Donor Lung Preservation at 10°C: Clinical and Logistical Impact.

INTRODUCTION: Cold static donor lung preservation at 10°C appears to be a promising method to safely extend the cold ischemic time (CIT) and improve lung transplant (LTx) logistics. METHODS: LTx from November 2021 to February 2023 were included in this single institution, prospective, non-randomized study comparing prolonged preservation at 10°C versus standard preservation on ice. The inclusion criteria for 10°C preservation were suitable grafts for LTx without any donor retrieval concerns. PRIMARY ENDPOINT: primary graft dysfunction (PGD) grade-3 at 72-h. Secondary endpoints: clinical outcomes, cytokine profile and logistical impact. RESULTS: Thirty-three out of fifty-seven cases were preserved at 10°C. Donor and recipient characteristics were similar across the groups. Total preservation times (h:min) were longer (p<0.001) in the 10°C group [1st lung: median 12:09 (IQR 9:23-13:29); 2nd: 14:24 (12:00-16:20)] vs. standard group [1st lung: median 5:47 (IQR 5:18-6:40); 2nd: 7:15 (6:33-7:40)]. PGD grade-3 at 72-h was 9.4% in 10°C group vs. 12.5% in standard group (p=0.440). Length of mechanical ventilation (MV), ICU and hospital stays were similar in both groups. Thirty and ninety-day mortality rates were 0% in 10°C group (vs. 4.2% in standard group). IL-8 concentration was significantly higher 6-h post-LTx in the standard group (p=0.025) and IL-10 concentration was increased 72-h post-LTx in the 10°C group (p=0.045). CONCLUSIONS: Preservation at 10°C may represent a safe and feasible strategy to intentionally prolong the CIT. In our center, extending the CIT at 10°C may allow for semi-elective LTx and improve logistics with similar outcomes compared to the current standard preservation on ice.

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

OBJECTIVES: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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 Pleural Lavage Cytology Positivity on Early Recurrence After Surgery for Non-Small Cell Lung Cancer.

OBJECTIVE: The aim of this study was to elucidate the impact of pleural lavage cytology positivity on early recurrence in patients operated on non-small cell lung cancer (NSCLC). METHODS: This is a multicentre prospective cohort study of 684 patients undergoing an anatomical lung resection for NSCLC between October 2015 and October 2017 at 12 national centres. A pleural lavage was performed before and after lung resection. The association between the different predictors of early recurrence and PLC positivity was performed using univariate and multivariate logistic regression models. A propensity score analysis was performed by inverse probability weighting (IPSW) using average treatment effect (ATE) estimation to analyse the impact of PLC positivity on early recurrence. RESULTS: Overall PLC positivity was observed in 15 patients (2.2%). After two years, 193 patients (28.2%) relapsed, 182 (27.2%) with a negative PLC and 11 (73.3%) with a positive PLC (p<0.001). Factors associated to early recurrence were adenocarcinoma histology (OR=1.59, 95%CI 1.06-2.38, p=0.025), visceral pleural invasion (OR=1.59, 95%CI 1.04-2.4, p=0.03), lymph node involvement (OR=1.84, 95%CI 1.14-2.96, p=0.013), advanced pathological stage (OR=2.12, 95%CI 1.27-3.54, p=0.004) and PLC positivity (OR=4.14, 95%CI 1.25-16.36, p=0.028). After IPSW, PLC positivity was associated with an increased risk of early recurrence (OR=3.46, 95%CI 2.25-5.36, p<0.001). CONCLUSIONS: Positive pleural lavage cytology was found to be the strongest predictor of early recurrence.

Pathological N1/N2 in Clinical Stage I Bronchogenic Carcinoma. Analysis From a Prospective Multicentre Database.

