Management of the Potential Organ Donor in the ICU: Society of Critical Care Medicine/American College of Chest Physicians/Association of Organ Procurement Organizations Consensus Statement. Crit Care Med. 2015;43:1291-1325. [PMID: 25978154 DOI: 10.1097/ccm.0000000000000958]

Organ donation after out-of-hospital cardiac arrest: a population-based study of data from the Paris Sudden Death Expertise Center

BACKGROUND

Organ shortage is a major public health issue, and patients who die after out-of-hospital cardiac arrest (OHCA) could be a valuable source of organs. Here, our objective was to identify factors associated with organ donation after brain death complicating OHCA, in unselected patients entered into a comprehensive real-life registry covering a well-defined geographic area.

METHODS

We prospectively analyzed consecutive adults with OHCA who were successfully resuscitated, but died in intensive care units in the Paris region in 2011-2018. The primary outcome was organ donation after brain death. Independent risk factors were identified using logistic regression analysis. One-year graft survival was assessed using Cox and log-rank tests.

RESULTS

Of the 3061 included patients, 136 (4.4%) became organ donors after brain death, i.e., 28% of the patients with brain death. An interaction between admission pH and post-resuscitation shock was identified. By multivariate analysis, in patients with post-resuscitation shock, factors associated with organ donation were neurological cause of OHCA (odds ratio [OR], 14.5 [7.6-27.4], P < 0.001), higher pH (OR/0.1 increase, 1.3 [1.1-1.6], P < 0.001); older age was negatively associated with donation (OR/10-year increase, 0.7 [0.6-0.8], P < 0.001). In patients without post-resuscitation shock, the factor associated with donation was neurological cause of OHCA (OR, 6.9 [3.0-15.9], P < 0.001); higher pH (OR/0.1 increase, 0.8 [0.7-1.0], P = 0.04) and OHCA at home (OR, 0.4 [0.2-0.7], P = 0.006) were negatively associated with organ donation. One-year graft survival did not differ according to Utstein characteristics of the donor.

CONCLUSIONS

4% of patients who died in ICU after OHCA led to organ donation. Patients with OHCA constitute a valuable source of donated organs, and special attention should be paid to young patients with OHCA of neurological cause.

Specialized Donor Care Facility Model and Advances in Management of Thoracic Organ Donors

BACKGROUND

Donor hearts and lungs are more susceptible to the inflammatory physiologic changes that occur after brain death. Prior investigations have shown that protocolized management of potential organ donors can rehabilitate donor organs that are initially deemed unacceptable. In this review we discuss advances in donor management models with particular attention to the specialized donor care facility model. In addition we review specific strategies to optimize donor thoracic organs and improve organ yield in thoracic transplantation.

METHODS

We performed a literature review by searching the PubMed database for medical subject heading terms associated with organ donor management models. We also communicated with our local organ procurement organization to gather published and unpublished information first-hand.

RESULTS

The specialized donor care facility model has been shown to improve the efficiency of organ donor management and procurement while reducing costs and minimizing travel and its associated risks. Lung protective ventilation, recruitment of atelectatic lung, and hormone therapy (eg, glucocorticoids and triiodothyronine/thyroxine) are associated with improved lung utilization rates. Stroke volume-based resuscitation is associated with improved heart utilization rates, whereas studies evaluating hormone therapy (eg, glucocorticoids and triiodothyronine/thyroxine) have shown variable results.

CONCLUSIONS

Lack of high-quality prospective evidence results in conflicting practices across organ procurement organizations, and best practices remain controversial. Future studies should focus on prospective, randomized investigations to evaluate donor management strategies. The specialized donor care facility model fosters a collaborative environment that encourages academic inquiry and is an ideal setting for these investigations.

Pig-to-human kidney transplantation using brain-dead donors as recipients: One giant leap, or only one small step for transplantkind?

Pig kidney xenotransplantation is increasingly regarded as a realistic solution to the current shortage of human organ donors for patients with end-stage organ failure. Recently, the news of three pig-to-human transplantation cases has awakened public interest. Notably, the case by the Alabama team reported detailed and important findings for the xenotransplantation field. Using a genetically modified pig, two porcine kidneys were transplanted into a brain-dead recipient. They applied several approaches established in the preclinical NHP study, including gene-edited pig kidney graft and preoperative laboratory inspection such as crossmatching and infection screening. The pig-to-human kidney xenotransplantation had no unexpected events during surgery or evidence of hyperacute rejection. Unfortunately, the grafts did not work appropriately, and the study had to be terminated due to the decompensation of the recipient. While this study demonstrated the outstanding achievement in this research area, it also revealed remaining gaps to move xenotransplantation to the clinic. While brain-dead human recipients could reinforce the compatibility achievements of gene-edited pigs in NHP, their pro-inflammatory and pro-coagulant environment, in combination with short-duration of experiments will limit the assessment of kidney function, infection and rejection risk post-transplant, in particular antibody-mediated rejection. The use of successful immunosuppressive protocols of non-human primates xenotransplant experiments including anti-CD154 antibody will be critical to maximize the success in the first in-human trials.

Centralized Organ Recovery and Reconditioning Centers

An increased focus on improving efficiency and decreasing costs has resulted in alternative models of donor management and organ recovery. The specialized donor care facility model provides highly efficient and cost-effective donor care at a free-standing facility, resulting in improved organ yield, shorter ischemic times, decreased travel, and fewer nighttime operations. Ex vivo lung perfusion (EVLP) improves utilization of extended criteria donor lungs, and centralized EVLP facilities have the potential to increase transplant volumes for smaller transplant programs in specified geographic regions. These alternative models are increasingly being used in the United States to improve waitlist mortality and combat the ongoing donor organ shortage.

Management of the Potential Lung Donor

The use of donor management protocols has significantly improved recovery rates; however, the inherent instability of lungs after death results in low utilization rates of potential donor lungs. Donor lungs are susceptible to direct trauma, aspiration, neurogenic edema, ventilator-associated barotrauma, and ventilator-associated pneumonia. After irreversible brain injury and determination of futility of care, the goal of medical management of the donor shifts to maintaining hemodynamic stability and maximizing the likelihood of successful organ recovery.

Donation after circulatory death and lung transplantation

Lung transplantation is the most effective modality for the treatment of patients with end-stage lung diseases. Unfortunately, many people cannot benefit from this therapy due to insufficient donor availability. In this review and update article, we discuss donation after circulatory death (DCD), which is undoubtedly essential among the strategies developed to increase the donor pool. However, there are ethical and legislative considerations in the DCD process that are different from those of donation after brain death (DBD). Among others, the critical aspects of DCD are the concept of the end of life, cessation of futile treatments, and withdrawal of life-sustaining therapy. In addition, this review describes a rationale for using lungs from DCD donors and provides some important definitions, highlighting the key differences between DCD and DBD, including physiological aspects pertinent to each category. The unique ability of lungs to maintain cell viability without circulation, assuming that oxygen is supplied to the alveoli-an essential aspect of DCD-is also discussed. Furthermore, an updated review of the clinical experience with DCD for lung transplantation across international centers, recent advances in DCD, and some ethical dilemmas that deserve attention are also reported.

