Lung Transplant With Cardiopulmonary Bypass: Impact of Blood Transfusion on Rejection, Function, and Late Mortality

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

BACKGROUND

Lung 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).

METHODS

Adult 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.

RESULTS

A 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).

CONCLUSION

These 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.

Impact of anticoagulation intensity on blood transfusion for venoarterial extracorporeal membrane oxygenation during lung transplantation

Venoarterial extracorporeal membrane oxygenation is increasingly used for mechanical circulatory support during lung transplant. Optimal intensity of intraoperative anticoagulation would be expected to mitigate thromboembolism without increasing bleeding and blood product transfusions. Yet, the optimal intensity of intraoperative anticoagulation is unknown. We performed a retrospective cohort study of 163 patients who received a bilateral lung transplant at a single center. We categorized the intensity of anticoagulation into 4 groups (very low to high) based on the bolus dose of unfractionated heparin given during lung transplant and compared the rates of intraoperative blood transfusions and the occurrence of thromboembolism between groups. When compared to the very low-intensity group, each higher intensity group was associated with higher red blood cell, fresh frozen plasma, and platelet transfusions. The occurrence of thromboembolism was similar across groups. These preliminary data suggest that lower intensity anticoagulation may reduce the rate of intraoperative blood transfusions, although further study is needed.

Examining Bleeding Risk, Transfusion-related Complications, and Strategies to Reduce Transfusions in Lung Transplantation

Blood product transfusions for bleeding management in lung transplantation affect recipient outcomes. Interventions are needed to reduce perioperative bleeding risk and optimize outcomes.

Intraoperative Red Blood Cell Transfusion and Primary Graft Dysfunction After Lung Transplantation

BACKGROUND

In this international, multicenter study of patients undergoing lung transplantation (LT), we explored the association between the amount of intraoperative packed red blood cell (PRBC) transfusion and occurrence of primary graft dysfunction (PGD) and associated outcomes.

METHODS

The Extracorporeal Life Support in LT Registry includes data on LT recipients from 9 high-volume (>40 transplants/y) transplant centers (2 from Europe, 7 from the United States). Adult patients who underwent bilateral orthotopic lung transplant from January 2016 to January 2020 were included. The primary outcome of interest was the occurrence of grade 3 PGD in the first 72 h after LT.

RESULTS

We included 729 patients who underwent bilateral orthotopic lung transplant between January 2016 and November 2020. LT recipient population tertiles based on the amount of intraoperative PRBC transfusion (0, 1-4, and >4 units) were significantly different in terms of diagnosis, age, gender, body mass index, mean pulmonary artery pressure, lung allocation score, hemoglobin, prior chest surgery, preoperative hospitalization, and extracorporeal membrane oxygenation requirement. Inverse probability treatment weighting logistic regression showed that intraoperative PRBC transfusion of >4 units was significantly ( P  < 0.001) associated with grade 3 PGD within 72 h (odds ratio [95% confidence interval], 2.2 [1.6-3.1]). Inverse probability treatment weighting analysis excluding patients with extracorporeal membrane oxygenation support produced similar findings (odds ratio [95% confidence interval], 2.4 [1.7-3.4], P  < 0.001).

CONCLUSIONS

In this multicenter, international registry study of LT patients, intraoperative transfusion of >4 units of PRBCs was associated with an increased risk of grade 3 PGD within 72 h. Efforts to improve post-LT outcomes should include perioperative blood conservation measures.

Utilization of machine learning to model the effect of blood product transfusion on short-term lung transplant outcomes

The objective of this study was to identify the relationship between blood product transfusion and short-term morbidity and mortality following lung transplantation utilizing machine learning. Preoperative recipient characterstics, procedural variables, perioperative blood product transfusions, and donor charactersitics were included in the model. The primary composite outcome was occurrence on any of the following six endpoints: mortality during index hospitalization; primary graft dysfunction at 72 h post-transplant or the need for postoperative circulatory support; neurological complications (seizure, stroke, or major encephalopathy); perioperative acute coronary syndrome or cardiac arrest; and renal dysfunction requiring renal replacement therapy. The cohort included 369 patients, with the composite outcome occurring in 125 cases (33.9%). Elastic net regression analysis identified 11 significant predictors of composite morbidity: higher packed red blood cell, platelet, cryoprecipitate and plasma volume from the critical period, preoperative functional dependence, any preoperative blood transfusion, VV ECMO bridge to transplant, and antifibrinolytic therapy were associated with higher risk of morbidity. Preoperative steroids, taller height, and primary chest closure were protective against composite morbidity.