OBJECTIVES: To determine the incidence of occult N1/N2 nodal metastases and associated risk factors in patients with non-small cell lung cancer no larger than 3cm and deemed cN0 by CT and PET-CT in a prospective, multicentre national database. METHODS: Patients with a NSCLC no larger than 3cm, deemed cN0 by PET-CT and CT scan, who had undergone at least a lobectomy, were selected from a national multicentre database of 3533 patients who had undergone anatomic lung resection between 2016 and 2018. Clinical and pathological variables of patients with pN0 and patients with pN1/N2 were compared to identify factors associated with the presence of lymph node metastases. Chi2 and the Mann-Whitney U test were used for categorical and numerical variables, respectively. All variables with p<0.2 in the univariate analysis were included in the multivariate logistic regression analysis. RESULTS: The study included 1205 patients from the cohort. The incidence of occult pN1/N2 disease was 10.70% (95%CI, 9.01-12.58). The multivariable analysis revealed that the degree of differentiation, size, location (central or peripheral) and SUV of the tumour in PET, surgeon experience and number of lymph nodes resected were associated with occult N1/N2 metastases. CONCLUSIONS: The incidence of occult N1/N2 in patients with bronchogenic carcinoma with cN0 tumours no larger than 3cm is no negligible. Data about the degree of differentiation, tumour size in CT scan, maximal uptake of the tumour in PET-CT, location (central or peripheral), number of lymph nodes resected and surgeon seniority is relevant in order to detect patients at risk.

Donor lungs cold preservation at 10 °C offers a potential logistic advantage in lung transplantation.

Donor lung preservation at 10 °C appears to be an innovative and promising method that may improve transplant logistics by extending the cold ischemia time with excellent outcomes. We report the case of two lung transplants from two different donors involving the use of two different preservation methods, highlighting the benefits of using 10 °C lung storage.

Interrupted versus continuous suture for bronchial anastomosis in lung transplantation: does it matter?

OBJECTIVES: Bronchial anastomotic complications remain a major concern in lung transplantation. We aim to compare 2 different techniques, continuous suture (CS) versus interrupted suture (IS) by analysing airway complications requiring intervention. METHODS: Lung transplantations between January 2015 and December 2020 were included. Airway complications requiring intervention were classified following the 2018 International Society for Heart and Lung Transplantation consensus and analysed comparing 3 groups of patients according to surgical technique: group A, both anastomosis performed with CS; group B, both with interrupted; and group C, IS for 1 side and CS for the contralateral side. RESULTS: A total of 461 anastomoses were performed in 245 patients. The incidence of airway complications requiring intervention was 5.7% [95% confidence interval (CI): 2.8-8.6] per patient (14/245) and 3.7% (95% CI: 2.0-5.4) per anastomosis (17/461). Complications that required intervention were present in 5 out of 164 (3.1%) anastomosis with interrupted technique, and in 12/240 (5%) with CS. No significant differences were found between techniques (P = 0.184). No statistical differences were found among group A, B or C in terms of incidence of anastomotic complications, demographics, transplant outcomes or overall survival (log-rank P = 0.513). In a multivariable analysis, right laterality was significantly associated to complications requiring intervention (OR 3.7 [95% CI: 1.1-12.3], P = 0.030). Endoscopic treatment was successful in 12 patients (85.7%). Retransplantation was necessary in 2 patients. CONCLUSIONS: In summary, although it seems that anastomotic complications requiring intervention occur more frequently with CS, there are no statistical differences compared to IS. Endoscopic treatment offers good outcomes in most of the airway complications after lung transplantation.

Predictive factors of pathological complete response after induction (ypT0N0M0) in non-small cell lung cancer and short-term outcomes: Results of the Spanish Group of Video-assisted Thoracic Surgery (GE-VATS).

