Development of New Donor-Specific and Human Leukocyte Antigen Antibodies After Transfusion in Adult Lung Transplantation

OBJECTIVES

The development of new human leukocyte antigens (HLAs) and donor-specific antibodies (DSAs) in patients are associated with worse outcomes following lung transplantation. The authors aimed to examine the relationship between blood product transfusion in the first 72 hours after lung transplantation and the development of HLA antibodies, including DSAs.

DESIGN

A retrospective observational study.

SETTING

At a single academic tertiary center.

PARTICIPANTS

Adult lung transplant recipients who underwent transplantation between September 2014 and June 2019.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A total of 380 patients were included in this study, and 87 (23%) developed de novo donor-specific antibodies in the first year after transplantation. Eighty-five patients (22%) developed new HLA antibodies that were not donor-specific, and 208 patients (55%) did not develop new HLA antibodies in the first year after transplantation. Factors associated with increased HLA and DSA development included donor pulmonary infection, non-infectious indication for transplant, increased recipient body mass index, and a preoperative calculated panel reactive antibody value above 0. Multivariate analysis identified platelet transfusion associated with an increased risk of de novo HLA antibody development compared to the negative group (odds ratio [OR; 95% CI] 1.18 [1.02-1.36]; p = 0.025). Cryoprecipitate transfusion was associated with de novo DSA development compared to the negative group (OR [95% CI] 2.21 [1.32-3.69] for 1 v 0 units; p = 0.002).

CONCLUSIONS

Increased perioperative transfusion of platelets and cryoprecipitate are associated with de novo HLA and DSA development, respectively, in lung transplant recipients during the first year after transplantation.

The American Association for Thoracic Surgery (AATS) 2022 Expert Consensus Document: The use of mechanical circulatory support in lung transplantation

OBJECTIVE

The use of mechanical circulatory support (MCS) in lung transplantation has been steadily increasing over the prior decade, with evolving strategies for incorporating support in the preoperative, intraoperative, and postoperative settings. There is significant practice variability in the use of these techniques, however, and relatively limited data to help establish institutional protocols. The objective of the AATS Clinical Practice Standards Committee (CPSC) expert panel was to review the existing literature and establish recommendations about the use of MCS before, during, and after lung transplantation.

METHODS

The AATS CPSC assembled an expert panel of 16 lung transplantation physicians who developed a consensus document of recommendations. The panel was broken into subgroups focused on preoperative, intraoperative, and postoperative support, and each subgroup performed a focused literature review. These subgroups formulated recommendation statements for each subtopic, which were evaluated by the entire group. The statements were then developed via discussion among the panel and refined until consensus was achieved on each statement.

RESULTS

The expert panel achieved consensus on 36 recommendations for how and when to use MCS in lung transplantation. These recommendations included the use of veno-venous extracorporeal membrane oxygenation (ECMO) as a bridging strategy in the preoperative setting, a preference for central veno-arterial ECMO over traditional cardiopulmonary bypass during the transplantation procedure, and the benefit of supporting selected patients with MCS postoperatively.

CONCLUSIONS

Achieving optimal results in lung transplantation requires the use of a wide range of strategies. MCS provides an important mechanism for helping these critically ill patients through the peritransplantation period. Despite the complex nature of the decision making process in the treatment of these patients, the expert panel was able to achieve consensus on 36 recommendations. These recommendations should provide guidance for professionals involved in the care of end-stage lung disease patients considered for transplantation.

Comparison of Forceps, Cryoprobe, and Thoracoscopic Lung Biopsy for the Diagnosis of Interstitial Lung Disease - The CHILL Study

RATIONALE

Transbronchial lung cryobiopsy (TBLC) has emerged as a less invasive method to obtain a tissue diagnosis in patients with interstitial lung disease (ILD). The diagnostic yield of TBLC compared to surgical lung biopsy (SLB) remains uncertain.

OBJECTIVES

The aim of this study was to determine the diagnostic accuracy of forceps transbronchial lung biopsy (TBLB) and TBLC compared to SLB when making the final diagnosis based on multidisciplinary discussion (MDD).

METHODS

Patients enrolled in the study underwent sequential TBLB and TBLC followed immediately by SLB. De-identified cases, with blinding of the biopsy method, were reviewed by a blinded pathologist and then discussed at a multidisciplinary conference.