Effects of intraoperative fluid therapy on intensive care process, morbidity, and mortality after lung transplantation

Background

This study aims to evaluate the effect of intraoperative fluid therapy on intensive care process and first 90-day morbidity and mortality in patients undergoing lung transplantation.

Methods

Between March 2013 and December 2020, a total of 77 patients (64 males, 13 females; mean age: 47.6±13.0 years; range, 19 to 67 years) who underwent lung transplantation were retrospectively analyzed. The patients were divided into two groups according to the amount of fluid given intraoperatively: Group 1 (<15 mL/kg^-1/h^-1) and Group 2 (>15 mL/kg^-1/h^-1). Demographic, clinical, intra- and postoperative data of the patients were recorded.

Results

Less than 15 mL/kg-1/h-1 f luid w as a dministered t o 75.3% (n=58) of the patients (Group 1) and 24.7% (n=19) were administered more than 15 mL/kg-1/h-1 (Group 2). In t erms of native disease, the rate of diagnosis of chronic obstructive pulmonary disease and idiopathic pulmonary fibrosis was higher in Group 1, and the rate of other diagnoses was higher in Group 2 (p<0.01). The ratio of women in Group 2 was higher (p<0.05), while the body mass index values were significantly lower in this group (p<0.01). The erythrocyte, fresh frozen plasma, platelet, crystalloid and total fluid given in Group 2 were significantly higher (p<0.001). Inotropic/vasopressor agent use rates and extracorporeal membrane oxygenation requirement were significantly higher in Group 2 (p<0.01). Primary graft dysfunction, gastrointestinal complications, and mortality rates were also significantly higher in Group 2 (p<0.05).

Conclusion

The increased intraoperative fluid volume in lung transplantation is associated with primary graft dysfunction, gastrointestinal complications, and mortality rates.

New Aspects of Lung Transplantation: A Narrative Overview Covering Important Aspects of Perioperative Management

The management of lung transplant patients has continued to evolve in recent years. The year 2021 was marked by the publication of the International Consensus Recommendations for Anesthetic and Intensive Care Management of Lung Transplantation. There have been major changes in lung transplant programs over the last few years. This review will summarize the knowledge in anesthesia management of lung transplantation with the most recent data. It will highlight the following aspects which concern anesthesiologists more specifically: (1) impact of COVID-19, (2) future of transplantation for cystic fibrosis patients, (3) hemostasis management, (4) extracorporeal membrane oxygenation management, (5) early prediction of primary graft dysfunction, and (6) pain management.

Blood product transfusion and lung transplant outcomes: A systematic review

The perioperative transfusion of blood products has long been linked to development of acute lung injury and associated with mortality across both medical and surgical patient populations.^1,2 The need for blood product transfusion during and after lung transplantation is common and, in many instances, unavoidable. However, this practice may potentially be modifiable.³ In this systematic review, we explore and summarize what is known regarding the impact of blood product transfusion on outcomes following lung transplantation, highlighting the most recent work in this area. Overall, the majority of the literature consists of single center retrospective analyses or the work of multicenter working groups referencing the same database. In the end, there are a number of remaining questions regarding blood product transfusion and their downstream effects on graft function and survival.

