Extracorporeal membrane oxygenation after lung transplantation: risk factors and outcomes analysis

One-Year Mortality After Lung Transplantation: Experience of a Single French Center Between 2012 and 2021

BACKGROUND Lung transplantation (LTx) is a life-extending therapy for specific patients with terminal lung diseases. This study aimed to evaluate the associations and causes of 1-year mortality after lung transplantation at Strasbourg University Hospital, France, between 2012 and 2021. MATERIAL AND METHODS We carried out a retrospective analysis on 425 patients who underwent LTx at Strasbourg University Hospital between January 1, 2012, and December 31, 2021. Pre-transplant, perioperative, and postoperative data were collected from the electronic medical records. RESULTS Among all patients, 94.6% had a LTx, 4.0% a heart-lung transplantation, and 1.4% underwent pancreatic islet-lung transplantation. The median age at transplantation was 57 years, with 55.3% male patients. The main native lung disease leading to LTx was chronic obstructive pulmonary disease in 51.1% of patients; 16.2% needed super-urgent LTx. The 1-year mortality rate was 11.5%. Most deaths were either caused by multi-organ failure or septic shock. In our multivariate analysis, we identified 3 risk factors significantly related to 1-year mortality after LTx: body mass index (BMI) between 25 and 30 kg/m² vs BMI between 18.5 and 25 kg/m² (P=0.032), postoperative extracorporeal membrane oxygenation support (P=0.034), and intensive care unit length of stay after transplantation (P<0.001). Two other factors were associated with a significantly lower 1-year mortality risk: longer hospital stay after LTx (P=0.024) and tacrolimus prescription (P=0.004). CONCLUSIONS Our study reported a 1-year mortality rate of 11.5% after LTx. Although LTx candidates are carefully selected, additional data are required to improve understanding of the risk factors for post-LTx mortality.

A risk score for predicting extracorporeal membrane oxygenation support before lung transplantation

Background

Extracorporeal membrane oxygenation (ECMO) has been increasingly used as life support for lung transplantation. However, there are no clinical risk models to predict whether ECMO support is required for lung transplantation. This study developed a simple risk score to predict the need for intraoperative ECMO in patients undergoing lung transplantation, identify high-risk patients who need ECMO support, and guide clinical interventions.

Methods

Patients, who underwent lung transplantation between January 1, 2016 and July 31, 2021, were systematically reviewed. All enrolled patients were divided in a ratio of 7:3 to establish the development and validation datasets. A risk score model was established using stepwise logistic regression and verified using bootstrapping and the split-sample method.

Results

A total of 248 patients who underwent lung transplants were enrolled. Multivariate analysis showed that the primary disease diagnosis, pulmonary artery systolic pressure, sex, surgical type, creatine kinase isoenzyme-MB, and pro-B-type natriuretic peptide were risk factors for intraoperative ECMO during lung transplantation. The risk score was established and calibrated according to these six factors, ranging from 0 to 41, with the associated prediction of intraoperative use of ECMO ranging from 1.5% to 99.7% (Hosmer-Lemeshow χ2=5.624; P=0.689). Good discrimination was verified by developing and validating the datasets (C-statistics =0.850 and 0.842, respectively). Based on the distribution of the scores, the three levels were classified as low-risk (0-10], moderate-risk (10-20], and high-risk (20-41].

Conclusions

This simple risk score model effectively predicts the need for intraoperative ECMO and stratifies high-risk patients who require ECMO support.

Management of primary graft dysfunction after lung transplantation with extracorporeal life support: an evidence-based review

Primary graft dysfunction (PGD) is a complex inflammatory syndrome that can lead to respiratory failure after lung transplantation (LTx). The pathogenesis of PGD is multifactorial and can be driven by attributes of both the donor and recipient, perioperative characteristics, and technical handling of the graft. Despite significant advancements in patient and donor selection, perioperative management and surgical technique, PGD is still a major contributor to morbidity and mortality after lung transplant. Although there are no known durable treatment options for PGD after LTx, an increasing body of evidence and experience in high-volume lung transplant centers show that extracorporeal life support (ECLS) is a reliable option for both preventing PGD and supporting critically ill patients with PGD. Both veno-venous (V-V) ECLS and veno-arterial (V-A) ECLS are proven and feasible strategies for mitigating the morbidity and mortality associated with post-LTx PGD. In this evidence-based review, we provide an overview of the epidemiology and physiology of PGD as well as a growing body of data that supports ECLS as a major tool to manage PGD. We describe the role of ECMO in PGD prevention and management, worldwide outcomes of LTx with ECLS support, and outline our step-wise approach to managing this complex respiratory syndrome leading up to institution of ECLS.

