Impact of reversible cardiac arrest in the brain-dead organ donor on the outcome of adult liver transplantation

Use of liver grafts from cadaveric donors: Implementation impact of a local evaluation and procurement team in Mexico

INTRODUCTION AND AIMS

Cadaveric donor liver graft retrieval is complex in Mexico. The aim of the present article was to present the experience in liver graft use during the first year of work of a local evaluation and procurement team.

MATERIALS AND METHODS

We reviewed the organ donation report forms and allocation offer records covering the time frame of December 15, 2017 to December 15, 2018, and registered the donor characteristics, causes of organ discard, causes of declined offers, transport time, and graft and recipient survival at 30 days.

RESULTS

There were 17 donations and we completed the evaluation of 14. Two donors were considered ideal (14.2%) and 12 were expanded criteria donors (ECDs) (85.7%). Two grafts with steatosis were not offered (14.2%). Twelve liver grafts were offered 88 times (mean 7.6 offers per graft). The acceptance rate was 6% for public hospitals and 23.6% for private hospitals (p = 0.016). One graft was discarded during the procurement process due to steatosis. The rate of use after evaluation was 78.5% (11/14). All the grafts were procured by the local team and 9 (81.8%) were transported by commercial airline (median 240 min, range 85 min). