The effect of steroid pretreatment of deceased organ donors on liver allograft function: a blinded randomized placebo-controlled trial

Guidelines for the Management of Adult Acute and Acute-on-Chronic Liver Failure in the ICU: Neurology, Peri-Transplant Medicine, Infectious Disease, and Gastroenterology Considerations

OBJECTIVES

To develop evidence-based recommendations for clinicians caring for adults with acute liver failure (ALF) or acute on chronic liver failure (ACLF) in the ICU.

DESIGN

The guideline panel comprised 27 members with expertise in aspects of care of the critically ill patient with liver failure or methodology. We adhered to the Society of Critical Care Medicine standard operating procedures manual and conflict-of-interest policy. Teleconferences and electronic-based discussion among the panel, as well as within subgroups, served as an integral part of the guideline development.

INTERVENTIONS

In part 2 of this guideline, the panel was divided into four subgroups: neurology, peri-transplant, infectious diseases, and gastrointestinal groups. We developed and selected Population, Intervention, Comparison, and Outcomes (PICO) questions according to importance to patients and practicing clinicians. For each PICO question, we conducted a systematic review and meta-analysis where applicable. The quality of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation approach. We used the evidence to decision framework to facilitate recommendations formulation as strong or conditional. We followed strict criteria to formulate best practice statements.

MEASUREMENTS AND MAIN RESULTS

We report 28 recommendations (from 31 PICO questions) on the management ALF and ACLF in the ICU. Overall, five were strong recommendations, 21 were conditional recommendations, two were best-practice statements, and we were unable to issue a recommendation for five questions due to insufficient evidence.

CONCLUSIONS

Multidisciplinary, international experts formulated evidence-based recommendations for the management ALF and ACLF patients in the ICU, acknowledging that most recommendations were based on low quality and indirect evidence.

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.

Steroid pretreatment of deceased donors and liver allograft function - Ten years follow-up of a blinded randomized placebo controlled trial

BACKGROUND

Within the last decade numerous attempts have been reported in order to expand the donor pool and alleviate organ shortage in the setting of liver transplantation. Aim of this blinded randomized controlled trial was to evaluate the effect of donor steroid pretreatment on outcomes after liver transplantation.

METHODS

We performed an international, multi-center double-blinded randomized placebo controlled trial. Donors received 1000 mg methylprednisone or placebo before organ procurement. Primary endpoint were patient and graft survival. Secondary end points were rate of BPAR and liver functions trajectories after transplantation. Follow up was 10 years.

RESULTS

There was no effect of steroid pretreatment vs. placebo on overall patient survival (50% vs. 46%, p = n.s.) as well as graft survival (47% vs. 51%, p= n.s.). Further donor steroid pretreatment did not alter the rate of biopsy proven acute rejections (34% steroid group vs. 36% placebo, p = n.s.). Evaluating short term and long term graft function, steroid pretreatment had minor effect on immediate liver function trajectories within the first 2 weeks after transplantation. This was not seen in long-term follow up.

CONCLUSION

In conclusion we found no evidence that donor steroid pretreatment translates in improved outcomes after liver transplantation.

Outcome measures in solid organ donor management research: a systematic review

AIM

We systematically reviewed published outcome measures across randomised controlled trials (RCTs) of donor management interventions.

METHODS

The systematic review was conducted in accordance with recommendations by the Cochrane Handbook and Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. We searched MEDLINE, Embase, CENTRAL, Web of Science, and trial databases from 1980 to February 2021 for RCTs of donor management interventions.

RESULTS

Twenty-two RCTs (n=3432 donors) were included in our analysis. Fourteen RCTs (63.6%) reported a primary outcome relating to a single organ only. Eight RCTs primarily focused on aspects of donor optimisation in critical care. Thyroid hormones and methylprednisolone were the most commonly evaluated interventions (five and four studies, respectively). Only two studies, focusing on single organs (e.g. kidney), evaluated outcomes relating to other organs. The majority of studies evaluated physiological or biomarker-related outcomes. No study evaluated recipient health-related quality of life. Only one study sought consent from potential organ recipients.

CONCLUSIONS

The majority of RCTs evaluating donor management interventions only assessed single-organ outcomes or effects on donor stability in critical care. There is a need for an evaluation of patient-centred recipient outcomes and standardisation and reporting of outcome measures for future donor management RCTs.

