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Ethical
Considerations of Hand Transplantation—Should
we give them a hand?
While the prospect of replacing an amputated hand with composite tissue
allotransplantation has generated much interest and excitement in the
medical community as well as general public, some have questioned the
ethical validity of such a treatment. As a treatment, hand transplantation
offers no prolongation of life, yet comes with the risk of death, casting
doubt on whether this procedure upholds the principle of primum non nocere
(first do no harm). What the procedure does have to offer is the potential
for an improved quality of life for those living with amputations, a potential
which has yet to be proven conclusively. As with many other innovative
and experimental procedures, the issues of scientific validity, risk/benefit
ratio, and patient/donor consent must be considered in determining whether
hand transplantation should be accepted as a valid form of treatment.
Scientific Basis for Hand Transplantation
Hand transplantation does not involve any novel surgical techniques. The
process of attaching a hand to the human body had already been established
through the successful practice of limb replantation. The novelty of hand
transplantation lies in the fact that an allograft is used instead of
an autograft, leading to issues of rejection and immunosuppression. Researchers
pursuing hand transplantation were encouraged by the fact that all components
of the hand (including tendons, skin and muscle) had already been successfully
transplanted individually into humans and have shown prolonged survival.
Full limb transplants in animal studies, however, did not prove as promising.
In experiments done on baboons and rhesus monkeys, only two out of 23
transplants were rejection free after 200 days. It should be noted that
these studies used cyclosporine as the immunosuppressant, which has since
been generally replaced by more effective agents. A study with pigs utilizing
more modern immunosuppressants such as mycophenolate mofetil (MMF) and
FK-506 found that five of nine subjects survived without rejection for
90 days, at which point the study was terminated. Even when rejection
did not occur, complications of the immunosuppression treatment such as
pneumonias and septic arthritis resulted. While 90 days without rejection
is not a failure, it certainly does not provide much insight into the
long-term survival of such grafts, leading some to question whether the
treatment is ready to be tried on humans. Ready or not, there are currently
twenty human patients who have received hand transplantations, 19 of which
remain in good health (the longest survival is over three years). These
human successes have generated much positive publicity and have been used
by some researchers as justification for further human experimentation.
Still, three years does not represent long-term survival, and others have
proposed a moratorium on human hand transplantation until the current
human studies and more animal studies prove the potential for long-term
success.
Potential Risks
The risks of hand transplantation are similar to the risks for other forms
of organ transplantation followed by immunosuppression. The potential
complications of prolonged immunosuppression include increased risk of
infection, increased risk of malignancy, and toxicity of immunosuppression
leading to nephrotoxicity, neurotoxicity, gastrointestinal toxicity and
diabetes. Eighty percent of organ transplants result in infection, which
is the cause of 40% of post-transplantation deaths. In addition, the risk
of cancer following kidney transplantation, which is similar to hand transplantation
in the dosage of immunosuppression used, increases 4-18%. While the recipients
of hand transplantation would be put on similar dosages of immunosuppressants,
it should be noted that unlike many vital organ transplant recipients,
the recipients of hand transplantation are likely to be healthy at the
start of treatment. In addition to the risks associated with immunosuppression,
hand transplantation carries the risk of failure necessitating re-amputation.
A transplanted kidney has a ten-year survival rate of only 40-50% with
a half-life of 7.5-9.5 years. There is little reason to believe that a
transplanted hand, with its highly antigenic skin component, will survive
much better than a kidney. Thus, immunosuppressant toxicity, increased
susceptibility to infection and malignancy, and the potential for graft
failure all pose substantial risks for a patient seeking hand transplantation.

Potential Benefits
Although hand transplantation offers no life-saving ability, its benefits
can be measured in the improved quality of life of its recipients. Factors
to gauge the success of a transplant include the revascularization of
the limb without rejection, the return of functionality, sensation, and
proprioception, and the acceptance of the new hand as a natural body part.
With the exception of the first hand transplant case, in which the recipient
required re-amputation of the transplant due to noncompliance with the
rehabilitation and immunosuppression therapy, all subsequent recipients
have reported high satisfaction, low morbidity, and no mortality. In the
two U.S. cases conducted at the Jewish Hospital in Louisville, Kentucky,
the recipients regained movement within one week, and temperature, pain
and pressure sensation by the first year. The first Louisville recipient
can localize touch on the thumb, ring, and small fingers (middle and index
fingers are reversed). Both recipients (at 36 months and 12 months post
surgery) can tie shoelaces, dress themselves, turn the pages of a book,
throw a ball, and write. The Carroll Test, a measure of hand function
utilizing 33 tasks scored by two independent observers, found that the
recipients of hand transplants showed more functionality than those with
prosthetic devices. In addition, the Carroll Test scores for recipients
of hand transplantation mirrored the early scores of recipients of hand
replantation.

