Lungs from donation after circulatory death donors: an alternative source to brain-dead donors? Midterm results at a single institution

Lung Transplantation in Controlled Donation after Circulatory-Determination-of-Death Using Normothermic Abdominal Perfusion

The main limitation to increased rates of lung transplantation (LT) continues to be the availability of suitable donors. At present, the largest source of lung allografts is still donation after the neurologic determination of death (brain-death donors, DBD). However, only 20% of these donors provide acceptable lung allografts for transplantation. One of the proposed strategies to increase the lung donor pool is the use of donors after circulatory-determination-of-death (DCD), which has the potential to significantly alleviate the shortage of transplantable lungs. According to the Maastricht classification, there are five types of DCD donors. The first two categories are uncontrolled DCD donors (uDCD); the other three are controlled DCD donors (cDCD). Clinical experience with uncontrolled DCD donors is scarce and remains limited to small case series. Controlled DCD donation, meanwhile, is the most accepted type of DCD donation for lungs. Although the DCD donor pool has significantly increased, it is still underutilized worldwide. To achieve a high retrieval rate, experience with DCD donation, adequate management of the potential DCD donor at the intensive care unit (ICU), and expertise in combined organ procurement are critical. This review presents a concise update of lung donation after circulatory-determination-of-death and includes a step-by-step protocol of lung procurement using abdominal normothermic regional perfusion.

Postoperative acute kidney injury and renal replacement therapy after DCD lung transplantation

Acute kidney injury (AKI) after lung transplantation (LTx) is a common complication. We aimed to assess whether donation after circulatory death (DCD) is associated with an increased risk of AKI and renal replacement therapy (RRT) in the early postoperative period compared to the donation after brain death (DBD). Retrospective data on a cohort (N = 95) of LTx patients (DCD n = 17, DBD n = 78) characterized by no use of ex-vivo lung perfusion were analyzed for the incidence of AKI within 30 postoperative days and incidence of RRT within 7 and 30 days. After optimal full matching, an imbalance remained between the DCD and DBD patients in respect to intraoperative use of cardiopulmonary bypass (CPB). Therefore, a further subset (n = 77) was defined that excluded CPB patients, and matching was repeated (DCD n = 13 vs. DBD n = 63) resulting in a fair balance on a range of preoperative characteristics and intraoperative use of ECMO. In both matched subsets, DCD was associated with around twice higher risk of AKI and RRT within 7 and 30 postoperative days. In conclusion, data suggest that DCD could be associated with worse early renal outcomes in a subset of LTx patients and justify further studies on the topic in order to refine further renal care pathways perioperatively.

Physiotherapy in Patients on the Organ Donation Pathway: A Survey of Current Practice

BACKGROUND

The purpose of the survey was to identify the current practices of physiotherapists in the management of patients on the organ donation pathway.

METHODS

The author conducted a cross-sectional telephone survey. Participants were 16 physiotherapists working in intensive care units (ICU) in Queensland, who were involved in the care of patients on the organ donation pathway.

RESULTS

In Queensland ICUs, only 57% of hospitals have formal guidelines for physiotherapy management of patients on the organ donation pathway. When comparing the frequency of interventions with organ donation status, 86% of physiotherapists reported increasing the frequency of interventions once a patient was considered for organ donation. Clinical reasoning was reported as the primary factor affecting intervention choice for 67% of physiotherapists, with no difference in frequency, or choice of intervention in patients for donation after circulatory death, compared with donation after brain death. In hospitals with a level I ICU (with infrequent exposure to organ donation), the use of protocols was supported by 100% of participants, whereas in hospitals with a level II and III ICU (and greater exposure), only 31% of participants supported the use of protocols.

CONCLUSIONS

There are wide variations and a lack of formal guidelines for physiotherapy management of patients on the organ donation pathway; however, clinical reasoning appears to be favored above protocolized management in hospitals with level II and level III ICUs.

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.

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.

