Melanie Cole (Host): Welcome to the podcast series from the specialists at Penn Medicine. I'm Melanie Cole. And today, we're discussing managing high acuity and DCD cases. Joining me is Dr. Peter Abt. He's the Surgical Director of Liver Transplant at Penn Medicine. Dr. Abt, thank you so much for joining us today. I'd like you to start by telling us what is donation after circulatory death or DCD?

What's the difference between DCD and donation after brain death or DBD?

Dr Peter Abt: Sure. In the United States, there are two ways to be declared legally deceased. One is the absence of blood flow to the brain, and that has sort of been the traditional way in which organ donation has taken place since the late 1970s. Donation after circulatory death is what most of us would think of death.

That is, your heart stops beating and you stop breathing. The individual who is a donation after circulatory death donor is generally somebody who's had a severe neurologic injury, maybe a stroke, or they had a heart attack, and they didn't get enough blood flow to their brain, but they don't meet brain death criteria.

However, in the minds of the caregiver for that individual, it might be the physicians, their family members, their view is that there's no hope of meaningful recovery, and they've decided to withdraw care from that individual. That doesn't mean that that individual can't donate their organs.

What it means is though they withdraw care, they remove them from the ventilator, and if they pass away in enough time, that is, if their heart stops beating in enough time and they stop breathing, then they can potentially be an organ donor

Melanie Cole (Host): Okay. So this is a really, really interesting topic then. Who decides when life support is withdrawn? Is this the family with a certified physician? How does that process work?

Dr Peter Abt: it's a discussion between the physicians taking care of that individual and the family, the loved ones of that individual. If they believe that this individual is not going to have a meaningful recovery, that is maybe they'll be on a ventilator forever, then they may decide to withdraw care.

And so it's a group decision made with the loved ones and with the physician. And ultimately, it's the patient's family that is responsible for making that determination.

Melanie Cole (Host): And is that when the discussion of donation comes up? Has that come up in an earlier discussion when we think of donation after circulatory death versus the DBD? When does the donation part of the conversation happen?

Dr Peter Abt: The donation discussion comes up after the decision to remove care. We don't want to have conflict in making the organ, donation decision in conjunction with the decision to withdraw care. You wanna have these as separate decisions. Once the family has decided they're going to withdraw care, generally, they're approached about organ donation

Melanie Cole (Host): So I think one of the questions that so many people, whether they're provider or patient families have, Dr. Apt, is how do you know the patient is truly deceased before surgery starts? Is the patient alive when being transferred to the operating room for withdrawal of life support? How does that process all work?

Dr Peter Abt: Yeah. So withdrawal of life support could take place in the operating room, or it could take place in the intensive care unit or in a room outside of the operating room. And the person making the decision whether that individual has passed away is completely independent from the organ donation team and the decision to proceed with organ donation.

So this is generally a critical care doctor or an anesthesiologist who is responsible for providing comfort care while that individual is going through the dying process. So the organ procurement organization, the transplant surgeons have nothing to do with the determination of death in the potential donor.

Melanie Cole (Host): Thank you for clearing that up. Now, is there organ specificity when we're talking about DCD? Which organs can you safely recover using this?

Dr Peter Abt: Nowadays, most organs can be recovered successfully from a donation after circulatory death donor. That would include kidneys, liver, heart, lung, and pancreas.

Melanie Cole (Host): Doctor, what is warm ischemia and why is this sometimes an issue with DCD organs?

Dr Peter Abt: What happens when someone is removed from a ventilator and care is withdrawn? Their circulatory status slowly decreases, so their blood pressure goes down, the oxygen levels in their blood goes down. And so their organs aren't being perfused with blood and oxygen and nutrients as well as they would've been when they were being ventilated and were being taken care of.

And so organs become ischemic. the cells become acidotic. A lot of different changes occur within the cells, so the organs themselves, to some respect, suffer a bit while the dying process is occurring. And that is what we call warm ischemia.

Melanie Cole (Host): Dr. Abt, how do you keep the organs healthy when you don't have that circulation? I'd like you to speak about a few of the techniques that you have and one fascinating one, which is normothermic regional perfusion and how that changes the use of DCD in these populations.

Dr Peter Abt: Yeah. So there's been a real revolution in the use of donation after circulatory death donors in the last couple of years. We've learned that if you restore circulation to the organs, then they actually have much better outcomes. And this can be done by circulating the donor's blood within their blood system through pumps after they're declared deceased.

And so we use the donor's own blood, and we warm it up, and we provide it with oxygen, and that helps to preserve and restore the health of those organs. Another way that this can be done is those organs can be removed quickly and then placed on external pumps with blood and oxygen. And this again helps to preserve and to some extent restore the function of the organs.

Melanie Cole (Host): Yeah, that's really so interesting, the technology. It's a very exciting time in your field, Dr. Abt. And how does the expected function of DCD organ compare to an organ from a DBD donor?

Dr Peter Abt: in the past, at least with livers, the outcome of the liver from a DCD organ compared to a brain-dead donor was inferior. However, with these different perfusion techniques, the outcomes for DCD livers are essentially the same as those from brain-dead donors. We know the kidneys that undergo perfusion have a better initial function than they had in the past prior to these perfusion techniques.

And we've also been able to expand the use of hearts and lungs that were rarely used in the past with donation after circulatory death

Melanie Cole (Host): Are there any patients for whom DCD has shown greater benefit or graft survival by comparison to the traditional DBD?

Dr Peter Abt: No, the outcomes aren't better. They’re, at least in liver and kidney, they're relatively equivalent.

Melanie Cole (Host): Dr. Apt, I'd like you to give us a summary now for other providers that are looking at donation after circulatory death and explaining to their patients or doing their own initiatives on this. What would you like them to take away from this episode today?

Dr Peter Abt: I think the big message is that donation after circulatory death has been a real game-changer in the US organ donation system. We are now obtaining many more organs than we had in the past when we just had donation after brain death. And so this provides our patients with greater opportunities for transplantation, which is just really wonderful.

Melanie Cole (Host): Well, it certainly adds another avenue. And thank you so much, Dr. Apt, for joining us today and sharing your expertise. To refer your patient, please call our 24/7 provider-only line at 877-937-PENN, or you can submit your referral via our secure online referral form by visiting our website at pennmedicine.org/refer.

That concludes this episode from the specialists at Penn Medicine. I'm Melanie Cole.