Abstract
Objective
Ex vivo lung perfusion (EVLP) has resulted in a significant increase in the use of extended-criteria donor lungs without negatively impacting survival outcomes. However, in-house EVLP is resource-intensive, thereby limiting accessibility. Remote, centralized EVLP (rc-EVLP) has been used with acceptable outcomes in a highly protocolized feasibility study, although has not been assessed in a clinical setting. We characterized outcomes of rc-EVLP in a real-world setting and provide clinical associations related to donor use.
Methods
We performed a dual-center, retrospective analysis of consecutive extended-criteria donor lungs evaluated on rc-EVLP between December 1, 2020, and March 20, 2023. Outcomes included transplantation rate, predictors of use, incidence of primary graft dysfunction grade 3 (PGD3), and 1-year survival. Group comparisons were examined using the Fisher exact test or Mann-Whitney U test.
Results
Eighty-two donors were assessed by rc-EVLP; 65% would've been excluded in the previous feasibility trial. Forty-six lungs (56%) were ultimately transplanted. Vascular permeability, static compliance, and oxygen transfer all were associated with use. PGD3 incidence in rc-EVLP recipients was 17%, whereas 1-year survival was 93%. Donor from circulatory death (DCD) lungs assessed by rc-EVLP had a use of 6 of 19 (33%). Greater preprocurement partial pressure of oxygen, arterial/fraction of inspired oxygen ratio and greater oxygen transfer and static compliance assessed after 2 hours on EVLP were associated with increased DCD use. Although PGD3 incidence with DCD lungs was 33%, there was 100% 1-year recipient survival. Finally, 2-hour EVLP assessments may be sufficient for determining donor quality for all lungs.
Conclusions
Remote, centralized EVLP increases the use of extended-criteria donor lungs in a real-world setting and is associated with excellent outcomes. We provide objective criteria that are associated with the decision to use donor from brain death and DCD lungs assessed by rc-EVLP.
Key Words: remote-centralized EVLP, ex vivo lung perfusion (EVLP), extended-criteria donors, donor use, donors of circulatory death (DCD), lung transplantation
The logistics of remote, centralized EVLP with associated pros and cons of this technology.
Central Message.
Real-world use of remote, centralized EVLP to evaluate extended-criteria donors is associated with acceptable results. We highlight clinical parameters associated with greater lung use.
Perspective.
Remote, centralized EVLP (rc-EVLP)is an alternative, low-resource platform to evaluate extended-criteria DBD and DCD lungs. This dual-center, real-world, retrospective analysis reveals a use rate of 56% with rc-EVLP. This study identifies parameters that associate with lung use, even with assessments as short as 2 hours. Recipient outcomes associated with real-world rc-EVLP are excellent.
Lung transplantation can be a life-saving therapy for patients with advanced lung disease, although limitations in donor lung supply have resulted in a waitlist mortality rate of 18.8%.1 Unfortunately, only 25% of available donor lungs are used, further confounding the supply problem.2 Ex vivo lung perfusion (EVLP) has improved donor lung use by enabling closer monitoring of nonstandard donor lungs in an inflated, perfused, normothermic state; the ability to evaluate gas exchange, vascular permeability, pulmonary vascular resistance, lung weight, and metabolic activity, as well as to perform radiographic and bronchoscopic assessments, has resulted in increased use of extended-criteria donors, faster time to transplants for recipients, and fewer waitlist deaths.3 This is particularly important for lungs from donors after circulatory death (DCD), in whom variable warm ischemic times may negatively impact allograft health.4
Recipients of lungs that underwent EVLP with acellular perfusate at a single transplant center have demonstrated noninferior short- and long-term outcomes.5 However, in-house EVLP requires significant hospital resources, staffing, and expertise, which has limited its widespread use.6 As such, alternative strategies for providing EVLP assessment have been explored. A recent feasibility study demonstrated that EVLP performed at a remote, third-party specialized facility was associated with noninferior recipient outcomes when compared with contemporaneous controls.7 This feasibility study used a strict research protocol that prevented use of EVLP to interrupt cold ischemic time for logistical considerations and excluded recipient candidates with critical care needs.
We sought to characterize outcomes of remote, centralized ex vivo lung perfusion (rc-EVLP) when used for clinically pragmatic purposes. We hypothesized that rc-EVLP when used in a real-world setting would increase the donor use and be associated with noninferior short-term outcomes.
