Objective Normothermic ex vivo lung perfusion is a novel method to evaluate and improve the function of injured donor lungs. We reviewed our experience with 50 consecutive transplants after ex vivo ...lung perfusion. Methods A retrospective study using prospectively collected data was performed. High-risk brain death donor lungs (defined as Pa o2 /F io2 <300 mm Hg or lungs with radiographic or clinical findings of pulmonary edema) and lungs from cardiac death donors were subjected to 4 to 6 hours of ex vivo lung perfusion. Lungs that achieved stable airway and vascular pressures and Pa o2 /F io2 greater than 400 mm Hg during ex vivo lung perfusion were transplanted. The primary end point was the incidence of primary graft dysfunction grade 3 at 72 hours after transplantation. End points were compared with lung transplants not treated with ex vivo lung perfusion (controls). Results A total of 317 lung transplants were performed during the study period (39 months). Fifty-eight ex vivo lung perfusion procedures were performed, resulting in 50 transplants (86% use). Of these, 22 were from cardiac death donors and 28 were from brain death donors. The mean donor Pa o2 /F io2 was 334 mm Hg in the ex vivo lung perfusion group and 452 mm Hg in the control group ( P = .0001). The incidence of primary graft dysfunction grade 3 at 72 hours was 2% in the ex vivo lung perfusion group and 8.5% in the control group ( P = .14). One patient (2%) in the ex vivo lung perfusion group and 7 patients (2.7%) in the control group required extracorporeal lung support for primary graft dysfunction ( P = 1.00). The median time to extubation, intensive care unit stay, and hospital length of stay were 2, 4, and 20 days, respectively, in the ex vivo lung perfusion group and 2, 4, and 23 days, respectively, in the control group ( P > .05). Thirty-day mortality (4% in the ex vivo lung perfusion group and 3.5% in the control group, P = 1.00) and 1-year survival (87% in the ex vivo lung perfusion group and 86% in the control group, P = 1.00) were similar in both groups. Conclusions Transplantation of high-risk donor lungs after 4 to 6 hours of ex vivo lung perfusion is safe, and outcomes are similar to those of conventional transplants. Ex vivo lung perfusion improved our center use of donor lungs, accounting for 20% of our current lung transplant activity.
Availability of organs is a limiting factor for lung transplantation, leading to substantial mortality rates on the wait list. Use of organs from donors with transmissible viral infections, such as ...hepatitis C virus (HCV), would increase organ donation, but these organs are generally not offered for transplantation due to a high risk of transmission. Here, we develop a method for treatment of HCV-infected human donor lungs that prevents HCV transmission. Physical viral clearance in combination with germicidal light-based therapies during normothermic ex-vivo Lung Perfusion (EVLP), a method for assessment and treatment of injured donor lungs, inactivates HCV virus in a short period of time. Such treatment is shown to be safe using a large animal EVLP-to-lung transplantation model. This strategy of treating viral infection in a donor organ during preservation could significantly increase the availability of organs for transplantation and encourages further clinical development.
Increasing evidence indicates that regulated necrosis plays a critical role during cell death caused by ischemia-reperfusion (IR) injury. Necroptosis is one form of regulated necrosis. Necrostatin-1 ...(Nec-1), an inhibitor of receptor-interacting protein kinase 1 (RIPK1), is known to reduce necroptosis. We investigated the effect of Nec-1 treatment on IR-induced lung injury in a rat lung transplant model.
Lewis rats were divided into 4 groups (n = 6 each): (1) Control (no treatment), (2) Donor treatment (D), (3) Recipient treatment (R), and (4) Donor plus Recipient treatment (D+R) groups. Donor lungs were flushed and preserved for 18 hours at 4ºC before transplantation. Recipient animals underwent a left single lung transplant. After 2 hours of reperfusion, we assessed the physiologic function, cytokine expression, pathway activation, and the extent of necrosis.
Pulmonary gas exchange in D+R group was significantly better than in the other 3 groups (p = 0.003). Lung edema was significantly lower in the D+R group compared with the Control group (p = 0.006). The expression of interleukin-6 in lung tissue and plasma was significantly reduced in the D+R group compared with the Control group (p = 0.036). The percentage of necrotic cells in D+R group was significantly lower than in the Control and D groups (p = 0.01), indicating Nec-1inhibited regulated necrosis.