The Human Immune Response to Cadaveric and Living Donor Liver Allografts

The liver is an important contributor to the human immune system and it plays a pivotal role in the creation of both immunoreactive and tolerogenic conditions. Liver transplantation provides the best chance of survival for both children and adults with liver failure or cancer. With current demand exceeding the number of transplantable livers from donors following brain death, improved knowledge, technical advances and the desire to prevent avoidable deaths has led to the transplantation of organs from living, ABO incompatible (ABOi), cardiac death donors and machine based organ preservation with acceptable results. The liver graft is the most well-tolerated, from an immunological perspective, of all solid organ transplants. Evidence suggests successful cessation of immunosuppression is possible in ~20–40% of liver transplant recipients without immune mediated graft injury, a state known as “operational tolerance.” An immunosuppression free future following liver transplantation is an ambitious but perhaps not unachievable goal. The initial immune response following transplantation is a sterile inflammatory process mediated by the innate system and the mechanisms relate to the preservation-reperfusion process. The severity of this injury is influenced by graft factors and can have significant consequences. There are minimal experimental studies that delineate the differences in the adaptive immune response to the various forms of liver allograft. Apart from ABOi transplants, antibody mediated hyperacute rejection is rare following liver transplant. T-cell mediated rejection is common following liver transplantation and its incidence does not differ between living or deceased donor grafts. Transplantation in the first year of life results in a higher rate of operational tolerance, possibly due to a bias toward Th2 cytokines (IL4, IL10) during this period. This review further describes the current understanding of the immunological response toward liver allografts and highlight the areas of this topic yet to be fully understood.

Management of the Pediatric Organ Donor

Management of the pediatric organ donor necessitates understanding the physiologic changes that occur preceding and after death determination. Recognizing these changes allows application of the therapeutic strategies designed to optimize hemodynamics and metabolic state to allow for preservation of end-organ function for maximal organ recovery and minimal damage to the donor grafts. The pediatric pharmacist serves as the medication expert and may collaborate with the organ procurement organizations for provision of pharmacologic hemodynamic support, hormone replacement therapy, antimicrobials, and nutrition for the pediatric organ donor.

Steroid pretreatment of organ donors does not impact on early rejection and long-term kidney allograft survival: Results from a multicenter randomized, controlled trial

Steroid pretreatment of deceased donors reduces inflammation in allografts and is recommended by organ procurement guidelines. The impact on long-term graft outcome, however, remains elusive. In this multicenter randomized controlled trial, 306 deceased donors providing organs for 455 renal transplant recipients were randomized to 1000 mg of methylprednisolone or placebo prior to organ procurement (ISRCTN78828338). The incidence of biopsy-confirmed rejection (Banff>1) at 3 months was 23 (10%) in the steroid group and 26 (12%) in the placebo group (P = .468). Five-year functional graft survival was 84% and 82% for the steroid group and placebo group, respectively (P-value = .941). The hazard ratio of functional graft loss was 0.90 (95% confidence interval 0.57-1.42, P = .638) for steroid vs placebo in a multivariate Cox model. We did not observe effect modification by any of the predictors of graft survival and treatment modality. A robust sandwich estimate was used to account for paired grafts of some donors. The mean estimated GFR at 5 years was 47 mL/min per 1.73 m² in the steroid group and 48 mL/min per 1.73 m² in the placebo group (P = .756). We conclude that steroid pretreatment does not impact on long-term graft survival. In a donor population with higher risk of delayed graft function, however, repetitive and higher doses of steroid treatment may result in different findings.

Efficacy and Safety of Steroid Therapy for Posttransplant Hyperbilirubinemia Caused by Early Allograft Dysfunction: A Randomized Controlled Trial