INTRODUCTION: To analyze the predictors of pCR in NSCLC patients who underwent anatomical lung resection after induction therapy and to evaluate the postoperative results of these patients. METHODS: All patients prospectively registered in the database of the GE-VATS working group undergone anatomic lung resection by NSCLC after induction treatment and recruited between 12/20/2016 and 3/20/2018 were included in the study. The population was divided into two groups: patients who obtained a complete pathological response after induction (pCR) and patients who did not obtain a complete pathological response after induction (non-pCR). A multivariate analysis was performed using a binary logistic regression to determine the predictors of pCR and the postoperative results of patients were analyzed. RESULTS: Of the 241 patients analyzed, 36 patients (14.9%) achieved pCR. Predictive factors for pCR are male sex (OR: 2.814, 95% CI: 1.015-7.806), histology of squamous carcinoma (OR: 3.065, 95% CI: 1.233-7.619) or other than adenocarcinoma (OR: 5.788, 95% CI: 1.878-17.733) and induction therapy that includes radiation therapy (OR: 4.096, 95% CI: 1.785-9.401) and targeted therapies (OR: 7.625, 95% CI: 2.147-27.077). Prevalence of postoperative pulmonary complications was higher in patients treated with neoadjuvant chemo-radiotherapy (p = 0.032). CONCLUSIONS: Male sex, histology of squamous carcinoma or other than ADC, and induction therapy that includes radiotherapy or targeted therapy are positive predictors for obtaining pCR. Induction chemo-radiotherapy is associated with a higher risk of postoperative pulmonary complications.

External validation of the European Society of Thoracic Surgeons morbidity and mortality risk models.

OBJECTIVES: There is a wide variety of predictive models of postoperative risk, although some of them are specific to thoracic surgery, none of them is widely used. The European Society for Thoracic Surgery has recently updated its models of cardiopulmonary morbidity (Eurolung 1) and 30-day mortality (Eurolung 2) after anatomic lung resection. The aim of our work is to carry out the external validation of both models in a multicentre national database. METHODS: External validation of Eurolung 1 and Eurolung 2 was evaluated through calibration (calibration plot, Brier score and Hosmer-Lemeshow test) and discrimination [area under receiver operating characteristic curves (AUC ROC)], on a national multicentre database of 2858 patients undergoing anatomic lung resection between 2016 and 2018. RESULTS: For Eurolung 1, calibration plot showed suboptimal overlapping (slope = 0.921) and a Hosmer-Lemeshow test and Brier score of P = 0.353 and 0.104, respectively. In terms of discrimination, AUC ROC for Eurolung 1 was 0.653 (95% confidence interval, 0.623-0.684). In contrast, Eurolung 2 showed a good calibration (slope = 1.038) and a Hosmer-Lemeshow test and Brier score of P = 0.234 and 0.020, respectively. AUC ROC for Eurolung 2 was 0.760 (95% confidence interval, 0.701-0.819). CONCLUSIONS: Thirty-day mortality score (Eurolung 2) seems to be transportable to other anatomic lung-resected patients. On the other hand, postoperative cardiopulmonary morbidity score (Eurolung 1) seems not to have sufficient generalizability for new patients.

Treatment and intention-to-treat propensity score analysis to evaluate the impact of video-assisted thoracic surgery on 90-day mortality after anatomical resection for lung cancer.

OBJECTIVES: The aim of this study was to know the treatment effect of video-assisted thoracic surgery (VATS) on 90-day mortality after anatomical lung resection based on a nationwide cohort. METHODS: This is a multicentre prospective cohort of 2721 anatomical resections for lung cancer from December 2016 to March 2018. Treatment and intention-to-treat (ITT) analyses were performed after inverse probability score weighting and different propensity score matching algorithms. Covariate balance was assessed by standardized mean differences. The estimators reported were the average treatment effect, the average treatment effect on the treated and odds ratios after conditional logistic models with 95% confidence intervals. The unconfoundedness assumption was evaluated by sensitivity analysis for average treatment effect (c-dependence) and average treatment effect on the treated (Γ). RESULTS: VATS was the initial approach in 1911 patients (70.2%), though 273 cases (14.3%) had to be converted to thoracotomy. Ninety-day mortality rates were: treatment analysis (VATS 1.16% vs open 3.9%, P < 0.001), ITT analysis (VATS 1.78% vs open 3.36%, P = 0.012). After inverse probability score weighting and propensity score matching, in the treatment analysis, VATS meant absolute risk reductions between 2.25% and 2.96% and relative risk reductions between 65% and 70% [OR = 0.34 (95% confidence interval 0.15-0.79), all P-values <0.004). However, all the estimators turned out to be non-significant in the ITT analyses. A high sensitivity to unobservable confounders was proved (c-dependence 0.135, Γ = 1.5). CONCLUSIONS: VATS can reduce the risk of 90-day mortality after anatomical lung resection. However, the implications of conversion to thoracotomy, comparing ITT versus treatment analysis, and the potential impact of hidden bias should deserve further attention in the future.

