Non-simultaneous kidney exchange chains

Quite a few kidney exchange chains, starting with a non-directed (altruistic) donor, have been done non-simultaneously, since the first non-simultaneous extended altruistic donor (NEAD) chain went through so successfully. The idea is that the need for simultaneity is reduced when a chain starts with a non-directed donor, since no incompatible patient-donor pair is left waiting for a kidney after giving one.

Here's an article about a recent non-simultaneous chain in Maryland: the article gives a good idea of the multiple reasons why non-simultaneity might be desirable. First, it relieves logistical constraints involved with scheduling multiple operating rooms (not to mention waiting rooms and recovery rooms), and second, it allows the chain to continue in the future.

""Four people who otherwise would not have had matching donors now have lifesaving kidneys - from people they've never met. And this transplant chain was set in motion by a man who simply wanted to donate a kidney to someone in need," says Matthew Cooper, MD, director of kidney transplantation at UMMC and associate professor of surgery at the School of Medicine, who oversaw the series of surgeries.
Only a handful of hospitals in the country have performed large kidney transplant exchanges such as this one. The procedures, which took place over two days in four operating suites at the medical center, required extensive coordination and planning not only in the operating rooms, but also in the waiting rooms.
Because the right to privacy for the donors and recipients is protected throughout the process, transplant coordinator Debbie Iacovino arranged separate waiting areas in different parts of the hospital for their families to ensure anonymity.
The kidney exchange started with a 59-year-old man from a suburb of Boston, Mass., who offered to donate a kidney to someone in need. His kidney was given to a Maryland man who was not a match with his intended donor, a woman who is also from Maryland. The woman was matched with a 10-year-boy from Catonsville whose kidneys were failing because of a congenital abnormality.
A friend of the boy's family, a 50-year-old lawyer from Catonsville, gave his kidney to a 64-year-old Florida man, whose wife was a donor for 74-year-old man from Virginia Beach, Va. The Virginia man's son-in-law will be a "bridge" donor, who will give his kidney to a yet-undetermined recipient at a later date, which will allow the chain of transplants to continue."

Here's a video interview:
Video FourWay Kidney Exchange An Interview with Dr Matthew Cooper
http://www.spokenword.org/program/865751 21 minutes

"UMMC's director of kidney transplantation Dr. Matthew Cooper provides an overview of the four-way kidney exchange that involved eight patients from four states on November 2 and 3. Dr. Cooper talks about paired kidney exchanges, how this four-way exchange came about, what happened during the two days of surgery, the significance of this procedure for the people involved and much more."