Example image from the UW Medicine kidney transplant. Image from UW Medicine on Twitter

by George Taniwaki

On January 14, UW Medicine performed its first live-tweet of a kidney transplant surgery. The surgeon was Stephen Rayhill (who incidentally was the transplant surgeon for the anonymous patient who received my kidney) and the recipient was Dave Skelton, a patient at Northwest Kidney Centers.

A live-tweet is a technique where a participant in an event provides pictures and commentary in real-time to an audience using Twitter. If you are not a Twitter user, it’s a bit hard to explain.

Dave’s kidney came from South Carolina.

Dave’s wife, Brittany, was willing to donate a kidney to him, but was not a biological match. The two asked UWMC to enter them into a kidney exchange to find a match. (UWMC is a member of the National Kidney Registry.) The NKC was able to find a match and Dave became the second patient in a chain. Two days later, Brittany underwent her donor surgery and her kidney was sent to a recipient in Missouri.

This is a long chain involving twelve donor-patient pairs (24 surgeries total). "Being part of the 12-way swap is very exciting and humbling. It is amazing the selfless commitment the donors are displaying. People are amazing and have rekindled my faith in humanity," says Dave. For more about kidney exchanges see this Mar 2010 blog post.

To see the original tweets, search Twitter for @UWMedicine #UWMedicineKidney. Note that some of the images show surgery in progress.

[Update: Removed the links to Storify, the site no longer exists.]

by George Taniwaki

I recently came across a series of articles about one very generous man. A man who decided to help a distant relative he barely knew. A man who donated his kidney to a stranger he didn’t know at all. And a man who despite being only a mediocre swimmer is now in training to swim across Lake Ontario to raise money and awareness for a camp for dialysis patients and their families.

Mike Zavitz of Pickering, Ontario was 43 years old when he offered to donate his kidney to a distant relative in 2010. They were not a match, but Canada had just introduced a new Living Donor Paired Exchange (LDPE) program that year (see Dec 2010 blog post).

The program is small resulting in a perhaps a dozen kidney swaps (see Kidney swaps explained below) per year, meaning the chances of finding a match are slim. But Mr. Zavitz and his relative were lucky enough to find a match and became one of the first participants in the Canadian LDPE program and the first one at St. Joseph’s Hospital in Hamilton, Ontario.

The story of Mr. Zavitz’s donation appeared in The Hamilton Spectator Dec 2011. Mr. Zavitz’s kidney ended up saving a young man he never met and whose name he didn’t know. In exchange, that man’s  father donated a kidney to Mr. Zavitz’s relative. The surgeries occurred on Feb 2, 2011.

Mr. Zavitz met his recipient, Jesse Hunt, for the first time a year-and-a-half later (The Hamilton Spectator May 2012).

When explaining why he did it, Mr. Zavitz said it was in response to a lifetime of second chances he has received since he was abandoned as a baby and later adopted. “They don’t make Hallmark cards saying, ‘Thank you for rescuing me from a lifetime of foster care and possibly death.’”


Figure 1. Mike Zavitz interviewed. Video still from Hamilton Spectator


Mike Zavitz keeps on giving

The story of Mr. Zavitz’s generosity doesn’t end with his donor surgery. In an Aug 2013 story, The Hamilton Spectator reports that Mr. Zavitz plans to swim 22 kilometers (14 miles) across Lake of Bays near Algonquin Park.

His swim has two purposes. The first is to raise money for the Lions Camp Dorset, a camp designed for dialysis patients and their families. It is a place where they can get away for a week, while still receiving treatment. His goal was to raise CAN$10,000 for the camp.

In a quote in the Hamilton Spectator article, Helen Walker, administrative coordinator of the camp said, “To have somebody who has been involved in a transplant want to give back is amazing. Without Camp Dorset, it would be next to impossible to have a getaway at an affordable price.”

The recipient of Mr. Zavitz’s kidney, Jesse Hunt, had this to say, “I think it’s awesome. When you are not on dialysis, you realize the freedom you have. You can’t travel [on dialysis] or go to a cottage or get on a plane. If you can get away, it’s very important.”

Mr. Zavitz’s second goal is to raise awareness for organ donation, and especially living donation. His long distance swim shows people that organ donors can still live incredibly active lifestyles. In fact, becoming a donor may be a life changing event that actually makes you more mindful and more active.

A follow-up report on CKLP FM radio Aug 2013 says Mr. Zavitz completed the swim in 10 hours and 45 minutes. He exceeded his goal and raised CAN$11,000 for Lions Camp Dorset.