Can adequate hemodynamic management of brain-dead donors improve donor organ procurement?

There is increasing evidence that adequate donor management with a goal of optimization of organ function is essential to maximize the number of organs that can be procured. Therefore, identification of the cause of hemodynamic instability is crucial in order to direct the right therapy. Several donor management goals for better hemodynamic management including serial echocardiography can guide hemodynamic management in potential donors to increase both number and quality of donor hearts.

The Suitability of Potential Organ Donors Using Real Case-Scenarios; Do we Need to Create a "Donor Board" Process for Donors Perceived as Unlikely Suitable?

Introduction: Despite availability of selection criteria, different interpretations can lead to variability in the appreciation of donor eligibility with possible viable organs missed. Our primary objective was to test the perception of feasibility of potential organ donors through the survey of a small sample of external evaluators.

Methods: Clinical scenarios summarizing 66 potential donors managed in the first year of our Organ Recovery Center were sent to four critical care physicians to evaluate the feasibility of the potential donors and the probability of organ procurement.

Results: Potential donors procuring at least one organ were identified in 55 of the 66 cases (83%). Unanimity was reached in 38 cases, encompassing 35 out of the 55 converted and 3 of the non-converted donors. The overall agreement was moderate (kappa = 0.60, 95% CI: 0.37–0.82). For the organs finally procured for transplantation, organ donation was predicted for the majority of the cases, but high discrepancy was present with the final outcome of organs not procured (particularly liver and kidney).

Conclusion: The assessment of a potential donor is a complex dynamic process. In order to increase organ availability, standardized electronically clinical data, as well a “donor board” structure of decision might inform future systems.

Evaluation of donor heart for transplantation

Cardiac transplantation is considered the gold-standard treatment option for patients suffering from end-stage heart failure refractory to maximum medical therapy. A major determinant of graft function and recipient survival is a comprehensive evaluation of the donor allograft. Challenges arise when designing and implementing an evidence-based donor evaluation protocol due to the number of influential donor-specific characteristics and the complex interactions that occur between them. Here, we present our systematic approach to donor evaluation by examining the impact that relevant donor variables have on graft function and recipient outcomes.

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.

Current status of glucocorticoid usage in solid organ transplantation

Glucocorticoids (GCs) have been the mainstay of immunosuppressive therapy in solid organ transplantation (SOT) for decades, due to their potent effects on innate immunity and tissue protective effects. However, some SOT centers are reluctant to administer GCs long-term because of the various related side effects. This review summarizes the advantages and disadvantages of GCs in SOT. PubMed and Scopus databases were searched from 2011 to April 2021 using search syntaxes covering “transplantation” and “glucocorticoids”. GCs are used in transplant recipients, transplant donors, and organ perfusate solution to improve transplant outcomes. In SOT recipients, GCs are administered as induction and maintenance immunosuppressive therapy. GCs are also the cornerstone to treat acute antibody- and T-cell-mediated rejections. Addition of GCs to organ perfusate solution and pretreatment of transplant donors with GCs are recommended by some guidelines and protocols, to reduce ischemia-reperfusion injury peri-transplant. GCs with low bioavailability and high potency for GC receptors, such as budesonide, nanoparticle-mediated targeted delivery of GCs to specific organs, and combination use of dexamethasone with inducers of immune-regulatory cells, are new methods of GC application in SOT patients to reduce side effects or induce immune-tolerance instead of immunosuppression. Various side effects involving different non-targeted organs/tissues, such as bone, cardiovascular, neuromuscular, skin and gastrointestinal tract, have been noted for GCs. There are also potential drug-drug interactions for GCs in SOT patients.

Endocrine Management and Hormone Replacement Therapy in Cardiac Donor Management: A Retrospective Observational Study

BACKGROUND

Pituitary dysfunction after brainstem death can cause various hormone deficiencies in potential heart donors. The aim of this study was to evaluate the relationship between hormone replacement therapy (HRT; including antidiuretic hormone analog, thyroid hormone, and methylprednisolone) in heart donors and the recipients' outcomes after heart transplantation (HTx).

METHODS

We retrospectively analyzed HTxs performed between January 2012 and October 2018. Donor and recipient characteristics were retrieved with a focus on endocrine parameters and HRT. The primary outcome was primary graft dysfunction (PGD). Secondary outcomes were the 30-day and 2-year mortality of the recipients. Univariate and multivariate Cox regression analyses were applied.

RESULTS

The study included 297 HTxs. PGD occurred in 56 recipients (18.9%). In the multivariable Cox analysis, methylprednisolone and thyroxine treatment in donors were associated with a lower odds for PGD (odds ratio [OR], 0.43; 95% CI, 0.19-1.01; P = .052; and OR,: 0.34; 95% CI, 0.15-0.76; P = .009, respectively). In multivariate analysis, thyroxine treatment in donors was associated with a lower odds of PGD (OR, 0.38; 95% CI, 0.17-0.86; P = .020). Donor thyroxine supplementation also had a beneficial effect on recipients' 2-year survival (OR, 0.53; 95% CI, 0.29-0.96; P = .036).

CONCLUSIONS

Combined thyroxine and methylprednisolone treatment could be a protective factor against PGD. Thyroxine administration was associated with better 2-year survival in recipients.

[Perioperative management of the brain-dead organ donor : Anesthesia between ethics and evidence]

Hintergrund

Die Anzahl postmortal gespendeter Organe ist in Deutschland weit geringer als der Bedarf. Dies unterstreicht die Wichtigkeit einer optimalen Versorgung während des gesamten Prozesses der Organspende.

Fragestellung

Es existieren internationale Leitlinien und nationale Empfehlungen zu intensivmedizinischen organprotektiven Maßnahmen beim Organspender. Für das anästhesiologische Management fehlen evidenzbasierte Empfehlungen. Ziel dieser Übersichtsarbeit ist es, anhand der vorhandenen Evidenz die pathophysiologischen Veränderungen des irreversiblen Hirnfunktionsausfalls zu rekapitulieren und sich kritisch mit den empfohlenen Behandlungsstrategien und therapeutischen Zielgrößen auseinanderzusetzen. Auch auf ethische Aspekte der Betreuung des postmortalen Organspenders wird eingegangen.

Methode

Diese Übersichtsarbeit basiert auf einer selektiven Literaturrecherche in PubMed (Suchwörter: „brain dead donor“, „organ procurement“, „organ protective therapy“, „donor preconditioning“, „perioperative donor management“, „ethical considerations of brain dead donor“). Internationale Leitlinien und nationale Empfehlungen wurden besonders berücksichtigt.

