Lung Transplantation with Controlled Donation after Circulatory Death Donors

Ex vivo lung perfusion in donation after circulatory death: A post hoc analysis of the Normothermic Ex Vivo Lung Perfusion as an Assessment of Extended/Marginal Donors Lungs trial

OBJECTIVE

Donation after circulatory death (DCD) donors offer the ability to expand the lung donor pool and ex vivo lung perfusion (EVLP) further contributes to this ability by allowing for additional evaluation and resuscitation of these extended criteria donors. We sought to determine the outcomes of recipients receiving organs from DCD EVLP donors in a multicenter setting.

METHODS

This was an unplanned post hoc analysis of a multicenter, prospective, nonrandomized trial that took place during 2011 to 2017 with 3 years of follow-up. Patients were placed into 3 groups based off procurement strategy: brain-dead donor (control), brain-dead donor evaluated by EVLP, and DCD donors evaluated by EVLP. The primary outcomes were severe primary graft dysfunction at 72 hours and survival. Secondary outcomes included select perioperative outcomes, and 1-year and 3-years allograft function and quality of life measures.

RESULTS

The DCD EVLP group had significantly higher incidence of severe primary graft dysfunction at 72 hours (P = .03), longer days on mechanical ventilation (P < .001) and in-hospital length of stay (P = .045). Survival at 3 years was 76.5% (95% CI, 69.2%-84.7%) for the control group, 68.3% (95% CI, 58.9%-79.1%) for the brain-dead donor group, and 60.7% (95% CI, 45.1%-81.8%) for the DCD group (P = .36). At 3-year follow-up, presence observed bronchiolitis obliterans syndrome or quality of life metrics did not differ among the groups.

CONCLUSIONS

Although DCD EVLP allografts might not be appropriate to transplant in every candidate recipient, the expansion of their use might afford recipients stagnant on the waitlist a viable therapy.

Controlled donation after circulatory death lung transplantation: Results of the French protocol including in situ abdominal normothermic regional perfusion and ex vivo lung perfusion

BACKGROUND

The French national protocol for controlled donation after circulatory determination of death (cDCD) includes normothermic regional perfusion (NRP) in case of abdominal organ procurement and additional ex-vivo lung perfusion (EVLP) before considering lung transplantation (LT).

METHODS

We made a retrospective study of a prospective registry that included all donors considered for cDCD LT from the beginning of the program in May 2016 to November 2021.

RESULTS

One hundred grafts from 14 donor hospitals were accepted by 6 LT centers. The median duration of the agonal phase was 20 minutes [2-166]. The median duration from circulatory arrest to pulmonary flush was 62 minutes [20-90]. Ten lung grafts were not retrieved due to prolonged agonal phases (n = 3), failure of NRP insertion (n = 5), or poor in situ evaluation (n = 2). The remaining 90 lung grafts were all evaluated on EVLP, with a conversion rate of 84% and a cDCD transplantation rate of 76%. The median total preservation time was 707 minutes [543-1038]. Seventy-one bilateral LTs and 5 single LTs were performed for chronic obstructive pulmonary disease (n = 29), pulmonary fibrosis (n = 21), cystic fibrosis (n = 15), pulmonary hypertension (n = 8), graft-versus-host disease (n = 2), and adenosquamous carcinoma (n = 1). The rate of PGD3 was 9% (n = 5). The 1-year survival rate was 93.4%.

CONCLUSION

After initial acceptance, cDCD lung grafts led to LT in 76% of cases, with outcomes similar to those already reported in the literature. The relative impacts of NRP and EVLP on the outcome following cDCD LT should be assessed prospectively in the context of comparative studies.

Outcomes Of Lung And Liver Transplantation After Simultaneous Recovery Using Abdominal Normothermic Regional Perfusion In Donors After The Circulatory Determination Of Death Versus Donors After Brain Death

Normothermic regional perfusion (NRP) in controlled donation after the circulatory determination of death (cDCD) is a growing preservation technique for abdominal organs that coexists with the rapid recovery of lungs. We aim at describing the outcomes of lung transplants (LuTx) and liver transplants (LiTx) when both grafts are simultaneously recovered from cDCD donors using NRP, and compare them to donation after brain death (DBD). All LuTx and LiTx meeting these criteria during January-2015 to December-2020 in Spain were included in the study. Simultaneous recovery of lungs and livers was undertaken in 227 (17%) cDCD with NRP and 1,879 (21%) DBD donors (p<0.001). Primary graft dysfunction grade-3 within the first 72hours was similar in both LuTx groups (14.7% cDCD vs. 10.5% DBD;p=0.139). LuTx survival at 1 and 3years was 79.9% and 66.4% in cDCD, vs. 81.9% and 69.7% in DBD (p=0.403). The incidence of primary non-function and ischemic cholangiopathy was similar in both LiTx groups. Graft survival at 1 and 3years was 89.7% and 80.8% in cDCD vs. 88.2% and 82.1% in DBD LiTx (p=0.669). In conclusion, the simultaneous rapid recovery of lungs and preservation of abdominal organs with NRP in cDCD donors is feasible, and offers similar outcomes in both LuTx and LiTx recipients to transplants using DBD grafts.