The administration of Nec-1 to both donor and recipient improved graft function after lung transplantation through the reduction of necroptosis. The inhibition of regulated necrosis appears to be a promising strategy to attenuate IR lung injury after lung transplantation.
Ex vivo lung perfusion (EVLP) is being increasingly applied as a method to evaluate and treat donor lungs for transplantation. However, with the previous limited worldwide experience, no studies have ...been able to evaluate the impact of indication for EVLP on organ utilization rates and recipient outcomes after lung transplantation (LTx). We examined these outcomes in a large-cohort, single-center series of clinical EVLP cases.
All EVLP procedures performed at our institution between October 2008 and December 2017 were examined. The EVLPs were divided into 4 groups based on the indication for the procedure: group 1, high-risk brain death donors (HR-BDD); group 2, standard-risk donation after cardiac death (S-DCD); group 3, high-risk donation after cardiac death (HR-DCD); and group 4, logistics (LOGISTICS, the need for prolongation of preservation time or organ retrieval by a different transplantation team).
During the study period, a total of 1106 lung transplants were performed in our institution. In this period, 372 EVLPs were performed, 255 (69%) of which were accepted for transplantation, resulting in 262 transplants. Utilization rates were 70% (140 of 198) for group 1, 82% (40 of 49) for group 2, 63% (69 of 109) for group 3, and 81% (13 of 16) for group 4 (P = .42, Fisher's exact test). Recipient age (P = .27) and medical diagnosis (P = .31) were not different across the 4 groups. Kaplan–Meier survival by EVLP indication group demonstrated no differences. Thirty-day mortality was 2.1% in group 1, 5% in group 2, 2.9% in group 3, and 0% in group 4 (P = .87, Fisher's exact test). The median days of mechanical ventilation, intensive care unit stay, and hospital stay were 2, 4, and 21 in group 1; 2, 3, and 21 in group 2; 3, 5, and 28 in group 3; and 2, 4, and 17 in group 4 (P = .29, .17, and .09, respectively, Kruskal–Wallis rank-sum test).
Clinical implementation of EVLP has allowed our program to expand the annual lung transplantation activity by 70% in this time period. It has improved confidence in the utilization of DCD lungs and BDD lungs, with an average 70% utilization of post-EVLP treated donor lungs with excellent outcomes, while addressing significant challenges in donor lung assessment and the logistics of “real-life” clinical lung transplantation.
Strategies to prolong homeostasis of ex vivo perfused lungs Takahashi, Mamoru; Andrew Cheung, Hei Yu; Watanabe, Tatsuaki ...
The Journal of thoracic and cardiovascular surgery,
June 2021, 2021-Jun, 2021-06-00, 20210601, Letnik:
161, Številka:
6
Journal Article
Recenzirano
Odprti dostop
Ex vivo lung perfusion provides an innovative method to assess and repair donor lungs. The current Toronto ex vivo lung perfusion protocol can reliably and reproducibly preserve lungs for 12 hours. A ...longer ex vivo lung perfusion preservation time could enable the application of more advanced repair therapies and the rescue of more donor lungs for lung transplant. Our objective was to achieve stable 24-hour normothermic ex vivo lung perfusion.
We systematically examined 3 modifications of ex vivo lung perfusion perfusate administration in a large animal 24-hour ex vivo lung perfusion model. Pig lungs were assigned to 4 groups (n = 5 per group): (1) control; (2) continuous replacement of ex vivo lung perfusion perfusate; (3) modified feed, which used a modified solution to maintain perfusate osmolality by adjusting glucose and sodium levels; and (4) total parenteral nutrition, in which we added parenteral nutrition to the perfusate.
Only 1 lung in the control group completed 24-hour ex vivo lung perfusion. However, 24-hour perfusion was achieved in 4 lungs in the continuous replacement group, 3 lungs in the modified feed group, and 4 lungs in the total parenteral nutrition group. The total parenteral nutrition group achieved significantly longer stable perfusion time compared with control (P = .03). Lung function was significantly improved and inflammatory cytokine production was reduced in the continuous replacement and total parenteral nutrition groups compared with control.
Modifications of ex vivo lung perfusion perfusate toward achieving a stable homeostatic state can extend perfusion time for up to 24 hours. Although these modifications allow for prolonged ex vivo lung perfusion, further research will be required to develop stable lung support beyond 24 hours.