MAIN RESULTS

Between August 2013 and October 2017, we enrolled 16 patients. The raw agreement between TBLC and SLB for the MDD final diagnosis was 68.75% with a Cohen's kappa of 0.6 (95% CI 0.39, 0.81). Raw agreement and Cohen's kappa of TBLB versus TBLC and TBLB versus SLB for the MDD final diagnosis were much lower (50%, 0.21 [95% CI 0, 0.42] and 18.75%, 0.08 [95% CI -0.03, 0.19], respectively). TBLC was associated with mild bleeding (grade 1 bleeding requiring suction to clear) in 56.2% of patients.

CONCLUSIONS

In patients with ILD who have an uncertain type based on clinical and radiographic data and require tissue sampling to obtain a specific diagnosis, TBLC showed moderate correlation with SLB when making the diagnosis with MDD guidance. TBLB showed poor concordance with both TBLC and SLB MDD diagnoses.

ISHLT consensus document on lung transplantation in patients with connective tissue disease: Part III: Pharmacology, medical and surgical management of post-transplant extrapulmonary conditions statements

Patients with connective tissues disease (CTD) are often on immunomodulatory agents before lung transplantation (LTx). Till now, there's no consensus on the safety of using these agents perioperative and post-transplant. The International Society for Heart and Lung Transplantation-supported consensus document on LTx in patients with CTD addresses the risk and contraindications of perioperative and post-transplant management of the biologic disease-modifying antirheumatic drugs (bDMARD), kinase inhibitor DMARD, and biologic agents used for LTx candidates with underlying CTD, and the recommendations and management of non-gastrointestinal extrapulmonary manifestations, and esophageal disorders by medical and surgical approaches for CTD transplant recipients.

Lung Transplant from ECMO: Current Results and Predictors of Post-transplant Mortality

Purpose of Review

We examined data from the last 5 years describing extracorporeal life support (ECLS) as a bridge to lung transplantation. We assessed predictors of survival to transplantation and post-transplant mortality.

Recent Findings

The number of lung transplants performed worldwide is increasing. This is accompanied by an increase in the type of patients being transplanted, including sicker patients with more advanced disease. Consequently, there is an increase in the need for bridging strategies, with varying success. Several predictors of failure have been identified. Major risk factors include retransplantation, other organ dysfunction, and deconditioning.

Summary

ECLS is a risky strategy but necessary for patients who would otherwise die if not bridged to transplantation. The presence of predictors for failure is not a contraindication for bridging. However, major risk factors should be approached cautiously. Other, more minor risk factors may be considered acceptable. More importantly, the strategy should be individualized for each patient to achieve the best possible outcomes.

The Association of Increased FFP:RBC Transfusion Ratio to Primary Graft Dysfunction in Bleeding Lung Transplantation Patients

OBJECTIVES

Lung transplantation is associated with a significant risk of needed transfusion. Although algorithm-based transfusion strategies that promote a high fresh frozen plasma:red blood cells (FFP:RBC) ratio have reduced overall blood product requirements in other populations, large-volume transfusions have been linked to primary graft dysfunction (PGD) in lung transplantation, particularly use of platelets and plasma. The authors hypothesized that in lung transplant recipients requiring large-volume transfusions, a higher FFP:RBC ratio would be associated with increased PGD severity at 72 hours.

DESIGN

Observational retrospective review.

SETTING

Single tertiary academic center.

PARTICIPANTS

Adult patients undergoing bilateral or single orthotopic lung transplantation and receiving >4 U PRBC in the first 72 hours from February 2014 to March 2019.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Patient demographics, operative characteristics, blood transfusions, and outcomes including PGD scores and length of stay were collected. Eighty-nine patients received >4U PRBC, had available 72-hour PGD data, and were included in the study. These patients were grouped into a high-ratio (>1:2 units of FFP:RBC, N = 38) or low-ratio group (<1:2 units of FFP:RBC, N = 51). Patients in the high-ratio group received more transfusions and factor concentrates and had significantly longer case length. The high-ratio group had a higher rate of severe PGD at 72 hours (60.5% v 23.5%, p = 0.0013) and longer hospital length of stay (40 v 32 days, p = 0.0273).

CONCLUSIONS

In bleeding lung transplantation patients at high risk for PGD, a high FFP:RBC transfusion ratio was associated with worsened 72-hour PGD scores when compared with the low-ratio cohort.

