disseminate into the bloodstream.

*Residue of blood products deposited within some central venous access devices each time blood is aspirated or infused.

*Small clots adhering to the catheter tip.

*Drug precipitation adhering to the wall of the catheter.

Signs and Symptoms:
* Withdrawl occlusion - the inability to withdraw blood from the catheter but are able to infuse fluid. The fibrin sheath or blood/drug precipitates acts as a flap over the tip of the catheter when blood is withdrawn but opens when fluid is injected.

Interventions:

* Do not infuse any product through a central line that does not have a blood return.

*Notify the physician.
* May need chest x-ray for verification of tip placement.

Prevention:
* Strict adherence to the flushing protocol before and after drug infused and after blood drawn.

*With persistent withdrawl occlusion, may need to follow the fibrinolytic agent protocol to lyse the fibrin sheath or cleanse the catheter of residual blood products.


http://www.rncentral.com

Steph - thanks for this info. Have been unable to draw from port last two infusions and nurses did not seem concerned - I will point this info out to my onc this week. Again thanks!

[mamacze]

Dear Steph,
Thank you once again for providing helpful info, this time for your sisters with ports. I am grateful to catalogue this in the dusty annals of my mind for future reference should I need it.
Love Kim from CT

[Lolly]

Steph, I can completely symphathize with your ordeal as I am on my third port since 2001. My problems were caused by "pinch-off" syndrome, and I've copied a PubMed article and included the link so others can be aware of this rare complication. The symptoms are very similar to those caused by a fibrin sheath, but my ports would also be difficult to infuse, a give-away for this complication. My surgeon finally got around this problem by by-passing the clavicular junction and accessing the vein in my shoulder.
Even though I've had a few problems with my port(s), I would not consider doing without it as I only have one good vein in my one good arm (lymphedema in the other).

Pinch-Off Syndrome/PubMed
http://www.ncbi.nlm.nih.gov/entrez/q...&dopt=Abstract

Pinch-off syndrome: a rare etiology for central venous catheter occlusion.

Andris DA, Krzywda EA, Schulte W, Ausman R, Quebbeman EJ.

MedicalCollege of Wisconsin, Department of Surgery, Milwaukee53226, USA.

BACKGROUND: Catheter pinch-off syndrome is a rare and often misdiagnosed complication of tunneled Silastic central venous catheters. Pinch-off syndrome occurs when the catheter is compressed between the first rib and the clavicle, causing an intermittent mechanical occlusion for both infusion and withdrawal. We report its incidence in a large series of catheter insertions and describe the clinical presentation, radiographic findings, and recommended treatment. METHODS: A total of 1457 tunneled Silastic central venous catheters that were inserted using the percutaneous subclavian approach were prospectively studied. Indications for catheter placement included bone marrow transplant, continuous or intermittent chemotherapy, long-term antibiotics, and parenteral nutrition. Catheters were evaluated for clinical presentation of an occlusion relieved by postural changes and radiographic findings of luminal narrowing. RESULTS: Pinch-off syndrome was identified in 16 (1.1%) catheters. Radiographic findings were present in all catheters; clinical findings were present in 15 catheters. Clinical symptoms presented within a median of 2 days after placement (range, 0 to 167 days). Partial or complete catheter transection, a serious sequela of catheter pinch-off syndrome, occurred in 19% of the identified catheters. CONCLUSIONS: (1) Catheter pinch-off syndrome presents clinically as a catheter occlusion related to postural changes; (2) clinical symptomatology should be confirmed radiographically; and (3) catheter removal with a more lateral replacement in the subclavian vein or in the internal jugular vein will avoid a recurrent complication.

[sarah]

Sorry to hear so many of you have had port problems.

Steph,
the article stated:
Interventions:

* Do not infuse any product through a central line that does not have a blood return.

does that mean they should do a blood withdrawal before infusion or is it just a check afterwards? I think they just flush fluid through it first before infusion and only after the infusion at the end do they withdraw blood which they throw away.
thanks
sarah

[StephN]

Hi Sarah -
I know when my port is accessed the nurse will get ready to flush, but also checks for blood return. They sort of tease the syringe back and forth till they see a little blood entering the short line. You may not be aware of this as you would have to be looking down and watching.

The first time there was no blood return, the nurse was not worried as it flushed so normally/easily. The fear is that if there is no blood return there could be some leakage of the drug outside the catheter where it enters the vein. Some drugs should not reach tissue in this way. Since I was only getting Herceptin and not the harsh, really toxic stuff, the concern was minimal until it became the norm to where was NEVER a blood return any more.