Methods
We performed a dual-center, retrospective analysis of consecutive donor lungs referred for rc-EVLP assessment at Mayo Clinic Jacksonville and Vanderbilt University Medical Center between December 1, 2020, and March 20, 2023. Permission to perform this study was obtained by the institutional review boards at both centers (VUMC #230889 on July 6, 2023, and Mayo Clinic Jacksonville #23-007861 [exempt status] on October 11, 2023). Patients’ informed written consent for publication of study data was waived. We sought to identify the use rate for lung transplantation of extended-criteria donors evaluated by rc-EVLP. We also sought to describe clinical characteristics that are associated with organ use, including physiologic parameters assessed on EVLP. Finally, we describe the incidence of severe primary graft dysfunction and 1-year survival associated with rc-EVLP in our cohort.
Donor Allocation and Referral Criteria for Remote, Centralized EVLP
All donor lungs were accepted by each institution in accordance with the standard Organ Procurement and Transplant Network allocation policy. Donor lungs were referred for rc-EVLP by the transplant teams on the basis of previously described criteria.7 Personnel at transplant centers were responsible for assessing lung quality and determining the need for EVLP. In general, lungs were considered for rc-EVLP if they did not meet standard criteria, required additional evaluation time, or would not be used for transplantation without EVLP. Such scenarios included DCD donor, a partial pressure of oxygen, arterial/fraction of inspired oxygen (Pao2/Fio2) ratio <300 mm Hg, pulmonary edema, expected cold ischemic time exceeding 6 hours, donor age greater than 55 years, donor receipt of more than 10 units of blood products, and abnormal imaging or bronchoscopic findings. EVLP was not indicated if it was unlikely to increase the likelihood of organ use; some exclusion criteria used by the participating transplant centers included confirmed pneumonia, persistent purulent secretions, significant lung trauma, and/or lungs from HIV donors.
rc-EVLP
Donor lungs were transported from the donor center after procurement to 1 of 2 third-party facilities located in either Silver Spring, Maryland, or Jacksonville, Florida (Lung Bioengineering, Inc). rc-EVLP was performed by trained EVLP specialists according to the XPS instruction for use by manual (https://www.xvivogroup.com/wp-content/uploads/2024/02/xps_ifu_1-9-9182-0189-revision-s.pdf). The prescribing physician could request changes on the EVLP protocol on the basis of their expertise and condition of the graft(s). Lungs were evaluated on rc-EVLP for up to 5 hours, although shorter periods were accepted. Parameters assessed were oxygen transfer, lung compliance, airway pressure, left atrial pressure, pulmonary artery pressure, glucose use, lactate production, perfusate loss, and lung radiograph. All organs underwent at least 1 bronchoscopic examination. Consultation with Toronto General Hospital lung transplant surgeons was available.
Statistical Analysis
Continuous variables are described as median with interquartile range (IQR) and categorical variables as frequency with percentages. Between-group comparisons differences were examined using the Fisher exact test or Mann-Whitney U test, as appropriate. Statistical analysis was performed using StataBE, version 17 (StataCorp LLC).
Results
A total of 82 donor lungs were referred for rc-EVLP assessment during the study period, of which 47 (57%) were for lung transplant candidates at Mayo Clinic Jacksonville, and the remaining 35 (43%) were for patients at Vanderbilt. The indication for rc-EVLP was for further assessment of extended-criteria organs for 65 (79%) of the donors, whereas the remainder were referred to interrupt the cold ischemic time to facilitate logistics associated with organ transport and/or transplant center workflow. Baseline characteristics of donor lungs referred for rc-EVLP assessment are listed in Table 1.
Table 1.
