Impact of Deceased Donor Management on Donor Heart Use and Recipient Graft Survival

Active Donor Management Goals in Serial Donors After Brain Death

OBJECTIVES

Management of potential organ donors is crucial in the donation process, considering that hemodynamic instability is quite common.

MATERIALS AND METHODS

In the this single-center retrospective observational study, we analyzed 87 utilized brain death donors consecutively admitted to our intensive care unit from January 1, 2019, to December 31, 2022. We assessed the achievement of donor management goals during the observation period, and we also evaluated whether the achieve-ment of donor goals differed between younger and older donors (arbitrary age cutoff of 65 years).

RESULTS

In our series, mean age of donors was 67 ± 18 y, and organ-per-donor ratio was 2.3. The number of donor goals significantly increased during the 6-hour observation period (P < .001) and all donor goals were achieved in most donors (84/87) at the end of the observation period with no changes in the use and dose of vasoactive drugs. With respect to age, the number of donor goals was significantly higher in older donors at first evaluation, but goals significantly increased in both age subgroups of donors at the end of the 6-hour observation period.

CONCLUSIONS

Our data strongly suggested that a strict hemodynamic monitoring schedule allows the achievement of donor goals both in older and in younger brain death donors. We confirmed our previous findings that hemodynamic management in brain death donors is influenced by age. A strict hemodynamic monitoring schedule of brain death donors is useful to consistently achieve donor goals.

Intravenous Levothyroxine for Unstable Brain-Dead Heart Donors

BACKGROUND

Hemodynamic instability and myocardial dysfunction are major factors preventing the transplantation of hearts from organ donors after brain death. Intravenous levothyroxine is widely used in donor care, on the basis of observational data suggesting that more organs may be transplanted from donors who receive hormonal supplementation.

METHODS

In this trial involving 15 organ-procurement organizations in the United States, we randomly assigned hemodynamically unstable potential heart donors within 24 hours after declaration of death according to neurologic criteria to open-label infusion of intravenous levothyroxine (30 μg per hour for a minimum of 12 hours) or saline placebo. The primary outcome was transplantation of the donor heart; graft survival at 30 days after transplantation was a prespecified recipient safety outcome. Secondary outcomes included weaning from vasopressor therapy, donor ejection fraction, and number of organs transplanted per donor.

RESULTS

Of the 852 brain-dead donors who underwent randomization, 838 were included in the primary analysis: 419 in the levothyroxine group and 419 in the saline group. Hearts were transplanted from 230 donors (54.9%) in the levothyroxine group and 223 (53.2%) in the saline group (adjusted risk ratio, 1.01; 95% confidence interval [CI], 0.97 to 1.07; P = 0.57). Graft survival at 30 days occurred in 224 hearts (97.4%) transplanted from donors assigned to receive levothyroxine and 213 hearts (95.5%) transplanted from donors assigned to receive saline (difference, 1.9 percentage points; 95% CI, -2.3 to 6.0; P<0.001 for noninferiority at a margin of 6 percentage points). There were no substantial between-group differences in weaning from vasopressor therapy, ejection fraction on echocardiography, or organs transplanted per donor, but more cases of severe hypertension and tachycardia occurred in the levothyroxine group than in the saline group.

CONCLUSIONS

In hemodynamically unstable brain-dead potential heart donors, intravenous levothyroxine infusion did not result in significantly more hearts being transplanted than saline infusion. (Funded by Mid-America Transplant and others; ClinicalTrials.gov number, NCT04415658.).

Donor hyperoxia is a novel risk factor for severe cardiac primary graft dysfunction

BACKGROUND

Primary graft dysfunction (PGD) is a major cause of early mortality following heart transplant (HT). Donor risk factors for the development of PGD are incompletely characterized. Donor management goals (DMG) are predefined critical care endpoints used to optimize donors. We evaluated the relationship between DMGs as well as non-DMG parameters, and the development of PGD after HT.

METHODS

A cohort of HT recipients from 2 transplant centers between 1/1/12 and 12/31/19 was linked to their respective donors in the United Network for Organ Sharing (UNOS) DMG Registry (n = 1,079). PGD was defined according to modified ISHLT criteria. Variables were subject to univariate and multivariable multinomial modeling with development of mild/moderate or severe PGD as the outcome variable. A second multicenter cohort of 4,010 donors from the DMG Registry was used for validation.

RESULTS

Mild/moderate and severe PGD occurred in 15% and 6% of the cohort. Multivariable modeling revealed 6 variables independently associated with mild/moderate and 6 associated with severe PGD, respectively. Recipient use of amiodarone plus beta-blocker, recipient mechanical circulatory support, donor age, donor fraction of inspired oxygen (FiO₂), and donor creatinine increased risk whereas predicted heart mass ratio decreased risk of severe PGD. We found that donor age and FiO₂ ≥ 40% were associated with an increased risk of death within 90 days post-transplant in a multicenter cohort.