Expanding the Lung Donor Pool: Donation After Circulatory Death, Ex-Vivo Lung Perfusion and Hepatitis C Donors

"Organ shortage remains a limiting factor in lung transplantation. Traditionally, donation after brain death has been the main source of lungs used for transplantation; however, to meet the demand of patients requiring lung transplantation it is crucial to find innovative methods for organ donation. The implementation of extended donors, lung donation after cardiac death (DCD), the use of ex-vivo lung perfusion (EVLP) systems, and more recently the acceptance of hepatitis C donors have started to close the gap between organ donors and recipients in need of lung transplantation. This article focuses on the expansion of donor lungs for transplantation after DCD, the use of EVLP in evaluating extended criteria lungs, and the use of lung grafts from donors with hepatitis C."

Lung Transplantation From Controlled and Uncontrolled Donation After Circulatory Death (DCD) Donors With Long Ischemic Times Managed by Simple Normothermic Ventilation and Ex-Vivo Lung Perfusion Assessment

Donation after cardiac death (DCD) donors are still subject of studies. In this prospective cohort trial, we compared outcomes after lung transplantation (LT) of subjects receiving lungs from DCD donors with those of subjects receiving lungs from donation after brain death (DBD) donors (ClinicalTrial.gov: NCT02061462). Lungs from DCD donors were preserved in-vivo through normothermic ventilation, as per our protocol. We enrolled candidates for bilateral LT ≥14 years. Candidates for multi-organ or re-LT, donors aged ≥65 years, DCD category I or IV donors were excluded. We recorded clinical data on donors and recipients. Primary endpoint was 30-day mortality. Secondary endpoints were: duration of mechanical ventilation (MV), intensive care unit (ICU) length of stay, severe primary graft dysfunction (PGD3) and chronic lung allograft dysfunction (CLAD). 121 patients (110 DBD Group, 11 DCD Group) were enrolled. 30-day mortality and CLAD prevalence were nil in the DCD Group. DCD Group patients required longer MV (DCD Group: 2 days, DBD Group: 1 day, p = 0.011). ICU length of stay and PGD3 rate were higher in DCD Group but did not significantly differ. LT with DCD grafts procured with our protocols appears safe, despite prolonged ischemia times.

Prioritizing direct heart procurement in organ donors after circulatory death does not jeopardize lung transplant outcomes

Background

Controlled donation after circulatory death (cDCD) has become a standard in liver, kidney, and lung transplantation (LTx). Based on recent innovations in ex vivo heart preservation, heart transplant centers have started to accept cDCD heart allografts. Because the heart has very limited tolerance to warm ischemia, changes to the cDCD organ procurement procedures are needed. These changes entail delayed ventilation and prolonged warm ischemia for the lungs. Whether this negatively impacts lung allograft function is unclear.

Methods

A retrospective analysis of cDCD lungs transplanted between 2012 and February 2022 at the Medical University of Vienna was performed. The heart + lung group consisted of cases in which the heart was procured by a cardiac team for subsequent normothermic ex vivo perfusion. A control group (lung group) was formed by cases where only the lungs were explanted. In heart + lung group cases, the heart procurement team placed cannulas after circulatory death and a hands-off time, collected donor blood for ex vivo perfusion, and performed rapid organ perfusion with Custodiol solution, after which the heart was explanted. Up to this point, the lung procurement team did not interfere. No concurrent lung ventilation or pulmonary artery perfusion was performed. After the cardiac procurement team left the table, ventilation was initiated, and lung perfusion was performed directly through both stumps of the pulmonary arteries using 2 large-bore Foley catheters. This study analyzed procedural explant times, postoperative outcomes, primary graft dysfunction (PGD), duration of mechanical ventilation, length of intensive care unit (ICU) stay, and early survival after LTx.