Prolonged warm ischemia exacerbated acute rejection after lung transplantation from donation after cardiac death in a mouse

OBJECTIVE

In lung transplantation (LTx) from donation after cardiac death (DCD), the donor lungs are inevitably exposed to warm ischemic time (WIT) between the cardiac arrest and the initiation of cold preservation. We conducted this study to examine the effect of prolonged WIT on lung allograft rejection in a murine model of LTx from DCD.

METHODS

Allogeneic BALB/c → B6 LTx from DCD was performed with a WIT of 15 min (WIT15 group, n = 5) or 60 min (WIT60 group, n = 5). Recipients were immunosuppressed by perioperative costimulatory blockade. The lung allografts were analyzed by histology and flow cytometry on day 7 after the LTx.

RESULTS

Histologically, the rejection grade in the WIT60 group was significantly higher than that in the WIT15 group (3.4 ± 0.4 vs. 2.2 ± 0.2, P = 0.0278). Moreover, the intragraft CD8+ to CD4+ T cell ratio in the WIT60 group was significantly higher than that in the WIT15 group (2.3 ± 0.12 vs. 1.2 ± 0.11, P < 0.0001).

CONCLUSIONS

Prolonged WIT could exacerbate the severity of lung allograft rejection after LTx from DCD. Minimization of the WIT could improve the outcomes after LTx from DCD.

What will it take before a bioengineered heart will be implanted in patients?

PURPOSE OF REVIEW

Heart transplantation is the only curative treatment option for end-stage heart failure. However, a shortage of donor organs is a major limitation of this approach. Regenerative medicine targets the goal of increasing the number of available hearts for transplantation. In this review, we highlight the state of the art of building a bioartificial heart. We summarize the components needed, the hurdles, and likely translational steps to make the dream of transplanting a totally functional bioartificial heart a possibility.

RECENT FINDINGS

The therapies being developed in regenerative medicine aim not only to repair, but also to regenerate or replace failing tissues and organs. The engineering of bioartificial hearts utilizing patient-derived cells could theoretically solve the two main complications of heart transplantations: graft rejection and lifelong immunosuppression. Although many hurdles remain, scientists have reached a point in which some of these hurdles have been overcome. Decellularized heart scaffolds have emerged over the past decade as one of the most promising biofabrications. Two possible options for organ scaffolds exist: nontransplantable human hearts and porcine hearts. The use of these scaffolds could lead to the availability of an unlimited number of transplantable organs. The current challenge remains improving processes required for recellularization - including those for cells, bioreactors, and physiologic conditioning. Researchers should focus to solve these hurdles and pave the way toward the dream of in-vivo bioengineered heart maturation.

SUMMARY

Regenerative medicine has emerged as one of the most promising fields of translational research and has the potential to both minimize the need for donor organs and increase their availability. Meeting the challenge of implanting a totally functional bioengineered heart lies in solving multiple issues simultaneously. Dwarfing the technical hurdles, cost is the largest barrier to success. The scientific hurdles mainly involve scaling up and scaling out of laboratory cell processes, building bioreactors, and delivering cells into every needed region of an organ scaffold. Maintaining sterility and quantifying readiness of the nascent organs are also critical for success.

Lung Transplantation with Controlled Donation after Circulatory Death Donors

Purpose: Utilization of donation after circulatory death (DCD) donors has the potential to decrease donor shortage in lung transplantation (LTx). This study reviews the long-term outcome of LTx from DCD donors.

Methods: We included all consecutive DCD (Maastricht Category III) and all donations after brain death (DBD) donor lung transplants at our Center performed between January 2012 and February 2017. Data were analyzed comparing the two groups in regard of survival after LTx as primary outcome.

Results: Median withdrawal to cardiac arrest time was 17 min (interquartile range [IQR]: 11.5–20.5). Median cardiac arrest to cold perfusion was 32 min (IQR: 24.5–36.5). Primary graft dysfunction (PGD) grade 3 at T72 occurred in three recipients. Chronic lung allograft dysfunction (CLAD) led to death in two cases. In DCD group, there was no 90-day mortality. In DCD, group 1- and 3-year survival rates were 100% and 80%. In DBD group, 1- and 3-year survival rates were 85% and 69% (p = 0.4).

