Lung Allocation Score Research Articles

Utilization and outcomes of nonintubated extracorporeal membrane oxygenation as a bridge to lung transplant

BackgroundNon-intubated extracorporeal membrane oxygenation (ECMO) has become an increasingly common method of support for patients with severe respiratory failure. Since data on its use as a bridge to lung transplant remain limited to single-center studies, we evaluated its use in a national cohort. MethodsAdult lung-only transplant recipients bridged with ECMO 5/4/2005-3/8/2023 in the United Network for Organ Sharing database were categorized by use of ECMO and mechanical ventilation at transplant (ECMO+MV vs. ECMO-only). We compared post-transplant intubation and ECMO at 72 hours using logistic regression, length of stay using negative binomial regression, and post-transplant survival using Cox regression. ResultsThe 1,599 transplants identified included 902 (56.4%) bridged with ECMO+MV and 697 (43.6%) bridged with ECMO-only. ECMO-only recipients had higher median age (52 vs. 49 years, p<0.001), shorter ischemic times (5.7 vs. 6.0 hours, p=0.003), and similar lung allocation scores (89.5 vs. 89.6, p=0.11). ECMO-only recipients had lower likelihood of intubation at 72 hours (56.5% vs. 77.5%; aOR 0.33 [95% CI: 0.25, 0.42], p<0.001) and shorter lengths of stay (28 vs. 35 days; coefficient -0.19 [95% CI: -0.27, -0.11], p<0.001). ECMO-only recipients had higher 90-day survival (92.1% vs. 89.1%; aHR 0.69 [95% CI: 0.48, 0.99], p=0.04) but similar 1-year (83.1% vs. 81.5%; aHR 0.87 [95% CI: 0.67, 1.12], p=0.27) and 5-year (54.6% vs. 54.7%; aHR 0.98 [95% CI: 0.82, 1.17], p=0.83) survival. ConclusionsNon-intubated ECMO bridge to lung transplant was associated with improved perioperative outcomes and short-term survival and should be considered for candidates requiring ECMO.

Outcomes of single vs double lung retransplantation in patients with cystic fibrosis

ObjectivePatients requiring lung transplant for cystic fibrosis (CF) may require retransplant due to limited graft survival and otherwise excellent life expectancy. Optimal transplant strategy for this population, including single vs. double lung retransplant, has not been established. MethodsWe performed a retrospective analysis of the UNOS/OPTN database to identify adult lung retransplant recipients from 2005-2021 with a primary diagnosis of CF. Patients were stratified by retransplant type (single lung [re-SLTx] vs. double lung [re-DLTx] retransplant). Descriptive statistics, Kaplan-Meier survival analysis, and multivariable Cox regression were performed. ResultsFrom 2005-2021, 384 recipients underwent retransplant after an initial transplant for an indication of CF; more recipients underwent re-DLTx (N=337 [87.8%]) than re-SLTx (N=47 [12.2%]). The median (IQR) time from initial transplant to retransplant was similar between re-SLTx and re-DLTx recipients (4.4 [2.9-8.6] vs. 4.6 [2.6-7.4] years, p=0.73). Ischemic time was shorter and lung allocation score was lower for re-SLTx than re-DLTx recipients. Median survival after retransplant was significantly shorter for re-SLTx vs. re-DLTx recipients (2.0 [95% CI 1.2-3.5] vs. 4.3 [95% CI 3.5-6.1] years post-retransplant, p=0.008). Median survival for adults with CF undergoing primary transplant for CF in the same period was 9.1 (8.5-9.9) years. After adjusting for donor and recipient characteristics, re-SLTx in patients with CF was associated with 88% higher hazard of mortality than re-DLTx (aHR=1.88 [95% CI 1.28-2.78], p=0.001). ConclusionsIn this analysis of lung retransplant in recipients with CF, re-SLTx was associated with a higher hazard of mortality compared to re-DLTx, supporting re-DLTx as treatment for this population.