BACKGROUND Hyperbilirubinemia is a common event that occurs after liver transplantation. Hyperbilirubinemia is usually caused by early allograft dysfunction. Glucocorticoid is widely used for immunosuppression, but few studies have analyzed the effects of steroid therapy on posttransplantation hyperbilirubinemia. The aim of this study was to assess whether glucocorticoid was beneficial in treating hyperbilirubinemia caused by early allograft dysfunction. MATERIAL AND METHODS Patients with postoperative hyperbilirubinemia (those with conditions such as biliary complications and rejections were excluded) were randomly assigned, in a 2: 1 ratio, to the steroid and control groups. Patients in the steroid group were treated with glucocorticoid combined with ursodeoxycholic acid, whereas patients in the control group were only treated with ursodeoxycholic acid. The primary endpoint was decrease in bilirubin and the secondary endpoint was safety. RESULTS From 1st June 2016 to 30th April 2018, 40 patients were enrolled into the steroid group, and 20 were enrolled into the control group. Donor, recipient, and operative data were similar between the 2 groups. The decrease in bilirubin levels in the steroid group was significantly greater than that in the control group on the first day after the intervention was finished (9.25±1.30 mg/dL vs. 3.11±1.45 mg/dL, p=0.005), and after 2 weeks (15.01±1.20 mg/dL vs. 8.88±1.98 mg/dL, p=0.007). The steroid group did not have a higher complication rate but it did have a shorter postoperative hospital stay than in the control group. CONCLUSIONS Low-dose steroid therapy was effective and safe for treating hyperbilirubinemia caused by early graft dysfunction, and it improved liver function.

Effect of Methylprednisolone on Liver Injury and Endotoxin Levels Following Brain Death in Rats

BACKGROUND AND AIM

Brain death impairs liver function in potential donors and is associated with inflammatory activation. Methylprednisolone treatment after brain death has been shown to reduce inflammatory activity. The aim of the present study was to evaluate the effects of methylprednisolone on liver injury and endotoxin levels in brain-dead rats.

METHODS

Thirty-two rats were randomly divided into 4 groups: a sham-operation group (Sham group), a brain death with methylprednisolone treatment group (Methy group), a brain death with saline treatment group (Saline group), and a brain death group (BD group). The rats were anesthetized and induced by gradually increasing the intra-cranial pressure using a Fogarty catheter balloon for brain death. All of the animals were observed and ventilated for 6 h prior to being euthanized. Hepatic pathologic histology (Knodell histology activity index), liver inflammatory cytokine levels, liver function and endotoxin levels were assessed.

RESULTS

After brain death, methylprednisolone markedly alleviated the Knodell histology activity index of liver injury (P < .05). Additionally, significant reductions in the levels of TNF-α, IL-1β, and IL-10 were observed in the Methy group compared to those in the Saline and BD groups (P < .01), whereas no significant differences were found between the Saline and BD groups (P > .05). Interestingly, although the rate of liver injury after brain death in the methylprednisolone treatment group improved, the endotoxin level did not decline in the Methy group compared to the levels in the Saline and BD groups (P > .05).

CONCLUSION

The present study verified that methylprednisolone was protective for liver injury in rats subjected to brain death. This protection appeared to be due to reduced inflammatory activity with no influence on the endotoxin level.

Control of Ischemia-Reperfusion Injury in Liver Transplantation: Potentials for Increasing the Donor Pool

Background

Organ shortage is a growing problem, with a rising number of organs being harvested from extended criteria donors, and this trend will further continue to increase as organ donors are getting older and have more comorbidities. Since this fact is immutable, efforts have been made to reduce the extent of ischemia-reperfusion injury (IRI) as well as of direct and indirect harvest-related graft injury which affects all organs in a more or less distinct way.

Methods

In liver transplantation (LT), the activation of Kupffer cells during organ reperfusion, thus provoking microcirculatory disturbances, hypoxia, and endothelial cell injury, is one of the key mechanisms causing graft dysfunction. Multiple approaches have been taken in order to find efficient preconditioning methods by pharmacological pretreatment, controlled induction of ischemia, controlled denervation of donor organs, and reconditioning with machine perfusion to prevent IRI, whereas marginal organs (i.e. steatotic grafts) are especially vulnerable.

Results

The above-mentioned approaches have been pursued in experimental and clinical settings. At this time point, however, there is not yet enough clinical evidence available to recommend any particular drug pretreatment or any other intervention for organ preconditioning prior to transplantation.

Conclusion

The multifactorial pathophysiology in the setting of IRI in LT requires a multimodal therapeutic approach with the integration of pharmacological and technical means being applied to the donor, the organ per se, and the recipient. Currently, there is no consensus on standardized pretreatment of donor organs in order to improve the transplant outcome.