Conclusions: Our report confirmed the comparable outcome from DCD donors compared with DBD donors. Utility of DCD donors is a safe option to overcome donor shortage.

Use of Lung Allografts From Donation After Cardiac Death Donors: A Single-Center Experience

BACKGROUND

Lung transplantation remains the only treatment for end-stage lung disease. Availability of suitable lungs does not parallel this growing trend. Centers using donation after cardiac death (DCD) donor lungs report comparable outcomes with those from brain-dead donors. Donor assessment protocols and consistent surgical teams have been advocated when considering using the use of DCD donors. We present our experience using lungs from Maastricht category III DCD donors.

METHODS

Starting 2007 to July 2016, 73 DCD donors were assessed, 44 provided suitable lungs that resulted in 46 transplants. A 2012 to October 2016 comparative cohort of 379 brain-dead donors were assessed. Recipient and donor characteristics and primary graft dysfunction (PGD) and survival were monitored.

RESULTS

Seventy-three DCD (40% dry run rate) donors assessed yielded 46 transplants (23 double, 6 right, and 17 left). Comparative cohort of 379 brain-dead donors yielded 237 transplants (112 double, 43 right, and 82 left). One- and 3-year recipient survival was 91% and 78% for recipients of DCD lungs and 91% and 75% for recipients of lungs from brain-dead donors, respectively. PGD 2 and 3 in DCD recipients at 72 hours was 4 of 46 (9%) and 6 of 46 (13%), respectively. Comparatively, brain-dead donor recipient cohort at 72 hours with PGD 2 and 3 was 23 of 237 (10%) and 41 of 237 (17%), respectively.

CONCLUSIONS

Our experience reaffirms the use of lungs from DCD donors as a viable source with favorable outcomes. Recipients from DCD donors showed equivalent PGD rate at 72 hours and survival compared with recipients from brain-dead donors.

A Multicenter Study on Long-Term Outcomes After Lung Transplantation Comparing Donation After Circulatory Death and Donation After Brain Death

The implementation of donation after circulatory death category 3 (DCD3) was one of the attempts to reduce the gap between supply and demand of donor lungs. In the Netherlands, the total number of potential lung donors was greatly increased by the availability of DCD3 lungs in addition to the initial standard use of donation after brain death (DBD) lungs. From the three lung transplant centers in the Netherlands, 130 DCD3 recipients were one-to-one nearest neighbor propensity score matched with 130 DBD recipients. The primary end points were primary graft dysfunction (PGD), posttransplant lung function, freedom from chronic lung allograft dysfunction (CLAD), and overall survival. PGD did not differ between the groups. Posttransplant lung function was comparable after bilateral lung transplantation, but seemed worse after DCD3 single lung transplantation. The incidence of CLAD (p = 0.17) nor the freedom from CLAD (p = 0.36) nor the overall survival (p = 0.40) were significantly different between both groups. The presented multicenter results are derived from a national context where one third of the lung transplantations are performed with DCD3 lungs. We conclude that the long-term outcome after lung transplantation with DCD3 donors is similar to that of DBD donors and that DCD3 donation can substantially enlarge the donor pool.

Donors after cardiocirculatory death and lung transplantation

The number of patients actively awaiting lung transplantation (LTx) is more than the number of suitable donor lungs. The percentage of lung retrieval rate is lower when compared to other solid organs. The use of lungs from donation after cardiocirculatory death (DCD) donors is one of the options to avoid organ shortage in LTx. After extensive experimental research, clinical application of DCD donation is becoming wider. The results from most of the centers show at least equal survival rate compared to donors from brain death. This review paper will summarize experimental background and clinical experience from DCD donors.

Analysis of knowledge of the general population and health professionals on organ donation after cardiac death

Objective

To evaluate the knowledge and acceptance of the public and professionals working in intensive care units regarding organ donation after cardiac death.