The Future of Cardiothoracic Surgical Critical Care Medicine as a Medical Science: A Call to Action

Cardiothoracic surgical critical care medicine (CT-CCM) is a medical discipline centered on the perioperative care of diverse groups of patients. With an aging demographic and an increase in burden of chronic diseases the utilization of cardiothoracic surgical critical care units is likely to escalate in the coming decades. Given these projections, it is important to assess the state of cardiothoracic surgical intensive care, to develop goals and objectives for the future, and to identify knowledge gaps in need of scientific inquiry. This two-part review concentrates on CT-CCM as its own subspeciality of critical care and cardiothoracic surgery and provides aspirational goals for its practitioners and scientists. In part one, a list of guiding principles and a call-to-action agenda geared towards growth and promotion of CT-CCM are offered. In part two, an evaluation of selected scientific data is performed, identifying gaps in CT-CCM knowledge, and recommending direction to future scientific endeavors.

Extracorporeal membrane oxygenation support for lung transplantation: Initial experience in a single center in China and a literature review

Background

Extracorporeal membrane oxygenation (ECMO) is a versatile tool associated with favorable outcomes in the field of lung transplantation (LTx). Here, the clinical outcomes and complications of patients who underwent LTx with ECMO support, mainly prophylactically both intraoperatively and post-operatively, in a single center in China are reviewed.

Methods

The study cohort included all consecutive patients who underwent LTx between January 2020 and January 2022. Demographics and LTx data were retrospectively reviewed. Perioperative results, including complications and survival outcomes, were assessed.

Results

Of 86 patients included in the study, 32 received ECMO support, including 21 who received prophylactic intraoperative use of ECMO with or without prolonged post-operative use (pro-ECMO group), while the remaining 54 (62.8%) received no external support (non-ECMO group). There were no significant differences in the incidence of grade 3 primary graft dysfunction (PGD), short-term survival, or perioperative outcomes and complications between the non-ECMO and pro-ECMO groups. However, the estimated 1- and 2-year survival were superior in the pro-ECMO group, although this difference was not statistically significant (64.1% vs. 82.4%, log-rank P = 0.152; 46.5% vs. 72.1%, log-rank P = 0.182, respectively). After regrouping based on the reason for ECMO support, 30-day survival was satisfactory, while 90-day survival was poor in patients who received ECMO as a bridge to transplantation. However, prophylactic intraoperative use of ECMO and post-operative ECMO prolongation demonstrated promising survival and acceptable complication rates. In particular, patients who initially received venovenous (VV) ECMO intraoperatively with the same configuration post-operatively achieved excellent outcomes. The use of ECMO to salvage a graft affected by severe PGD also achieved acceptable survival in the rescue group.

Conclusions

Prophylactic intraoperative ECMO support and post-operative ECMO prolongation demonstrated promising survival outcomes and acceptable complications in LTx patients. Particularly, VV ECMO provided safe and effective support intraoperatively and prophylactic prolongation reduced the incidence of PGD in selected patients. However, since this study was conducted in a relatively low-volume transplant center, further studies are needed to validate the results.

Extracorporeal membrane oxygenation and lung transplantation

The use of extracorporeal membrane oxygenation has had a positive impact on the outcomes after lung transplantation. Extracorporeal membrane oxygenation has a role in all phases of lung transplantation-preoperative, intraoperative, and postoperative periods. It serves as a bridge to transplantation in appropriate patients awaiting lung transplantation. Extracorporeal membrane oxygenation is used as a preferred method of cardiopulmonary support in some centres during implantation; and, after lung transplantation, it can be used to salvage the implanted lung in cases of severe primary graft dysfunction or as a planned extension of intraoperative extracorporeal membrane oxygenation onto the postoperative period. It has now gained acceptance as a mandatory tool in most lung transplant units. This article reviews the history of extracorporeal membrane oxygenation and lung transplantation, their subsequent development, and the current use of extracorporeal membrane oxygenation during lung transplantation. Our institutional practice and experience are described. The implications of the current global coronavirus disease pandemic on extracorporeal membrane oxygenation and lung transplantation are also briefly discussed.