Baseline donor characteristics
| Characteristic | Total cohort (n = 82) |
Lungs accepted Post-EVLP (n = 46) |
Lungs rejected Post-EVLP (n = 36) |
P value |
|---|---|---|---|---|
| Transplant center | .36 | |||
| Mayo Clinic Jacksonville | 47 (57%) | 24 (52%) | 23 (63%) | |
| Vanderbilt | 35 (43%) | 22 (48%) | 13 (36%) | |
| EVLP indication | .02 | |||
| Abnormal imaging | 26 (32%) | 13 | 13 | |
| Declining gas exchange | 20 (24%) | 12 | 8 | |
| Lung declined in OR | 5 (6%) | 3 | 2 | |
| Abnormal findings intraoperatively | 2 (2%) | 0 | 2 | |
| DCD donor with unclear trajectory | 4 (5%) | 2 | 2 | |
| DCD-NRP lung | 4 (5%) | 0 | 4 | |
| External party procuring; need for further evaluation | 4 (5%) | 2 | 2 | |
| Logistics | 17 (21%) | 14 (30%) | 3 (8%) | |
| Bilateral lungs | 78 (95%) | 43 (93%) | 35 (97%) | .81 |
| Donor age | 32.5 (25-44) | 36 (26-45) | 29 (23-43.5) | .13 |
| Donor female sex | 36 (44%) | 22 (48%) | 14 (39%) | .50 |
| Donor smoker (>20 py) | 9 (12%) | 7 (16%) | 2 (6%) | .29 |
| Donor circulatory death | 19 (23%) | 6 (13%) | 13 (36%) | .02 |
| Last Pao2/Fio2 | 431 (379-488) | 433 (388-506) | 425 (355-487) | .35 |
| Cold ischemic time 1 | 318 (232-400) | 328 (263-402) | 296 (220-376) | .14 |
| Sequence number | 10.5 (3-51) | 11 (4-45) | 10 (3-55) | .67 |
| EVLP | ||||
| PVR 2 h | 130 (87-182) | 131 (86-190) | 125 (87-178) | .97 |
| PVR 3 h | 130 (88-201) | 141 (89-213) | 121 (88-182) | .41 |
| Perfusate loss 2 h, mL | 105 (79-151) | 132 (89-168) | 85 (57-106) | <.01 |
| Perfusate loss 3 h, mL | 103 (75-148) | 117 (87-184) | 78 (54-114) | <.01 |
| Static compliance 2 h | 105 (79-151) | 132 (89-168) | 85 (57-106) | <.01 |
| Static compliance 3 h | 103 (75-148) | 117 (87-184) | 78 (54-114) | <.01 |
| Left atrium glucose, 2 h | 7.8 (6.8-8.6) | 7.9 (7.5-8.6) | 7.1 (5.9-8.2) | .01 |
| Left atrium glucose 3 h | 5.9 (5-7.3) | 6.0 (5.1-7.1) | 5.9 (4.9-7.4) | .61 |
| Left atrium lactate 2 h | 5.6 (4.0-6.9) | 5.4 (4.0-6.3) | 6.0 (4.3-8.2) | .11 |
| Left atrium lactate 3 h | 8.4 (6.3-10.5) | 8.3 (6.7-10.5) | 8.8 (6.0-10.2) | .85 |
| Delta PO2, 2 h | 422 (390-472) | 465 (422-488) | 386 (342-415) | <.01 |
| Delta PO2, 3 h | 429 (372-468) | 452 (421-487) | 370 (348-395) | <.01 |
P values in bold are statistically significant.
EVLP, Ex vivo lung perfusion; OR, operating room; DCD, donor from circulatory death; DCD-NRP, donor from circulatory death; Normothermic regional perfusion; py, pack years; Pao2/Fio2, partial pressure of oxygen, arterial/fraction of inspired oxygen; PVR, pulmonary vascular resistance; delta PO2, oxygen transfer.
Overall, 46 (56%) donor lungs were accepted for implantation after rc-EVLP. Lungs were more likely to be used if the indication for EVLP was interruption of cold ischemic time versus further assessment of extended-criteria donor lungs (14/17 [82%] vs 32/65 [49%], P = .02). Lungs were also more likely to be used from brain dead donors rather from DCD (40/63 [63%] vs 6/19 [32%], P = .02). Donor age, sex, smoking history, gas exchange before procurement, cold ischemic time before EVLP, and sequence number were not predictive of lung acceptance and use.
Donor lungs were assessed on rc-EVLP for a median of 220 minutes (IQR, 209-240 minutes). There were several physiologic parameters obtained on EVLP that were associated with acceptance and use of donor lungs (Figure 1). Decreased perfusate loss (as a measure of vascular permeability) at both 1 and 3 hours was associated with a decision to accept (128 mL [IQR, 100-180] vs 205 mL [IQR 145-293] at 1 hour and 60 mL [IQR, 50-100] vs 130 mL [IQR, 75-215] at 3 hours, both P < .01). Greater static compliance was also associated with a decision to use donor lungs (103 mL/cm H2O [IQR, 76-134 mL/cm H2O] vs 85 mL/cm H2O [IQR, 67-113 mL/cm H2O] at 1 hour, P = .04 and 117 mL/cm H2O [IQR, 87-184 mL/cm H2O] vs 78 mL/cm H2O [IQR, 54-114 mL/cm H2O] at 3 hours, P < .01). Furthermore, greater oxygen transfer (delta PO2) was associated with a greater likelihood for use (440 mm Hg [IQR, 396-497 mm Hg] vs 389 mm Hg [IQR, 327-434 mm Hg] at 1 hour and 452 mm Hg [IQR, 421-487 mm Hg] vs 370 mm Hg [IQR, 348-395 mm Hg] at 3 hours, P < .01). Decreased glucose consumption and lactate production were significantly associated with lung acceptance at 1 hour but not at longer observation periods. Pulmonary vascular resistance did not portend likelihood for lung use at any time point.