Three modifications of EVLP perfusate administration in a pig 24-hour EVLP model. The TPN group achieved significantly longer stable perfusion time compared with control (P = .03). The dotted lines represent 95% confidence interval. Display omitted
Pressure overload is accompanied by cardiac myocyte apoptosis, hypertrophy, and inflammatory/fibrogenic responses that lead to ventricular remodeling and heart failure. Despite incomplete ...understanding of how this process is regulated, the upregulation of tumor necrosis factor (TNF)-alpha after aortic banding in the myocardium is known. In the present study, we tested our hypothesis that TNF-alpha regulates the cardiac inflammatory response, extracellular matrix homeostasis, and ventricular hypertrophy in response to mechanical overload and contributes to ventricular dysfunction.
C57/BL wild-type mice and TNF-knockout (TNF-/-) mice underwent descending aortic banding or sham operation. Compared with sham-operated mice, wild-type mice with aortic banding showed a significant increase in cardiac TNF-alpha levels, which coincided with myocyte apoptosis, inflammatory response, and cardiac hypertrophy in week 2 and a significant elevation in matrix metalloproteinase-9 activity and impaired cardiac function in weeks 2 and 6. Compared with wild-type mice with aortic banding, TNF-/- mice with aortic banding showed attenuated cardiac apoptosis, hypertrophy, inflammatory response, and reparative fibrosis. These mice also showed reduced cardiac matrix metalloproteinase-9 activity and improved cardiac function.
Findings from the present study have suggested that TNF-alpha contributes to adverse left ventricular remodeling during pressure overload through regulation of cardiac repair and remodeling, leading to ventricular dysfunction.
Ex vivo normothermic lung perfusion (EVLP) is a novel platform and method developed to facilitate functional assessment and implementation of advanced therapies for donor lungs prior to ...transplantation. This study aimed to determine the safety and immunological and functional benefits of ex vivo adenoviral human interleukin-10 (AdhIL-10) gene delivery to prevent the development of primary graft dysfunction in a large animal survival model. Pig donor lungs were retrieved, preserved for 6 h at 4°C, and then randomly assigned to four groups: (1) AdhIL-10 gene therapy: 12 h EVLP + AdhIL-10 intra-bronchial delivery; (2) EVLP-control: 12 h EVLP; (3) Vector-control: 12 h EVLP + adenoviral vector intra-bronchial delivery; and (4) prolonged hypothermic preservation: additional 12 h of cold ischemia. The left lung was then transplanted and evaluated. The recipients were recovered and kept alive until day 7 post-transplant under standard triple immunosuppression. Plasma levels of hIL-10 were detected in the treatment group throughout the 7 days. Analysis of peripheral blood obtained after transplant showed no signs of hematological, renal, or hepatic toxicity in the AdhIL-10 group. The immediate post-transplant lung function was significantly better in the EVLP-control and AdhIL-10 groups. Gas exchange at day 7 was superior in allografts from the AdhIL-10 group, and the histologic inflammation score was significantly lower. Lymphocytes from AdhIL-10 group harvested from mediastinal lymph nodes at day 7 post-transplantation and co-cultured with donor lymphocytes showed significantly less interferon gamma production in an Enzyme-Linked ImmunoSpot assay when compared with non-treatment groups. It has been demonstrated in this preclinical large animal survival study that ex vivo treatment with AdhIL-10 is safe and improves post-transplant lung function over EVLP alone. Improved function and an immunological advantage in both the innate and adaptive immune responses have been demonstrated.
Acceptance of lungs from donation after circulatory determination of death has been generally restricted to donors who have cardiac arrest within 60 minutes after withdrawal of life-sustaining ...therapies. We aimed to determine the effect of the interval between withdrawal of life-sustaining therapies to arrest and recipient outcomes. Second, we aimed to compare outcomes between donation after circulatory determination of death transplants and donation after neurologic determination of death transplants.
A single-center, retrospective review was performed analyzing the clinical outcomes of transplant recipients who received donation after circulatory determination of death lungs and those who received donation after neurologic determination of death lungs. Donation after circulatory determination of death cases were then grouped on the basis of the interval between withdrawal of life-sustaining therapies and asystole: 0 to 19 minutes (rapid), 20 to 59 minutes (intermediate), and more than 60 minutes (long). Recipient outcomes from each of these groups were compared.