Single vs Double Lung Transplantation in Older Adults: A Propensity-Matched Analysis

BackgroundSingle lung transplantation (SLT) is associated with worse long-term outcomes than bilateral lung transplantation (BLT) but is often performed for older adults at risk of not tolerating BLT. Research QuestionHow do the outcomes of SLT and BLT compare among older adult recipients? Study Design and MethodsThe Scientific Registry of Transplant Recipients database (2005-2022) was queried for lung transplant recipients aged ≥65 years. Patients were stratified by whether they underwent BLT or SLT, and propensity matched. Baseline characteristics and morbidity were compared with frequentist statistics. Survival was analyzed via Kaplan-Meier estimation. Risk factors for mortality were identified with Cox regression. ResultsOf 9,904 included patients, 4,829 (48.8%) underwent SLT. SLT patients had lower lung allocation scores (39.6 v. 40.6, p<0.001), more interstitial lung disease (74.4% v. 64.6%, p<0.001) and lower rates of bridging (0.7% v. 2.4%, p<0.001). Groups did not differ significantly by sex, body mass index, or donor characteristics. Propensity matching resulted in 2,539 patients in each group. On matched analysis, SLT patients had shorter lengths of stay (14 v. 18 d), lower reintubation rates (14.7% v. 19.8%), and less postoperative dialysis use (4.2% v. 6.4%) (all p<0.001). SLT patients had comparable survival at 30-days (97.6% v. 97.3%, p=0.414) and 1-year (85.5% v. 86.3%, p=0.496), but lower survival at 5-years (45.4% v. 53.4%, p<0.001) on matched analysis. SLT was a risk factor for 5-year mortality (adjusted hazard ratio: 1.19, p<0.001). InterpretationIn older adults, SLT is associated with less morbidity and comparable early survival relative to BLT, but lower five-year survival. SLT is reasonable to perform in older adults at high risk for BLT.

Outcomes of single-lung retransplantation after double-lung transplantation

ObjectiveTo compare outcomes of single-lung retransplantation (SLRTx) and double-lung retransplantation (DLRTx) after an initial double-lung transplantation. MethodsThe Organ Procurement and Transplantation Network/United Network for Organ Sharing database between May 2005 and December 2022 was retrospectively analyzed. Multiorgan transplantations, repeated retransplantations, and lung retransplantations when the status of the initial transplantation was unknown were excluded. ResultsA total of 891 patients were included in the analysis, included 698 (78.3%) with DLRTx and 193 (21.7%) with SLRTx. The mean lung allocation score was higher in the DLRTx group (59.6 ± 20.7 vs 55.1 ± 19.3; P = .007). The use of extracorporeal membrane oxygenation (ECMO) bridge to lung transplantation was similar in the 2 groups (P = .125), as was waitlist time (P = .610). The need for mechanical ventilation (54.6% vs 35.8%; P = .005) and ECMO (17.9% vs 9.0%; P = .069) at 72 hours post-transplantation was greater in the DLRTx group. However, median post-transplantation hospital stay (21.5 [interquartile range (IQR), 12-35] days versus 20 [IQR, 12-35] days; P = .119) and in-hospital mortality (10.9% [n = 76/698] vs 12.4% [n = 24/193]; P = .547) were comparable in the 2 groups. Long-term survival was significantly better in the DLRTx group (P < .001, log-rank test). In the propensity score–weighted multivariable model, the DLRTx group had 28% lower risk of mortality at any point during follow-up compared to the SLRTx group (hazard ratio, 0.72; 95% confidence interval, 0.57-0.91; P = .006). ConclusionsThe less invasiveness of single-lung transplantation in the retransplantation setting has minimal short-term benefit and is associated with significantly worse long-term survival. Double-lung retransplantation should remain the standard for lung retransplantation after initial double-lung transplantation.

Impact of bridging veno-venous extracorporeal membrane oxygenation to COVID-19 lung transplantation.