Extracorporeal life support during lung transplantation

Lung transplantation surgeries are performed without extracorporeal life support (ECLS) by using an off-pump technique; however, in cases of hypoxemia or hemodynamic instability, intraoperative ECLS may be required. Cardiopulmonary bypass (CPB) has traditionally been the standard practice for ECLS but has been associated with an increased risk of bleeding in the perioperative period, increased transfusion requirements, prolonged postoperative intubation, and possibly primary graft dysfunction. More recently, because of the flexibility of using extracorporeal membrane oxygenation (ECMO) in bridging to transplantation and during postoperative recovery, its use has increased. CPB and ECMO each has advantages and disadvantages; however, because comparisons of CPB and ECMO have been limited to small retrospective observational and single-institution studies, more research is required to determine the superiority of one modality. In this review, we critically examine the pros and cons of performing lung transplantation surgery off-pump or by using the ECLS modalities of ECMO and CPB support during lung transplantation surgery.

Blood transfusions may adversely affect survival outcomes of patients with lung cancer: a systematic review and meta-analysis

Background

Despite common use in clinical practice, the impact of blood transfusions on prognosis among patients with lung cancer remains unclear. The purpose of the current study is to perform an updated systematic review and meta-analysis to evaluate the influence of blood transfusions on survival outcomes of lung cancer patients.

Methods

We searched PubMed, Embase, Cochrane Library, and Ovid MEDLINE for publications illustrating the association between blood transfusions and prognosis among people with lung cancer from inception to November 2019. Overall survival (OS) and disease-free survival (DFS) were the outcomes of interest. Pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were computed using the random-effects model. Study heterogeneity was evaluated with the I² test. Publication bias was explored via funnel plot and trim-and-fill analyses.

Results

We included 23 cohort studies with 12,175 patients (3,027 cases and 9,148 controls) for meta-analysis. Among these records, 22 studies investigated the effect of perioperative transfusions, while one examined that of transfusions during chemotherapy. Two studies suggested the possible dose-dependent effect in accordance with the number of transfused units. In pooled analyses, blood transfusions deleteriously influenced both OS (HR=1.35, 95% CI: 1.14–1.61, P<0.001, I²=0%) and DFS (HR=1.46, 95% CI: 1.15–1.86, P=0.001, I²=0%) of people with lung cancer. No evidence of significant publication bias was detected in funnel plot and trim-and-fill analyses (OS: HR=1.26, 95% CI: 1.07–1.49, P=0.006; DFS: HR=1.35, 95% CI: 1.08–1.69, P=0.008).

Conclusions

Blood transfusions were associated with decreased survival of patients with lung cancer.

Initial Postoperative Hemoglobin Values Are Independently Associated With One-Year Mortality in Patients Undergoing Double-Lung Transplantation Requiring Intraoperative Transfusion

OBJECTIVE

To evaluate the association of postoperative hemoglobin values and mortality in patients undergoing double- lung transplantation with intraoperative transfusion.

DESIGN

Retrospective cohort study.

SETTING

University hospital.

PARTICIPANTS

Adult patients who underwent double-lung transplantation at the authors' institution, with intraoperative transfusion of packed red blood cells between 2009 and 2015.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Intraoperative transfusion requirements and general characteristics of 554 patients were collected. A generalized additive model, controlling for postoperative hemoglobin levels, number of transfused units of packed red blood cells, perioperative change in hemoglobin levels, disease leading to lung transplantation, and postoperative extracorporeal membrane oxygenation, was created to predict one-year mortality. A postoperative hemoglobin level of 11.3 g/dL was calculated as an optimal cutoff point. The patients were stratified according to this level. The end -point was all-cause one-year mortality after double-lung transplantation, assessed using the Kaplan-Meier analysis with log-rank test. All-cause mortality of the 554 patients was 17%. Postoperatively, 171 patients (31%) were categorized as being below the cutoff point. Improved survival was observed in the group with higher postoperative hemoglobin values (p = 0.002).

CONCLUSION

Lower postoperative hemoglobin levels in double-lung transplantation recipients were associated with increased mortality during the first year after surgery. Confirmation of these findings in additional investigations could alter patient blood management for double-lung transplantation.

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.

Anesthetic management of lung transplantation: Results from a multicenter, cross-sectional survey by the society for advancement of transplant anesthesia

BACKGROUND

Current protocols for the perioperative care of lung transplant (LTX) recipients lack rigorous evidence and are often empiric, based upon institutional preferences. We surveyed LTX anesthesiologists to determine the most common practices.