Methods

The three hospitals with the most brain death notifications in Curitiba were selected, and two groups of respondents were established for application of the same questionnaire: the general public (i.e., visitors of patients in intensive care units) and health professionals working in the same intensive care unit. The questionnaire contained questions concerning demographics, intention to donate organs and knowledge of current legislation regarding brain death and donation after cardiac death.

Results

In total, 543 questionnaires were collected, including 442 from family members and 101 from health professionals. There was a predominance of women and Catholics in both groups. More females intended to donate. Health professionals performed better in the knowledge comparison. The intention to donate organs was significantly higher in the health professionals group (p = 0.01). There was no significant difference in the intention to donate in terms of education level or income. There was a greater acceptance of donation after uncontrolled cardiac death among Catholics than among evangelicals (p < 0.001).

Conclusion

Most of the general population intended to donate, with greater intentions expressed by females. Education and income did not affect the decision. The type of transplant that used a donation after uncontrolled cardiac death was not well accepted in the study population, indicating the need for more clarification for its use in our setting.

Lung Donation After Controlled Circulatory Determination of Death: A Review of Current Practices and Outcomes

BACKGROUND

Since the first reported series in 1995, transplantation of lungs recovered through donation after circulatory determination of death (DCDD) has steadily increased. In some European and Australian centers, controlled DCDD accounts for 15% to 30% of all transplanted lungs. Several transplant centers have reported early and midterm outcomes similar to those associated with the use of donors after brain death. Despite these encouraging reports, less than 2% of all lung transplants in the United States are performed using donors after circulatory determination of death.

METHODS

An electronic search from January 1990 to January 2014 was performed to identify series reporting lung transplant outcomes using controlled DCDD. Data from these publications were analyzed in terms of donor characteristics, donation after circulatory determination of death protocols, recipients' characteristics, and early and midterm outcomes.

RESULTS

Two hundred twenty-two DCDDs were transplanted into 225 recipients. The rate of primary graft dysfunction grade 3 ranged from 3% to 36%. The need for extracorporeal membrane oxygenation support after transplantation ranged from 0% to 18%. The average intensive care unit stay ranged from 4 to 8.5 days and the average hospital stay ranged from 14 to 35 days. Thirty-day mortality ranged from 0% to 11% and 1-year survival from 88% to 100%.

CONCLUSION

Under clinical protocols developed and strictly applied by several experienced lung transplant programs, lungs from controlled DCDD have produced outcomes very similar to those observed with brain death donors.

Lung Quality and Utilization in Controlled Donation After Circulatory Determination of Death Within the United States

Although controlled donation after circulatory determination of death (cDCDD) could increase the supply of donor lungs within the United States, the yield of lungs from cDCDD donors remains low compared with donation after neurologic determination of death (DNDD). To explore the reason for low lung yield from cDCDD donors, Scientific Registry of Transplant Recipient data were used to assess the impact of donor lung quality on cDCDD lung utilization by fitting a logistic regression model. The relationship between center volume and cDCDD use was assessed, and the distance between center and donor hospital was calculated by cDCDD status. Recipient survival was compared using a multivariable Cox regression model. Lung utilization was 2.1% for cDCDD donors and 21.4% for DNDD donors. Being a cDCDD donor decreased lung donation (adjusted odds ratio 0.101, 95% confidence interval [CI] 0.085-0.120). A minority of centers have performed cDCDD transplant, with higher volume centers generally performing more cDCDD transplants. There was no difference in center-to-donor distance or recipient survival (adjusted hazard ratio 1.03, 95% CI 0.78-1.37) between cDCDD and DNDD transplants. cDCDD lungs are underutilized compared with DNDD lungs after adjusting for lung quality. Increasing transplant center expertise and commitment to cDCDD lung procurement is needed to improve utilization.