Next year, Mr. Zavitz plans to swim Lake Ontario, a distance of about 52 km (32 miles). To follow Mr. Dorset on Facebook, his page is at Tied Together Swim. To learn more and to make a donation go to tiedtogetherswim.com. The video featured on the website was produced by his recipient Mr. Hunt, who is a filmmaker.


Figure 2. Screenshot of the Tied Together Swim website

A list of camps for children with special medical needs in the United States is available at the Transplant Living website.


Kidney swaps explained

A kidney swap begins with a patient who needs a transplant  and has a willing donor who is healthy but is not blood type or HLA compatible. Through a matching service, called a kidney exchange, they can find another patient-donor pair in the same situation where the donors in each pair match the patient in the other pair (Fig 3a).

Finding pairs that match each other is sometimes difficult. Matching becomes easier if a nondirected donor, that is a person who does not have a patient in mind but just wants to donate a kidney enters the exchange. Then all the matches only have to be one-way (Fig 3b).



Figures 3a and 3b. An example of a kidney swap (top) and kidney chain (bottom). Images by George Taniwaki

The use of kidney swaps  and kidney chains to facilitate kidney transplants is a recent phenomena. The first multihospital kidney chain occurred in the U.S. in 2007 (see Sept 2009 blog post). These kidney swaps are getting more common in the U.S. (see June 2010 blog post) but are still fairly rare outside the U.S.

Canada started up a Living Donor Paired Exchange (LDPE) program in Oct 2010 (see Dec 2010 blog post). It only allows swaps. Chains starting with a nondirected donor are not yet permitted in Canada.

I just saw a link shared by The Living Kidney Donors Network on its Facebook page. The link was to a press release by Donate Life California. In it is a very clever video by David Goldman called “David Got a Kidney.” It is worth a view.


Video still from “David Got a Kidney” Courtesy David Goldman

David is a kidney patient who was one of the participants of a very long kidney chain (28 patients at 19 different transplant centers over a span of about six weeks) facilitated by the National Kidney Registry.


David has an earlier video entitled “David Needs a Kidney” that was featured in a Jan 2013 blog post.


Reading through the press release, I notice that Donate Life California operates a service called Living Donation California. Living Donation California is an information and referral service that promotes living organ donation. It was created as a result of California SB 1395, the “Altruistic Living Donor Registry Act of 2010.” The bill was championed by then Gov. Arnold Schwarzenegger and the late Apple founder Steve Jobs. For more about the bill, read this Jun 2010 blog post.

A recent post on the Living Kidney Donors Network Facebook page contains a link to a Aug 2012 story in the Toledo Blade about an operating room error that led to the irreversible loss of a live donor kidney.


The accident occurred at the University of Toledo Medical Center on August 10. The donor was a man whose intended recipient was his older sister. It appears that the surgery to remove the kidney from the donor was successful. But through some error, the kidney was not properly handled and ended up with the medical waste. The surgeons spent two hours trying to recover it, but ultimately decided not to proceed with the transplant.

This is a tragic event. The emotional trauma being felt by both the patient and the donor is hard to imagine. If you are a potential kidney donor and feel that you may drop out due to this shocking story, I have a few comments that I hope will give you the reassurance to stay in the transplant program at whatever hospital you are at.

First, this is a very rare event, as it should be. There have been about 4,000 live donor transplants conducted so far this year in the U.S. and about 50,000 total in the past decade. I’m not aware of any similar story involving the a live donor kidney rendered medically unusable after removal. (It is common for deceased donor kidneys to not be usable and eventually discarded, but the conditions are quite different.)

Second, there will be an investigation into the cause of this error and recommendations on how to prevent it from happening again. This information will be shared with all transplant centers in the U.S. to improve safety nationwide.

The UTMC transplant program has been voluntarily suspended during the investigation. An outside investigator, Dr. Marlon Levy, the surgical director of the transplant program at Baylor All Saints Medical Center in Fort Worth, will be brought in to review the program. The review will also include officials  from the Organ Procurement and Transplantation Network (OPTN), a nonprofit organization that monitors all transplant programs in the U.S.

In a June 2010 blog post, I mention that most accidents, not limited to the medical field, are caused by system failures not simply an individual mistake. For instance, perhaps a safety checklist or communications checklist wasn’t in place or wasn’t used properly to prevent this error. Unfortunately, the Toledo Blade article names the individual nurses who have been placed on administrative leave, implying they are solely to blame. Reading the comments on the story as well as on the LKDN Facebook page indicates most readers also place blame on the nurses. However, I believe much of the blame should be placed on the administrators, surgeons, and training staff who failed to implement and maintain the safety program.