Patient-Reported Chronic Pain Outcomes After Lung Transplantation

Chronic pain after lung transplantation is a significant concern, in particular given the heterogeneity of the patient population and the challenges of achieving adequate pain control amid concerns related to complex immunosuppressant regimens and the possibility of respiratory depression. We undertook a patient-reported outcomes (PRO) survey administered via our electronic health care portal to examine the postoperative incisional pain prevalence in a cohort of lung transplant recipients at a single, high-volume center where bilateral thoracosternotomy is the preferred surgical approach. The Patient Reported Outcomes Measurement Information System (PROMIS) Global Health and Pain Intensity short forms were sent to a total of 173 lung transplant recipients who were more than 2 months postsurgery at the time of the study. A total of 64 patients responded to both PROMIS surveys (response rate 38%). In the cohort of survey respondents, we observed a chronic pain incidence of 58% after lung transplantation (median pain score 1/10) and an overall good quality of life score (median score 4/5); however, only 9.4% reported moderate-severe pain (pain score ≥5/10). Survey nonrespondents had higher rates of pretransplant opioid and psychiatric medication use compared with respondents. In this study, we demonstrated the feasibility of using an electronic PRO survey for assessing postoperative pain outcomes after lung transplantation. However, measuring pain outcomes using this type of tool highlights issues of response rate and potential selection bias. Larger studies are needed to adequately assess the risk and predictors of chronic pain after lung transplantation and its impact on quality of life.

Is There a Role for Surgery in Patients with Neuroendocrine Tumors of the Esophagus? A Contemporary View from the NCDB

BACKGROUND

Esophageal neuroendocrine tumors (eNETs) are exceedingly rare, aggressive and have a poor prognosis. Treatment guidelines are ill-defined and mainly based on evidence from case reports and analogous experiences drawn from similar disease sites.

METHODS

The NCDB was reviewed for histologically confirmed stage I-III, primary eNETs from 2006 to 2014. Patients were grouped into whether or not they underwent primary tumor resection. Univariate, multivariable, and full bipartite propensity score (PS) adjusted Cox regression analyses were used to assess overall and relative survival differences.

RESULTS

A total of 250 patients were identified. Mean age was 65.0 (standard deviation [SD] 11.9) years, and 174 (69.6%) patients were male. Most patients had stage III disease (n = 136, 54.4%), and the most common type of NET was small cell eNET (n = 111, 44.4%). Chemotherapy was used in 186 (74.4%), radiation therapy in 178 (71.2%), and oncological resection was performed in 69 (27.6%) patients. Crude 2-year survival rates were higher in the operated (57.3%) compared with the nonoperated group (35.2%; p < 0.001). The survival benefit held true after multivariable adjustment (hazard ratio [HR] 0.47, 95% confidence interval [CI] 0.32-0.69, p < 0.001). After full bipartite PS adjustment analysis, survival was longer for patients who received a surgical resection compared with those who did not (HR 0.48, 95% CI 0.31-0.75, p = 0.003) with a corresponding 2-year overall survival rate of 63.3% (95% CI 52.0-77.2) versus 38.8% (95% CI 30.9-48.8), respectively.

CONCLUSIONS

Multimodal treatment that includes surgery is associated with better overall survival for eNETs. Additional research is needed to more definitively identify patients who benefit from esophagectomy and to establish an appropriate treatment algorithm.

Donor and recipient age matching in heart transplantation: analysis of the UNOS Registry

The association of donor and recipient age with survival following adult heart transplantation has not been well characterized. The purpose of this study was to examine the impact of the relationship between donor and recipient age on post-transplant survival. We retrospectively reviewed the 2005-2018 UNOS heart transplant database for all adult recipients undergoing first-time isolated heart transplantation. The impact of donor and recipient age on survival was analyzed with Cox proportional hazards modeling using restricted cubic splines. A total of 25 480 heart transplant donor and recipient pairs met inclusion criteria. Unadjusted and adjusted Cox proportional hazards modeling demonstrated a near-linear association between increasing donor age and decreased survival; in addition, older and younger recipient age was associated with decreased survival. After adjustment, there was no significant interaction between donor and recipient age. Older donors decreased survival similarly in both older and younger recipients. Increasing donor age and both younger and older recipient age are independently associated with worsened post-heart transplant survival. The relationship between donor and recipient age does not significantly affect survival following heart transplant.

Portable normothermic ex-vivo lung perfusion, ventilation, and functional assessment with the Organ Care System on donor lung use for transplantation from extended-criteria donors (EXPAND): a single-arm, pivotal trial

BACKGROUND

Donor lung use for transplantation is the lowest among solid organ tranplants because of several complex and multifactorial reasons; one area that could have a substantial role is the limited capabilities of cold ischaemic storage. The aim of the EXPAND trial was to evaluate the efficacy of normothermic portable Organ Care System (OCS) Lung perfusion and ventilation on donor lung use from extended-criteria donors and donors after circulatory death, which are rarely used.