Preoperative risk factors for successful extubation or not after lung transplantation

Background

The purpose of this study was to uncover preoperative risk factors for extubation failure or re-intubation for patients undergoing lung transplant (LTx).

Methods

We performed a retrospective case-control study of LTx from our center between January 2017 and March 2019. Demographic and preoperative characteristics were collected for all included patients. Univariable analysis and multivariable logistic regression were used to analyze risk factors of postoperative unsuccessful extubation following LTx.

Results

Among 107 patients undergoing first LTx investigated, 74 (69.16%) patients who were successfully liberated from mechanical ventilation (MV), and 33 (30.84%) patients who were unsuccessful extubation, which 18 (16.82%) patients suffered from reintubation. associated preoperative factors for unsuccessful extubation following LTx included preoperative extracorporeal membrane oxygenation (ECMO) support [OR =4.631, 95% confidence interval (CI): 1.403–15.286, P=0.012], the preoperative ability of independent expectoration (OR =4.517, 95% CI: 1.498–13.625, P=0.007), the age older than 65-year-old (OR =4.039, 95% CI: 1.154–14.139, P=0.029), and receiving the double lung and heart-LTx (OR =3.390, 95% CI: 0.873–13.162, P=0.078; and OR =16.579, 95% CI: 2.586–106.287, P=0.012, respectively). Further, we investigated the preoperative predicted factors for reintubation. Only the preoperative ECMO remained a significant predictor of re-intubation (OR =4.69, 95% CI: 1.56–15.286, P=0.012).

Conclusions

Preoperative independent sputum clearance, preoperative ECMO, older than 65-year-old, and double lung or heart-LTx were four independent risk factors for unsuccessful extubation. Moreover, preoperative ECMO was the only independent risk factor for reintubation.

Utilization of extracorporeal membrane oxygenation in DCD and DBD lung transplants: a 2-year single-center experience

Donation after circulatory death (DCD) has the potential to expand the lung donor pool. We aimed to assess whether DCD affected the need for perioperative extracorporeal membrane oxygenation (ECMO) and perioperative outcomes in lung transplantation (LTx) as compared to donation after brain death (DBD). All consecutive LTxs performed between April 2017 and March 2019 at our tertiary center were analyzed. Donor and recipient preoperative characteristics, utilization of ECMO, and perioperative clinical outcomes were compared between DCD and DBD LTx. Multivariate models (frequentist and Bayes) were fitted to evaluate an independent effect of DCD on the intra- and postoperative need for ECMO. Out of 105 enrolled patients, 25 (23.8%) were DCD LTx. Donors' and preoperative recipients' characteristics were comparable between the groups. Intraoperatively, mechanical circulatory support (MCS) was more common in DCD LTx (56.0% vs. 36.2%), but the adjusted difference was minor (RR = 1.16, 95% CI 0.64-2.12; P = 0.613). MCS duration, and first and second lung ischemia time were longer in the DCD group. Postoperatively, DCD recipients more commonly required ECMO (32.0% vs. 7.5%) and the difference remained considerable after adjustment for the pre- and intraoperative covariates: RR = 4.11 (95% CI 0.95-17.7), P = 0.058, Bayes RR = 4.15 (95% CrI 1.28-13.0). Sensitivity analyses (two DCD-DBD matching procedures) supported a higher risk of postoperative ECMO need in DCD patients. Incidence of delayed chest closure, postoperative chest drainage, and renal replacement therapy was higher in the DCD group. Early postoperative outcomes after DCD LTx appeared generally comparable to those after DBD LTx. DCD was associated with a higher need for postoperative ECMO which could influence clinical outcomes. However, as the DCD group had a significantly higher use of EVLP with more common ECMO preoperatively, this might have contributed to worse outcomes in the DCD group.