Finally, the accident at UTMC has immediate impact on a lot of patients now. While the UTMC program is suspended, any kidney patient awaiting a transplant at UTMC will be delayed. Some of these patients may be able to transfer to another hospital (there are nine transplant centers in Ohio), but most will have to wait until the UTMC reopens.

Also, one of the surgeons involved in this accident is Dr. Michael Rees, the founder of the Alliance for Paired Donation, a kidney exchange program frequently mentioned in this blog (for instance, see Nov 2009). Since many of the kidney exchange operations involve UTMC, the temporary suspension of the UTMC program could delay transplants for a lot of patients around the country. Thus, although suspending the UTMC program is an important step to increasing safety, keeping it closed for an extending time would be bad and may lead to patients on the transplant waiting list dying.

In closing, I urge any potential donors who may be having second thoughts about undergoing surgery to not back out now and to remain committed to giving the gift of life.

[Update: The investigation is complete and a report issued. An Oct 2012 blog post describes the findings and changes to be made to the program.]

by George Taniwaki

Patients with end-stage renal disease (ESRD) often wait many years for a transplant. There are currently over 85,000 people in the U.S. waiting for a kidney transplant and the number grows each year. The average wait time is over three years. The mortality rate for those with ESRD on dialysis is over 15% per year, meaning that almost half of the patients die and never get a transplant.

Eliminating the waiting list for kidney transplants is a complex problem. But I see four separate solutions. They are reduce the incidence rate of ESRD, increase the supply of deceased donor organs, increase the supply of live donor organs, and apply new technologies to enhance or replace human organs. These solutions are not mutually exclusive and should each be investigated and instituted by the appropriate organizations. In fact, I don’t believe any one of these solutions will eliminate the list on its own, and so possibly all of them will need to be pursued.

I will illustrate the various pieces of this problem with the four flow charts shown below and then discuss each of the four solution areas in future blog posts. The text in orange boxes represent actions that can be taken. The text in green boxes indicate the intended results of those actions.

Access to healthcare

For blog posts related to patient access to preventative care, patient education on treatment modalities, or dialysis treatment, see entries tagged with Access To Healthcare or Dialysis.

Note that in the right side of Figure 1, educating patients about the advantages of transplant therapy will increase the demand for transplants, which will make the waiting list longer if other steps are not taken to reduce the incidence of ESRD or increase the supply of organs.


Figure 1. Actions that may reduce the incidence of ESRD (left) and increase demand for transplant therapy (right)

Deceased donor transplants

For blog posts related to deceased donor transplants, including patient evaluation and experience, see entries tagged with Deceased Donor.


Figure 2. Actions that may increase supply of deceased donor kidneys

Live donor transplants

For blog posts related to live donor transplants, see entries tagged with Live Donor or Kidney Exchange. (For more on the live donor evaluation process, see entries tagged with Donor Story.)


Figure 3. Actions that may increase supply of live donor kidneys

New technologies

For blog posts related to alternatives to current transplant therapy, see entries tagged with Artificial Organs, Stem Cells, and New Therapies.


Figure 4. New technologies that may someday replace standard transplant therapy

Disclosure note: I am a community member of the Organ Donation Legislative Workgroup in Washington state. I am also a volunteer for several organizations that provide healthcare services to patients with ESRD. However, the opinions in this blog post are my own and do not represent those of any group.

All images by George Taniwaki

[Update1: I modified Figure 3]

[Update2: I added links to tagged blog posts]

This is the final blog entry on solving the problem of getting hospitals to cooperate and allow a national kidney exchange to match all their live donors. You can see part 1 here and part 2 here.


There are several ways to encourage hospitals to submit all their pairs to the exchange rather than withhold some. One mentioned in a paper by Itai Ashlagi and Alvin Roth in Nat. Bur. Econ. Res. Jan 2011 is to use a lottery that rewards hospitals with more matches if they enter their easy-to-match pairs into the exchange. Hospitals that enter more O blood type donors will be rewarded by getting more matches for their O blood type patients. (As noted earlier, currently most transplant centers do not place their matched patient-donor pairs in exchanges. This must change for exchanges to reach their full potential.)

The solution suggested by Mr. Ashlagi and Mr. Roth reduces the number of total transplants compared to full cooperation with no incentive, but produces more transplants than under the current practice of noncooperation.