METHODS

In this single-arm, pivotal trial done in eight institutions across the USA, Germany, and Belgium, lungs from extended-criteria donors were included if fulfilling one or more of the following criteria: a ratio of partial pressure of arterial oxygen (PaO₂) to fractional concentration of oxygen inspired air (FiO₂) in the donor lung of 300 mm Hg or less; expected ischaemic time longer than 6 h; donor age 55 years or older; or lungs from donors after circulatory death that were recruited and assessed using OCS Lung. Lungs were transplanted if they showed stability of OCS Lung variables, PaO₂:FiO₂ was more than 300 mm Hg, and they were accepted by the transplanting surgeon. Patients were adult bilateral lung transplant recipients. The primary efficacy endpoint was a composite of patient survival at day 30 post-transplant and absence of The International Society for Heart & Lung Tranplantation primary-graft dysfunction grade 3 (PGD3) within 72 h post-transplantation, with a prespecified objective performance goal of 65%. The primary analysis population was all transplanted recipients. This trial is registered with ClinicalTrials.gov, number NCT01963780, and is now complete.

FINDINGS

Between Jan 23, 2014, and Oct 23, 2016, 93 lung pairs were perfused, ventilated, and assessed on the OCS Lung. 12 lungs did not meet OCS transplantation criteria so 81 lungs were suitable for transplantation. Two lungs were excluded for logistical reasons, hence 79 (87%) of eligible lungs were transplanted. The primary endpoint was achieved in 43 (54%) of 79 patients and did not meet the objective performance goal. 35 (44%) of 79 patients had PGD3 within the initial 72 h. 78 (99%) of 79 patients had survived at 30 days post-transplant. The mean number of lung graft-related serious adverse events (respiratory failure and major pulmonary-related infection) was 0·3 events per patient (SD 0·5).

INTERPRETATION

Despite missing the objective primary endpoint, the portable OCS Lung resulted in 87% donor lung use for transplantation with excellent clinical outcomes. Many lungs declined by other transplant centres were successfully transplanted using this new technology, which implies its use has the potential to increase the number of lung transplants performed worldwide. Whether similar outcomes could be obtained if these lungs were preserved on ice is unknown and remains an area for future research.

FUNDING

TransMedics Inc.

Impact of Donor Brain Death Duration on Outcomes After Lung Transplantation

BACKGROUND

Donor brain death duration (BDD) may impact posttransplant graft function and survival in lung transplant.

METHODS

We queried the 2007 to 2018 United Network for Organ Sharing Registry for adult recipients undergoing first-time isolated lung transplant. Cox proportional hazard modeling with splines enabled identification of 3 donor brain death intervals for subsequent analysis: short (<24 hours), reference (24-60 hours), and long (>60 hours). The primary outcome was posttransplant survival.

RESULTS

In total, 19,721 donors and recipients met inclusion criteria. Median time from donor brain death until cross-clamp was 36.6 hours (interquartile range, 19.5). Unadjusted overall survival between cohorts was equivalent (log-rank P = .42); however, longer BDD was associated with improved bronchiolitis obliterans syndrome (BOS)-free survival (log-rank P < .001). On multivariable Cox proportional hazards regression, BDD was not associated with recipient survival (P > .05). Similarly, logistic regression did not identify an independent association between BDD and primary graft dysfunction (P > .05). Increased BDD was, however, associated with a decreased risk of acute rejection (long vs reference; adjusted odds ratio, 0.78; 95% confidence interval, 0.64-0.94) and improved BOS-free survival (long vs reference; adjusted hazard ratio, 0.88; 95% confidence interval, 0.81-0.96).

CONCLUSIONS

Donor BDD is not associated with posttransplant survival or primary graft dysfunction. Long donor BDD, however, is associated with a decreased risk for acute rejection and improved BOS-free survival. Therefore, lung allografts from donors with a prolonged length of time from brain death until explant should not be viewed less favorably by donor selection centers.

National Heart, Lung, and Blood Institute and American Association for Thoracic Surgery Workshop Report: Identifying collaborative clinical research priorities in lung transplantation

This report summarizes the discussion and recommendations from the June 2017 NHLBI-AATS Workshop on Identifying Collaborative Clinical Research Priorities in Lung Transplantation.