Improving donor management and transplantation success: more research is needed

Evidence-Based Checklist to Delay Cardiac Arrest in Brain-Dead Potential Organ Donors: The DONORS Cluster Randomized Clinical Trial

Importance

The effectiveness of goal-directed care to reduce loss of brain-dead potential donors to cardiac arrest is unclear.

Objective

To evaluate the effectiveness of an evidence-based, goal-directed checklist in the clinical management of brain-dead potential donors in the intensive care unit (ICU).

Design, Setting, and Participants

The Donation Network to Optimize Organ Recovery Study (DONORS) was an open-label, parallel-group cluster randomized clinical trial in Brazil. Enrollment and follow-up were conducted from June 20, 2017, to November 30, 2019. Hospital ICUs that reported 10 or more brain deaths in the previous 2 years were included. Consecutive brain-dead potential donors in the ICU aged 14 to 90 years with a condition consistent with brain death after the first clinical examination were enrolled. Participants were randomized to either the intervention group or the control group. The intention-to-treat data analysis was conducted from June 15 to August 30, 2020.

Interventions

Hospital staff in the intervention group were instructed to administer to brain-dead potential donors in the intervention group an evidence-based checklist with 13 clinical goals and 14 corresponding actions to guide care, every 6 hours, from study enrollment to organ retrieval. The control group provided or received usual care.

Main Outcomes and Measures

The primary outcome was loss of brain-dead potential donors to cardiac arrest at the individual level. A prespecified sensitivity analysis assessed the effect of adherence to the checklist in the intervention group.

Results

Among the 1771 brain-dead potential donors screened in 63 hospitals, 1535 were included. These patients included 673 males (59.2%) and had a median (IQR) age of 51 (36.3-62.0) years. The main cause of brain injury was stroke (877 [57.1%]), followed by trauma (485 [31.6%]). Of the 63 hospitals, 31 (49.2%) were assigned to the intervention group (743 [48.4%] brain-dead potential donors) and 32 (50.8%) to the control group (792 [51.6%] brain-dead potential donors). Seventy potential donors (9.4%) at intervention hospitals and 117 (14.8%) at control hospitals met the primary outcome (risk ratio [RR], 0.70; 95% CI, 0.46-1.08; P = .11). The primary outcome rate was lower in those with adherence higher than 79.0% than in the control group (5.3% vs 14.8%; RR, 0.41; 95% CI, 0.22-0.78; P = .006).

Conclusions and Relevance

This cluster randomized clinical trial was inconclusive in determining whether the overall use of an evidence-based, goal-directed checklist reduced brain-dead potential donor loss to cardiac arrest. The findings suggest that use of such a checklist has limited effectiveness without adherence to the actions recommended in this checklist.

Trial Registration

ClinicalTrials.gov Identifier: NCT03179020.

Histological, Laboratorial, and Clinical Benefits of an Optimized Maintenance Strategy of a Potential Organ Donor-A Rabbit Experimental Model

INTRODUCTION

Most transplanted organs are obtained from brain-dead donors. Inflammation results in a higher rate of rejection. Objectives: The objective of this animal model of brain death (BD) was to evaluate the effect of the progressive institution of volume expansion, norepinephrine, and combined hormone therapy on clinical, laboratory, and histological aspects. Methods: Twenty rabbits were divided: A (control), B (induction of BD + infusion of crystalloid), C (BD + infusion of crystalloid and noradrenaline (NA)), and D (BD + infusion of crystalloid + vasopressin + levothyroxine + methylprednisolone + NA). The animals were monitored for four hours with consecutives analysis of vital signs and blood samples. The organs were evaluated by a pathologist. Results: In Group D, we observed fewer number and lesser volume of infusions (p = 0.032/0.014) when compared with groups B and C. Mean arterial pressure levels were higher in group D when compared with group B (p = 0.008). Group D had better glycemic control when compared with group C (p = 0.016). Sodium values were elevated in group B in relation to groups C and D (p = 0.021). In Group D, the organ perfusion was better. Conclusion: The optimized strategy of management of BD animals is associated with better hemodynamic, glycemic, and natremia control, besides reducing early signs of ischemia.

Predictors of 1-year mortality in adult lung transplant recipients: a systematic review and meta-analysis

BACKGROUND

Upon surviving the first year post-lung transplantation, recipients can expect a median survival of 8 years. Within the first year, graft failure and multi-organ failure (possibly secondary to graft failure) are common causes of mortality. To better understand the prognosis within the first year, we plan on conducting a systematic review and meta-analysis of observational studies addressing the association between the patient, donor, and transplant operative factors and graft loss 1-year post-lung transplant.

