MEDICAL TOPIC:
Timing of Referral
for Lung Transplantation
Mortality in most cystic fibrosis patients is related to chronic
progressive pulmonary disease. Lung transplantation is a valuable
therapeutic option, which may be offered in such cases. The
timing of referral for lung transplantation involves a complex
decision involving patient, physician and the family. On the
one hand too early transplantation is undesirable since this
intervention may involve many serious complications, while
on the other hand the candidate's condition must be maintained
functionally suitable for transplantation.
The average waiting time for suitable cadaveric lung donation
is 2 years. However, it may vary depending upon factors such
as a candidate's blood type, height, the length of the waiting
list and the awareness of organ donation in the candidate's
country. The lack of readily available donor organs compels
physicians to refer patients for transplantation a long time
before it becomes critical. Since lung transplantation is
a major surgical procedure involving morbidity and mortality,
premature referral should be avoided.
"For the
patient and family, referral for transplantation
has vast psychological implications."
For the patient and family, referral for transplantation
has vast psychological implications. The life-threatening
nature of the illness is paradoxically both acknowledged as
well as defended from the time of diagnosis. The chronic,
slow and gradual deterioration of the illness enables a fairly
stable psychological adaptation while patients employ a variety
of defense mechanisms such as denial and suppression. The
offer and proposal of lung transplantation to a patient by
the physician, conveys the current appraisal of the medical
team that the patient's life is imminently threatened and
is a painful reminder of the lethality of CF. These tidings
might undermine the psychological defensive structure and
set into motion a reappraisal of the seriousness of their
condition and may arouse anxiety and depression. However,
it should be borne in mind that as a result of a late referral
, 15-40% of listed patients die while awaiting a suitable
donation.
"Living donor
lung transplantation is now an acceptable option
"
Living donor lung transplantation is now an acceptable option
which offers an alternative for patients with a life expectancy
of less than a few months who would have otherwise died. In
addition, it was found that these patients develop less bronchiolitis
obliterans than patients who underwent cadaveric transplantation.
However, this option depends on the existence of potential
donors and involves many legal and ethical issues; therefore
living donor transplantation is suitable only for selected
patients, while others have to wait for cadaveric donation.
"Two strategies
have been proposed for using FEV1 as a marker
"
Many of our patients with FEV1 of 30% (the current criteria
for transplantation) survive for periods longer than 2 years,
and most of them are fully active. Therefore, it is unjustified
to place them on the transplantation candidate list based
on FEV1 alone. Currently, FEV1 is one of the clinical markers
used to determine referral for lung transplantation. Two strategies
have been proposed for using FEV1 as a marker: The first approach
uses a threshold value of FEV1; Kerem recommend a FEV1 value
<30%, while Robinson suggested that lung transplantation
should be considered in a young CF patient whose best FEV1
in a 6 month period is <50%.
The second approach uses the rate of decline in FEV1 values,
which was found by Milla to be a better parameter than a cutoff
value of FEV1 of <30% predicted, to identify patients at
high risk of death. The results of a study which have been
conducted by us recently, indicate that the rate of change
in FEV1 values as well as young age are efficient prognostic
factors to predict mortality in CF patients. Kerem had also
found that for a given FEV1, patients under the age of 18
years had a higher 2-year mortality rate than their counterparts.
CONCLUSION
Taking all this data into account, we suggest a refining
of the currently used criteria; patients with FEV1< 30%
who have rapidly declining FEV1 values especially when they
are younger than 15 years should be referred for lung transplantation.
Arie Augarten, M.D.
National CF Center
The Chaim Sheba Medical Center
Tel-Hashomer, Israel 52621
E-Mail: augarten@post.tau.ac.il
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