Wednesday, October 14, 2009

Two little-known facts about organ transplant

by Lydia McGrew
http://www.whatswrongwiththeworld.net/
October 8, 2009

This post will be fairly brief. I hope to write more another time about last year's report by the President's Council on Bioethics (that would be the previous President's council) concerning the determination of death.

Here I just want to highlight two little-known facts that I've become aware of that are very troubling concerning organ procurement practices.

The first fact concerns procurement from patients declared brain dead. Brain death is ostensibly the irreversible cessation of all functions of the entire brain, including the brain stem. That is its legal purport. It must not be confused with being in a so-called "persistent vegetative state." All patients legally declared brain-dead are unable to breathe on their own, whereas patients diagnosed as PVS are usually able to breathe on their own and have at least, as far as anyone knows, brain-stem function.

However, it apparently has been known for quite some time that (some? most? all?) patients declared brain-dead maintain body temperature, though at a somewhat lower-than-normal level and with help from blankets. (See PCBE report, pp. 40, 56, 60.)

In case the relevant bit of human anatomy class has faded into the misty past, body temperature is maintained by the hypothalamus which is...a part of the brain located just above the brain stem.

I have to admit that I fail to understand how anyone could declare in good faith that all the functions of a patient's brain have ceased if a function of the hypothalamus is obviously on-going. A clue may, unfortunately, be found in a passage about which I shall probably have more to say in the PCBE report:

[E]vidence of continued activity of the pituitary gland, or of similar residual brain tissue function in patients diagnosed with “brain death,” is not decisive in determining whether these patients are living or dead.* The question is not, Has the whole brain died? The question is, Has the human being died? This criticism can be leveled perhaps even more sharply at the commonly employed phrase “whole brain death,” which, if taken literally, implies that every part of the brain must be non-functional for the diagnosis to be made. In reality, and somewhat at odds with the exact wording of the UDDA, “all functions of the entire brain” do not have to be extinguished in order to meet the neurological standard under the current application of the law to medical practice. In Chapter Four, we take up the question, “On what grounds might we judge the persistence of certain functions (e.g., ADH secretion by the pituitary gland) to be less important than other functions (e.g., spontaneous breathing)?” (p. 18) [Emphasis added]

Oh. So they didn't mean it. Although it is the activity of the pituitary gland the report is discussing here (the report states [p. 56] that growth has occurred in at least one child declared brain-dead), presumably the authors of the report would say the same about the action of the hypothalamus--that it isn't as "important" as other functions, such as breathing, and hence that it is fine to declare someone brain dead even if his hypothalamus is still working--though such a declaration would be, er, "somewhat at odds with the exact wording" of the Uniform Determination of Death Act.

The second little-known fact is perhaps even more shocking and concerns the other method of organ procurement. In this method, the patient is not declared brain dead. Rather, a ventilator-dependent patient is taken off the ventilator, and doctors wait until he stops breathing naturally. They wait 2 to 5 minutes after breathing and heartbeat stop and declare him dead. Then he is a candidate for organ procurement, which occurs very quickly thereafter so that organs are not damaged by what is known as "warm ischemia."

Most people assume, if they think about non-heart-beating donation at all, that when someone is declared dead because he isn't breathing and his heart isn't beating, that's it. He isn't resuscitated, even if he could be resuscitated, and so he may be declared dead. Even the PCBE (the experts who tried to find out as much as they could before writing their report) assumes this in discussing non-heart-beating donation:

It is important to note that this hypothetical scenario of resuscitating a patient who has been prepared for a controlled DCD procurement is merely a “thought experiment.” In reality, attempting to revive such a patient would be ruled out ethically because the practice of controlled DCD is premised on the assumption that the individual’s family has decided to allow withdrawal of life-sustaining interventions and would, therefore, want to abstain from any efforts to prevent the patient’s death (perhaps by consenting to a “do not resuscitate” order). For this reason, many have argued that the word “irreversible” in this context should be understood in a weaker sense than that spelled out above: It should be understood to mean “cessation of circulatory and respiratory functions under conditions in which those functions cannot return on their own and will not be restored by medical interventions.” (p. 84)

It is understandable that even this argument might bother some people. The obvious philosophical question that arises is this: Why is someone's loss of breathing and respiration considered irreversible because of what someone else has decided not to do? Should not irreversibility be an actual medical determination, not a combination of a medical determination with an intention on the part of people around?

But that concern almost pales into insignificance when one encounters the following quotation from an article about non-heart-beating donation. (I mentioned this in another thread.)

Artificial support of circulation with cardiopulmonary bypass and reintubation for lung ventilation are required for organ viability in donors. The donation-related procedures can resuscitate (reanimate) organ donors during procurement, which requires pharmacological agents (chlorpromazine and lidocaine) and/or occlusion of coronary and cerebral circulation for suppression...

Translation: The possibility of resuscitating patients declared dead under NHBD protocols is not merely a "thought experiment" but very real. First they take the vent-dependent patient off the ventilator and let him stop breathing which causes his heart to stop. Then they wait whatever number of minutes their hospital's protocol calls for--somewhere between two and five minutes. They declare him dead. Then they start the ventilator back up again to keep the organs fresh during procurement. But because it is so soon after the cessation of breathing and heartbeat, they have a very real worry that they may resuscitate the "dead" patient. So they have to block off circulation to his brain or else dope him up to prevent him from "coming to life again."

I wonder how many people know that about NHBD? I wonder how many people would be rightly creeped out by it if they did? It's very obvious from this that NHBD is by no means an ethical alternative to organ procurement from patients declared brain-dead. Indeed, waiting for the patient to be declared brain-dead is arguably applying a more rigorous standard for death, though one which raises all the questions about diagnosis to which I've been alluding.

It is time for conservative ethicists to reconsider seriously their endorsement of vital organ donation. If there is no ethical way to do it, that should be the end of the discussion. Organ procurement is not an absolute imperative.

Posted by Lydia McGrew on October 8, 2009 3:58 PM Del.icio.us
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