METHODS

We searched MEDLINE, Embase, Cochrane Database of Systematic Reviews, Cochrane Central Register, and PubMed supplemental for non-MEDLINE records for observational studies identifying independent risk factors for early mortality (1 year) in adult lung transplant recipients. We plan on including cohort studies and secondary analyses of randomized controlled trials studying adult lung transplant recipients undergoing their first lung transplant, without any simultaneous organ transplant. We will conduct a random-effects meta-analysis that pools the effect estimates from all eligible studies to obtain a summary estimate and confidence interval for all independent non-therapeutic factors identified in the primary studies.

DISCUSSION

The results from this study may inform future guidelines on the selection of candidates and donors for transplantation and predictive model development and inform the decision-making process that the physician and patient undertake together. Furthermore, through the conduction of this review, we can identify the limitations with the current best evidence, which will encourage the need for studies with a better methodology to reassess the predictors of mortality.

Peripheral tissue oxygenation and the number of organs transplanted per donor

Current donor management practices target macrohaemodynamic parameters, but it is unclear if this leads to improvements in microvascular perfusion and tissue oxygenation; the latter may have more impact on organ status. In a recent preclinical study we determined that brain death impaired tissue perfusion and oxygen utilisation in swine while pharmacologic correction of these deficits improved organ function and reduced markers of tissue injury. As a first step in translating the preclinical findings, we conducted a prospective observational study to determine if there was an association between peripheral tissue oxygenation (measured by near-infrared spectroscopy) in deceased by neurological criteria human donors and the number of organs transplanted. In 60 donors, the mean time-weighted average of tissue oxygenation was 87.5% (standard deviation, SD, 5.2%) and the average number of organs transplanted was 3.5 (SD 2); there was a positive linear relationship between these two parameters. A 5% rise in tissue oxygenation was associated with an increase of 0.47 organs transplanted (95% confidence intervals 0.16 to 0.78) after adjusting for age (<i>P</i>=0.004). No such correlations were observed for the macrohaemodynamic or macro-oxygenation parameters (including arterial blood oxygenation). The results of this clinical trial are consistent with our preclinical work and support the postulate that targeting the microvasculature to improve tissue perfusion and tissue oxygen delivery in human donors has the potential to increase the quantity of organs suitable for transplant.

Hamilton-DONATE: a city-wide pilot observational study of the ICU management of deceased organ donors

PURPOSE

Improving the medical care of deceased organ donors to increase transplant rates and improve allograft function requires an understanding of the current epidemiology and clinical practices of deceased donation within intensive care units (ICUs). Herein, we report the results of our investigation into the feasibility of a multicentre prospective cohort study addressing the afformentioned issues.

METHODS

We conducted a 12-month prospective observational cohort study in six ICUs and one coronary care unit in Hamilton, Canada. We included consecutive children and adults following consent for deceased organ donation (including neurologic determination of death [NDD] or donation after circulatory death [DCD]). Intensive care unit research staff recorded donor management data from hospital records, extending from one day prior to the consent for organ donation up to the time of organ retrieval. The provincial Organ Donation Organization (ODO) supplemented these data and, additionally, provided data on corresponding organ recipients. We identified, evaluated, and measured three potential obstacles to the feasibility of a national cohort study: obtaining authorization to implement the study with a waiver of research consent, accessibility of transplant recipient data, and the time required to complete very detailed case report forms (CRFs), with valuable lessons learned for implementation in future projects.

RESULTS

The local Research Ethics Board and the ODO Privacy Office both authorized the recording of donor and recipient study data with a waiver of research consent. Sixty-seven consecutive consented donors were included (31 NDD and 36 DCD donors); 50 of them provided 144 organs for transplantation to 141 recipients. We identified the age and sex of the recipients as well as the location and date of transplant for all organ recipients in Ontario; however, we obtained no recipient data for six organs transported outside of Ontario. Intensive care unit research staff estimated that future CRF completion will require five to seven hours per patient.

CONCLUSION

The Hamilton-DONATE pilot study supports the feasibility of a larger cohort study to describe the epidemiology and clinical practices related to deceased donor care in Canada.

TRIAL REGISTRATION

wwwclinicaltrials.gov (NCT02902783). Registered 16 September 2016.

Impact of graft preservation solutions for liver transplantation on early cytokine release and postoperative organ dysfunctions. A pilot study

INTRODUCTION

During liver transplantation, graft ischemia-reperfusion injury leads to a systemic inflammatory response producing postoperative organ dysfunctions. The aim of this observational and prospective study was to compare the impact of Solution de conservation des organes et tissus (SCOT) 15 and University of Wisconsin (UW) preservation solutions on early cytokine release, postreperfusion syndrome and postoperative organ dysfunctions.