A total of 180 cases of donation after circulatory determination of death and 1088 cases of donation after neurologic determination of death were reviewed between 2007 and 2017. There were no significant differences in the 2 groups in terms of age, gender, recipient diagnosis, and type of transplant (bilateral vs single). Ex vivo lung perfusion was used in 118 of 180 (65.6%) donation after circulatory determination of death cases and 149 of 1088 (13.7%) donation after neurologic determination of death cases before transplantation. The median survivals of recipients who received donation after circulatory determination of death lungs versus donation after neurologic determination of death lungs were 8.0 and 6.9 years, respectively. Time between withdrawal of life-sustaining therapies and asystole was available for 148 of 180 donors (82.2%) from the donation after circulatory determination of death group. Mean and median time from withdrawal of life-sustaining therapies to asystole were 28.6 minutes and 16 minutes, respectively. Twenty donors required more than 60 minutes to experience cardiac arrest, with the longest duration being 154 minutes before asystole was recorded. Recipients of donation after circulatory determination of death lungs who had cardiac arrest at 0 to 19 minutes (90 donors), 20 to 59 minutes (38 donors), and more than 60 minutes (20 donors) did not demonstrate any significant differences in terms of short- and long-term survivals, primary graft dysfunction 2 and 3, intensive care unit stay, mechanical ventilation days, or total hospital stay.
Short- and long-term outcomes in recipients who received donation after neurologic determination of death versus donation after circulatory determination of death lungs are similar. Different withdrawals of life-sustaining therapies to arrest intervals were not associated with recipient outcomes. The maximum acceptable duration of this interval has yet to be established.
The evaluation of donor lungs by normothermic ex vivo acellular perfusion has improved the safety of organ utilization. However, this strategy requires a critical re-evaluation of the parameters used ...to assess lungs during ex vivo perfusion compared with those traditionally used to evaluate the donor lung in vivo. Using a porcine model, we studied the physiology of acellular lung perfusion with the aim of improving the accuracy of clinical ex vivo evaluation.
Porcine lungs after 10 hours of brain death and 24 hours of cold ischemia and uninjured control lungs were perfused for 12 hours and then transplanted. PaO2, compliance, airway pressure and pulmonary vascular resistance were measured. Ventilation with 100% nitrogen and addition of red blood cells to the perfusate were used to clarify the physiologic disparities between in vivo blood perfusion and ex vivo acellular perfusion.
During 12 hours of ex vivo perfusion, injured lungs developed edema with decreased compliance and increased airway pressure, but ex vivo PO2 remained stable. After transplantation, injured lungs demonstrated high vascular resistance and poor PaO2. A reduced effect of shunt on ex vivo lung perfusion PO2 was found to be attributable to the linearization of the relationship between oxygen content and PO2, which occurs with acellular perfusate.
Ex vivo PO2 may not be the first indication of lung injury and, taken alone, may be misleading in assessing the ex vivo lung. Thus, evaluation of other physiologic parameters takes on greater importance.
OBJECTIVES:To study the impact of ex vivo lung perfusion (EVLP) on cytokines, chemokines, and growth factors and their correlation with graft performance either during perfusion or after ...transplantation.
BACKGROUND:EVLP is a modern technique that preserves lungs on normothermia in a metabolically active state. The identification of biomarkers during clinical EVLP can contribute to the safe expansion of the donor pool.
METHODS:High-risk brain death donors and donors after cardiac death underwent 4 to 6 hours EVLP. Using a multiplex magnetic bead array assay, we evaluated analytes in perfusate samples collected at 1 hour and 4 hours of EVLP. Donor lungs were divided into 3 groups(I) Controlbilateral transplantation with good early outcome absence of primary graft dysfunction– (PGD) grade 3; (II) PGD3bilateral transplantation with PGD grade 3 anytime within 72 hours; (III) Declinedlungs unsuitable for transplantation after EVLP.
RESULTS:Of 50 cases included in this study, 27 were in Control group, 7 in PGD3, and 16 in Declined. From a total of 51 analytes, 34 were measurable in perfusates. The best marker to differentiate declined lungs from control lungs was stem cell growth factor -β P < 0.001, AUC (area under the curve) = 0.86 at 1 hour. The best markers to differentiate PGD3 cases from controls were interleukin-8 (P < 0.001, AUC = 0.93) and growth-regulated oncogene-α (P = 0.001, AUC = 0.89) at 4 hours of EVLP.
CONCLUSIONS:Perfusate protein expression during EVLP can differentiate lungs with good outcome from lungs PGD3 after transplantation. These perfusate biomarkers can be potentially used for more precise donor lung selection improving the outcomes of transplantation.
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