Veno-venous extracorporeal membrane oxygenation (VV-ECMO) therapy is being increasingly used as respiratory support for patients with severe coronavirus disease 2019 (COVID-19)-associated acute respiratory distress syndrome (ARDS). However, the long-term outcome of VV-ECMO as a bridge to lung transplantation in COVID-19-associated ARDS remains unclear, hence the purpose of this study aimed to evaluate its long-term outcome, safety, and feasibility. This was a retrospective cohort study from an institutional lung transplantation database between June 2020 and June 2022. Data on demographics, pre-transplantation laboratory values, postoperative outcomes, preoperative and postoperative transthoracic echocardiography findings, and survival rates were collected. Chi-square, Mann-Whitney U, Student's t, Kaplan-Meier, and Wilcoxon signed-rank tests were used for analysis. Twenty-five patients with COVID-19-associated ARDS underwent lung transplant surgery with VV-ECMO bridge. Unfortunately, six patients with COVID-19-associated ARDS using VV-ECMO died while waiting for transplantation during the same study period. Patients with VV-ECMO bridge were a more severe cohort than 16 patients without VV-ECMO bridge (lung allocation score: 88.1 vs. 74.9, P<0.001). These patients had longer intensive care unit and hospital stays (P=0.03 and P=0.02, respectively) and a higher incidence of complications after lung transplantation. The one-year survival rate of patients with VV-ECMO bridge was lower than that of patients without (78.3% vs. 100.0%, P=0.06), but comparable to that of patients with other lung transplant indications (84.2%, P=0.95). Echocardiography showed a decrease in the right ventricular systolic pressure (P=0.01), confirming that lung transplantation improved right heart function. Our findings suggest that VV-ECMO can be used to safely bridge patients with COVID-19 associated ARDS with right heart failure.

The impact of bleeding on outcomes following lung transplantation: a retrospective analysis using the universal definition of perioperative bleeding

BackgroundLung transplantation (LT) represents a high-risk procedure for end-stage lung diseases. This study describes the outcomes of patients undergoing LT that require massive transfusions as defined by the universal definition of perioperative bleeding (UDPB).MethodsAdult patients who underwent bilateral LT at a single academic center were surveyed retrospectively. Patients were grouped by insignificant, mild, or moderate perioperative bleeding (insignificant-to-moderate bleeders) and severe or massive perioperative bleeding (severe-to-massive bleeders) based on the UDPB classification. Outcomes included 1-year survival and primary graft dysfunction (PGD) of grade 3 at 72 h postoperatively. Multivariable models were adjusted for recipient age, sex, body mass index (BMI), Lung allocation score (LAS), preoperative hemoglobin (Hb), preoperative extracorporeal membrane oxygenation (ECMO) status, transplant number, and donor status. An additional multivariable model was created to find preoperative and intraoperative predictors of severe-to-massive bleeding. A p-value less than 0.05 was selected for significance.ResultsA total of 528 patients were included, with 357 insignificant-to-moderate bleeders and 171 severe-to-massive bleeders. Postoperatively, severe-to-massive bleeders had higher rates of PGD grade 3 at 72 h, longer hospital stays, higher mortality rates at 30 days and one year, and were less likely to achieve textbook outcomes for LT. They also required postoperative ECMO, reintubation for over 48 h, tracheostomy, reintervention, and dialysis at higher rates. In the multivariate analysis, severe-to-massive bleeding was significantly associated with adverse outcomes after adjusting for recipient and donor factors, with an odds ratio of 7.73 (95% CI: 4.27–14.4, p < 0.001) for PGD3 at 72 h, 4.30 (95% CI: 2.30–8.12, p < 0.001) for 1-year mortality, and 1.75 (95% CI: 1.52–2.01, p < 0.001) for longer hospital stays. Additionally, severe-to-massive bleeders were less likely to achieve textbook outcomes, with an odds ratio of 0.07 (95% CI: 0.02–0.16, p < 0.001). Preoperative and intraoperative predictors of severe/massive bleeding were identified, with White patients having lower odds compared to Black patients (OR: 041, 95% CI: 0.22–0.80, p = 0.008). Each 1-unit increase in BMI decreased the odds of bleeding (OR: 0.89, 95% CI: 0.83–0.95, p < 0.001), while each 1-unit increase in MPAP increased the odds of bleeding (OR: 1.04, 95% CI: 1.02–1.06, p < 0.001). First-time transplant recipients had lower risk (OR: 0.16, 95% CI: 0.06–0.36, p < 0.001), whereas those with DCD donors had a higher risk of severe-to-massive bleeding (OR: 3.09, 95% CI: 1.63–5.87, p = 0.001).ConclusionThese results suggest that patients at high risk of massive bleeding require higher utilization of hospital resources. Understanding their outcomes is important, as it may inform future decisions to transplant comparable patients.