Figure 1.
Donor lung physiologic parameters assessed on EVLP associated with transplant use. Shown is a comparison of physiologic assessments at various time points on EVLP between extended-criteria donor lungs that were ultimately accepted for transplantation or declined. A, There were no significant differences in pulmonary vascular resistance between lungs that were accepted or declined within the first 3 hours of rc-EVLP. B, Perfusate loss at 2 hours was 50 mL (IQR, 35-88) in lungs that were accepted versus 100 mL (IQR, 50-130) in declined lungs (P = .05) and 60 mL (IQR, 50-100) versus 130 mL (IQR, 75-215) at 3 hours, P < .01. C, Greater static compliance was also associated with a decision to use donor lungs (132 mL/cm H2O [IQR, 89-168] vs 85 mL/cm H2O [IQR, 57-106] at 2 hours, P < .01 and 117 mL/cm H2O [IQR, 87-184] vs 78 mL/cm H2O [IQR, 54-114] at 3 hours, P < .01). D, Greater oxygen transfer (delta PO2) was associated with a greater likelihood for use (465 mm Hg [IQR, 422-488 mm Hg] vs 386 mm Hg [IQR, 342-415 mm Hg] at 2 hours and 452 mm Hg [IQR, 421-487 mm Hg] vs 370 mm Hg [IQR, 348-395 mm Hg] at 3 hours, P < .01). E, Decreased glucose consumption at 1 and 2 hours on EVLP was significantly associated with lung acceptance but not at longer observation periods (8.2 [7.7-8.8] vs 7.5 [6.6-8.4], P < .01 at 1 hour and 5.4 [4.0-6.25] vs 6.0 [4.3-8.2], P < .01 at 2 hours). F, Decreased lactate production at 1 hour was significantly different between lungs that were accepted or declined but not at other time points (4.1 [3.0-4.9] vs 4.7 [3.3-5.9], P = .03). EVLP, Ex vivo lung perfusion; rc-EVLP, remote, centralized ex vivo lung perfusion; IQR, interquartile range; delta PO2, oxygen transfer.
There were 46 recipients of lungs assessed by rc-EVLP. Median recipient age was 64 years (IQR, 54-68 years). The leading indication for transplantation was interstitial lung disease (34/46, or 74%). The median lung allocation score was 39.82 (IQR, 34.26-45.09). Of the recipients, 6 (13%) required extracorporeal membrane oxygenation as a bridge to transplant before transplant, whereas an additional 8 (17%) were admitted to an intensive care unit before transplant. Two patients received HCV NAT+ donors.
The incidence of primary graft dysfunction grade 3 (PGD3) at 72 hours posttransplant in recipients of lungs that were assessed via rc-EVLP was 8 of 46 (17%). There were no baseline donor or recipient characteristics or EVLP physiologic properties that portended the risk of PGD3 development (Table 2).
Table 2.
Predictors of PGD3 at 72-h posttransplantation
| Characteristic | Whole cohort (N = 46) |
No PGD3 at 72 h (n = 38) |
PGD3 at 72 h (n = 8) |
P value |
|---|---|---|---|---|
| Recipient characteristics | ||||
| Age, y | 64 (54-68) | 64 (54-69) | 59 (53-65) | .37 |
| Underlying disease | .36 | |||
| COPD | 9 (20%) | 9 (24%) | 0 | |
| Pulmonary vascular | 3 (7%) | 2 (5%) | 1 (13%) | |
| Suppurative | 1 (2%) | 1 (3%) | 0 | |
| Interstitial | 33 (72%) | 26 (68%) | 7 (88%) | |
| Lung allocation score | 39.82 (34.26-45.09) | 39.62 (34.26-45.09) | 39.91 (34.12-64.39) | .93 |
| Donor characteristics | ||||
| Donor brain death | 40 (87%) | 33 (87%) | 7 (88%) | 1.00 |
| Age, y | 32.5 (25-44) | 34.5 (25-43) | 39.5 (30.5-52) | .34 |
| Smoking history >20 py | 7 (16%) | 6 (17%) | 1 (13%) | .99 |
| Cold ischemic time 2, min | 255 (221-299) | 252 (197-288) | 279 (230-318) | .30 |
| EVLP parameters | ||||
| Static compliance 3 h | 103 (75-148) | 119 (90-162) | 96 (75-227) | .64 |
| Peak inspiratory pressure 3 h | 1 (12-16) | 13 (12-14) | 12.5 (11-17.5) | .94 |
| Delta PO2 3 h | 429 (372-468) | 455 (429-487) | 443 (394-486) | .63 |
| Perfusate loss 3 h | 75 (50-150) | 60 (50-100) | 55 (35-88) | .38 |
| Lactate 3 h | 8.4 (6.3-10.5) | 8.2 (6.7-10.5) | 9.1 (6.7-10.5) | .68 |
PGD3, Primary graft dysfunction grade 3; COPD, chronic obstructive pulmonary disease; py, pack years; EVLP, ex vivo lung perfusion; delta PO2, oxygen transfer.