Results

A total of 56 cDCD lungs were transplanted during the study period. In 7 cases (12.5%), the heart was also procured (heart + lung group); in 49 cases (87.5%), only the lungs were explanted (lung group). Basic donor parameters were comparable in the 2 groups. The median times from circulatory arrest to lung perfusion (24 minutes vs 13.5 minutes; P = .002) and from skin incision to lung perfusion (14 minutes vs 5 minutes; P = .005) were significantly longer for the heart + lung procedures. However, this did not affect post-transplantation PGD grade at 0 hours (P = .851), 24 hours (P = .856), 48 hours (P = .929), and 72 hours (P = .874). At 72 hours after transplantation, none of the lungs in the heart + lung group but 1 lung (2.2%) in lung group was in PGD 3. The median duration of mechanical ventilation (50 hours vs 41 hours; P = .801), length of ICU stay (8 days vs 6 days; P = .951), and total length of hospital stay (27 days vs 25 days; P = .814) were also comparable in the 2 groups. In-hospital mortality occurred in only 1 patient of the lung group (2.2%).

Conclusions

Although prioritized cDCD heart explantation is associated with delayed ventilation and significantly longer warm ischemic time to the lungs, post-LTx outcomes within the first year are unchanged. Prioritizing heart perfusion and explantation in the setting of cDCD procurement can be considered acceptable.

Donation after circulatory death donors in lung transplantation

Transplantation of any organ into a recipient requires a donor. Lung transplant has a long history of an inadequate number of suitable donors to meet demand, leading to deaths on the waiting list annually since national data was collected, and strict listing criteria. Before the Uniform Determination of Death Act (UDDA), passed in 1980, legally defined brain death in the U.S., all donors for lung transplant came from sudden death victims [uncontrolled Donation after Circulatory Death donors (uDCDs)] in the recipient’s hospital emergency department. After passage of the UDDA, uDCDs were abandoned to Donation after Brain Death donors (DBDs)—perhaps prematurely. Compared to livers and kidneys, many DBDs have lungs that are unsuitable for transplant, due to aspiration pneumonia, neurogenic pulmonary edema, trauma, and the effects of brain death on lung function. Another group of donors has become available—patients with a devastating irrecoverable brain injury that do not meet criteria for brain death. If a decision is made by next-of-kin (NOK) to withdraw life support and allow death to occur by asphyxiation, with NOK consent, these individuals can have organs recovered if death occurs relatively quickly after cessation of mechanical ventilation and maintenance of their airway. These are known as controlled Donation after Circulatory Death donors (cDCDs). For a variety of reasons, in the U.S., lungs are recovered from cDCDs at a much lower rate than kidneys and livers. Ex-vivo lung perfusion (EVLP) in the last decade has had a modest impact on increasing the number of lungs for transplant from DBDs, but may have had a larger impact on lungs from cDCDs, and may be indispensable for safe transplantation of lungs from uDCDs. In the next decade, DCDs may have a substantial impact on the number of lung transplants performed in the U.S. and around the world.

Antemortem Heparin in Organ Donation After Circulatory Death Determination: A Systematic Review of the Literature

Donation after circulatory death determination frequently involves antemortem heparin administration to mitigate peri-arrest microvascular thrombosis. We systematically reviewed the literature to: (1) describe heparin administration practices and (2) explore the effects on transplant outcomes. We searched MEDLINE and EMBASE for studies reporting donation after circulatory death determination heparin practices including use, dosage, and timing (objective 1). To explore associations between antemortem heparin and transplant outcomes (objective 2), we (1) summarized within-study comparisons and (2) used meta-regression analyses to examine associations between proportions of donors that received heparin and transplant outcomes. We assessed risk of bias using the Newcastle Ottawa Scale and applied the GRADE methodology to determine certainty in the evidence. For objective 1, among 55 eligible studies, 48 reported heparin administration to at least some donors (range: 15.8%-100%) at variable doses (up to 1000 units/kg) and times relative to withdrawal of life-sustaining therapy. For objective 2, 7 studies that directly compared liver transplants with and without antemortem heparin reported lower rates of primary nonfunction, hepatic artery thrombosis, graft failure at 5 y, or recipient mortality (low certainty of evidence). In contrast, meta-regression analysis of 32 liver transplant studies detected no associations between the proportion of donors that received heparin and rates of early allograft dysfunction, primary nonfunction, hepatic artery thrombosis, biliary ischemia, graft failure, retransplantation, or patient survival (very low certainty of evidence). In conclusion, antemortem heparin practices vary substantially with an uncertain effect on transplant outcomes. Given the controversies surrounding antemortem heparin, clinical trials may be warranted.