Induction immunosuppression strategies and outcomes post-lung transplant: A single center experience

PurposeCurrently 80% of lung transplant centers use induction immunosuppression. However, there is a lack of standardization of induction protocols within and across lung transplant centers. This study explores the association of two different induction immunosuppression strategies used at our center [single dose rabbit antithymocyte globulin (rATG) vs. alemtuzumab] compared to no induction with immunologic and clinical outcomes after lung transplantation. MethodsA total of 174 consecutive lung transplant recipients (LTR) between 2016 and 2019 were included in the analysis. Twenty nine LTR (16.7%) received no induction, 22 LTR (12.6%) received alemtuzumab, 123 LTR (70.6%) received a single dose of rATG; 1.5 mg/kg within 24 h of transplant for induction. All LTR had a negative flow cytometry crossmatch on the day of the transplant. All LTR were assessed for de novo HLA donor-specific antibodies (DSA) development and clinical outcomes, including the risk of acute cellular rejection (ACR), antibody-mediated rejection (AMR), chronic lung allograft dysfunction (CLAD), and overall survival post-transplant. ResultsThe median lung allocation score (LAS) was significantly higher in LTR that did not receive Induction immunosuppression (76; range = 35.3–94.3) compared to induction with rATG (41.6; range = 31.6–91) and alemtuzumab (51; range = 33.1–88.2) (p < 0.001). De novo HLA DSA were detected in 50/174 (28.7%) LTR within 12 months post-transplant. They were detected in 13/29 (44.8%) LTR without induction immunosuppression compared to 28/123 (22.8%) and 9/22 (40.9%) LTR with rATG and alemtuzumab induction, respectively (p = 0.02). The percent freedom from ACR rates between LTR who received alemtuzumab induction was significantly higher compared to LTR who received rATG or no induction at 1 (p = 0.02), 2 (p = 0.01) and 3 (p = 0.05) years post-transplant. In addition, the overall 1-year survival rates were significantly higher in LTR who received rATG or alemtuzumab induction compared to LTR without induction immunosuppression (p = 0.02). ConclusionInduction immunosuppression strategies utilizing rATG or Alemtuzumab have unique and contrasting benefits in LTR. Combination of alemtuzumab induction and a lower dose of maintenance immunosuppression may reduce the incidence of ACR in LTR. Single-dose rATG or alemtuzumab induction immunosuppression may also improve the 1 year overall LTR survival compared to no induction.

Impact of Acute Exacerbation of Idiopathic Pulmonary Fibrosis on Lung Transplant Outcomes.

Acute exacerbations of idiopathic pulmonary fibrosis (AE-IPF) are acute, significant respiratory deteriorations in patients with IPF and can lead to increased morbidity and mortality. It remains unclear how AE-IPF impacts lung transplant (LTX) outcomes. All adult patients who were listed for LTX between July 2005 and October 2020 at the Loyola University Medical Center with a diagnosis of IPF were included. Pretransplant characteristics and posttransplant outcomes were gathered via retrospective chart review. The primary outcome was short- and long-term survival for patients transplanted during stable IPF versus those with AE-IPF. One hundred fifty-nine patients were included in this study, 17.6% of whom were transplanted during AE-IPF. AE-IPF patients were more likely to have higher oxygen needs pretransplant, have higher lung allocation score, and were more likely to be intubated or be on extracorporeal membrane oxygenation as compared with stable IPF patients. Survival by AE status at transplant did not differ at 90 d or 1 y posttransplantation. There were also no significant differences in rates of severe primary graft dysfunction or acute rejection within 1 y. Patients with AE-IPF were more likely to have higher oxygenation requirements and higher lung allocation score at the time of LTX than those with stable IPF. Despite this, there were no differences in survival at 90 d, 1 y, or 3 y, or differences in incidence of severe primary graft dysfunction or acute cellular rejection. Transplantation of patients with AE-IPF has clinical outcomes comparable with transplantation of patients with stable IPF. This contrasts with previous studies examining LTX in patients with AE-IPF.

