Prognostic factors for lung transplant recipients focusing on age and gender: the Japanese lung transplantation report 2022

Effect of revised organ transplant law in Japan on lung transplantation

PURPOSE

To investigate how revision of the organ transplant law in Japan affected lung transplantation in this country.

METHODS

Lung transplant candidates registered between January, 2000 and December, 2009 were designated as the pre-revision group (n = 396) and those registered between January, 2011 and December, 2020, as the post-revision group (n = 1326). Both groups were analyzed retrospectively using data collected by the Japanese Society of Lung and Heart-Lung Transplantation.

RESULTS

The number of patients who underwent brain-dead donor lung transplantation (BDLT) increased significantly after the law amendment (32.2 vs. 13.8%, p < 0.01). The median waiting time for BDLT was significantly reduced (708 days vs. 1163 days, p < 0.01) and the mortality rate while waiting for BDLT improved significantly after the law amendment (33.1 vs. 42.6%, p < 0.01). In the post-revision group, 18 pediatric patients underwent BDLT. The 5-year survival rates after BDLT were comparable between the groups (73.5% in the pre-revision group vs. 73.2% in the post-revision group, p = 0.32).

CONCLUSIONS

The organ transplant law revision shortened the waiting time for BDLT significantly and decreased the mortality rate while waiting for BDLT. The posttransplant outcomes in Japan remained favorable throughout the study period.

Baseline lung allograft dysfunction after bilateral deceased-donor lung transplantation: A single-center experience in Japan

BACKGROUND

Baseline lung allograft dysfunction (BLAD) refers to a condition in which a lung transplant recipient does not achieve normal pulmonary function (i.e., forced expiratory volume in 1 s or forced vital capacity of <80% of predicted values). Although BLAD is reportedly associated with a poor prognosis, the condition has not been examined in Japanese patients.

METHODS

In this study, we retrospectively examined 38 Japanese adults who underwent bilateral lung transplantation from 2015 to 2022 in a single center.

RESULTS

Twenty-one (55%) patients met the criteria for BLAD. No significant differences were found in recipient or donor factors between the BLAD and non-BLAD groups, but the donor-recipient ratio of the predicted vital capacity was lower in the BLAD group (p = 0.009). The intensive care unit length of stay, ventilator duration, and blood loss during transplant surgery were significantly higher in the BLAD group (p < 0.05). No significant difference was found in survival. The median observation period was significantly shorter in the BLAD than non-BLAD group (744 vs.1192 days, respectively; p = 0.031). The time to reach the normal threshold of pulmonary function after lung transplantation varied among the patients, ranging from 6 months to 4 years.

CONCLUSIONS

The characteristics of these Japanese patients with BLAD were similar to those of other patients in previous reports. The effects of the observation period and donor-recipient age discrepancy on BLAD require further exploration.

Single lung transplantation using a lung graft from a donor whose contralateral lung is not suitable for lung transplantation

OBJECTIVE

This study aims to compare the post-transplant survival of untwinned single lung transplantation (SLT) to twinned SLT. In untwinned SLT, the contralateral lung is judged unsuitable for transplantation and might affect the lung graft within the donor body and recipient survival after SLT.

METHODS

A retrospective analysis was conducted on 84 SLT recipients at our center, divided into untwinned SLT and twinned SLT groups. The demographics of donors and recipients, surgical characteristics, complications, mortality, and survival rates were compared.

RESULTS

There were no significant differences in recipient and donor demographics between the two groups. Surgical characteristics showed no significant differences. Microbiological findings of the transplanted lungs indicated a low incidence of positive cultures in both groups. 3-month to 1-year mortality and overall survival rates were comparable between the two groups.

CONCLUSION

At our institution, both untwinned and twinned SLT procedures exhibited excellent survival rates without significant differences between the two procedures. The favorable outcomes observed may be associated with the strategic advantages of Japan's MC system and the diligent management of marginal donor lungs although this requires further investigation to elucidate the specific contributory factors.

Living-donor lobar lung transplantation

Living-donor lobar lung transplantation (LDLLT) is indicated for critically ill patients who would not survive the waiting period in the case of severe brain-dead donor shortage. It is essential to confirm that potential donors are willing to donate without applying psychological pressure from others. In standard LDLLT, the right and left lower lobes donated by 2 healthy donors are implanted into the recipient under cardiopulmonary support. LDLLT can be applied to various lung diseases including restrictive, obstructive, infectious, and vascular lung diseases in both adult and pediatric patients if size matching is acceptable. Functional size matching by measuring donor pulmonary function and anatomical size matching by 3-dimensional computed tomography volumetry are very useful. When 2 donors with ideal size matching are not available, various transplant procedures, such as single lobe, segmental, recipient lobe-sparing, and inverted lobar transplants are valuable options. There seems to be immunological advantages in LDLLT as compared to cadaveric lung transplantation (CLT). Unilateral chronic allograft dysfunction is a unique manifestation after bilateral LDLLT, which may contribute to better prognosis. The growth of adult lung graft implanted into growing pediatric recipients is suggested by radiologic evaluation. Although only 2 lobes are implanted, postoperative pulmonary function is equivalent between LDLLT and CLT. The long-term outcome after LDLLT is similar to or better than that after CLT. The author has performed 164 LDLLTs resulting in 71.6% survival rate at 10 years. All living-donors returned to their previous life styles. Because of possible serious morbidity in donors, LDLLT should be applied only for critically ill patients.