Ergebnisse

Insgesamt ist die Evidenz für optimale intensivmedizinische und perioperative organprotektive Maßnahmen beim postmortalen Organspender sehr gering. Nationale und internationale Empfehlungen zu Zielwerten und medikamentösen Behandlungsstrategien unterscheiden sich teilweise erheblich: kontrollierte randomisierte Studien fehlen. Der Stellenwert einer Narkose zur Explantation bleibt sowohl unter pathophysiologischen Gesichtspunkten als auch aus ethischer Sicht ungeklärt.

Schlussfolgerungen

Die Kenntnisse über die pathophysiologischen Prozesse im Rahmen des irreversiblen Hirnfunktionsausfalls und die organprotektiven Maßnahmen sind ebenso Grundvoraussetzung wie die ethische Auseinandersetzung mit dem Thema postmortale Organspende. Nur dann kann das Behandlungsteam in dieser herausfordernden Situation sowohl dem Organempfänger als auch dem Organspender und seinen Angehörigen gerecht werden.

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.

Effects of Terlipressin on Management of Hypotensive Brain-Dead Patients Who are Potential Organ Donors: A Retrospective Study

Background: Administration of terlipressin can reverse hypotension in potential organ donors with norepinephrine-resistance. The aim of this study was to determine the effects of terlipressin on the hemodynamics, liver function, and renal function of hypotensive brain-dead patients who were potential organ donors.

Methods: A retrospective study was conducted by using the ICU database of one hospital. 18 patients in a total of 294 brain-dead cases were enrolled and administered terlipressin intravenously. All physiological parameters of recruited patients were obtained at baseline, 24 and 72 h after administration, and immediately before organ procurement.

Results: Terlipressin induced significant increases in mean arterial pressure (MAP) from 69.56 ± 10.68 mm Hg (baseline) to 101.82 ± 19.27 mm Hg (immediately before organ procurement) and systolic blood pressure (SBP) from 89.78 ± 8.53 mm Hg (baseline) to 133.42 ± 26.11 mm Hg (immediately before organ procurement) in all patients. The increases in MAP were accompanied by significant decreases in heart rate (HR) from 113.56 ± 28.43 bpm (baseline) to 83.89 ± 11.70 bpm (immediately before organ procurement), which resulted in the decrease of norepinephrine dose over time from 0.8 ± 0.2 μg/kg/min (baseline) to 0.09 ± 0.02 μg/kg/min (immediately before organ procurement). There were no changes in central venous pressure, liver function including aspartate aminotransferase (AST), alanine aminotransferase (ALT), and bilirubin. Renal function, assessed by serum creatinine (SCr), urine output (UOP), creatinine clearance rate (CCr), and estimated glomerular filtration rate (eGFR), improved significantly.

Conclusion: Our analysis of brain-dead patients with hypotension indicates that administration of terlipressin can significantly increases MAP, SBP, UOP, CCr, and eGFR, while decreases HR and Scr. Terlipressin appears to help maintain hemodynamic stability, reduce vasoactive support, and improve renal function.

Management of the brain-dead organ donor

Organ transplantation is a life-saving intervention for patients suffering from end-stage organ failure, but it relies on the availability of donor organs. However, even when donors are available, the brain-dead organ donor is a clinically complex patient who presents many management challenges. Donor management with a goal of optimization of organ function is essential to maximizing the number of patients who can be helped by each individual donor. Thoughtful critical care management of the potential organ donor, with a focus on meeting donor management goals, can lead to improved donation outcomes.

Successful strategies to increase organ donation: the Gift of Life Donor Program Philadelphia model

Organ donation connects the ending of one life with the renewal of another. Acute care hospitals care for the organ donor and transplant organizations complete life-saving surgeries. Between them is a vital component: a less-known medical team dedicated to ensuring that organ donation and transplantation are possible. Organ procurement organizations (OPOs) support grieving families during a painful time of loss, providing a rare and precious opportunity in donation. The OPO is simultaneously poised to ensure that organs successfully begin their journey to renewing life and restoring hope for recipients and their loved ones. Every OPO faces a myriad of challenges in meeting its responsibilities. A recognized leader in the field, Gift of Life Donor Program (GLDP) in Philadelphia, Pennsylvania has been committed to meeting these challenges for nearly fifty years. The successes of this OPO reflect the legacies of organ donors, recipients, and their cherished loved ones.

[Organ donation: A treatment option in end-of life intensive care?]

A newly issued policy statement of the German Medical Association considers organ donation as an integral part of end-of-life intensive care in patients with devastating brain afflictions. Hence, patients' wishes towards organ donation and medical suitability should be evaluated when prognosis is considered futile and goals of treatment need to be reconsidered. Continuation of intensive care treatment towards the (mandatory) diagnosis of "brain death" and subsequently towards organ donation has to be legitimatized by patients' explicit wishes (organ donor card, advanced directive) or by surrogate decisions makers. Intensive care facilitating organ donation should be goal-directed and follow established guidelines. Thus, a potential recovery of transplantable organs is supported by appropriate intensive care treatment. Decisions to employ extended intensive care options (like extracorporeal circulatory support or cardiopulmonary resuscitation) in potential organ donors should be carefully outbalanced with patients' wishes, organ donation being considered an achievable goal and even potential frictions in medical teams.

US deceased kidney transplantation: Estimated GFR, donor age and KDPI association with graft survival

BACKGROUND

Despite a significant shortage of kidneys for transplantation in the US, kidneys from older deceased donors are infrequently transplanted. This is primarily over concern of graft quality and transplant durability.

METHODS

The US national transplant database (2000-2018) was assessed for deceased donor kidney transplant patient and graft survival, graft durability and stratified by donor age (<65 years>), Kidney Donor Profile Index (KDPI) and estimated glomerual filtration rate (GFR) one year post-transplantation (eGFR-1) were calculated.

FINDINGS

Recipients of kidneys transplanted from deceased donors >65 years had a lower eGFR-1, (median 39 ml/min) than recipients of younger donor kidneys (median 54 ml/min). However, death-censored graft survival, stratified by eGFR-1, demonstrated similar survival, irrespective of donor age or KDPI. The durability of kidney survival decreases as the achieved eGFR-1 declines. KDPI has a poor association with eGFR-1 and lesser for graft durability. While recipients of kidneys > 65 years had a higher one year mortality than younger kidney recipients, recipients of kidneys > 65 years and an eGFR-1 <30 ml/min, had a lower survival than an untransplanted waitlist cohort (p<0.001).

INTERPRETATION

The durability of kidney graft survival after transplantation was associated with the amount of kidney function gained through the transplant (eGFR-1) and the rate of graft loss (return to dialysis) was not significantly associated with donor age. 24.9% of recipients of older donor kidneys failed to achieve sufficient eGFR-1 providing a transplant survival benefit. While there is significant benefit from transplanting older kidneys, better decision-making tools are required to avoid transplanting kidneys that provide insufficient renal function.

FUNDING

None.

Imaging Course of Lung Transplantation: From Patient Selection to Postoperative Complications

Lung transplant is increasingly performed for the treatment of end-stage lung disease. As the number of lung transplants and transplant centers continues to rise, radiologists will more frequently participate in the care of patients undergoing lung transplant, both before and after transplant. Potential donors and recipients undergo chest radiography and CT as part of their pretransplant assessment to evaluate for contraindications to transplant and to aid in surgical planning. After transplant, recipients undergo imaging during the postoperative hospitalization and also in the long-term outpatient setting. Radiologists encounter a wide variety of conditions leading to end-stage lung disease and a myriad of posttransplant complications, some of which are unique to lung transplantation. Familiarity with these pathologic conditions, including their imaging findings and their temporal relationship to the transplant, is crucial to accurate radiologic interpretation. Knowledge of the surgical techniques and expected postoperative appearance prevents confusing normal posttransplant imaging findings with complications. A basic understanding of the indications, contraindications, and surgical considerations of lung transplant aids in imaging interpretation and protocoling and also facilitates communication between radiologists and transplant physicians. Despite medical and surgical advances over the past several decades, lung transplant recipients currently have an average posttransplant life expectancy of only 6.7 years. As members of the transplant team, radiologists can help maximize patient survival and hopefully increase posttransplant life expectancy and quality of life in the coming decades. ^©RSNA, 2021 An invited commentary by Bierhals is available online. Online supplemental material is available for this article.

Whole Blood Thiamine in Organ Donors After the Neurologic Determination of Death

INTRODUCTION

Metabolic resuscitation of organ donors and the attenuation of oxidative stress incurred by organs following brain death and transplantation have the potential to improve organ yield and allograft function. Thiamine (vitamin B1) is a vital coenzyme in both energy metabolism and the production of antioxidants that has not been studied in the donor population.

RESEARCH AIM

To determine the frequency of subclinical thiamine deficiency in brain-dead organ donors and its correlation with demographics, length of hospitalization, donor management, lactic acidosis, and the requirement for vasoactive support.

DESIGN

Prospective cohort study of brain-dead donors managed at a single organ procurement organization's organ recovery facility.

RESULTS

A total 64 donors were enrolled; 24 donors had thiamine levels drawn upon arrival and 40 donors had levels drawn at the time of organ procurement. Whole blood thiamine levels were inversely correlated with the time from death (P = .007) and 20% (8/40) of donors had levels below the normal range at the time of organ procurement. Demographic features of the donor were not associated with thiamine levels although longer hospital stays prior to death were associated with lower levels (P < .05). The presence and resolution of lactic acidosis was not associated with whole blood thiamine level. Higher thiamine levels were associated with earlier discontinuation of vasoactive support (P = .04).

DISCUSSION

Whole blood thiamine deficiency was not uncommon at the time of organ procurement. Thiamine may be associated with the requirement for hemodynamic support.

Bacterial Pneumonia in Brain-Dead Patients: Clinical Features and Impact on Lung Suitability for Donation

OBJECTIVES

To appraise the epidemiological features of bacterial pneumonia and its impact on lung suitability for donation in brain-dead patients managed with protective ventilatory settings.

DESIGN

Retrospective observational study.

SETTING

Six ICUs from two university-affiliated hospitals.

PATIENTS

Brain-dead adult patients managed in the participating ICUs over a 4-year period.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Among the 231 included patients, 145 (62.8%) were classified as ideal or extended-criteria potential lung donors at ICU admission and the remaining 86 patients having baseline contraindication for donation. Culture-proven aspiration pneumonia and early-onset ventilator-associated pneumonia occurred in 54 patients (23.4%) and 15 patients (6.5%), respectively (overall pneumonia incidence, 29.9%). Staphylococcus aureus and Enterobacterales were the most common pathogens. Using mixed-effects Cox proportional hazard models, age (adjusted hazard ratio, 0.98; 95% CI [0.96-0.99]), anoxic brain injury (3.55 [1.2-10.5]), aspiration (2.29 [1.22-4.29]), and not receiving antimicrobial agents at day 1 (3.56 [1.94-6.53]) were identified as independent predictors of pneumonia occurrence in the whole study population. Analyses restricted to potential lung donors yielded similar results. Pneumonia was associated with a postadmission decrease in the PaO2/FIO2 ratio and lower values at brain death, in the whole study population (estimated marginal mean, 294 [264-323] vs 365 [346-385] mm Hg in uninfected patients; p = 0.0005) as in potential lung donors (299 [248-350] vs 379 [350-408] mm Hg; p = 0.04; linear mixed models). Lungs were eventually retrieved in 31 patients (34.4%) among the 90 potential lung donors with at least one other organ harvested (pneumonia prevalence in lung donors (9.7%) vs nondonors (49.2%); p = 0.0002).

CONCLUSIONS

Pneumonia occurs in one-third of brain-dead patients and appears as the main reason for lung nonharvesting in those presenting as potential lung donors. The initiation of antimicrobial prophylaxis upon the first day of the ICU stay in comatose patients with severe brain injury could enlarge the pool of actual lung donors.

Coronary angiography utilization in the evaluation of a potential heart donor by age: a narrative review

Heart transplant is the gold standard treatment for patients with heart failure. The limitation to providing heart transplantation to patients suffering from end stage heart disease is the stable organ supply within the United States despite increasing demand. Transplant centers across the United States have begun to expand traditional cardiac donor selection metrics previously utilized. As a result, the use of extended criteria donors, such as older donors, those with longer ischemic times, and donors considered high risk has increased. Current guidelines suggest that coronary angiography be performed when evaluating a donor above the age of 45. Angiographic guidelines for evaluation of the donor heart are based specifically on age, with little evidence based guidance surrounding the use of angiography in a younger donor with comorbidities or increased risk behavior which may lead to premature coronary artery disease. Recently, we have seen an increase in younger heart donors, many of whom have succumbed due to drug overdose with ensuing high risk behaviors. Given the increased risk nature of these donors, consideration of performing coronary angiography is determined by clinical “gestalt” of the transplant center evaluating the heart for use, which may lead to underutilization of donor organs without evidence to support the practice. Here, we review the guidelines, literature, and controversy surrounding the use of coronary angiography in evaluating donor hearts for transplantation.

Organ Donation Authorization After Brain Death Among Patients Admitted to PICUs in the United States, 2009-2018

OBJECTIVES

To identify trends in and factors associated with pediatric organ donation authorization after brain death.

DESIGN

Retrospective cohort study of data from Virtual Pediatric Systems, LLC (Los Angeles, CA).

SETTING

Data from 123 PICUs reporting to Virtual Pediatric Systems from 2009 to 2018.

PATIENTS

Patients less than 19 years old eligible for organ donation after brain death.

MEASUREMENTS AND MAIN RESULTS

Of 2,777 eligible patients, 1,935 (70%) were authorized for organ donation; the authorization rate remained unchanged over time (ptrend = 0.22). In a multivariable logistic regression model, hospitalizations lasting greater than 7 days had lower odds of authorization (adjusted odds ratio, 0.5; p < 0.001 vs ≤ 1 d) and White patients had higher odds than other race/ethnicity groups. Authorization was higher for trauma-related encounters (adjusted odds ratio, 1.5; p < 0.001) and when donation was discussed with an organ procurement organization coordinator (adjusted odds ratio, 1.7; p < 0.001). Of 123 hospitals, 35 (28%) met or exceeded a 75% organ donation authorization target threshold; these hospitals more often had an organ procurement organization coordinator discussing organ donation (85% vs 72% of encounters; p < 0.001), but no difference was observed by PICU bed size.

CONCLUSIONS

Organ donation authorization after brain death among PICU patients was associated with length of stay, race/ethnicity, and trauma-related encounter, and authorization rates were higher when an organ procurement organization coordinator was involved in the donation discussion. This study identified factors that could inform initiatives to improve the authorization process and increase pediatric organ donation rates.

Hypothalamic function in patients diagnosed as brain dead and its practical consequences

Some patients who have been diagnosed as "dead by neurologic criteria" continue to exhibit certain brain functions, most commonly, neuroendocrine functions. In this chapter, we review the pathophysiology of brain death that can lead either to neuroendocrine failure or to preserved neuroendocrine functioning. We review the evidence on continued hypothalamic functioning in patients who have been declared "brain dead," examine potential mechanisms that would explain these findings, and discuss how these findings create additional confounds for brain death testing. We conclude by reviewing the evidence for the management of hypothalamic-pituitary failure in the setting of brain death and organ transplantation.

Brazilian guidelines for the management of brain-dead potential organ donors. The task force of the AMIB, ABTO, BRICNet, and the General Coordination of the National Transplant System

OBJECTIVE

To contribute to updating the recommendations for brain-dead potential organ donor management.

METHOD

A group of 27 experts, including intensivists, transplant coordinators, transplant surgeons, and epidemiologists, joined a task force formed by the General Coordination Office of the National Transplant System/Brazilian Ministry of Health (CGSNT-MS), the Brazilian Association of Intensive Care Medicine (AMIB), the Brazilian Association of Organ Transplantation (ABTO), and the Brazilian Research in Intensive Care Network (BRICNet). The questions were developed within the scope of the 2011 Brazilian Guidelines for Management of Adult Potential Multiple-Organ Deceased Donors. The topics were divided into mechanical ventilation, hemodynamic support, endocrine-metabolic management, infection, body temperature, blood transfusion, and use of checklists. The outcomes considered for decision-making were cardiac arrest, number of organs recovered or transplanted per donor, and graft function/survival. Rapid systematic reviews were conducted, and the quality of evidence of the recommendations was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. Two expert panels were held in November 2016 and February 2017 to classify the recommendations. A systematic review update was performed in June 2020, and the recommendations were reviewed through a Delphi process with the panelists between June and July 2020.

RESULTS

A total of 19 recommendations were drawn from the expert panel. Of these, 7 were classified as strong (lung-protective ventilation strategy, vasopressors and combining arginine vasopressin to control blood pressure, antidiuretic hormones to control polyuria, serum potassium and magnesium control, and antibiotic use), 11 as weak (alveolar recruitment maneuvers, low-dose dopamine, low-dose corticosteroids, thyroid hormones, glycemic and serum sodium control, nutritional support, body temperature control or hypothermia, red blood cell transfusion, and goal-directed protocols), and 1 was considered a good clinical practice (volemic expansion).

CONCLUSION

Despite the agreement among panel members on most recommendations, the grade of recommendation was mostly weak. The observed lack of robust evidence on the topic highlights the importance of the present guideline to improve the management of brain-dead potential organ donors.

Circadian Pattern of Ion Channel Gene Expression in Failing Human Hearts

BACKGROUND

Ventricular tachyarrhythmias and sudden cardiac death show a circadian pattern of occurrence in patients with heart failure. In the rodent ventricle, a significant portion of genes, including some ion channels, shows a circadian pattern of expression. However, genes that define electrophysiological properties in failing human heart ventricles have not been examined for a circadian expression pattern.

METHODS

Ventricular tissue samples were collected from patients at the time of cardiac transplantation. Two sets of samples (n=37 and 46, one set with a greater arrhythmic history) were selected to generate pseudo-time series according to their collection time. A third set (n=27) of samples was acquired from the nonfailing ventricles of brain-dead donors. The expression of 5 known circadian clock genes and 19 additional ion channel genes plausibly important to electrophysiological properties were analyzed by real-time polymerase chain reaction and then analyzed for the percentage of expression variation attributed to a 24-hour circadian pattern.

RESULTS

The 5 known circadian clock gene transcripts showed a strong circadian expression pattern. Compared with rodent hearts, the human circadian clock gene transcripts showed a similar temporal order of acrophases but with a ≈7.6 hours phase shift. Five of the ion channel genes also showed strong circadian expression. Comparable studies of circadian clock gene expression in samples recovered from nonheart failure brain-dead donors showed acrophase shifts, or weak or complete loss of circadian rhythmicity, suggesting alterations in circadian gene expression.

CONCLUSIONS

Ventricular tissue from failing human hearts display a circadian pattern of circadian clock gene expression but phase-shifted relative to rodent hearts. At least 5 ion channels show a circadian expression pattern in the ventricles of failing human hearts, which may underlie a circadian pattern of ventricular tachyarrhythmia/sudden cardiac death. Nonfailing hearts from brain-dead donors show marked differences in circadian clock gene expression patterns, suggesting fundamental deviations from circadian expression.

Expedited organ donation in Victoria, Australia: donor characteristics and donation outcomes

Background: Deceased organ donation work-up typically takes 24 hours or more. Clinicians may thus discount the possibility of donation when the potential donor is physiologically unstable or family requirements do not allow this length of time. This may lead to loss of transplantable organs. In 2015, we introduced an expedited work-up guideline with the aim of facilitating donation in these circumstances and maximising donation potential. Objective: To determine the number of expedited work-up (consent to retrieval procedure of 6 hours or less) donors from 2015 to 2018, compare their clinical and demographic characteristics with standard donors, and assess the outcome of transplanted organs and organ recipients. Design: We performed a retrospective audit of the electronic database for all Victorian donors from 2015 to 2018. We obtained transplant outcome data from the Australia and New Zealand Dialysis and Transplant Registry (ANZDATA). Results: Overall, 38 expedited pathway donors donated 78 organs for transplantation (70 kidneys, four lungs, three livers, one pancreas). Of these, 55 retrieved kidneys were successfully transplanted. The lungs, livers and pancreas retrieved were all transplanted. For the kidney recipients, early graft dysfunction requiring dialysis was more common than with organs from the standard pathway (71% v 38%; P < 0.0001); however, short and medium term graft and patient survival were similar. Three recipients from the expedited pool experienced graft failure and two subsequently died. Of the two lung recipients, one died at day 622 of chronic rejection. Conclusions: Expedited pathway donation is feasible with acceptable donation outcomes. Clinicians should consider donation even when physiological instability or family requirements preclude standard organ donation work-up times.

Worldwide management of donors after neurological death: a systematic review and narrative synthesis of guidelines

OBJECTIVE

The objectives of this study were to systematically identify and describe guidelines for the care of neurologically deceased donors and to evaluate their methodological quality, with the aim of informing and supporting the new Canadian guidelines for the management of organ donors.

METHODOLOGY

Following a systematic search, we included any document endorsed by an organ donation organization, a professional society, or a government, that aims to direct the medical management of adult, neurologically deceased, multi-organ donors. We extracted recommendations pertaining to six domains: the autonomic storm, hemodynamic instability, hormone supplementation, ventilation, blood product transfusions, and general intensive care unit (ICU) care. Methodological quality of the guidelines was assessed by the validated AGREE-II tool.

MAIN FINDINGS

This review includes 27 clinical practice guidelines representing 26 countries published between 1993 and 2019. Using the AGREE-II validated tool for the evaluation of guidelines' quality, documents generally scored well on their scope and clarity of presentation. Nevertheless, quality was limited in terms of the scientific rigor of guideline development. Recommendations varied substantially across the domains of managing the autonomic storm, subsequent management of hemodynamic instability, hormone therapy, mechanical ventilation, blood product transfusion, and general ICU care. We found consistent recommendations for low tidal volume ventilation subsequent to the publication of a landmark clinical trial.

CONCLUSION

Highly inconsistent recommendations for deceased donor care summarized in this review likely reflect the relatively slow emergence of high-quality clinical research in this field, as well as a late uptake of recent validated guideline methodology. Even in this context of few randomized-controlled trials, our group supported the need for new Canadian guidelines for the management of organ donors that follow rigorous recognized methodology and grading of the evidence.

TRIAL REGISTRATION

PROSPERO (CRD42018084012); registered 25 February 2016.

Vasopressor selection during critical care management of brain dead organ donors and the effects on kidney graft function

BACKGROUND

Delayed graft function (DGF), the need for dialysis in the first week following kidney transplant, affects approximately one quarter of deceased-donor kidney transplant recipients. Donor demographics, donor serum creatinine, and graft cold ischemia time are associated with DGF. However, there is no consensus on the optimal management of hemodynamic instability in organ donors after brain death (DBDs). Our objective was to determine the relationship between vasopressor selection during donor management and the development of DGF.

METHODS

Prospective observational data, including demographic and critical care parameters, were collected for all DBDs managed by 17 organ procurement organizations from nine Organ Procurement and Transplantation Network Regions between 2012 and 2018. Recipient outcome data were linked with donor data through donor identification numbers. Donor critical care parameters, including type of vasopressor and doses, were recorded at three standardized time points during donor management. The analysis included only donors who received at least one vasopressor at all three time points. Vasopressor doses were converted to norepinephrine equivalent doses and analyzed as continuous variables. Univariate analyses were conducted to determine the association between donor variables and DGF. Results were adjusted for known predictors of DGF using binary logistic regression.

RESULTS

Complete data were available for 5,554 kidney transplant recipients and 2,985 DBDs. On univariate analysis, donor serum creatinine, donor age, donor subtype, kidney donor profile index, graft cold ischemia time, phenylephrine dose, and dopamine dose were associated with DGF. After multivariable analysis, increased donor serum creatinine, donor age, kidney donor profile index, graft cold ischemia time, and phenylephrine dose remained independent predictors of DGF.

CONCLUSION

Higher doses of phenylephrine were an independent predictor of DGF. With the exception of phenylephrine, the selection and dose of vasopressor during donor management did not predict the development of DGF.

LEVEL OF EVIDENCE

Prognostic study, Level III.

17β-Estradiol as a New Therapy to Preserve Microcirculatory Perfusion in Small Bowel Donors

BACKGROUND

Intestine graft viability compromises retrieval in most brain-dead donors. Small bowel transplantation is a complex procedure with worse outcomes than transplantation of other abdominal organs. The hormone 17β-estradiol (E2) has shown vascular protective effects in lung tissue of brain death (BD) male rats. Thus, estradiol might be a treatment option to improve the quality of intestinal grafts.

METHODS

Male Wistar rats were divided into 3 groups (n = 10/group): rats that were trepanned only (sham-operated), rats subjected to rapid-onset BD, and brain-dead rats treated with E2 (280 µg/kg, intravenous) (BD-E2). Experiments performed for 180 minutes thereafter are included: (a) laser-Doppler flowmetry and intravital microscopy to evaluate mesenteric perfusion; (b) histopathological analysis; (c) real-time polymerase chain reaction of endothelial nitric oxide synthase (eNOS) and endothelin-1; (d) immunohistochemistry of eNOS, endothelin-1, P-selectin, intercellular adhesion molecule 1, and vascular cell adhesion molecule 1 expression; and (e) ELISA for cytokines and chemokines measurement.

RESULTS

17β-Estradiol improved microcirculatory perfusion and reduced intestinal edema and hemorrhage after BD. The proportions of perfused small vessels were (mean ± scanning electron microscope) BD rats (40% ± 6%), sham-operated rats (75% ± 8%), and BD-E2 rats (67% ± 5%) (P = 0.011). 17β-Estradiol treatment was associated with 2-fold increase in eNOS protein (P < 0.0001) and gene (P = 0.0009) expression, with no differences in endothelin-1 expression. BD-E2 rats exhibited a reduction in vascular cell adhesion molecule 1 expression and reduced cytokine-induced neutrophil chemoattractant 1 and interleukina-10 serum levels.

CONCLUSIONS

17β-Estradiol was effective in improving mesenteric perfusion and reducing intestinal edema and hemorrhage associated with BD. The suggestion is that E2 might be considered a therapy to mitigate, at least in part, the deleterious effects of BD in small bowel donors.

Anesthetic Considerations in Facial Transplantation: Experience at NYU Langone Health and Systematic Review

Anesthetic considerations are integral to the success of facial transplantation (FT), yet limited evidence exists to guide quality improvement. This study presents an institutional anesthesia protocol, defines reported anesthetic considerations, and provides a comprehensive update to inform future directions of the field.

Point-of-care blood gas analyzers have an impact on the acceptance of donor lungs for transplantation

An organ donor PaO2 above 40 kPa is generally required for lung transplantation. Point-of-care (POC) blood gas analyzers are commonly used by organ procurement organizations (OPO) but may underestimate the PaO2 at high levels. We hypothesized that changing to a more accurate blood gas analyzer would result in additional lungs transplanted. All PaO2 measurements on organ donors managed at one OPO's recovery center were performed on an i-STAT POC analyzer prior to October 2015, and on a GEM 4000 subsequently. For 24 weeks, all blood gases were tested simultaneously on both analyzers. We compared lung outcomes of 147 donors in the year prior to this change (using the i-STAT) with 56 donors in the 24-week study period (using the GEM 4000 for lung allocation). When the PaO2 was above 40 kPa, the i-STAT PaO2 was 7.2 kPa lower on average than the GEM 4000. When the GEM PaO2 measured between 40 and 50 kPa, the corresponding i-STAT PaO2 value registered less than 40 kPa 25 out of 48 times (52%), with an average difference of 7.3 kPa (SD = 2.9). The rate of lungs transplanted using the GEM 4000 was 48% compared with 35% in the year prior using the i-STAT (p = .11), with equivalent recipient outcomes. The i-STAT analyzer underestimated the PaO2 above 40 kPa and changing to a more accurate PaO2 analyzer may increase lungs transplanted.

Development of a Pulmonary Workshop for Organ Recovery Coordinators' Continuing Medical Education

Organ recovery coordinators (ORCs) have varied professional education backgrounds; however, based on their specialized education, their training may not have included in-depth mechanical ventilation and pulmonary management. An 8-hour pulmonary workshop was developed in collaboration between an organ procurement organization and a university-based respiratory care department. The workshop focused on pulmonary management and hands-on laboratory exercises using mechanical ventilators. A program assessment questionnaire was completed by participants following the workshop, which requested their self-reported comfort/familiarity with pulmonary management skills before and after the workshop on a 5-point Likert scale. Following the pulmonary workshop, the mean ORC comfort/familiarity for all pulmonary management skills increased significantly (P < .01). This program suggests ORCs can develop a greater awareness and comfort with pulmonary management by participating in a continuing education pulmonary workshop. Continuing education initiatives focused on pulmonary management of donor patients using hands-on competencies should be part of the ORCs practice improvement efforts.

For Victims of Fatal Child Abuse, Who Has the Right to Consent to Organ Donation?

In rare circumstances, children who have suffered traumatic brain injury from child abuse are declared dead by neurologic criteria and are eligible to donate organs. When the parents are the suspected abusers, there can be confusion about who has the legal right to authorize organ donation. Furthermore, organ donation may interfere with the collection of forensic evidence that is necessary to evaluate the abuse. Under those circumstances, particularly in the context of a child homicide investigation, the goals of organ donation and collection and preservation of critical forensic evidence may seem mutually exclusive. In this Ethics Rounds, we discuss such a case and suggest ways to resolve the apparent conflicts between the desire to procure organs for donation and the need to thoroughly evaluate the evidence of abuse.

Vasopressor Therapy in the Intensive Care Unit

After fluid administration for vasodilatory shock, vasopressors are commonly infused. Causes of vasodilatory shock include septic shock, post-cardiovascular surgery, post-acute myocardial infarction, postsurgery, other causes of an intense systemic inflammatory response, and drug -associated anaphylaxis. Therapeutic vasopressors are hormones that activate receptors-adrenergic: α1, α2, β1, β2; angiotensin II: AG1, AG2; vasopressin: AVPR1a, AVPR1B, AVPR2; dopamine: DA1, DA2. Vasopressor choice and dose vary widely because of patient and physician practice heterogeneity. Vasopressor adverse effects are excessive vasoconstriction causing organ ischemia/infarction, hyperglycemia, hyperlactatemia, tachycardia, and tachyarrhythmias. To date, no randomized controlled trial (RCT) of vasopressors has shown a decreased 28-day mortality rate. There is a need for evidence regarding alternative vasopressors as first-line vasopressors. We emphasize that vasopressors should be administered simultaneously with fluid replacement to prevent and decrease duration of hypotension in shock with vasodilation. Norepinephrine is the first-choice vasopressor in septic and vasodilatory shock. Interventions that decrease norepinephrine dose (vasopressin, angiotensin II) have not decreased 28-day mortality significantly. In patients not responsive to norepinephrine, vasopressin or epinephrine may be added. Angiotensin II may be useful for rapid resuscitation of profoundly hypotensive patients. Inotropic agent(s) (e.g., dobutamine) may be needed if vasopressors decrease ventricular contractility. Dopamine has fallen to almost no-use recommendation because of adverse effects; angiotensin II is available clinically; there are potent vasopressors with scant literature (e.g., methylene blue); and the novel V1a agonist selepressin missed on its pivotal RCT primary outcome. In pediatric septic shock, vasopressors, epinephrine, and norepinephrine are recommended equally because there is no clear evidence that supports the use of one vasoactive agent. Dopamine is recommended when epinephrine or norepinephrine is not available. New strategies include perhaps patients will be started on several vasopressors with complementary mechanisms of action, patients may be selected for particular vasopressors according to predictive biomarkers, and novel vasopressors may emerge with fewer adverse effects.

Variability in deceased donor care in Canada: a report of the Canada-DONATE cohort study

PURPOSE

Canadian donor management practices have not been reported. Our aim was to inform clinicians and other stakeholders about the range of current practices.

METHODS

This prospective observational cohort study enrolled consecutive, newly consented organ donors from August 1 2015 to July 31 2018 at 27 academic and five community adult intensive care units in British Columbia, Alberta, Ontario, and Quebec. Research staff prospectively recorded donor management data. Provincial organ donation organizations verified the organs donated. We formally compared practices across provinces.

RESULTS

Over a median collection period of eight months, 622 potential donors were classified at baseline as having neurologic determination of death (NDD donors; n = 403) or circulatory death (DCD donors; n = 219). Among NDD donors, 85.6% underwent apnea testing (rarely with carbon dioxide insufflation), 33.2% underwent ancillary testing, and subsequent therapeutic hypothermia (34-35°C) was rare. Neurologic determination of death donors were more hemodynamically unstable with most having received vasopressin and norepinephrine infusions, with a large majority having received high-dose corticosteroids and intravenous thyroxine. Among DCD donors, 61.6% received corticosteroids, and 8.9% received thyroxine. Most donors did not receive lung-protective ventilation strategies. Invasive procedures after donation consent included bronchoscopy (71.7%), cardiac catheterization (NDD donors only; 21.3%), and blood transfusions (19.3%). Physicians ordered intravenous antemortem heparin for 94.8% of DCD donors. The cohort donated 1,629 organs resulting in 1,532 transplants. Case selection, death determinations, and hormone, nutrition and heparin practices all varied across provinces.

CONCLUSION

These study findings highlight areas for knowledge translation and further clinical research. Interprovincial discrepancies will likely pose unique challenges to national randomized trials.

TRIAL REGISTRATION

www.clinicaltrials.gov (NCT03114436); registered 10 April, 2017.

Is informed consent required for the diagnosis of brain death regardless of consent for organ donation?

In the half-century history of clinical practice of diagnosing brain death, informed consent has seldom been considered until very recently. Like many other medical diagnoses and ordinary death pronouncements, it has been taken for granted for decades that brain death is diagnosed and death is declared without consideration of the patient's advance directives or family's wishes. This essay examines the pros and cons of using informed consent before the diagnosis of brain death from an ethical point of view. As shared decision-making in clinical practice became increasingly indispensable, respect for the patients' autonomous wishes regarding how to end their lives has a significant role in deciding how death is diagnosed. Brain death, as a fully technologically controlled death, may require a different ethical framework from the old one for traditional cardiac death. With emerging and proliferating options in end-of-life care for those who suffer from catastrophic brain injury, the traditional reasoning that 'death gives no choice, hence no consent' requires another examination. Patients facing imminent brain death now have options other than undergoing the diagnostic workup for brain death, such as donation after circulatory death and withdrawal of life-sustaining treatment with maximum comfort measures for death with dignity. Nevertheless, just as in the debate over opt-in versus opt-out organ donation policies, informed consent before the diagnosis of brain death faces fierce opposition from consequentialists urging the expansion of the donor pool. This essay examines these objections and provides constructive replies along with a proposal to accommodate this morally required consent.

A Randomized Controlled Trial of Naloxone for Optimization of Hypoxemia in Lung Donors After Brain Death

BACKGROUND

Persistent hypoxemia is the principal reason lungs from otherwise eligible brain dead (BD) organ donors are not transplanted. Experimental models and retrospective studies have suggested that naloxone attenuates neurogenic pulmonary edema and reverses hypoxemia after brain death. We undertook a multisite, randomized, placebo-controlled trial to evaluate whether naloxone is able to improve oxygenation in BD donors with hypoxemia.

METHODS

BD organ donors at 4 organ procurement organizations were randomized in a blinded manner to naloxone 8 mg or saline placebo if lung were being considered for allocation but exhibited hypoxemia (partial pressure of oxygen in arterial blood to fraction of inspired oxygen ratio [PFR] below 300 mm Hg). The primary outcome was change in PFR from baseline to final arterial blood gas. Secondary outcomes included early improvement in PFR and proportion of lungs transplanted.

RESULTS

A total of 199 lung-eligible BD donors were randomized to naloxone (n = 98) or placebo (n = 101). Groups were comparable at baseline. Both groups exhibited similar improvements in oxygenation (median improvement in PFR of 81 with naloxone versus 80 with saline, P = 0.68), with 37 (39%) versus 38 (40%) exhibiting reversal of hypoxemia. There was no difference in the rate of lungs transplanted (19% in both groups, P = 0.97) although it was significantly higher in those with reversal of hypoxemia (32/69 versus 2/111, P < 0.001).

CONCLUSIONS

Naloxone does not improve oxygenation more than placebo in hypoxemic organ donors. However, reversal of hypoxemia was a powerful predictor of lung utilization regardless of drug therapy. Further organ procurement organization-led research is needed to assess optimal interventions to improve oxygenation in BD donors with hypoxemia.

Structure and function of a trauma intensive care unit: A report from the Trauma Intensive Care Unit Prevalence Project

BACKGROUND

Specialized trauma intensive care unit (TICU) care impacts patient outcomes. Few studies describe where and how TICU care is delivered. We performed an assessment of TICU structure and function at a sample of US trauma center TICUs.

METHODS

This was a multicenter study in which participants supplied information about their trauma centers, staff, clinical protocols, processes of care, and study TICU (the ICU admitting the majority of trauma patients).

RESULTS

Forty-five Level I trauma centers trauma centers enrolled through the American Association for the Surgery of Trauma multi-institutional trials platform; 71.1% had less than 750 beds and 55.5% treated 1,000 to 2,999 trauma activations/year. The median number of hospital ICU beds was 109 [66-185]. 46.7% were "closed" ICUs, 20% were "open," and 82.2% had mandatory intensivist consultation. 42.2% ICUs were classified as trauma (≥80% of patients were trauma), 46.7% surgical/trauma, and 11.1% medical-surgical. Trauma ICUs had a median 10 [7-12] intensivists. Intensivists were present 24 hours/day in 80% of TICUs. Centers reported a median of 8 (interquartile range [IQR], 6-10) full-time trauma surgeons, whose ICU duties comprised 25% (IQR, 20%-40%) of their clinical time and 20% (IQR, 20-33) of total work time. A median 16 (IQR, 12-23) ICU beds in use were staffed by 10 (IQR, 7-14) nurses. There was considerable variation in the number and type of protocols used and in diagnostic methods for ventilator-associated pneumonia. Daily patient care checklists were used by 80% of ICUs. While inclusion of families on rounds was performed in 91.1% of ICUs, patient- and family-centered support programs were less common.

CONCLUSION

A study of structure and function of TICUs at a sample of Level I trauma centers revealed that presence of nontrauma patients was common, critical care is a significant component of trauma surgeons' professional practice, and significant variation exists in care delivery models and protocol use. Opportunities may exist to improve care through sharing of best practices.

LEVEL OF EVIDENCE

Therapeutic/Care management, level IV.

Suboptimal Donors Do Not Mean Worse Results: A Single-Center Study of Extending Donor Criteria for Lung Transplant

BACKGROUND

Lung transplant remains the only viable treatment for most of the end-stage lung diseases. It is believed that extending criteria for donor lungs would increase the number of lung transplants. The aim of the study was to compare the graft function by means of oxygenation index among recipients who received the lungs from donors of extended criteria with those whose received lungs from donors who met the standard criteria.

METHODS

This retrospective study analyzed 71 donors whose lungs where transplanted into 71 first-time double lung recipients of 2 groups: patients who received transplants before and after 2018. The objective was to assess whether there is a significant difference in quality of the donor pool after applying extended criteria. The second objective was to compare results of recipients with lungs from donors of oxygenation index > 400 mm Hg with those obtained among recipients with this parameter < 400 mm Hg.

RESULTS

In the case of transplants performed in 2018 to 2019, oxygenation indices were significantly lower in donors but significantly higher in recipients on the first day than those observed in 2015 to 2017. The number of transplants increased from 9 per year to 22 per year. Irrespective of whether the donor had PaO₂/fraction of inspired oxygen above or below 400 mm Hg, recipients showed similar oxygenation index values after transplant (mean oxygenation index, 462 vs 412 mm Hg, respectively). Short-term mortality did not differ either.

CONCLUSIONS

Extended criteria of lungs suitability as a potential grafts not only increases the donor pool but also proves that suboptimal donors are not associated with producing inferior results of the recipients.

Optimisation of the organ donor and effects on transplanted organs: a narrative review on current practice and future directions

Mortality remains high for patients on the waiting list for organ transplantation. A marked imbalance between the number of available organs and recipients that need to be transplanted persists. Organs from deceased donors are often declined due to perceived and actual suboptimal quality. Adequate donor management offers an opportunity to reduce organ injury and maximise the number of organs than can be offered in order to respect the donor's altruistic gift. The cornerstones of management include: correction of hypovolaemia; maintenance of organ perfusion; prompt treatment of diabetes insipidus; corticosteroid therapy; and lung protective ventilation. The interventions used to deliver these goals are largely based on pathophysiological rationale or extrapolations from general critical care patients. There is currently insufficient high-quality evidence that has assessed whether any interventions in the donor after brain death may actually improve immediate post-transplant function and long-term graft survival or recipient survival after transplantation. Improvements in our understanding of the underlying mechanisms following brain death, in particular the role of immunological and metabolic changes in donors, offer promising future therapeutic opportunities to increase organ utilisation. Establishing a UK donor management research programme involves consideration of ethical, logistical and legal issues that will benefit transplanted patients while respecting the wishes of donors and their families.