Survival outcomes following urgent lung transplantation in France and the USA

IntroductionLung graft allocation can be based on a score (Lung Allocation Score) as in the USA or sequential proposals combined with a discrete priority model as in France. We aimed...

Implications of Race Adjustment in Lung-Function Equations.

Adjustment for race is discouraged in lung-function testing, but the implications of adopting race-neutral equations have not been comprehensively quantified. We obtained longitudinal data from 369,077 participants in the National Health and Nutrition Examination Survey, U.K. Biobank, the Multi-Ethnic Study of Atherosclerosis, and the Organ Procurement and Transplantation Network. Using these data, we compared the race-based 2012 Global Lung Function Initiative (GLI-2012) equations with race-neutral equations introduced in 2022 (GLI-Global). Evaluated outcomes included national projections of clinical, occupational, and financial reclassifications; individual lung-allocation scores for transplantation priority; and concordance statistics (C statistics) for clinical prediction tasks. Among the 249 million persons in the United States between 6 and 79 years of age who are able to produce high-quality spirometric results, the use of GLI-Global equations may reclassify ventilatory impairment for 12.5 million persons, medical impairment ratings for 8.16 million, occupational eligibility for 2.28 million, grading of chronic obstructive pulmonary disease for 2.05 million, and military disability compensation for 413,000. These potential changes differed according to race; for example, classifications of nonobstructive ventilatory impairment may change dramatically, increasing 141% (95% confidence interval [CI], 113 to 169) among Black persons and decreasing 69% (95% CI, 63 to 74) among White persons. Annual disability payments may increase by more than $1 billion among Black veterans and decrease by $0.5 billion among White veterans. GLI-2012 and GLI-Global equations had similar discriminative accuracy with regard to respiratory symptoms, health care utilization, new-onset disease, death from any cause, death related to respiratory disease, and death among persons on a transplant waiting list, with differences in C statistics ranging from -0.008 to 0.011. The use of race-based and race-neutral equations generated similarly accurate predictions of respiratory outcomes but assigned different disease classifications, occupational eligibility, and disability compensation for millions of persons, with effects diverging according to race. (Funded by the National Heart Lung and Blood Institute and the National Institute of Environmental Health Sciences.).

Body mass index and mortality following primary graft dysfunction: A Lung Transplant Outcomes Group study

Higher body mass index (BMI) increases risk of developing primary graft dysfunction (PGD) after lung transplantation; whether BMI is associated with decreased survival after PGD is unknown. We utilized the Lung Transplant Outcomes Group (LTOG) cohort of 1,538 subjects from 2011-2018. We evaluated the association between pre-operative BMI and graft survival among subjects with severe PGD using Cox proportional hazards models with linear splines. Models were stratified by center and adjusted for sex, age, lung allocation score, and diagnosis. PGD developed in 383 subjects. Among subjects with PGD, low BMI was associated with increased mortality while high BMI was not associated with differential mortality, compared to normal BMI. Results were similar for 90-day and 1-year survival. While high BMI increases risk of developing PGD, it does not appear to be associated with survival after PGD. Future work should focus on PGD prevention rather than PGD management in patients with obesity.

