Types of Living Exchanges
• Simple gift – as it sounds
• Paired exchange – also as it sounds.
Motivated by ABO incompatibility, positive
crossmatch
• Cascade exchange – see board diagram.
Motivated by ABO incompatibility, positive
crossmatch, and often desire to increase
transplants
• Continued next slide
Types of Living Exchanges
(cont)
• List paired exchange – (Living) donor 1
donates an organ to UNOS wait list
(recipient 2). Afterward, recipient 1 is
given highest priority for the next available
ABO compatible organ from the list. Why
would anyone do this? Hint: has to do
with ABO incompatibility…
• List cascade exchange – as above, only to
start a cascade exchange (see previous
slide)
A worry about list paired and
cascade exchanges
• “The potential harm to wait-list candidates
of blood type O was raised by Ross and
Woodle in 2000…and the data from
Region 1 has confirmed those fears. In
the first 17 list-paired exchange
transplants performed, only 1 donor was of
blood type O...and only one recipient of
the next appropriate deceased donor
organ was not of blood type O (Delmonico,
et al. 2004)” (Ross, 2006)
Worry (cont)
• “Thus, even though the number of organs
is increased by the list-paired exchange
program, it is increased at the expense of
those who are already worse off. Since
candidates of blood type O already have a
longer than average wait time, these
exchanges further disadvantage those
who are already worst off…” (Ross, 2006)