Radicality of lymphadenectomy in lung cancer resections by thoracotomy and video-assisted thoracoscopic approach: A prospective, multicentre and propensity-score adjusted study.

OBJECTIVE: To analyse differences in intraoperative nodal assessment in patients undergoing lung cancer resection by thoracotomy and video-assisted thoracoscopy (VATS) in the Spanish Video-Assisted Thoracic Surgery Group (GEVATS). METHODS: Prospective multicentre cohort study of anatomic pulmonary resections (n = 3533) performed from December 2016 to March 2018. Main surgical, clinical and oncological variables related with lymphadenectomy were compared according to surgical approach. Corresponding tests for homogeneity were performed. Multiple logistic regression analyses were used to determine the odds ratio (OR) and 95% confidence interval (95%CI). Covariate adjustment using the propensity score (PS) was performed to reduce confounding effects. RESULTS: After exclusions, 2532 patients were analysed. Systematic nodal dissection (SND) was performed in 65%, with a median of resected/sampled lymph nodes (LN) of 7 (IQR 4-12) and pathologic (p) N2 and uncertain (u) pNu rates of 9.4% and 28.9%, respectively. At multivariate analysis, the following were associated with thoracotomy (OR; 95%CI): SND (1.4; 1.08-1.96; p = 0.014), staging mediastinoscopy (2.6; 1.59-4.25; p < 0.001), tumor > 3 cm (2.1; 1.66-2.78; p < 0.001), central tumor (2.5; 1.90-3.24; p < 0.001); pN1 (1.8; 1.25-2.67; p < 0.002), pN2 (1.8; 1.18-2.76; p = 0.006), lower FEV1 (0.9; 0.98-0.99; p < 0.001), squamous cell carcinoma (1.5; 1.16-1.98; p = 0.002) and inexperienced surgeons in VATS (compared with > 100 VATS experience) (37.6; 13.55-104.6; p < 0.001). After PS adjustment, SND maintained the OR, but in the limit of signification (1.4; 1-1.98; p = 0.05). Nodal upstaging was significantly higher in the thoracotomy group. Complication rates of SND and no SND were similar. CONCLUSIONS: Thoracotomy was associated with a more thorough lymphadenectomy in GEVATS. Therefore, intraoperative lymph node evaluation performed at VATS should be improved to have better prognostic information and more solid grounds to indicate adjuvant therapy.

Surgical Risk Following Anatomic Lung Resection in Thoracic Surgery: A Prediction Model Derived from a Spanish Multicenter Database. / Riesgo quirúrgico tras resección pulmonar anatómica en cirugía torácica. Modelo predictivo a partir de una base de datos nacional multicéntrica.

INTRODUCTION: The aim of this study was to develop a surgical risk prediction model in patients undergoing anatomic lung resections from the registry of the Spanish Video-Assisted Thoracic Surgery Group (GEVATS). METHODS: Data were collected from 3,533 patients undergoing anatomic lung resection for any diagnosis between December 20, 2016 and March 20, 2018. We defined a combined outcome variable: death or Clavien Dindo grade IV complication at 90 days after surgery. Univariate and multivariate analyses were performed by logistic regression. Internal validation of the model was performed using resampling techniques. RESULTS: The incidence of the outcome variable was 4.29% (95% CI 3.6-4.9). The variables remaining in the final logistic model were: age, sex, previous lung cancer resection, dyspnea (mMRC), right pneumonectomy, and ppo DLCO. The performance parameters of the model adjusted by resampling were: C-statistic 0.712 (95% CI 0.648-0.750), Brier score 0.042 and bootstrap shrinkage 0.854. CONCLUSIONS: The risk prediction model obtained from the GEVATS database is a simple, valid, and reliable model that is a useful tool for establishing the risk of a patient undergoing anatomic lung resection.