Lung transplantation following prior cardiac surgical procedures

IntroductionAs lung transplant candidates are older with increased comorbidities, we sought to examine the prevalence and outcomes of lung transplant recipients after prior cardiac surgery. MethodsLung transplants were identified from the United Network for Organ Sharing/Organ Procurement and Transplantation Network Database. Patients were stratified based on prior cardiac surgery (No Surgery [NS], Prior coronary artery bypass grafting [CABG], Prior Valve [Valve]). Unadjusted comparisons were performed amongst all groups, and propensity matching was utilized for adjusted comparisons. Survival was examined with Kaplan-Meier methods. Results28,710 patients were identified, 467 (1.6%) had prior CABG and 84 (0.3%) had prior valvular surgery. Prior to matching, the NS group was significantly younger, less commonly male, and had lower lung allocation scores. There were significantly fewer bilateral lung transplants in the CABG and Valve groups. Length of stay was shortest in the CABG group, but there were no significant differences in postoperative stroke, dialysis, or in-hospital mortality. There was an increased incidence of cardiac/cerebrovascular cause of death in CABG recipients (18.3%) and malignancy death in Valve recipients (23.3%). Following matching, CABG 5-year survival was lower than NS (p<0.01), while there was no significant difference between NS and Valve groups (p=0.4). ConclusionsCABG and Valve recipients had decreased survival, however not at levels prohibitive to transplantation. Due to potentially increased risk of cardiovascular mortality, providers should evaluate the burden of vascular disease in potential recipients with prior CABG to improve patient selection and maximize post-transplant survival.

(357) - The Second Time Around: Re-Evaluating Lung Retransplant Outcomes in the Lung Allocation Score Era

(357) - The Second Time Around: Re-Evaluating Lung Retransplant Outcomes in the Lung Allocation Score Era

Two single lung transplantations from one donor: lung twinning in the LAS era.

The implementation of the Lung Allocation Score (LAS) in the Eurotransplant international collaborative framework decreased waiting list mortality, but organ shortage remains a significant problem. Transplantation of two single lungs from one donor into two recipients (lung twinning) may decrease waiting list mortality. We sought to analyze if this strategy can lead to an acceptable intermediate-term outcome. Since the LAS-implementation we performed 32 paired single-lung transplantations from 16 postmortal donors. Data and outcome were analyzed retrospectively comparing recipients receiving the first lung (first twins) with recipients receiving the second lung (second twins), left versus right transplantation and restrictive versus obstructive disease. Survival at one year was 81% and 54% at five years. Veno-venous ECMO had been successfully used as bridge-to-transplant in three patients with ECMO-explantation immediately after surgery. Bronchial anastomotic complications were not observed in any patient. First twins and second twins exhibited similar survival (p = 0.82) despite higher LAS in first twins (median 45 versus 34, p < 0.001) and longer cold ischemic time in second twins (280 ± 83 vs. 478 ± 125min, p < 0.001). Survival of left and right transplantation was similar (p = 0.45) with similar best post-transplant FEV1 (68 ± 15% versus 62 ± 14%, p = 0.26). Survival was similar in restrictive and obstructive disease (p = 0.28) with better post-transplant FEV1 (70 ± 15% versus 57 ± 11%, p = 0.02) in restrictive disease. Performing two single-lung transplantations from one donor can be performed safely with encouraging intermediate-term outcome and good functional capacity. Lung twinning maximizes the donor pool and may help to overcome severe organ shortage. This research is not a clinical trial. Thus no registration details will be provided.

The Risk of Pretransplant Blood Transfusion for Primary Graft Dysfunction After Lung Transplant

BackgroundPrimary graft dysfunction (PGD) is the leading cause of short- and long-term mortality associated with lung transplantation. The impact of pretransplantation blood transfusions for recipients is not fully elucidated. MethodsThis is a retrospective review of 206 consecutive lung transplantations performed at a single academic center (Northwestern University Feinberg School of Medicine, Chicago, IL) from January 2018 to July 2022. Data on patient characteristics, pretransplantation laboratory values, transfusion requirements, and intraoperative and postoperative outcomes were collected. ResultsPGD grade 3 (PGD 3) occurred in 13.2% of the cohort (n = 28). A total of 33 patients received a blood transfusion within 4 weeks, whereas 21 patients received a blood transfusion a week before their lung transplant. Pretransplantation transfusions were strongly associated with a higher incidence of PGD 3 (48.5% vs 6.9%; P < .001). There was no significant difference in 1-year survival between the pretransplantation transfused group and the nontransfused group (77.7% vs 88.0%; P = .478). The 1year survival was reduced in recipients with PGD 3 compared with recipients without PGD 3 (63.5% vs 89.9%; P = .0012). In univariate analysis, pretransplant and intratransplant predictors of PGD 3 included younger age (P < .01), pretransplant extracorporeal membrane oxygenation (ECMO) use (P < .001), higher lung allocation score (P < .001), coronavirus disease 2019 (COVID-19)–related acute respiratory distress syndrome (P < .01), blood transfusion within 4 weeks (P < .001), longer operative time (P < .001), intratransplant blood transfusion (P < .001), and intratransplant venoarterial ECMO use (P < .001). ConclusionsPretransplantation blood transfusions could be associated with a higher rate of PGD. The findings indicated the potential risks of pretransplantation blood transfusions in lung transplant recipients.