Some other possible solutions could involve incentives that don’t reduce the total number of transplants. For instance, the exchange could publicize the count of paired matches made for each hospital internally vs through the exchange (basically shaming the hospitals that don’t fully participate). Even if the transplant centers do not reveal the total number of pairs to the exchange, this number is publicly available. Each transplant hospital is required to report the total number of swaps it performs to the United Network for Organ Sharing (UNOS). The exchange knows how many swaps it facilitated. The difference between the UNOS’s count of live unrelated donors and the exchange’s count of pairs entered will be the number of transplants the hospital conducted internally.

Another solution that doesn’t affect the total number of transplants is to reward cooperating hospitals with first choice of donors if there are multiple matches.

Finally, exchanges can do a better job of handling preferences and constraints requested by the participating hospitals. Rather than having a collection of regional exchanges in order to meet the needs of a set of hospitals, a single national exchange can include preferences for maximum shipping time/distance, maximum donor age, minimum and maximum donor kidney size, maximum HLA mismatches, etc. for each hospital and even each patient. It can give preferences to juvenile patients, patients with high cPRA, patients who have been waiting more than six months in the exchange, etc. The exchange can use these constraints to find the favored matches without sacrificing the total number of transplants.


One would expect the kidney exchange market to evolve into a natural monopoly with one exchange gaining all the participants by offering the highest likelihood of a match in the shortest possible time.

However, we are not seeing that at this time because of difficulty in getting exchanges and participating hospitals to work cooperatively and quickly. These problems can be resolved and I expect kidney exchanges to grow until nearly all live donor transplants are mediated through them.

I hope that regional kidney exchanges do not form and instead the problems in the national exchanges are solved. The formation of regional exchanges would split up the pool of potential matches. Finding the easy matches locally and the pushing the hard matches to another pool will lead to suboptimal number of transplants. This is a serious issue because it means some patients will die while waiting for a transplant.

[Disclosure: I do volunteer work for the National Kidney Registry, one of the several exchanges that are the subject of this three-part blog post.]

This is a continuation of yesterday’s blog post on why national kidney exchanges are not reaching their full potential.

In yesterday’s post, we described how a single national kidney exchange would be efficient. By having a large pool of candidates, it will lead to both more matches and faster matches. But we observe some hospitals do not join an exchange. And even hospitals that do join an exchange still perform some or most of their matches in-house. Below are some reasons. Part 3 will outline some solutions.

Hospitals believe they will get more transplants doing swaps in-house

Everybody wants to do what is best for the patients. However, that is hard to know what that is in practice. Hospitals want to do what is best for their own patients, the ones they know and care for. It is difficult for doctors at a single hospital to judge what is collectively best for all the patients in the U.S. One of the problems facing a kidney exchange is that maximizing the number of transplants in the pool may not maximize the number of transplants within a hospital that is a member of the exchange.

Let’s say there are two transplant hospitals A and B. Hospital A has 3 pairs in its pool and can match all 3 of them. Hospital B has 4 pairs and can match 2, for a total of 5 transplants as shown below. Black lines show matches used while orange lines show matches that are not used.


Five transplants when hospitals don’t cooperate. Graphic based on Nat. Bureau Econ. Res.

Now let’s combine the pairs from the two hospitals in an exchange. If we do so, we find we can get a total of 6 transplants as shown in the figure below.


Six transplants when hospitals cooperate. Graphic based on Nat. Bureau Econ. Res.

Hospital B goes from 2 transplants to 4. But notice that Hospital A drops from 3 transplants to 2. The patient in Pair A1 no longer gets a kidney and Hospital A performs one fewer profitable transplant. Hospital B and patients in pair B1 and B2 benefit at the expense of Hospital A and the patient in Pair A1. Thus, Hospital A has an incentive to withhold its pairs from the exchange and perform the swaps in-house.

If every hospital performs all the easy matches in-house, then the exchange will contain fewer pairs. This will make finding matches harder. Even worse, the exchange will only contain hard-to-match pairs, making it even less likely that patients in the exchange will find a match. Hard to match pairs will be patients with O blood type (for more see this Mar 2010 blog post) and patients with high levels of antibodies to human leukocyte antigens (for more see this Feb 2011 blog post.)

Note that most hospitals may not even realize that they are withholding pairs from the exchange. If a patient and donor match (which is likely if the donor is blood type O), the hospital will just proceed with the transplant without even considering entering them into an exchange. By transplanting their easy-to-match O donor pairs directly, they leave the national pools with a surplus of O patients and a shortage of O donors.