Lung transplantation from uncontrolled and controlled donation after circulatory death: similar outcomes to brain death donors

Controlled donation after circulatory death donors (cDCD) are becoming a frequent source of lungs grafts worldwide. Conversely, lung transplantations (LTx) from uncontrolled donors (uDCD) are sporadically reported. We aimed to review our institutional experience using both uDCD and cDCD and compare to LTx from brain death donors (DBD). This is a retrospective analysis of all LTx performed between January 2013 and December 2019 in our institution. Donor and recipient characteristics were collected and univariate, multivariate and survival analyses were carried out comparing the three cohorts of donors. A total of 239 (84.7%) LTx were performed from DBD, 29 (10.3%) from cDCD and 14 (5%) from uDCD. There were no statistically significant differences in primary graft dysfunction grade 3 at 72 h, 30- and 90-day mortality, need for extracorporeal membrane oxygenation after procedure, ICU and hospital length of stay, airway complications, CLAD incidence or survival at 1 and 3 years after transplant (DBD: 87.1% and 78.1%; cDCD: 89.7% and 89.7%; uDCD: 85.7% and 85.7% respectively; P = 0.42). Short- and mid-term outcomes are comparable between the three types of donors. These findings may encourage and reinforce all types of donation after circulatory death programmes as a valid and growing source of suitable organs for transplantation.

Current status and further potential of lung donation after circulatory death

Chronic organ shortage remains the most limiting factor in lung transplantation. To overcome this shortage, a minority of centers have started with efforts to reintroduce donation after circulatory death (DCD). This review aims to evaluate the experimental background, the current international clinical experience, and the further potential and challenges of the different DCD categories. Successful strategies have been implemented to reduce the problems of warm ischemic time, thrombosis after circulatory arrest, and difficulties in organ assessment, which come with DCD donation. From the currently reported results, controlled-DCD lungs are an effective and safe method with good mid-term and even long-term survival outcomes comparable to donation after brain death (DBD). Primary graft dysfunction and onset of chronic allograft dysfunction seem also comparable. Thus, controlled-DCD lungs should be ceased to be treated as marginal and instead be promoted as an equivalent alternative to DBD. A wide implementation of controlled-DCD-lung donation would significantly decrease the mortality on the waiting list. Therefore, further efforts in establishment of legislation and logistics are crucial. With regard to uncontrolled DCD, more data are needed analyzing long-term outcomes. To help with the detailed assessment and improvement of uncontrolled or otherwise questionable grafts after retrieval, ex-vivo lung perfusion is promising.

Long-Term Outcomes of Cadaveric Lobar Lung Transplantation: An Important Surgical Option

BACKGROUND

Cadaveric lobar lung transplantation (L-LTx) is developed to overcome donor-recipient size mismatch. Controversial short- and long-term outcomes following L-LTx have been reported compared to full-sized lung transplantation (F-LTx). This study reports long-term outcomes after L-LTx.

METHODS

We reviewed patients undergoing lung transplantation (LTx) between 2000 and 2016. The decision to perform L-LTx was made based mainly on donor-recipient height discrepancy and visual assessment of donor lungs. Predicted donor-recipient total lung capacity (TLC) ratio was calculated more recently. Primary outcome was overall survival.

RESULTS

In all, 370 bilateral LTx were performed during the study period, among those 250 (67%) underwent F-LTx and 120 (32%) underwent L-LTx, respectively. One- and 5-year survival rates were 85% vs. 90% and 53% vs. 63% for L-LTx and F-LTx, respectively (p = 0.16). Chronic lung allograft dysfunction (CLAD)-free survival at 5 years was 48% in L-LTx vs. 51% in F-LTx recipients (p = 0.89), respectively. Age, intraoperative extracorporeal membrane oxygenation (ECMO) use, intensive care unit (ICU) stay, and postoperative renal replacement therapy (RRT) were significant prognostic factors for survival using multivariate analysis.

CONCLUSIONS

Overall survival and CLAD-free survival following L-LTx were comparable to F-LTx. Given the ongoing donor organ shortage, cadaveric L-LTx remains as an important resource in LTx.

Utilization of extracorporeal membrane oxygenation in DCD and DBD lung transplants: a 2-year single-center experience