Lung transplantation from uncontrolled and controlled donation after circulatory death: similar outcomes to brain death donors.

Controlled donation after circulatory death donors (cDCD) are becoming a frequent source of lungs grafts worldwide. Conversely, lung transplantations (LTx) from uncontrolled donors (uDCD) are sporadically reported. We aimed to review our institutional experience using both uDCD and cDCD and compare to LTx from brain death donors (DBD). This is a retrospective analysis of all LTx performed between January 2013 and December 2019 in our institution. Donor and recipient characteristics were collected and univariate, multivariate and survival analyses were carried out comparing the three cohorts of donors. A total of 239 (84.7%) LTx were performed from DBD, 29 (10.3%) from cDCD and 14 (5%) from uDCD. There were no statistically significant differences in primary graft dysfunction grade 3 at 72 h, 30- and 90-day mortality, need for extracorporeal membrane oxygenation after procedure, ICU and hospital length of stay, airway complications, CLAD incidence or survival at 1 and 3 years after transplant (DBD: 87.1% and 78.1%; cDCD: 89.7% and 89.7%; uDCD: 85.7% and 85.7% respectively; P = 0.42). Short- and mid-term outcomes are comparable between the three types of donors. These findings may encourage and reinforce all types of donation after circulatory death programmes as a valid and growing source of suitable organs for transplantation.

Predictive factors of pathological complete response after induction (ypT0N0M0) in non-small cell lung cancer and short-term outcomes: results of the Spanish Group of Video-assisted Thoracic Surgery (GE-VATS). / Factores predictores de respuesta completa patológica tras inducción (ypT0N0M0) en cáncer de pulmón no microcítico y resultados a corto plazo: resultados del Grupo Español de Cirugía Torácica Videoasistida (GE-VATS).

INTRODUCTION: To analyze the predictors of pathological complete response (pCR) in not small cells lung carcinoma (NSCLC) patients who underwent anatomical lung resection after induction therapy and to evaluate the postoperative results of these patients. METHODS: All patients prospectively registered in the database of the GE-VATS working group undergone anatomic lung resection by NSCLC after induction treatment and recruited between December 20th 2016, and March 20th 2018, were included in the study. The population was divided into two groups: patients who obtained a complete pathological response after induction (pCR) and patients who did not obtain a complete pathological response after induction (non-pCR). A multivariate analysis was performed using a binary logistic regression to determine the predictors of pCR and the postoperative results of patients were analyzed. RESULTS: Of the 241 patients analyzed, 36 patients (14.9%) achieved pCR. Predictive factors for pCR are male sex (OR 2.814, 95% CI 1.015-7.806), histology of squamous carcinoma (OR 3.065, 95% CI 1.233-7.619) or other than adenocarcinoma (ADC) (OR 5.788, 95% CI 1.878-17.733) and induction therapy that includes radiation therapy (OR 4.096, 95% CI 1.785-9.401) and targeted therapies (OR 7.625, 95% CI 2.147-27.077). Prevalence of postoperative pulmonary complications was higher in patients treated with neoadjuvant chemo-radiotherapy (p = 0.032). CONCLUSIONS: Male sex, histology of squamous carcinoma or other than ADC, and induction therapy that includes radiotherapy or targeted therapy are positive predictors for obtaining pCR. Induction chemo-radiotherapy is associated with a higher risk of postoperative pulmonary complications.

Effect on the donor lungs of using abdominal normothermic regional perfusion in controlled donation after circulatory death.

