Forum topic

I have seen policies like that before, and they are based on things that we assumed before there was so much good research on the topic.

The reason for checking a blood return is to determine patenvy. There are several things that could go wrong if there isn't a blood return, the least problematic is a fibrin sheath. I have found that if there are problems with a new port, it can be from a misplaced tip, a kink, pinch off syndrome, or something along those lines.

Also, how can you be sure that you would detect an infiltratoin. A breach in the line could be anywhere along the line, and most of a port line is under bones and near important organs.

There is good info in the INS Standards, and I believe this subject has been discussed in this forum previously (use the search).

Basically if there is no blood return the only good options you have are to attempt to declot with Cathflo or do a chest x-ray. Which to do first is still open to discussion if I am up to date on that. For me it often depends on the history of the line. I often look at the post insertion x-ray if it is a new line. Not all surgeons are current on correct tip placement.

Hope this helps

Gail

 "Fibrin clot" is not quite an accurate term. Fibrin sheath may be present but this contains platelets, serum proteins, and WBCs, but is not a typical thrombosis with RBCs. A fibrin sheath can have a full thrombosis on top of the fibrin. Also, a thrombosis older than about 2 weeks is very stable because smooth muscle cells have also moved into the thrombus, meaning that a thrombolytic agent will not be sufficient to remove the problem. So catching fibrin and/or thrombus early is the key to successfull removal. But the procedure for instillation is only reaching what is inside the lumen and directly at the catheter tip. 

I agree that your procedure seems to be based on "conventional wisdom" before there was research to give us a better understanding of catheter associated thrombosis. Fibrin sheaths are going to be present in virtually all catheters as they can develop within 24 hours of insertion. Upon removal, the fibrin is known to strip off the catheter and float into the bloodstream but is not thought to cause a problem. A complete thrombosis is a very different thing though, as this can produce pulmonary emboli of varying sizes. The rate of PE associated with catheter associated thrombosis is increasing. A fibrin sheath can form in several ways. A fibrin tail or flap is just over the catheter tip. A partial sheath would be like a sock extending partway up the catheter length and a complete fibrin sheath would cover the entire catheter length from tip to insertion site. The complete fibrin sheath is the primary concern for infiltration/extravasation as this will allow for retrograde flow between the fibrin and catheter wall and exit at the venotomy site. This will allow fluid into the SC tissue. As has already been mentioned, there are many other significant causes of lack of blood return on an implanted port and these have been documented to produce severe extravasation into the mediastinum or other thoracic areas. 

The bottom line is flushing to detect resistance, and aspiration for a blood return that is the same appearance as whole blood. Anything less than that requires some other intervention before the port is used. The steps depends upon your policy - either immediate contrast injection under fluoroscopy to determine the fluid flow pathway and rule out all factors that could produce infiltration/extravasation OR use of a thrombolytic agent first to assess the outcome for blood return. Lynn