Bioengineering Human Myocardium on Native Extracellular Matrix

RATIONALE

More than 25 million individuals have heart failure worldwide, with ≈4000 patients currently awaiting heart transplantation in the United States. Donor organ shortage and allograft rejection remain major limitations with only ≈2500 hearts transplanted each year. As a theoretical alternative to allotransplantation, patient-derived bioartificial myocardium could provide functional support and ultimately impact the treatment of heart failure.

OBJECTIVE

The objective of this study is to translate previous work to human scale and clinically relevant cells for the bioengineering of functional myocardial tissue based on the combination of human cardiac matrix and human induced pluripotent stem cell-derived cardiomyocytes.

METHODS AND RESULTS

To provide a clinically relevant tissue scaffold, we translated perfusion-decellularization to human scale and obtained biocompatible human acellular cardiac scaffolds with preserved extracellular matrix composition, architecture, and perfusable coronary vasculature. We then repopulated this native human cardiac matrix with cardiomyocytes derived from nontransgenic human induced pluripotent stem cells and generated tissues of increasing 3-dimensional complexity. We maintained such cardiac tissue constructs in culture for 120 days to demonstrate definitive sarcomeric structure, cell and matrix deformation, contractile force, and electrical conduction. To show that functional myocardial tissue of human scale can be built on this platform, we then partially recellularized human whole-heart scaffolds with human induced pluripotent stem cell-derived cardiomyocytes. Under biomimetic culture, the seeded constructs developed force-generating human myocardial tissue and showed electrical conductivity, left ventricular pressure development, and metabolic function.

CONCLUSIONS

Native cardiac extracellular matrix scaffolds maintain matrix components and structure to support the seeding and engraftment of human induced pluripotent stem cell-derived cardiomyocytes and enable the bioengineering of functional human myocardial-like tissue of multiple complexities.

Expanding the donor pool: donation after cardiac death

Lung transplantation (LTx) is the definitive treatment of patients with end-stage lung disease. Availability of donor lungs remains the primary limitation and leads to substantial wait-list mortality. Efforts to expand the donor pool have included a resurgence of interest in the use of donation after cardiac death (DCD) lungs. Unique in its physiology, lung viability seems more tolerant to the variable durations of ischemia that occur in DCD donors. Initial experience with DCD LTx is promising and, in combination with ex vivo lung perfusion systems, seems a valuable opportunity to expand the lung donor pool.

Lung transplantation with donation after circulatory determination of death donors and the impact of ex vivo lung perfusion

The growing demand for suitable lungs for transplantation drives the quest for alternative strategies to expand the donor pool. The aim of this study is to evaluate the outcomes of lung transplantation (LTx) with donation after circulatory determination of death (DCDD) and the impact of selective ex vivo lung perfusion (EVLP). From 2007 to 2013, 673 LTx were performed, with 62 (9.2%) of them using DCDDs (seven bridged cases). Cases bridged with mechanical ventilation/extracorporeal life support were excluded. From 55 DCDDs, 28 (51%) underwent EVLP. Outcomes for LTx using DCDDs and donation after neurological determination of death (DNDD) donors were similar, with 1 and 5-year survivals of 85% and 54% versus 86% and 62%, respectively (p = 0.43). Although comparison of survival curves between DCDD + EVLP versus DCDD-no EVLP showed no significant difference, DCDD + EVLP cases presented shorter hospital stay (median 18 vs. 23 days, p = 0.047) and a trend toward shorter length of mechanical ventilation (2 vs. 3 days, p = 0.059). DCDDs represent a valuable source of lungs for transplantation, providing similar results to DNDDs. EVLP seems an important technique in the armamentarium to safely increase lung utilization from DCDDs; however, further studies are necessary to better define the role of EVLP in this context.

Long-term results after lung transplantation using organs from circulatory death donors: a propensity score-matched analysis†

OBJECTIVES

Due to organ shortage in lung transplantation (LTx), donation after circulatory death (DCD) has been implemented in several countries, contributing to an increasing number of organs transplanted. We sought to assess long-term outcomes after LTx with organs procured following circulatory death in comparison with those obtained from donors after brain death (DBD).