METHODS

We developed a survey of 40 questions regarding perioperative care of LTX recipients using Qualtrics software. The survey was sent out to members of the Society of Cardiovascular Anesthesiologists performing LTX at geographically diverse sites to facilitate data collection for as many practices as possible.

RESULTS

The responses were center-weighed (127 responses, 85% from academic settings). The clamshell approach was commonly used (70%). Cardiopulmonary bypass was preferred by 56%, ex vivo lung perfusion utilized by 43%, and 49.4% indicated they use lungs from donation after circulatory determination of death. Most (69%) used oximetric pulmonary artery catheters, 60% used tissue oximetry, and 89.3% utilized transesophageal echocardiography. Inhaled nitric oxide was preferred by 48%, restrictive fluid management by 48%, and systemic analgesia advocated by 49% of participants. Inspired oxygen concentration <30% was applied to the new lung on reperfusion by 28% of the respondents.

CONCLUSION

Variations in healthcare delivery and utilization for LTX recipients indicate gaps in knowledge and potential opportunities to improve the quality of care.

Perioperative Management of Bleeding and Transfusion for Lung Transplantation

Perioperative allogeneic blood product transfusion is common in lung transplantation and has various implications on the short- and long-term outcomes of lung recipients. This review summarizes the effect of transfusion on outcomes including primary graft dysfunction, chronic lung allograft dysfunction, and all-cause mortality. We outline known risk factors for increased transfusion requirement in lung transplantation and present current evidence regarding the effect of hemostatic agents including antifibrinolytics, recombinant factor VII, and prothrombin complex concentrates. Finally, we highlight the roles of point-of-care coagulation testing and goal-directed transfusion strategies in reducing transfusion requirements in lung transplantation.

Incidence of Massive Transfusion and Overall Transfusion Requirements During Lung Transplantation Over a 25-Year Period

OBJECTIVE

To establish the incidence of massive transfusion and overall transfusion requirements during lung transplantation, changes over time, and association with outcome in relation to patient complexity.

DESIGN

Retrospective cohort study.

SETTING

University hospital.

PARTICIPANTS

All 514 adult patients who underwent transplantation from 1990 until 2015.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Patient records and transfusion data, divided into 5-year intervals, were analyzed. The incidence of massive transfusion (>10 units of red blood cells [RBCs] in 24 h) was 27% and did not change over time, whereas the median (interquartile range) transfusion requirement in the whole cohort decreased from 8 (5-12) to 3 (0-10) RBCs (p < 0.001). In patients transplanted from the intensive care unit, the incidence of massive transfusion increased over time from 25% to 54% (p = 0.04) and median transfusion requirements from 4.5 (3-8.5) units to 14.5 (5-26) units of RBCs (p = 0.03). Multivariable analysis showed that circulatory support, pulmonary hypertension, re-transplantation, cystic fibrosis, Eisenmenger syndrome, bilateral transplantation, and low body mass index were associated with massive transfusion. Patients with massive transfusion had more primary graft dysfunction grade III at 0, 24, 48, and 72 hours (p < 0.001), higher 30-day mortality (13% v 4%; p < 0.001), and lower 5-year survival (hazard ratio 3.67 [95% confidence interval 1.72-7.85]; p < 0.001).

CONCLUSION

The incidence of massive transfusion did not change over time, whereas transfusion requirements in the whole cohort decreased. In patients transplanted from the intensive care unit, massive transfusion and transfusion requirements increased. Massive transfusion was associated with poor outcome.

Noteworthy Literature Published in 2016 for Thoracic Organ Transplantation Anesthesiologists

This article is first in the series to review the published literature on perioperative issues in patients undergoing thoracic solid organ transplantations. We present recent literature from 2016 on preoperative considerations, organ preservation, intraoperative anesthesia management, surgical techniques, postoperative complications, and the impact of perioperative management on short- and long-term outcomes that are pertinent to thoracic transplantation anesthesiologists.