Graft Pre-conditioning by Peri-Operative Perfusion of Kidney Allografts With Rabbit Anti-human T-lymphocyte Globulin Results in Improved Kidney Graft Function in the Early Post-transplantation Period-a Prospective, Randomized Placebo-Controlled Trial

Introduction: Although prone to a higher degree of ischemia reperfusion injury (IRI), the use of extended criteria donor (ECD) organs has become reality in transplantation. We therefore postulated that peri-operative perfusion of renal transplants with anti-human T-lymphocyte globulin (ATLG) ameliorates IRI and results in improved graft function.

Methods: We performed a randomized, single-blinded, placebo-controlled trial involving 50 kidneys (KTx). Prior to implantation organs were perfused and incubated with ATLG (AP) (n = 24 kidney). Control organs (CP) were perfused with saline only (n = 26 kidney). Primary endpoint was defined as graft function reflected by serum creatinine at day 7 post transplantation (post-tx).

Results: AP-KTx recipients illustrated significantly better graft function at day 7 post-tx as reflected by lower creatinine levels, whereas no treatment effect was observed after 12 months surveillance. During the early hospitalization phase, 16 of the 26 CP-KTx patients required dialysis during the first 7 days post-tx, whereas only 10 of the 24 AP-KTx patients underwent dialysis. No treatment-specific differences were detected for various lymphocytes subsets in the peripheral blood of patients. Additionally, mRNA analysis of 0-h biopsies post incubation with ATLG revealed no changes of intragraft inflammatory expression patterns between AP and CP organs.

Conclusion: We here present the first clinical study on peri-operative organ perfusion with ATLG illustrating improved graft function in the early period post kidney transplantation.

Clinical Trial Registration:www.ClinicalTrials.gov, NCT03377283

Systematic review on the treatment of deceased organ donors

BACKGROUND

Currently, there is no consensus on which treatments should be a part of standard deceased-donor management to improve graft quality and transplantation outcomes. The objective of this systematic review was to evaluate the effects of treatments of the deceased, solid-organ donor on graft function and survival after transplantation.

METHODS

Pubmed, Embase, Cochrane, and Clinicaltrials.gov were systematically searched for randomized controlled trials that compared deceased-donor treatment versus placebo or no treatment.

RESULTS

A total of 33 studies were selected for this systematic review. Eleven studies were included for meta-analyses on three different treatment strategies. The meta-analysis on methylprednisolone treatment in liver donors (two studies, 183 participants) showed no effect of the treatment on rates of acute rejection. The meta-analysis on antidiuretic hormone treatment in kidney donors (two studies, 222 participants) indicates no benefit in the prevention of delayed graft function. The remaining meta-analyses (seven studies, 334 participants) compared the effects of 10 min of ischaemic preconditioning on outcomes after liver transplantation and showed that ischaemic preconditioning improved short-term liver function, but not long-term transplant outcomes.

CONCLUSIONS

There is currently insufficient evidence to conclude that any particular drug treatment or any intervention in the deceased donor improves long-term graft or patient survival after transplantation.

Guidelines for the management of a brain death donor in the rhesus macaque: A translational transplant model

Introduction

The development of a translatable brain death animal model has significant potential to advance not only transplant research, but also the understanding of the pathophysiologic changes that occur in brain death and severe traumatic brain injury. The aim of this paper is to describe a rhesus macaque model of brain death designed to simulate the average time and medical management described in the human literature.

Methods

Following approval by the Institutional Animal Care and Use Committee, a brain death model was developed. Non-human primates were monitored and maintained for 20 hours after brain death induction. Vasoactive agents and fluid boluses were administered to maintain hemodynamic stability. Endocrine derangements, particularly diabetes insipidus, were aggressively managed.

Results

A total of 9 rhesus macaque animals were included in the study. The expected hemodynamic instability of brain death in a rostral to caudal fashion was documented in terms of blood pressure and heart rate changes. During the maintenance phase of brain death, the animal’s temperature and hemodynamics were maintained with goals of mean arterial pressure greater than 60mmHg and heart rate within 20 beats per minute of baseline. Resuscitation protocols are described so that future investigators may reproduce this model.

Conclusion

We have developed a reproducible large animal primate model of brain death which simulates clinical scenarios and treatment. Our model offers the opportunity for researchers to have translational model to test the efficacy of therapeutic strategies prior to human clinical trials.