METHODS

Thirty-seven liver transplantations were included: 21 in UW Group and 16 in SCOT 15 group. Five cytokines were measured in systemic blood after anesthetic induction, 30minutes after unclamping portal vein and on postoperative day 1.

RESULTS

Following unclamping portal vein, cytokines were released in systemic circulation. Systemic cytokine concentrations were higher in UW than in SCOT 15 group: Interleukin-10, Interleukine-6. In SCOT 15 group, significant reduction of postreperfusion syndrome incidence and acute kidney injury were observed. Alanine and aspartate aminotransferase peak concentrations were higher in SCOT 15 group than in UW group. However, from postoperative day 1 to day 10, aminotransferase returned to normal values and did not differ between groups.

CONCLUSIONS

Compared to UW, SCOT 15 decreases systemic cytokine release resulting from graft ischemia-reperfusion injury and reduces incidence of postreperfusion syndrome and postoperative renal failure.

Canada-DONATE study protocol: a prospective national observational study of the medical management of deceased organ donors

INTRODUCTION

Research on the management of deceased organ donors aims to improve the number and quality of transplants and recipient outcomes. In Canada, this research is challenged by regionalisation of donation services within provinces and the geographical, clinical and administrative separation of donation from transplantation services. This study aims to build a national platform for future clinical trials in donor management. Objectives are to engage collaborators at donation hospitals and organ donation organisations (ODOs) across Canada, describe current practices, evaluate the effectiveness of donation-specific interventions and assess the feasibility of future clinical trials.

METHODS AND ANALYSIS

This ongoing prospective observational study of the medical management of deceased organ donors will enrol more than 650 consented potential donors from adult intensive care units at 33 hospital sites across Canada, each participating for 12 months. ODOs ensure enrolment of consecutive eligible participants. Research staff record detailed data about participants, therapies, organ assessments, death declaration procedures and adverse clinical exposures from the time of donation consent to organ recovery. ODOs provide reasons that organs are declined, dates and places of transplantation, and recipient age and sex.Descriptive analyses will summarise current practices. Effectiveness analyses will examine donation-specific interventions with respect to the number of transplants, using multilevel regression models to account for clustering by donor, hospitals and ODOs. Feasibility analyses will focus on acceptance of the research consent model; participation of academic and community hospitals as well as ODOs; and accessibility of recipient data.

ETHICS AND DISSEMINATION

This study uses a waiver of research consent. Hospitals will receive reports on local practices benchmarked to (1) national practices and (2) national donor management guidelines. We will report findings to donation and transplant collaborators (ie, clinicians, researchers, ODOs) and publish in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT03114436.

The Use of Stroke Volume Variation to Guide Donor Management Is Associated With Increased Organs Transplanted per Donor

BACKGROUND

There is a national shortage of organs available for transplantation, and utilization rates for thoracic organs are less than 40%. In addition, the optimal method of assessing cardiovascular status during donor management is uncertain. FloTrac is a noninvasive hemodynamic technique that measures cardiac output and fluid responsiveness. Our objective was to measure the impact of using this technique to guide management on fluid balance, vasopressor usage, thyroid hormone usage, and pulmonary function. We hypothesized that FloTrac guidance will increase thoracic organs transplanted per donor (OTPD).

METHODS

Data were prospectively collected on a convenience sample of 38 donors after neurologic determination of death. Organs transplanted, net fluid balance, dosage of vasopressors, dosage of thyroid hormone, and Pao₂:Fio₂ were compared between treatment and control groups.

RESULTS

The treatment group had greater thoracic OTPD (1.3 [1.0] vs 0.4 [0.6], P = .004) and overall OTPD (4.3 [1.5] vs 2.7 [1.5], P = .002). Donors in the treatment group maintained a neutral fluid balance, had more thyroid hormone used, and had an improvement in oxygenation.

CONCLUSION

The implementation of this technology to aid providers may help ameliorate the shortage of thoracic and overall organs available for transplantation.

Recommendations for further improvement of the deceased organ donation process in Belgium

Belgium has achieved high deceased organ donation rates but according to the medical record data in the Donor Action database, deceased potential donors are still missed along the pathway. Between 2010 and 2014, 12.9 ± 3.3% of the potential donors after brain death (DBD) and 24.6 ± 1.8% of the potential donors after circulatory (DCD) death were not identified. Conversion rates of 41.7 ± 2.1% for DBD and 7.9 ± 0.9% for DCD indicate room for further improvement. We identify and discuss different issues in the monitoring of donation activities, practices and outcomes; donor pool; legislation on deceased organ donation; registration; financial reimbursement; educational and training programs; donor detection and practice clinical guidance. The overall aim of this position paper, elaborated by a Belgian expert panel, is to provide recommendations for further improvement of the deceased organ donation process up to organ procurement in Belgium.