OBJECTIVES: Controlled donation after circulatory death (cDCD) donors are becoming a common source of organs for transplantation globally. However, the graft survival rate of cDCD abdominal organs is inferior to that of organs from brain-dead donors. The rapid retrieval (RR) technique is used by most donor organ procurement teams. The abdominal normothermic regional perfusion (A-NRP) technique has been implemented to minimize warm ischaemic damage to the abdominal organs. However, there is limited information on the effect of A-NRP on the quality of the donor lungs. This study aimed to compare lung transplantation outcomes using lungs procured from cDCD donors using the A-NRP and abdominal RR techniques. METHODS: A single-centre retrospective analysis of consecutive transplant recipients of cDCD lungs from June 2013 to December 2019 was performed. The recipients were divided into 2 cohorts according to the abdominal procurement technique used. The recipient and donor characteristics (age, sex, cause of brain injury, warm ischaemic time, diagnosis, lung allocation score and other factors), incidence of primary graft dysfunction and early survival were monitored. RESULTS: Twenty-eight consecutive lung transplantation recipients were identified (median age 59 years; 61% male); 14 recipients received lungs using the A-NRP and 14 using abdominal RR for abdominal organ retrieval. There were no significant differences in the baseline characteristics, primary graft dysfunction (P = 0.70), hospital mortality (P = 1.0) and 1-year survival rate (P = 1.0) between the 2 groups. CONCLUSIONS: No difference was observed in lung transplantation outcomes irrespective of the abdominal organ procurement technique used (A-NRP or abdominal RR).

Thoracic surgery during the coronavirus disease 2019 (COVID-19) pandemic in Madrid, Spain: single-centre report.

OBJECTIVES: We reviewed the incidence of coronavirus disease 2019 cases and the postoperative outcomes of patients who had thoracic surgery during the beginning and at the highest point of transmission in our community. METHODS: We retrospectively reviewed patients who had undergone elective thoracic surgery from 12 February 2020 to 30 April 2020 and were symptomatic or tested positive for severe acute respiratory syndrome coronavirus 2 infection within 14 days after surgery, with a focus on their complications and potential deaths. RESULTS: Out of 101 surgical procedures, including 57 primary oncological resections, 6 lung transplants and 18 emergency procedures, only 5 cases of coronavirus disease 2019 were identified, 3 in the immediate postoperative period and 2 as outpatients. All 5 patients had cancer; the median age was 64 years. The main virus-related symptom was fever (80%), and the median onset of coronavirus disease 2019 was 3 days. Although 80% of the patients who had positive test results for severe acute respiratory syndrome coronavirus 2 required in-hospital care, none of them were considered severe or critical and none died. CONCLUSIONS: These results indicate that, in properly selected cases, with short preoperative in-hospital stays, strict isolation and infection control protocols, managed by a dedicated multidisciplinary team, a surgical procedure could be performed with a relatively low risk for the patient.

Spanish Video-Assisted Thoracic Surgery Group: Method, Auditing, and Initial Results From a National Prospective Cohort of Patients Receiving Anatomical Lung Resections.

INTRODUCTION: Our study sought to know the current implementation of video-assisted thoracoscopic surgery (VATS) for anatomical lung resections in Spain. We present our initial results and describe the auditing systems developed by the Spanish VATS Group (GEVATS). METHODS: We conducted a prospective multicentre cohort study that included patients receiving anatomical lung resections between 12/20/2016 and 03/20/2018. The main quality controls consisted of determining the recruitment rate of each centre and the accuracy of the perioperative data collected based on six key variables. The implications of a low recruitment rate were analysed for "90-day mortality" and "Grade IIIb-V complications". RESULTS: The series was composed of 3533 cases (1917 VATS; 54.3%) across 33 departments. The centres' median recruitment rate was 99% (25-75th:76-100%), with an overall recruitment rate of 83% and a data accuracy of 98%. We were unable to demonstrate a significant association between the recruitment rate and the risk of morbidity/mortality, but a trend was found in the unadjusted analysis for those centres with recruitment rates lower than 80% (centres with 95-100% rates as reference): grade IIIb-V OR=0.61 (p=0.081), 90-day mortality OR=0.46 (p=0.051). CONCLUSIONS: More than half of the anatomical lung resections in Spain are performed via VATS. According to our results, the centre's recruitment rate and its potential implications due to selection bias, should deserve further attention by the main voluntary multicentre studies of our speciality. The high representativeness as well as the reliability of the GEVATS data constitute a fundamental point of departure for this nationwide cohort.