Donation after circulatory death (DCD) has the potential to expand the lung donor pool. We aimed to assess whether DCD affected the need for perioperative extracorporeal membrane oxygenation (ECMO) and perioperative outcomes in lung transplantation (LTx) as compared to donation after brain death (DBD). All consecutive LTxs performed between April 2017 and March 2019 at our tertiary center were analyzed. Donor and recipient preoperative characteristics, utilization of ECMO, and perioperative clinical outcomes were compared between DCD and DBD LTx. Multivariate models (frequentist and Bayes) were fitted to evaluate an independent effect of DCD on the intra- and postoperative need for ECMO. Out of 105 enrolled patients, 25 (23.8%) were DCD LTx. Donors' and preoperative recipients' characteristics were comparable between the groups. Intraoperatively, mechanical circulatory support (MCS) was more common in DCD LTx (56.0% vs. 36.2%), but the adjusted difference was minor (RR = 1.16, 95% CI 0.64-2.12; P = 0.613). MCS duration, and first and second lung ischemia time were longer in the DCD group. Postoperatively, DCD recipients more commonly required ECMO (32.0% vs. 7.5%) and the difference remained considerable after adjustment for the pre- and intraoperative covariates: RR = 4.11 (95% CI 0.95-17.7), P = 0.058, Bayes RR = 4.15 (95% CrI 1.28-13.0). Sensitivity analyses (two DCD-DBD matching procedures) supported a higher risk of postoperative ECMO need in DCD patients. Incidence of delayed chest closure, postoperative chest drainage, and renal replacement therapy was higher in the DCD group. Early postoperative outcomes after DCD LTx appeared generally comparable to those after DBD LTx. DCD was associated with a higher need for postoperative ECMO which could influence clinical outcomes. However, as the DCD group had a significantly higher use of EVLP with more common ECMO preoperatively, this might have contributed to worse outcomes in the DCD group.

Lung transplantation from donation after controlled cardiocirculatory death. Systematic review and meta-analysis

BACKGROUND

The interest in donation after cardiocirculatory death (DCD) donors for lung transplantation (LT) has been recently rekindled due to lung allograft shortage. Clinical outcomes following DCD have proved satisfactory. The aim of this systematic review is to provide a thorough analysis of published experience regarding outcomes of LT after controlled DCD compared with donation after brain death (DBD) donors.

METHODS

We performed a literature search in Cochrane Database of Systematic Reviews, PubMed and Web of Science using the items "lung transplantation" AND "donation after circulatory death" on November 1, 2018. The full text of relevant articles was evaluated by two authors independently. Quality assessment was performed using the NIH protocol for case-control and case series studies. A pooled Odds ratio (OR) and mean differences with inverse variance weighting using DerSimonian-Laird random effect models were computed to account for between-trial variance (τ2).

RESULTS

Of the 508 articles identified with our search, 9 regarding controlled donation after cardiac death (cDCD) were included in the systematic review, including 2973 patients (403 who received graft from DCD and 2570 who had DBD). Both 1-year survival and 2 and 3-grade primary graft dysfunction (PGD) were balanced between the two cohorts (OR = 1.00 and 1.03 respectively); OR for airway complications was 2.07 against cDCD. We also report an OR = 0.57 for chronic lung allograft dysfunction (CLAD) and an OR = 0.57 for 5-year survival against cDCD.

CONCLUSIONS

Our meta-analysis shows no significant difference between recipients after cDCD or DBD regarding 1-year survival, PGD and 1-year freedom from CLAD. Airway complications and long-term survival were both related with transplantation after cDCD, but these statistical associations need further research.

Mitigation of Primary Graft Dysfunction in Lung Transplantation: Current Understanding and Hopes for the Future

Primary graft dysfunction (PGD) is a form of acute lung injury that develops within the first 72 hours after lung transplantation. The overall incidence of PGD is estimated to be around 30%, and the 30-day mortality for grade 3 PGD around 36%. PGD is also associated with the development of bronchiolitis obliterans syndrome, a specific form of chronic lung allograft dysfunction. In this article, we will discuss perioperative strategies for PGD prevention as well as possible future avenues for prevention and treatment.

Whole-brain death and integration: realigning the ontological concept with clinical diagnostic tests

For decades, physicians, philosophers, theologians, lawyers, and the public considered brain death a settled issue. However, a series of recent cases in which individuals were declared brain dead yet physiologically maintained for prolonged periods of time has challenged the status quo. This signals a need for deeper reflection and reexamination of the underlying philosophical, scientific, and clinical issues at stake in defining death. In this paper, I consider four levels of philosophical inquiry regarding death: the ontological basis, actual states of affairs, epistemological standards, and clinical criteria for brain death. I outline several candidates for the states of affairs that may constitute death, arguing that we should strive for a single, unified ontological definition of death as a loss of integrated functioning as a unified organism, while acknowledging that two states of affairs (cardiopulmonary death and whole-brain death) may satisfy this concept. I argue that the clinical criteria for determining whole-brain death should be bolstered to meet the epistemic demand of sufficient certainty in defining death by adding indicators of cerebro-somatic dis-integration to the traditional triad of loss of consciousness, loss of brainstem function, and absence of confounding explanations.