Understanding the effect of corticosteroid pretreatment in brain-dead organ donors: new mechanistic insights for improvement of organ quality in liver transplantation

Transplant surgeons are currently faced with the challenge to accept marginal liver transplants due to steatosis or old age. Improving organ quality by implementing a selective organ protective donor management could be the first step towards a graft of enhanced quality. However, the molecular mechanisms of such treatments are still poorly understood. Glucocorticoid medication in donor medicine has been carried out and discussed for a long time. In a recent study published in Clinical Science, Jiménez-Castro et al. [Clin. Sci. (2017) 131, 733-746] demonstrate how liver histology and transplant liver function can be improved by administration of glucocorticoids to brain-dead donor rats with steatotic livers. This work illustrates the need for further trials in order to selectively improve the quality of steatotic livers with a potential for liver transplantation.

Effect of corticosteroid administration on neurologically deceased organ donors and transplant recipients: a systematic review and meta-analysis

OBJECTIVES

This review investigates the impact of corticosteroids on donation rates and transplant outcomes in light of findings from randomised controlled trials (RCTs) and to highlight the sources of uncertainty in this unresolved donor management issue.

DATA SOURCES

We searched electronic databases, trial registries and conference proceedings for RCTs evaluating corticosteroid therapy in neurologically deceased donors.

STUDY SELECTION AND DATA EXTRACTION

Independent reviewers assessed eligibility, evaluated risk of bias and abstracted data, including donor haemodynamic data, number of organs recovered and transplant outcomes. Where possible, we pooled results. For each outcome, we assessed the overall quality of evidence using The Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology.

DATA SYNTHESIS

Eleven RCTs with different corticosteroid regimens were included. Most trials assessed a once-daily infusion of methylprednisolone. Aside from one study showing improved liver graft function, no individual study or pooled analysis showed benefit of corticosteroids for any outcome: vasopressor use (three trials; relative risk (RR) 0.96; 95% CI 0.89 to 1.05), multiple organs recovered (two trials; RR 0.82; 95% CI 0.61 to 1.11), acute graft rejection (three trials; RR 0.91; 95% CI 0.60 to 1.39) or graft dysfunction (eight trials; RR 1.01; 95% CI 0.83 to 1.24). Two trials investigated adverse effects and found similar rates between groups. Quality of evidence was moderate or low for all outcomes.

CONCLUSION

Current clinical trials are limited in numbers and size to identify benefits or harms of corticosteroid therapy for deceased organ donors. In the face of these results, administering or withholding steroids both appear reasonable courses of action.

Biomarkers in renal transplantation: An updated review

Genomics, proteomics and molecular biology lead to tremendous advances in all fields of medical sciences. Among these the finding of biomarkers as non invasive indicators of biologic processes represents a useful tool in the field of transplantation. In addition to define the principal characteristics of the biomarkers, this review will examine the biomarker usefulness in the different clinical phases following renal transplantation. Biomarkers of ischemia-reperfusion injury and of delayed graft function are extremely important for an early diagnosis of these complications and for optimizing the treatment. Biomarkers predicting or diagnosing acute rejection either cell-mediated or antibody-mediated allow a risk stratification of the recipient, a prompt diagnosis in an early phase when the histology is still unremarkable. The kidney solid organ response test detects renal transplant recipients at high risk for acute rejection with a very high sensitivity and is also able to make diagnosis of subclinical acute rejection. Other biomarkers are able to detect chronic allograft dysfunction in an early phase and to differentiate the true chronic rejection from other forms of chronic allograft nephropathies no immune related. Finally biomarkers recently discovered identify patients tolerant or almost tolerant. This fact allows to safely reduce or withdrawn the immunosuppressive therapy.

Organ donor management: Eight common recommendations and actions that deserve reflection

Despite major advances in our understanding of the physiopathology of brain death (BD), there are important controversies as to which protocol is the most appropriate for organ donor management. Many recent reviews on this subject offer recommendations that are sometimes contradictory and in some cases are not applied to other critically ill patients. This article offers a review of the publications (many of them recent) with an impact upon these controversial measures and which can help to confirm, refute or open new areas of research into the most appropriate measures for the management of organ donors in BD, and which should contribute to discard certain established recommendations based on preconceived ideas, that lead to actions lacking a physiopathological basis. Aspects such as catecholamine storm management, use of vasoactive drugs, hemodynamic objectives and monitoring, assessment of the heart for donation, and general care of the donor in BD are reviewed.