Outcomes after lung transplantation from selected donors older than 70 years in a single centre: time to close the debate?

The aim of this study was to compare the outcomes of lung transplantations using grafts from donors aged over 70 years against those performed using younger donors. This retrospective single-centre analysis includes lung transplants conducted at our institution from January 2014 to June 2022. Lung recipients were classified into 2 groups based on donor age (group A <70 years; group B ≥70 years). Variables regarding demographics, peri and postoperative outcomes and survival were included. The statistical analysis approach included univariable analysis, propensity score matching to address imbalances in donor variables (smoking status), recipient characteristics (sex, age, diagnosis and lung allocation score) and calendar period and survival analysis. A total of 353 lung transplants were performed in this period, 47 (13.3%) using grafts from donors aged over 70 years. Donors in group B were more frequently women (70.2% vs 51.6%, P = 0.017), with less smoking history (22% vs 43%, P = 0.002) and longer mechanical ventilation time (3 vs 2 days, P = 0.025). Recipients in group B had a higher lung allocation score (37.5 vs 35, P = 0.035). Postoperative variables were comparable between both groups, except for pulmonary function tests. Group B demonstrated lower forced expiratory volume 1 s levels (2070 vs 2580 ml, P = 0.001). The propensity score matching showed a lower chance of chronic lung allograft dysfunction by 12% for group B. One-, three- and five-year survival was equal between the groups. The use of selected expanded-criteria donors aged over 70 years did not result in increased postoperative morbidity, early mortality or survival in this study.

Impact of minimally invasive lung transplantation on early outcomes and analgesia use: A matched cohort study

IntroductionMinimally invasive (MI) approaches to lung transplantation (LTx) offer the prospect of faster recovery compared to traditional incisions, however, little data exist describing the impact of surgical technique on early outcomes and analgesia use. MethodsA prospectively maintained institutional registry identified 170 patients who underwent LTx between 01/2017 and 06/2022. Post-COVID acute respiratory distress syndrome, repeat, and multiorgan transplants were excluded (n=27) leaving 37 MILTx and 106 traditional LTx patients. Propensity score matching by age, sex, body mass index, diagnosis, lung allocation score, double vs. single lung, hypertension, diabetes, and hospitalization status created 37 pairs. ResultsBefore matching, MILTx patients were more often male (70% vs 43%) and more likely to receive grafts from younger (31 vs 42 years), circulatory death donors (19% vs 6%) compared with traditional LTx patients (all p<0.05). After matching, there were no differences in graft warm ischemia or operative duration (both p>0.05). Postoperatively, MILTx experienced shorter ICU (4.3 [IQR 3.1-5.5] vs 8.2 [IQR 3.7-10.8] days) and hospital lengths of stay (LOS) (13 [IQR 11-15] vs 17 [IQR 12-25] days) (both p<0.05). Among patients surviving to discharge, MILTx patients required fewer opioid prescriptions at discharge (38% vs 66%, p=0.008) and had improved pulmonary function at 3-months (FEV1 82 [IQR 72-102] vs 77 [IQR 52-88] % predicted; FVC 78 [IQR 65-92] vs 70 [IQR 62-80] % predicted] (both p<0.05). ConclusionMinimally invasive LTx techniques demonstrate potential advantages over traditional approaches, including reduced ICU and hospital LOS, lower opioid use on discharge, and improved early pulmonary function. Word count: 250/250

Ambulatory Extracorporeal Membrane Oxygenation Use in Patients Listed for Lung Transplant.

