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