Hospitals believe there is less delay doing swaps in-house

Another reason hospitals may prefer to handle swaps in-house is the perceived high administrative cost and delay caused by placing patients in an exchange.

For example, the United Network for Organ Sharing (UNOS is the national organization responsible for the distribution of deceased donor kidneys) has started a pilot program to create a national living donor kidney exchange. It taken over two years to develop a consensus of how to operate the program. Finally, in November of last year it conducted its first match run which found 3 sets of matches. Only one of them was accepted and resulted in 2 transplants. Since then it has not had a single match offer accepted and no further transplants have occurred. (See Jan 2011 blog post for details.)

Hospitals are quickly learning that a majority of offers made by the national exchanges do not lead to a transplant. With a lack of success in a national exchange, hospitals would be negligent to not try to help their patients by conducting matches within their own patient pools or form small regional pools.

Here’s an explanation why I think match offers may not lead to a transplant. Imagine a swap that involves three sets of patients-donor pairs. For each of the three transplants, the surgeon has to approve of the donor. If any one is rejected, then the entire swap fails. Then all transplant pairs require a cross-match test for compatibility. Again, if any one fails or cannot be completed within the required time limit, then the swap fails. Finally, all six surgeries must be scheduled. If any of surgeries cannot be scheduled within the required time windows, then the swap will fail. If each of the 3 step for each of the 3 transplant has a 7% chance of failure, then the cumulative chance of success for a 3-way swap is only about 50 percent (1 – 0.07)^9 = 0.52.

All of the steps above are easier to coordinate if they are conducted within a single hospital. An important key to success for a national exchange is to remind every transplant center how important it is to get the approvals and tests completed in a timely manner and to drive these transplants to completion.

Hospitals believe there are lower medical risks doing swaps in-house

Finally, some hospitals fear that participating in an exchange will expose them to higher risk donors. Each hospital does a very thorough examination of donors prior to accepting them into the transplant program. Accepting a donor that they did not evaluate exposes them to two risks, one real and the other perceived.

Let’s cover the perceived risk first. A surgeon at the transplant hospital probably believes the evaluation of donors done at her hospital is excellent and trusts all members of the transplant team. However, in an exchange, the donor comes from another hospital. The surgeon may not personally know the evaluation team at the donor hospital. She may not be familiar with the evaluation criteria used at that hospital. In fact she may believe that the testing done there may not be  is not as rigorous as its own.

I believe that this concern will be alleviated over time as hospitals become more comfortable with the concept of cross-hospital exchanges. There are only 268 transplant centers in the U.S. and most of them use a very similar criteria when evaluating donors. Even if the hospitals use different criteria for acceptance, the equipment they use are very similar so the test results themselves should be comparable across hospitals.

The real risk is that a patient and her surgeon may be subjected to is that the donor hospital may not be as careful in evaluating a donor in an exchange, knowing that it will not be responsible for the outcome of the transplant. This type of risk is known as moral hazard. It is one of the factors that led to the recent financial crisis. Banks reduced the effort made to ensure mortgages were properly evaluated when they knew they would not be responsible for losses caused by any future loan defaults. This is a real risk and has to be managed. One solution is to make sure a certain percentage of matches made in the national exchange include pairs in the same hospital. This should encourage hospitals to do a good job of evaluating donors, since they won’t know which transplants will remain in-house.

In addition to donor evaluation risk, accepting a kidney from another hospital also entails transportation risk. Performing a transplant completely within a single hospital means that the kidney travels a few feet between the donor and the recipient.

The trauma a kidney undergoes is divided between warm ischemia time (the time it takes from when blood stops flowing to the organ to the time it is packed in ice) and cold ischemia time (the time it takes to transport the chilled organ from donor’s operating room to the recipient’s operating room and reattach it). The warm ischemia time causes the most damage. It will be a few minutes and it won’t differ whether a kidney is recovered within the same hospital as the patient or in a different one. The cold ischemia time for an in-house exchange can be as short as 10 to 15 minutes. However, if the donor operation takes place in New York while the transplant operation is in Los Angeles, the cold ischemia time may be as long as ten hours if there are flight delays.

Some transplant centers will not accept live kidneys that have been transported by air. I believe this is an unnecessary restriction. All transplant centers accept deceased donor kidneys recovered from outside their hospital. These kidneys are often delivered by commercial or charter aircraft, sometimes with cold ischemia times of over 20 hours. (For more on shipping kidneys, see this Dec 2010 blog post and an upcoming blog post.)

The third and final blog post provides ideas to solve these issues.