Lung transplantation: candidate selection and timing of transplant

Extracorporeal photopheresis for the prevention of rejection after lung transplantation: a prospective randomised controlled trial

BACKGROUND

Lung transplant recipients have the worst long-term outcomes of all solid organs due to acute rejection and chronic lung allograft dysfunction (CLAD). Our objective was to investigate the efficacy of extracorporeal photopheresis (ECP) as a prophylactic treatment to prevent acute cellular rejection (ACR), cytomegalovirus (CMV) infections and reduce the risk of CLAD.

METHODS

This was a single-centre prospective randomised controlled trial conducted at the Medical University of Vienna (Vienna, Austria) between 2018 and 2020. It included 31 COPD recipients per group. The treatment group underwent ECP in addition to a standard triple-drug immunosuppression protocol after lung transplantation. The control group received standard triple-drug immunosuppressive therapy. The primary outcome was a composite outcome defined as incidence of high-grade ACR, CMV infection or CLAD within 24 months after lung transplantation.

RESULTS

In the control group, 19 patients (61.3%) achieved the primary combined end-point compared with only six patients (19.4%) in the treatment group (p<0.001). Freedom from high-grade ACR was significantly greater in the ECP group (p=0.045). Cumulative A scores were significantly lower in the ECP group than in the control group at 3 months (0.18±0.44 versus 0.56±0.94; p<0.05) and at 12 months (0.25±0.48 versus 1.0±1.45; p=0.002). The rate of infections was lower in the ECP group with five cases and 67 cumulative hospital days compared with 22 cases and 309 days in the control group (p=0.002). Freedom from CLAD at 3 years was significantly greater in the ECP group (p=0.015).

CONCLUSION

Adding ECP to standard triple immunosuppression resulted in a significant reduction of the number of ACR episodes and significantly lower incidence of CLAD.

Venopulmonary extracorporeal membrane oxygenation for right ventricular support as a bridge to lung transplantation: A narrative review

This review evaluates the effectiveness of veno-pulmonary support with an oxygenator using extracorporeal membrane oxygenation as a bridge to lung transplantation strategy in patients undergoing veno-venous extracorporeal membrane oxygenation while awaiting lung transplantation. Examining indications, contraindications, and clinical outcomes, the study highlights potential benefits, drawing insights from successful cases in South Korea and the United States. Despite limited sample sizes, veno-pulmonary support with an oxygenator using extracorporeal membrane oxygenation emerges as a promising approach for further investigation in lung transplantation support. The review emphasizes its role in improving hemodynamic status, preventing complications during extended waiting periods, and presenting a cost-effective alternative to traditional methods, especially in developing countries. While in-hospital mortality rates range from 0% to 10%, comparable to other approaches, cautious optimism surrounds veno-pulmonary support with an oxygenator using extracorporeal membrane oxygenation, urging expanded research to solidify its standing in enhancing patient outcomes, reducing costs, and promoting transplant success.

Outcomes associated with prolonged ECMO in COVID-19 associated ARDS: A single center experience

PURPOSE OF STUDY

The COVID-19 pandemic has led to a significant increase in the use of veno-venous extracorporeal membrane oxygenation (V-V ECMO) as a bridge to transplantation versus recovery. Unlike other etiologies of acute respiratory distress syndrome (ARDS), utilization of V-V ECMO in COVID-19 has been associated with longer duration of ECMO support requirements. Our team sought to evaluate outcomes associated with prolonged duration of ECMO support in this patient population.

METHODS

Single-center retrospective review of patients who were placed on ECMO due to COVID-19 associated ARDS. Specifically examining outcomes-transplant free survival, mortality and discharge rates-of patients requiring V-V ECMO support for greater than 50 days.

RESULTS

The median age of the cohort was 48 years and 13 patients (72%) were males. The median duration of ECMO support was 84 days (IQR 55-106). 11 patients (61%) had right ventricular dysfunction and 13 patients (72%) had pneumothoraces. There was a 33% percent (n = 6) mortality rate within cohort. One patient continues to require ECMO support at time of abstract submission. 11 patients (61%) patients were discharged, of which 3 patients required a lung transplant.