There has been an increase in the use of extracorporeal membrane oxygenation (ECMO) to bridge critically ill patients to lung transplant (LTX). This study evaluates how ambulatory status on ECMO affected waitlist and post-LTX outcomes. The United Network of Organ Sharing (UNOS) database was queried for patients aged of greater than or equal to 18 years and between 2016 and 2021 to identify pre-LTX patients supported by ECMO. The patients were classified in venous-arterial (VA) ECMO and veno-venous (VV) ECMO cohorts and further classified as ambulatory (AMB) and non-AMB (nAMB). Each cohort was controlled against the non-ECMO patients. Univariate statistical tests, as well as Kaplan-Meier survival curves, were used for analysis. The 90 day waitlist survival was the highest among the non-ECMO group (96%), but both AMB VV and VA groups had superior survival compared to the nAMB group (85% vs. 75%, 78% vs. 65%, p < 0.01). After adjusting for the median lung allocation score (LAS) (88) in the VV ECMO group, the waitlist survival was superior in the AMB VV ECMO compared to those not on ECMO (86% vs. 78%, p > 0.01). The 1 year post-LTX survival between non-ECMO and AMB VV ECMO was comparable (88% vs. 88%, p = 0.66). Ambulating patients or use of physical therapy while on ECMO can help improve lung transplant outcomes.

Lung transplantation in HIV seropositive recipients: An analysis of the UNOS registry.

Experience with lung transplantation (LT) in patients with human immunodeficiency virus (HIV) is limited. Many studies have demonstrated the success of kidney and liver transplantation in HIV-seropositive (HIV+) patients. Our objective was to conduct a national registry analysis comparing LT outcomes in HIV+ to HIV-seronegative (HIV-) recipients. The United Network for Organ Sharing database was queried to identify LTs performed in adult HIV+ patients between 2016 and 2023. Patients with unknown HIV status, multiorgan transplants, and redo transplants were excluded. The primary endpoints were mortality and graft rejection. Survival time was analyzed using Kaplan-Meier analysis. The study included 17487 patients, 67 of whom were HIV+. HIV+ recipients were younger (59 vs. 62years, p=.02), had higher pulmonary arterial pressure (28 vs. 25mm Hg, p=.04), and higher lung allocation scores (47 vs. 41, p=.01) relative to HIV- recipients. There were no differences in graft/recipient survival time between groups.HIV+ recipients had higher rates of post-transplant dialysis (18% vs. 8.4%, p=.01), but otherwise had similar post-transplant outcomes to HIV-recipients. This national registry analysis suggests LT outcomes in HIV+ patients are not inferior to outcomes in HIV- patients and that well-selected HIV+ recipients can achieve comparable patient and graft survival rates relative to HIV- recipients.

Evaluation of the Current Urgency-Based Lung Allocation System in Korea with Simulation of the Eurotransplant Lung Allocation Score.

Due to the shortage of lung donors relative to the number of patients waiting for lung transplantation (LTx), more than one-third of patients on the waitlist have died without receiving LTx in Korea. Therefore, the importance of fair and effective allocation policies has been emphasized. This study investigated the characteristics of the current urgency-based allocation system in Korea by simulating the Eurotransplant lung allocation score (ET-LAS) using a nationwide multi-institutional registry for LTx in Korea. This study used data from the Korean Organ Transplantation Registry (KOTRY), along with additional retrospective data for ET-LAS calculation. A total of 194 patients were included in this study between January 2015 and December 2019. The Korean urgency definition classifies an LTx candidate as having statuses 0-3 according to urgency. The ET-LAS was analyzed according to the Korean urgency status. In total, 92 patients received lung transplants at status 0, 85 at status 1, and 17 at status 2/3. The ET-LAS showed a bimodal distribution with distinct peaks corresponding to status 0 and non-status 0. There was no significant difference in the ET-LAS among non-status 0 patients. In logistic and decision tree analyses, oxygen supplementation methods, particularly oxygen masks and high-flow nasal cannulas, were significantly associated with a high ET-LAS (≥50) among non-status 0 patients. Simulation of the ET-LAS with KOTRY data showed that the Korean urgency definition may not allocate lungs by urgency, especially for patients in non-status 0; therefore, it needs to be revised.