Impact of Donation Mode on the Proportion and Function of T Lymphocytes in the Liver

BACKGROUND

Liver T-cells respond to the inflammatory insult generated during organ procurement and contribute to the injury following reperfusion. The mode of liver donation alters various metabolic and inflammatory pathways but the way it affects intrahepatic T-cells is still unclear.

METHODS

We investigated the modifications occurring in the proportion and function of T-cells during liver procurement for transplantation. We isolated hepatic mononuclear cells (HMC) from liver perfusate of living donors (LD) and donors after brain death (DBD) or cardiac death (DCD) and assessed the frequency of T-cell subsets, their cytokine secretion profile and CD8 T-cell cytotoxicity function, responsiveness to a danger associated molecular pattern (High Mobility Group Box1, HMGB1) and association with donor and recipient clinical parameters and immediate graft outcome.

RESULTS

We found that T-cells in healthy human livers were enriched in memory CD8 T-cells exhibiting a phenotype of non-circulating tissue-associated lymphocytes, functionally dominated by more cytotoxicity and IFN-γ-production in DBD donors, including upon activation by HMGB1 and correlating with peak of post-transplant AST. This liver-specific pattern of CD8 T-cell was prominent in DBD livers compared to DCD and LD livers suggesting that it was influenced by events surrounding brain death, prior to retrieval.

CONCLUSION

Mode of liver donation can affect liver T-cells with increased liver damage in DBD donors. These findings may be relevant in designing therapeutic strategies aimed at organ optimization prior to transplantation.

Brain death and marginal grafts in liver transplantation

It is well known that most organs for transplantation are currently procured from brain-dead donors; however, the presence of brain death is an important risk factor in liver transplantation. In addition, one of the mechanisms to avoid the shortage of liver grafts for transplant is the use of marginal livers, which may show higher risk of primary non-function or initial poor function. To our knowledge, very few reviews have focused in the field of liver transplantation using brain-dead donors; moreover, reviews that focused on both brain death and marginal grafts in liver transplantation, both being key risk factors in clinical practice, have not been published elsewhere. The present review aims to describe the recent findings and the state-of-the-art knowledge regarding the pathophysiological changes occurring during brain death, their effects on marginal liver grafts and summarize the more controversial topics of this pathology. We also review the therapeutic strategies designed to date to reduce the detrimental effects of brain death in both marginal and optimal livers, attempting to explain why such strategies have not solved the clinical problem of liver transplantation.

Steroid Anti-Inflammatory Effects Did Not Improve Organ Quality in Brain-Dead Rats

Effect of glucocorticoid administration on improving the outcomes of kidney and liver allografts has not been clearly elucidated. This study investigated the effect of prednisolone administration after onset of brain death (BD) on kidney and liver in a controlled rat model of BD. BD was induced in rats by inflating an epidurally placed balloon catheter. Animals were treated with saline or prednisolone (5, 12.5, or 22.5 mg/kg) one hour after the onset of BD. After 4 hours of BD, experiments were terminated and serum and tissues were collected. Tissue gene and protein expression were measured for markers of inflammation, apoptosis, and cellular stress response markers. Prednisolone caused a reduction of plasma levels of IL-6, while the tissue expression of IL-6, IL-1β, and MCP-1 in both kidney and liver were also reduced. Creatinine plasma levels, complement (C3) expression, HSP-70, HO-1, Bcl2/BAX ratio, and PMN influx did not significantly change in kidney nor liver. Plasma AST and LDH levels were increased in the prednisolone treated group. Our results demonstrate prednisolone can has an anti-inflammatory effect mediated through reducing serum circulating cytokines. However, this anti-inflammatory effect does not translate into improved kidney function and indeed was associated with increased liver injury markers.

A systematic review of pharmacological treatment options used to reduce ischemia reperfusion injury in rat liver transplantation

BACKGROUND

Although animal studies models are frequently used for the purpose of attenuating ischemia reperfusion injury (IRI) in liver transplantation (LT), many of pharmacological agents have not become part of clinical routine.