SUMMARY

Prolonged V-V ECMO can be associated with comparable outcomes to conventional V-V ECMO runs that are relatively shorter in duration. With availability of device and staffing, prolonged ECMO runs can potentially be justified in a highly selected patient population.

Uptake and 1-year outcomes of lung transplantation for COVID-19

OBJECTIVE

End-stage lung disease from severe COVID-19 infection is an increasingly common indication for lung transplantation (LT), but there are limited data on outcomes. We evaluated 1-year COVID-19 LT outcomes.

METHODS

We identified all adult US LT recipients January 2020 to October 2022 in the Scientific Registry for Transplant Recipients, using diagnosis codes to identify recipients transplanted for COVID-19. We used multivariable regression to compare in-hospital acute rejection, prolonged ventilator support, tracheostomy, dialysis, and 1-year mortality between COVID-19 and non-COVID-19 recipients, adjusting for donor, recipient, and transplant characteristics.

RESULTS

LT for COVID-19 increased from 0.8% to 10.7% of total LT volume during 2020 to 2021. The number of centers performing LT for COVID-19 increased from 12 to 50. Recipients transplanted for COVID-19 were younger; were more likely to be male and Hispanic; were more likely to be on a ventilator, extracorporeal membrane oxygenation support, and dialysis pre-LT; were more likely to receive bilateral LT; and had higher lung allocation score and shorter waitlist time than other recipients (all P values < .001). COVID-19 LT had higher risk of prolonged ventilator support (adjusted odds ratio, 2.28; P < .001), tracheostomy (adjusted odds ratio 5.3; P < .001), and longer length of stay (median, 27 vs 19 days; P < .001). Risk of in-hospital acute rejection (adjusted odds ratio, 0.99; P = .95) and 1-year mortality (adjusted hazard ratio, 0.73; P = .12) were similar for COVID-19 LTs and LTs for other indications, even accounting for center-level differences.

CONCLUSIONS

COVID-19 LT is associated with higher risk of immediate postoperative complications but similar risk of 1-year mortality despite more severe pre-LT illness. These encouraging results support the ongoing use of LT for COVID-19-related lung disease.

Overly Selective Offer Acceptance is Associated With High Waitlist Mortality for the Most Ill Lung Transplant Candidates

The demand for organs for lung transplantation (LTx) continues to outweigh supply. However, nearly 75% of donor lungs are never transplanted. LTx offer acceptance practices and the effects on waitlist/post-transplant outcomes by candidate clinical acuity are understudied. UNOS was used to identify all LTx candidates, donors, and offers from 2005 to 2019. Candidates were grouped by Lung Allocation Score (LAS; applicable post-2005, ages ≥12 years): LAS<40, 40-60, 61-80, and >80. Offer acceptance patterns, waitlist death/decompensation, and post-transplant survival (PTS) were compared. "Acceptable organ offers" were those from donors whose organs were accepted for transplantation. Approximately 3 million offers to 34,531 candidates were reviewed. Median waitlist durations were: 9 days-(LAS>80), 17 days-(LAS 61-80), 42 days-(LAS 40-60), 125 days-(LAS<40) (P < 0.001 between all). Per waitlist-day, offer rates were: total offers - 0.8/day-(LAS>80), 0.7/day-(LAS 61-80), 0.6/day-(LAS 40-60), 0.4/day-(LAS<40); acceptable offers - 0.34/day-(LAS>80), 0.32/day-(LAS 61-80), 0.24/day-(LAS 40-60), 0.15/day-(LAS<40) (both P < 0.001 between all LAS). Among patients who experienced waitlist mortality/decompensation, ≥1 acceptable offer was declined in 92% (3939/4270) of patients - 78% for LAS >80, 88% for LAS 61-80, 93% for LAS 40-60, and 96% for LAS <40. Thirty-day waitlist mortality/decompensation rates were: 46%-(LAS>80), 24%-(LAS 61-80), 5%-(LAS 40-60), <1%-(LAS<40) (P < 0.001 between all). PTS was equivalent between patients for whom the first/second offer vs later offers were accepted (all LAS P > 0.4). The first offers that LTx candidates receive (including acceptable organs) are declined for nearly all candidates. Healthier candidates can afford offer selectivity but more ill patients (LAS>60) cannot, experiencing exceedingly high 30-day waitlist mortality.