METHODS

Between January 2007 and November 2013, 302 LTxs were performed in our institution, whereby 60 (19.9%) organs were retrieved from DCD donors. We performed propensity score matching (DCD:DBD = 1:2) based on preoperative donor and recipient factors that were significantly different in univariate analysis.

RESULTS

After propensity matching, there were no statistically significant differences between the groups in terms of demographics and preoperative donor and recipient characteristics. There were no significant differences regarding intraoperative variables and total ischaemic time. Patients from the DCD group had significantly higher incidence of primary graft dysfunction grade 3 at the end of the procedure (P = 0.014), and significantly lower pO2/FiO2 ratio during the first 24 h after the procedure (P = 0.018). There was a trend towards higher incidence of the need for postoperative extracorporeal life support in the DCD group. Other postoperative characteristics were comparable. While the overall cumulative survival was not significantly different, the DCD group had significantly poorer results in terms of bronchiolitis obliterans syndrome (BOS)-free survival in the long-term follow-up.

CONCLUSIONS

Long-term results after LTx with organs procured following DCD are in general comparable with those obtained after DBD LTx. However, patients transplanted using organs from DCD donors have a predisposition for development of BOS in the longer follow-up.

Ex vivo heart perfusion after cardiocirculatory death; a porcine model

BACKGROUND

Donation after cardiocirculatory death (DCD) has lead to an increase in organ availability. However, because of medical, logistic, and ethical issues, the use of hearts from DCD donors for transplantation is not generally considered to be feasible. In this study, we investigated the feasibility of ex vivo resuscitation and assessment of the porcine heart after circulatory death using the organ care system (OCS).

METHODS

Cardiocirculatory death was induced in five pigs by cessation of mechanical ventilation. No heparin was administered. The agonal time (AT) was calculated as the time between a reduction of blood pressure <50 mm Hg or a fall in saturation beneath 70% and the cessation of electrical activity. After a further 15 min of warm ischemia, hearts were procured and implanted into the OCS, mimicking the actual clinical scenario for other organs. Thus, procured grafts were assessed ex vivo over a period of 4 h.

RESULTS

Four hearts were successfully resuscitated on the system (AT 8, 15, 20, and 34 min) Three grafts had excellent visual contractility and lactate trends and were considered to be transplantable. One graft (AT 34 min) had an increased lactate and abnormal contractility being unsuitable for transplantation. One heart with 48-min AT could not be resuscitated.

CONCLUSIONS

Our data show that hearts from nonheparinized DCD porcine donors can be successfully resuscitated using the OCS in a scenario, which closely simulates clinical conditions.

Lung transplantation from donation after cardiocirculatory death: a systematic review and meta-analysis

BACKGROUND

Lung transplantation (LTx) can extend life expectancy and enhance the quality of life for select patients with end-stage lung disease. In the setting of donor lung shortage and waiting list mortality, the interest in donation after cardiocirculatory death (DCD) is increasing. We performed a systematic review and meta-analysis to compare outcomes between DCD and conventional donation after brain death (DBD).

METHODS

PubMed, CINAHL, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Cochrane Central Register of Controlled Trials, Scopus, Web of Science, and ClinicalTrials.gov were searched. We identified original research studies with 1-year post-transplant survival data involving >5 DCD transplants. We performed meta-analyses examining 1-year survival, primary graft dysfunction, and acute rejection after LTx.

RESULTS

We identified 519 citations; 11 observational cohort studies met our inclusion criteria for systematic review, and 6 met our inclusion criteria for meta-analysis. There were no differences found in 1-year mortality after LTx between DCD and DBD cohorts in individual studies or in the meta-analysis (DCD [n = 271] vs DBD [n = 2,369], relative risk [RR] 0.88, 95% confidence interval [CI] 0.59-1.31, p = 0.52, I(2) = 0%). There was also no difference between DCD and DBD in a pooled analysis of 5 studies reporting on primary graft dysfunction (RR 1.09, 95% CI 0.68-1.73, p = 0.7, I(2) = 0%) and 4 studies reporting on acute rejection (RR 0.72, 95% CI 0.49-1.05, p = 0.09, I(2) = 0%).