Bone Marrow-derived Mesenchymal Stem Cells and Chronic Allograft Disease in a Bronchiolitis Obliterans Animal Model.

INTRODUCTION: Bronchiolitis obliterans (BO) is the most common expression of chronic allograft dysfunction in lung transplantation. Moreover, BO represents the major cause of death in the long-term after this procedure. On the other hand, mesenchymal stem cells have been tested in animal models of BO aiming to interfere in its development. The aim of this experimental study is to explore the role of bone-marrow derived stem cells (BMSCs) as a preventive intervention of BO occurrence. MATERIALS AND METHODS: This an experimental randomized study. A bronchiolitis obliterans animal model in rats was reproduced: heterotopical tracheal transplant model in lung parenchyma. Five of these animals were used as control group. After setting up the model, individuals were divided in 3 groups of treatment (n=15), in which BMSCs were administered in 3 different time points after the tracheal transplant (tracheal transplantation and BMSCs administration occurred the same day, group G0; after 7 days, group G7; after 14 days, group G14. In addition, within each group, BMSCs were administered through 3 different routes: endotracheally, endovascular and topically in the lung parenchyma). Animals were sacrificed at 21 days. Histology, fluorescence in situ hybridization and immunohistochemistry techniques were performed for identifying stem cells. RESULTS: Compared to control group, animals receiving BMSCs showed large neovessels in a loose fibrous matrix. Group G7 showed less fibrosis (p<0.033) and edema (p<0.028). Moreover, G7 animals receiving stem cells endotracheally showed no fibrosis (p<0.008). Alveolar-like patches of tissue were observed among all groups (53.4%, 46.7% and 40% in G0, G7 and G14 respectively), consisting of cells expressing both stem and alveolar cells biomarkers. CONCLUSION: BMSCs modify the course of bronchiolitis obliterans and differentiate into alveolar cells. Endotracheal administration of BMSCs 7 days after the heterotopical tracheal transplant might be considered an effective way to prevent BO in this animal model.

Expanding the horizons: Uncontrolled donors after circulatory death for lung transplantation-First comparison with brain death donors.

Uncontrolled donation after cardiac death is an appealing source of organs for lung transplantation. We compare early and long-term outcomes of lung transplantation with these donors with a cohort of transplants from brain death donors at our institution. Retrospective analysis of all lung transplantations was performed from 2002 to 2012. We collected variables regarding recipients, donors, recover and transplant procedures, early and late complications, and survival. We included 292 lung transplants from brain death donors and 38 from uncontrolled donors after cardiac death. Both groups were comparable except for sex mismatch (male recipient-female donor was more frequent in the brain death cohort, 17.8% vs 0%, P 0.002), total ischemic time (longer for donors after cardiac death, 657 minutes for the first lung and 822 minutes for the second vs 309 and 425 minutes, P < 0.001), and ex vivo evaluation (more frequent in cardiac death donors, 21.1% vs 1.4%, P < 0.001). Early and late outcomes were not different (ICU stay [9 vs 10.5 days], hospital stay [33.5 vs 35 days], primary graft dysfunction G3 [24 vs 34.2%], and chronic graft dysfunction HR 1.19 [0.61-2.32]), but overall survival was significantly lower for patients transplanted from cardiac death donors [HR 1.67 (1.06-2.64)]. Lung transplantation after uncontrolled cardiac death offers poorer results in terms of survival compared to brain death donation. Refinement of current strategies for graft preservation and evaluation is essential to improve outcomes with this source of grafts.