Tissue plasminogen activator (abbreviated tPA or PLAT) is a protein involved in the breakdown of blood clots. It is a serine protease (EC 3.4.21.68) found on endothelial cells, the cells that line the blood vessels. As an enzyme, it catalyzes the conversion of plasminogen to plasmin, the major enzyme responsible for clot breakdown. Thrombolysis, also called fibrinolytic therapy, is the breakdown (lysis) of blood clots formed in blood vessels, using medication. It is used in ST elevation myocardial infarction, stroke, and in cases of severe venous thromboembolism (massive pulmonary embolism or extensive deep vein thrombosis).

It can be very frustrating when you go to draw blood from a PICC line and it is clotted off. One common way to declot a PICC line is by using Alteplase (rTPA) to break up the clot. Make sure to perform this using whatever policy is in place at your hospital. I needed to use TPA on a PICC line recently and this is not only our hospital policy, but it seems to be the common way to instill TPA into a PICC line.

1. Start by grabbing your supplies: a three-way stopcock valve, an empty 10 mL syringe, and your TPA syringe.

2. Connect these to the PICC line as shown in the picture on the right.

3. Position the stopcock so it is open to the empty syringe and closed to the rTPA. Pull back the empty syringe to create a vacuum within the PICC line tubing.

4. With the syringe still pulled back (and the vacuum still in place), switch the stopcock valve so it is open from the rTPA syringe into the PICC line and closed off to the empty syringe. The rTPA will be sucked into the PICC line due to the vacuum that was created.

5. Label the PICC line tubing as having rTPA instilled.

6. Let rTPA sit for 30 minutes to 2 hours to break up the clot. Aspirate 4-5 mLs blood after dwell time is completed.

Tpa Clot Busting

5. Always make sure to follow your hospital's policy on instilling rTPA into a PICC line. This seems to be the common way to declot a PICC line using rTPA.