CONCLUSIONS

Survival after LTx from DCD is comparable to survival after LTx from DBD in observational cohort studies. DCD appears to be a safe and effective method to expand the donor pool.

Lung transplantation from donors after circulatory death using portable ex vivo lung perfusion

BACKGROUND

Donation after circulatory death is a novel method of increasing the number of donor lungs available for transplantation. Using organs from donors after circulatory death has the potential to increase the number of transplants performed.

METHODS

Three bilateral lung transplants from donors after circulatory death were performed over a six-month period. Following organ retrieval, all sets of lungs were placed on a portable ex vivo lung perfusion device for evaluation and preservation.

RESULTS

Lung function remained stable during portable ex vivo perfusion, with improvement in partial pressure of oxygen/fraction of inspired oxygen ratios. Mechanical ventilation was discontinued within 48 h for each recipient and no patient stayed in the intensive care unit longer than eight days. There was no postgraft dysfunction at 72 h in two of the three recipients. Ninety-day mortality for all recipients was 0% and all maintain excellent forced expiratory volume in 1 s and forced vital capacity values post-transplantation.

CONCLUSION

The authors report excellent results with their initial experience using donors after circulatory death after portable ex vivo lung perfusion. It is hoped this will allow for the most efficient use of available donor lungs, leading to more transplants and fewer deaths for potential recipients on wait lists.

Update in lung transplantation 2013

Research in pulmonary transplantation is actively evolving in quality and scope to meet the challenges of a growing population of lung allograft recipients. In 2013, research groups leveraged large publicly available datasets in addition to multicenter research networks and single-center studies to make significant contributions to our knowledge and clinical care in the areas of donor use, clinical transplant outcomes, mechanisms of rejection, infectious complications, and chronic allograft dysfunction.

Intimacy or utility? Organ donation and the choice between palliation and ventilation

Organ donation after brain death provides the most important source for deceased organs for transplantation, both because of the number of potential organ donors that it makes available and also because of the unparalleled viability of the organs retrieved. Analysis of worldwide deceased organ donation rates demonstrates that all countries with high deceased organ donation rates (>20 donors per million population per year) have high brain death rates (>40 brain deaths per million population per year). This analysis makes it clear that countries striving to increase their deceased organ donor rates to world leading levels must increase the rates of donation after brain death. For countries with end-of-life care strategies that stress palliation, advance care planning and treatment withdrawal for the terminally ill, the adoption of initiatives to meaningfully raise deceased donor rates will require increasing the rate at which brain death is diagnosed. This poses a difficult, and perhaps intractable, medical, ethical and sociocultural challenge as the changes that would be required to increase rates of brain death would mean conjugating an intimate clinical and cultural focus on the dying patient with the notion of how this person's death might be best managed to be of benefit to others.

Time to death after withdrawal of treatment in donation after circulatory death (DCD) donors

PURPOSE

Controlled donation after circulatory death (DCD) donors make an important contribution to organ transplantation but there is considerable scope for further increasing the conversion of potential to actual DCD organ donors. The period between withdrawal of life-supporting treatment and death (the withdrawal period) is a major determinant of whether organ donation proceeds and it is therefore timely to review recent relevant studies in this area.

RECENT FINDINGS

The duration and haemodynamic nature of the withdrawal period is extremely variable, and clinical guidelines for management of the potential donor during this period differ widely. Recent evidence suggests that kidneys from DCD donors with a prolonged withdrawal period can be used to increase the number of transplants performed and provide satisfactory graft function, suggesting that it is not the duration but the haemodynamic profile of the donor during this phase that are important. This suggestion questions the relevance of clinical indices predicting death within 1 h of treatment withdrawal.

SUMMARY

Future studies should aim to define clinical and physiological variables during the withdrawal period that can be used to maximize well tolerated use of organs from potential DCD donors; these thresholds are likely to differ according to organ type.