1. Paired (2 Way) Exchange Canadian Transplant Registry & Programs: KPD
Donor A wishes to donate a kidney to Recipient A, but they are not a match.
Registered Pair A
Registered Pair B
Recip.
Donor
Recip.
Donor
Donor B would like to donate a kidney to Recipient B, but they are not a match.
Compatible
Incompatible
Incompatible
However, Donor A is a match with Recipient B and Donor B is a match with Recipient A.
Compatible
A paired exchange can then be completed.

2. Closed Chain Canadian Transplant Registry & Programs: KPD
Registered Pair A
Registered Pair B
Recip.
Donor
Recip.
Donor
A closed chain (also called an n-way exchange) is similar to a paired exchange, except there are more pairs included and the donor of the last pair donates to the recipient of the first pair.
Compatible
Donor
Recip.
Compatible
Compatible
Registered Pair C

3. Domino Chain Canadian Transplant Registry & Programs: KPD
Donor
Recip.
Donor
Recip.
Donor
Recip.
Compatible
Compatible
Compatible
Non-Directed Anonymous Donor
Registered Pair A
Registered Pair B
Patient from Provincial Waitlist
Domino exchanges begin with a non-directed donor who donates to the recipient of an incompatible pair. There can be multiple incompatible pairs in a domino exchange. The exchange is complete when the donor of the last incompatible registered pair donates to a recipient on the transplant waitlist.