The Risk-Benefit Ratio
Hand transplantation carries with it many of the same life-threatening
risks of vital organ transplantation, but without the life-saving or life-prolonging
benefits that other such procedures offer. The question that remains is
whether the potential benefits of hand transplantation outweigh the potential
risks. This question cannot be easily answered in an objective manner,
and certain individuals may have different motives for drawing their own
conclusions. Certain researchers, for example, may be motivated by the
thrill of being the frontrunners in an innovative field. Certain patients,
on the other hand, may be motivated by an uninformed hope for a miracle
treatment. Unlike prescription drugs, new and experimental surgical procedures
do not require approval from a body such as the FDA. Instead, patient
autonomy has been the legal precedent, allowing such decisions to be made
by the patients themselves in giving their informed consent, enabling
them to decide based on their own values whether to proceed. The improved
quality of life offered by a hand transplant is a highly subjective value;
a new hand may mean different things to different people. However, with
a complex and experimental procedure such as hand transplantation, some
remain skeptical about whether the patients’ consent is truly informed.
In order for patients to give their informed consent, it is vital that
they have a good understanding of the potential risks of the procedure,
a realistic depiction of the possible benefits, and knowledge of alternative
treatments. In order to achieve this, many have proposed the use of an
independent patient’s advocate to serve as a mediator between the
patient and the physicians. Even with patient consent, however, surgeons
are held by the principle of primum non nocere to not operate unless they
feel that the patient will benefit. In order to assure this, researchers
must clear their procedures with an Institutional Review Board at the
local level and should be open to peer review by the surgical societies
at the national level. While there is strong evidence supporting the risks
associated with immunosuppression, opinion about the benefits of hand
transplantation remains inconclusive. A poll of senior hand surgeons found
that 21 out of 23 would not personally undergo hand transplantation for
a unilateral amputation. The benefits of this procedure have to be further
proven before it will gain wide acceptance.
Psychological Effects of Hand Transplantation
The hands are among the most expressive parts of the human body and play
an important role in body image and sense of identity. The psychological
state of potential recipients must be taken into account when deciding
who should get a hand transplant. Potential recipients must be able to
deal with the psychological assimilation of a foreign hand as their own,
as well as the risk of losing their hand for a second time due to rejection
or failure. The recipient of the first hand transplant had falsified his
story of hand injury and was subsequently noncompliant with his immunosuppression
and rehabilitation program leading to graft rejection. In order to avoid
such situations in the future, it has been proposed that potential recipients
undergo psychiatric evaluation of their social history, history of compliance
with medical treatment, emotional and cognitive preparedness for transplantation,
and decision-making capacity. In addition, assessments should be made
of their body-image adaptation after amputation, impact of amputation
on their identity and relationships, level of adjustment to hand loss,
and conception of what receiving a donor hand would mean. Qualities indicating
a good candidate for hand transplant are a history of good psychological
adjustment, lack of psychiatric comorbidity, and good quality of social
support. The psychological importance of the hand in the perception of
body image can also be evaluated at the level of the donor. In the donation
of hands, the symbolic wholeness of the donor body is compromised. Realizing
the importance of maintaining bodily integrity, the first team to transplant
a hand attempted to restore the appearance of the cadaveric donor through
the use of prosthesis. At this experimental stage, it is unclear whether
this factor will make it difficult to gain consent for the donation of
human hands. In its search for participants, the Jewish Hospital received
some offers from parents who were willing to donate one of their own hands
for children who had lost a hand to amputation, but cadaveric donors were
used in both cases.
For some, the answers provided about the validity and potential benefits
of human hand transplantation do not justify further experimentation.
Due to the non-vital nature of the procedure, the urgency for making the
treatment available now is lessened. It has been proposed that the procedure
should be put on hold until better and safer forms of immunosuppressants
are developed, or until more conclusive evidence on the benefits and viability
of the grafts are accumulated from the current trials. At the same time,
there are many patients who are ready and willing to face the current
risks in order to receive a new hand. In the end, open and public discussion
and analysis must find a balance between caution and innovation in order
to determine whether this experimental procedure will proceed
.
Sources:
Breidenbach W. A position statement in support of hand
transplantation. J Hand Surg 2002; 27:760-70
Cooney W. Hand Transplantation—Primum Non Nocere. J Hand Surg
2002; 27:165-8
Dickenson D, Widdershoven G. Ethical Issues in Limb Transplants. Bioethics
2001; 15:110-24
Jones N. Concerns about human hand transplantation in the 21st century.
J Hand Surg 2002; 27:771-87
Klapheke M, Marcell C, Taliaferro G, Creamer B. Psychiatric Assessment
of Candidates for Hand Transplantation. Microsurgery 2000; 20:453-57
Simmons P. Ethical Considerations in Composite Tissue Allotransplantation.
Microsurgery 2000; 20:458-65
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