扩展标准供体在高风险肺移植受体中的应用

Application of Extended Standard Donors in Recipients of High-Risk Lung Transplantation

摘要: 背景：扩展标准供体(extended criteria donor, ECD)能够缓解肺移植供体短缺这一现状并扩大供体库。然而，其在高风险肺移植受体中的短期及长期可用性尚不清楚。方法：在这项回顾性研究中，对2005年5月13日至2022年3月4日接受肺移植的肺分配评分(lung allocation score, LAS) ≥ 70分的成年患者在器官共享联合网络(United Network for Organ Sharing, UNOS)数据库进行了查询。ECD由一个或多个与标准供体不同的条目定义：年龄 ≥ 55岁，PaO₂/FiO₂ ≤ 300 mmHg，吸烟 ≥ 20包年，糖尿病诊断，或支气管镜检查见脓性分泌物。受体被分为标准供体(standard criteria donor, SCD)组和ECD组，并评估短期和长期生存率以及术后事件。结果：在4123例肺移植中，ECD组的5年总生存率明显更低(p = 0.02)；SCD组和ECD组的1年总生存率没有统计学差异(p = 0.56)。ECD组的住院时间更长(中位数25.0天vs. 22.0天；p < 0.001)，术后透析可能性更大(14.9% vs. 12.6%; p = 0.04)；但无论是术后呼吸机支持>48小时、再次插管率、移植后72小时内的3级原发性移植物功能障碍(primary graft dysfunction, PGD)发生率、急性排斥反应还是30天、90天死亡率都没有发现显著差异。用作扩展标准的五个供体因素中，供体吸烟 ≥ 20包年能够独立预测1年(HR 1.36, 95%CI 1.05~1.78; p = 0.02)及5年(HR 1.29, 95%CI 1.07~1.54; p = 0.007)死亡风险，其余因素与生存无明显相关性。结论：对于高风险受体来说，SCD和ECD组在术后早期生存或不良事件方面没有显著差异，而远期生存并不令人满意。将ECD肺用于高风险受体仍需谨慎评估，并加强对于术后远期不良事件的管理。需要进一步的研究以确定特定供体因素影响高风险受体的潜在机制。

Abstract: Background: Extended criteria donor (ECD) alleviates the shortage of donor lungs and expands the donor pool. However, its short-term and long-term availability in high-risk lung recipients remains unclear. Methods: In this retrospective study, adult patients with lung allocation score (LAS) ≥ 70 who underwent lung transplantation between May 13, 2005, and March 4, 2022 were queried in the United Network for Organ Sharing (UNOS) database. ECDs were defined by one or more items at variance from standard criteria: age 55 years or more, PaO₂/FiO₂ 300 or less, smoking 20 pack-years or more, diabetes, or purulent secretions upon bronchoscopy. Recipients were divided into the standard criteria donor (SCD) group and the ECD group, and assessed for short- and long-term survival and postoperative events. Results: Among 4123 records, the 5-year overall survival rate of the ECD group was significantly lower (p = 0.02); the SCD and ECD groups showed no differences in 1-year (p = 0.56) survival. Compared with the SCD group, the ECD group had a longer hospital stay (median 25.0 days vs. 22.0 days; p < 0.001) and was more likely to experience postoperative dialysis (14.9% vs. 12.6%; p = 0.04). No significant differences were found in 30-day, 90-day mortality and other postoperative outcomes before discharge, whether in rate of ventilator support for >48 hours or reintubation, incidence of grade 3 primary graft dysfunction (PGD) 72 hours posttransplant, or acute rejection. Among the five donor factors used as extended criteria, donor smoking ≥ 20 pack years independently predicted 1-year (HR 1.36, 95%CI 1.05~1.78; p = 0.02) and 5-year (HR 1.29, 95%CI 1.07~1.54; p = 0.007) mortality risk, while other factors were not significantly associated with recipient survival. Conclusions: For high-risk recipients, there was no significant difference in early postoperative survival or adverse events between the SCD and ECD groups, whereas long-term survival was not satisfactory. The use of ECD lungs for high-risk recipients still requires careful evaluation and strengthened management of postoperative long-term adverse events. Further studies are needed to identify the potential mechanisms by which specific donor factors affect high-risk recipients.