CONCLUSIONS

Donor hyperoxia at heart recovery is a novel risk factor for severe primary graft dysfunction and early recipient death. These results suggest that excessive oxygen supplementation should be minimized during donor management.

Differential donor management of pediatric vs adult organ donors and potential impact on pediatric lung transplantation

BACKGROUND

Despite clinical progress over time, a shortage of suitable donor organs continues to limit solid organ transplantation around the world. Lungs are the organs most likely to be assessed as unsuitable during donor management among all transplantable organs. Although the number of lung transplants performed in children is limited, death on the wait list remains a barrier to transplant success for many potential transplant candidates. Optimizing organ donor management can yield additional organs for transplant candidates.

METHODOLOGY

We accessed the Donor Management Goal (DMG) Registry to evaluate the efficiency and efficacy of donor management in the procurement of lungs for transplantation. Further, we stratified donors by age and compared pediatric age cohorts to adult cohorts with respect to attainment of donor management target goals and successful pathway to transplantation. We utilized recipient data from the Organ Procurement Transplantation Network (OPTN) to put this data into context. The DMG bundle consists of nine physiologic parameters chosen as end-points guiding donor management for potential organ donors. The number of parameters fulfilled has been regarded as an indication of efficacy of donor management.

RESULTS

We noted a markedly lower number of organ donors in the pediatric age group compared to adults. On the other hand, the number of donors greatly exceeds the number of infants, children and adolescents who undergo lung transplantation. Organs transplanted per donor peaks in the adolescent age group. At initial donor referral, DMG bundle attainment is lower in all age groups and improves during donor management. With respect to oxygenation, there is less overall improvement in younger donors compared to older donors during donor management. When donors who yield lungs for transplantation are compared to those whose lungs were not transplanted, oxygenation improved more substantially during donor management. Furthermore, improved oxygenation correlated with the total number of organs transplanted per donor.

CONCLUSIONS

In the face of continued wait list mortality on the pediatric lung transplant wait list, the number of young donors may not be a limiting factor. We believe that this dataset provides evidence that management of young pediatric donors is not as consistent or efficient as the management of older donors, potentially limiting the number of life-saving organs for pediatric lung transplant candidates. Across all ages, optimizing donor lung management may increase the potential to transplant multiple other organs.

A multicenter randomized placebo-controlled trial of intravenous thyroxine for heart-eligible brain-dead organ donors

Background

Brain death frequently induces hemodynamic instability and cardiac stunning. Impairments in cardiac performance are major contributors to hearts from otherwise eligible organ donors not being transplanted. Deficiencies in pituitary hormones (including thyroid-stimulating hormone) may contribute to hemodynamic instability, and replacement of thyroid hormone has been proposed as a means of improving stability and increasing hearts available for transplantation. Intravenous thyroxine is commonly used in donor management. However, small controlled trials have not been able to demonstrate efficacy.

Methods

This multicenter study will involve organ procurement organizations (OPOs) across the country. A total of 800 heart-eligible brain-dead organ donors who require vasopressor support will be randomly assigned to intravenous thyroxine for at least 12 h or saline placebo. The primary study hypotheses are that thyroxine treatment will result in a higher proportion of hearts transplanted and that these hearts will have non-inferior function to hearts not treated with thyroxine. Additional outcome measures are the time to achieve hemodynamic stability (weaning off vasopressors) and improvement in cardiac ejection fraction on echocardiography.

Discussion

This will be the largest randomized controlled study to evaluate the efficacy of thyroid hormone treatment in organ donor management. By collaborating across multiple OPOs, it will be able to enroll an adequate number of donors and be powered to definitively answer the critical question of whether intravenous thyroxine treatment increases hearts transplanted and/or provides hemodynamic benefits for donor management.

Trial registration

ClinicalTrials.govNCT04415658. Registered on June 4, 2020

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05797-2.

Organ donor management goals and delayed graft function in adult kidney transplant recipients

BACKGROUND

Delayed graft function (DGF) after kidney transplantation is a common occurrence and correlates with poor graft and patient outcomes. Donor characteristics and care are known to impact DGF. We attempted to show the relationship between achievement of specific donor management goals (DMG) and DGF.

METHODS

This is a retrospective case-control study using data from 14 046 adult kidney donations after brain death from hospitals in 18 organ procurement organizations (OPOs) which were transplanted to adult recipients between 2012 and 2018. Data on DMG compliance and donor, recipient, and ischemia-related factors were used to create multivariable logistic regression models.

RESULTS

The overall rate of DGF was 29.4%. Meeting DMGs for urine output and vasopressor use were associated with decreased risk of DGF. Sensitivity analyses performed with different imputation methods, omitting recipient factors, and analyzing multiple time points yielded largely consistent results.

CONCLUSIONS

The development of DMGs continues to show promise in improving outcomes in the kidney transplant recipient population. Studies have already shown increased kidney utilization in smaller cohorts, as well as other organs, and shown decreased rates of DGF. Additional research and analysis are required to assess interactions between meeting DMGs and correlation versus causality in DMGs and DGF.