There are various protocols but our center we have used the protocol from the PD access guide 2022 from Baxter. 
Procedure to instill tPA:
1. Estimate total volume of catheter and transfer set
2. Reconstitute tPA at dilution of 1mg/mL
3. Aspirate contents of catheter
4. Connect syringe to transfer set and inject 110% of calculated volume of tPA
5. Allow tPA to remain in catheter for 1-2 hours
6. Aspirate tPA from catheter
7. With 60 mL syringe, briskly irrigate the catheter with saline to determine patency and
dislodge any fibrin clots
References:
Zorzanello M, Fleming W, Prowant B. Use of tissue plasminogen activator in peritoneal dialysis catheters: a literature review and one center’s experience. Neph Nurs J 2004;31:534-7.
Crabtree JH. Rescue and salvage procedures for mechanical and infectious complications of peritoneal dialysis. Int J Artif Organs. 2006; 29:67-84.