METHODS

A search was performed using the PubMed database to identify agents, from which 58 articles containing 2700 rat LT procedures were selected. The identified pharmacological agents were categorized as follows: I - adenosine agonists, nitric oxide agonists, endothelin antagonists, and prostaglandins, II - Kupffer cell inactivator, III - complement inhibiter, IV - antioxidant, V - neutrophil inactivator, VI -anti-apoptosis agent, VII - heat shock protein and nuclear factor kappa B inducer, VIII - metabolic agent, IX - traditional Chinese medicine, and X - others. Meta-analysis using 7-day-survival rate was also performed with Mantel-Haenszel's Random effects model.

RESULTS

The categorization revealed that the rate of donor-treated experiments in each group was highest for agents from Group II (70%) and VII (71%), whereas it was higher for agents from Group V (83%) in the recipient-treated experiments. Furthermore, 90% of the experiments with agents in Group II provided 7-day-survival benefits. The Risk Ratio (RR) of the meta-analysis was 2.43 [95% CI: 1.88-3.14] with moderate heterogeneity. However, the RR of each of the studies was too model-dependent to be used in the search for the most promising pharmacological agent.

CONCLUSION

With regard to hepatic IRI pathology, the categorization of agents of interest would be a first step in designing suitable multifactorial and pleiotropic approaches to develop pharmacological strategies.

Interest of low-dose hydrocortisone therapy during brain-dead organ donor resuscitation: the CORTICOME study

Introduction

Circulatory failure during brain death organ donor resuscitation is a problem that compromises recovery of organs. Combined administration of steroid, thyroxine and vasopressin has been proposed to optimize the management of brain deceased donors before recovery of organs. However the single administration of hydrocortisone has not been rigorously evaluated in any trial.

Methods

In this prospective multicenter cluster study, 259 subjects were included. Administration of low-dose steroids composed the steroid group (n = 102).

Results

Although there were more patients in the steroid group who received norepinephrine before brain death (80% vs. 66%: P = 0.03), mean dose of vasopressor administered after brain death was significantly lower than in the control group (1.18 ± 0.92 mg/H vs. 1.49 ± 1.29 mg/H: P = 0.03), duration of vasopressor support use was shorter (874 min vs. 1160 min: P < 0.0001) and norepinephrine weaning before aortic clamping was more frequent (33.8% vs. 9.5%: P < 0.0001). Using a survival approach, probability of norepinephrine weaning was significantly different between the two groups (P < 0.0001) with a probability of weaning 4.67 times higher in the steroid group than in the control group (95% CI: 2.30 – 9.49).

Conclusions

Despite no observed benefits of the steroid administration on primary function recovery of transplanted grafts, administration of glucocorticoids should be a part of the resuscitation management of deceased donors with hemodynamic instability.

Prednisolone has a positive effect on the kidney but not on the liver of brain dead rats: a potencial role in complement activation

Background

Contradictory evidence has been published on the effects of steroid treatments on the outcomes of kidney and liver transplantation from brain dead (BD) donors. Our study aimed to evaluate this disparity by investigating the effect of prednisolone administration on BD rats.

Methods

BD induction was performed in ventilated rats by inflating a Fogarty catheter placed in the epidural space. Prednisolone (22.5 mg/kg) was administered 30 min prior to BD induction. After four hours of determination of BD: serum, kidney and liver tissues samples were collected and stored. RT-qPCR, routine biochemistry and immunohistochemistry were performed.

Results

Prednisolone treatment reduced circulating IL-6 and creatinine plasma levels but not serum AST, ALT or LDH. Polymorphonuclear influx assessed by histology, and inflammatory gene expression were reduced in the kidney and liver. However, complement component 3 (C3) expression was decreased in kidney but not in liver. Gene expression of HSP-70, a cytoprotective protein, was down-regulated in the liver after treatment.

Conclusions

This study shows that prednisolone decreases inflammation and improves renal function, whilst not reducing liver injury. The persistence of complement activation and the negative effect on protective cellular mechanisms in the liver may explain the disparity between the effects of prednisolone on the kidney and liver of BD rats. The difference in the molecular and cellular responses to prednisolone administration may explain the contradictory evidence of the effects of prednisolone on different organ types from brain dead organ donors.