Finally, 1-year survival of recipients of EVLP-assessed donor lungs was 93% (n = 43). The etiologies of the premature deaths were COVID-19 pneumonia and respiratory failure, septic shock in the setting of cytomegalovirus viremia, and gastrointestinal bleeding with septic shock in the setting of cytomegalovirus viremia. There were no baseline traits that predicted 1-year mortality (Table 3).
Table 3.
Predictors of 1-year survival
| Characteristic | Whole cohort (N = 46) |
Died 1-y Posttransplant (n = 3) |
Survived 1-y Posttransplant (n = 43) |
P value |
|---|---|---|---|---|
| Recipient characteristics | ||||
| Age, y | 64 (54-68) | 68 (64-70) | 64 (54-68) | .25 |
| Underlying disease | 1.00 | |||
| COPD | 9 (20%) | 0 | 9 (21%) | |
| Pulmonary vascular | 3 (7%) | 0 | 3 (7%) | |
| Suppurative | 1 (2%) | 0 | 1 (2%) | |
| Interstitial | 33 (72%) | 3 (100%) | 30 (70%) | |
| Lung allocation score | 39.82 (34.26-45.09) | 47.9 (43.15-82.7) | 39.40 (33.34-44.66) | .07 |
| PGD3 at 72 h | 8 (17%) | 0 | 8 (19%) | 1.00 |
| Donor characteristics | ||||
| Donor brain death | 40 (87%) | 3 (100%) | 37 (86%) | 1.00 |
| Age, y | 32.5 (25-44) | 26 (20-38) | 36 (28-46) | .17 |
| Smoking history >20 py | 7 (16%) | 0 | 7 (17%) | 1.00 |
| Cold ischemic time 2, min | 255 (221-299) | 248 (221-327) | 257 (201-299) | .82 |
| EVLP parameters | ||||
| Compliance static 3 h | 103 (75-148) | 120 (99-138) | 115 (84-188) | .92 |
| Peak inspiratory pressure, 3 h | 12 (11-16) | 13 (12-14) | 16 (13-19) | .79 |
| Delta PO2, 3 h | 429 (372-468) | 429 (372-443) | 458 (421-493) | .14 |
| Perfusate loss, 3 h | 75 (50-150) | 60 (25-70) | 60 (50-100) | .43 |
| Lactate, 3 h | 8.4 (6.3-10.5) | 9.6 (9.5-10.5) | 8.2 (6.7-10.6) | .32 |
COPD, Chronic obstructive pulmonary disease; PGD3, primary graft dysfunction grade 3; py, pack years; EVLP, ex vivo lung perfusion; delta PO2, oxygen transfer.
Further analysis of DCD donors specifically revealed that a greater Pao2/Fio2 ratio immediately before procurement was associated with a greater likelihood of lung use post-EVLP (521 [IQR, 479-552] vs 380 [IQR, 343-432], P < .01). Physiologic traits obtained on EVLP that were associated with the decision to use DCD donor lungs were greater static compliance at 2 hours (132 mL/cmH2O [IQR, 109-158 mL/cmH2O] vs 95 mL/cmH2O [IQR, 68-104 mL/cmH2O], P = .04) and increased oxygen transfer at 2 hours post-EVLP (471 mm Hg [IQR, 429-489 mm Hg] vs 349 mm Hg [IQR, 289-392 mm Hg], P < .01). There was a nonsignificant trend for decreased glucose use at 2 hours (8.6 mg/dL [IQR, 7.9-9.2 mg/dL] vs 7.8 mg/dL [IQR, 5.3-8.1 mg/dL], P = .05) and decreased lactate production at 2 hours (3.8 mg/dL [IQR, 3.2-5.5 mg/dL] vs 6.0 mg/dL [IQR, 4.3-8.2 mg/dL], P = .05) being predictive of acceptance of DCD lungs after rc-EVLP assessment. Incidence of PGD3 at 72 hours posttransplant was 2 of 6 (33%). One-year survival of recipients of DCD lungs was 100%.
Discussion
In this pragmatic, retrospective, dual-center analysis, we identified that rc-EVLP is associated with a use rate of 56%. In addition to enabling further assessment of extended-criteria donor organs, rc-EVLP can promote logistical flexibility by accommodating interruption of cold ischemic times. We demonstrated that certain physiologic assessments obtained on rc-EVLP were associated with the decision to use these lungs for implantation: decreased vascular permeability, increased static compliance, and increased oxygen transfer all were associated with organ use. The incidence of severe PGD in recipients of remote EVLP-assessed donor lungs was 17%, which is similar to non-EVLP populations.8 One-year survival of recipients of remote EVLP donors was also noninferior to non-EVLP donor populations. Moreover, remote EVLP for DCD lungs was associated with a lower use rate. Greater baseline preprocurement Pao2/Fio2 ratios and greater oxygen transfer and static compliance assessed after 2 hours on EVLP were associated with increased use of DCD lungs. Although incidence of severe PGD was greater in the DCD population, there was 100% 1-year survival of these recipients. Finally, we show that assessment periods as short as two hours on EVLP may be sufficient for determining use of donor organs.
EVLP has revolutionized donor organ assessment and procurement but requires considerable expertise and resources, limiting its use. Recent changes to the allocation system in the United States has resulted in increased travel time for procuring teams, placing additional burdens.9 This comes at a time when most lung transplant centers are already understaffed,10 which limits the availability of local in-house EVLP at most transplant centers. rc-EVLP has the potential to increase access to EVLP. This current study builds on the earlier remote Centralized Lung Evaluation System (CLES) feasibility trial in several ways. First, this “real-world” use of remote EVLP included 30 of 46 (65%) accepted donor lungs that would not have been eligible for inclusion in the feasibility study; 14 of 30 (47%) were included to facilitate logistical flexibility, 2 donors were viremic with hepatitis C, and 14 (47%) recipients required admission to the intensive care unit before transplant. Second, results from the remote CLES cohort were compared with a contemporaneous control group; this study is a pragmatic cohort study that assesses outcomes in consecutive donors referred for remote EVLP. Although neither control groups was as rigorous as a randomized controlled trial, the differing trial designs are complementary. Notably, a parallel assignment matched controlled pivotal clinical trial of remote CLES has now completed enrollment with results forthcoming (NCT #03641677). Another benefit of this study is that it identifies objective EVLP physiologic parameters associated with lungs that will be used for transplantation, which can help guide practitioners on which criteria are important to consider when evaluating EVLP donor lungs. Finally, we demonstrate that abridged EVLP evaluation periods, even as short as 2 hours, can provide critical information regarding lung quality, which to our knowledge has not been described before.
There are limitations to this study. The retrospective design increases the potential for bias. The sample size of this study was moderately large. Moreover, although this is a dual-center study, both centers are located in the southeast; practice patterns and outcomes regarding remote EVLP may differ by region, especially for centers on the west coast. Although there was guidance for referral of donor lungs for EVLP assessment, decision-making regarding use post-EVLP was subjective and at the discretion of the implanting surgeon at each center. Despite these limitations, this study has several merits. The pragmatic design provides insight into novel applications for EVLP. This is a rare study in the EVLP space that is not a single-center experience. In addition, this study provides detailed physiologic data at various time points throughout the EVLP course, which can begin to inform readers about which criteria may be helpful for evaluating usability of EVLP donor lungs, including DCD lungs.
We demonstrate that rc-EVLP facilitates assessment of extended-criteria donor lungs while removing the burden from a resource-laden technology on individual centers. Findings from this study provide objective criteria that may inform decision-making surrounding rc-EVLP and future trial design.
Conflict of Interest Statement
J.M. is Medical Director for Lung Bioengineering in Jacksonville, Fla. All other authors reported no conflicts of interest.
The Journal policy requires editors and reviewers to disclose conflicts of interest and to decline handling or reviewing manuscripts for which they may have a conflict of interest. The editors and reviewers of this article have no conflicts of interest.
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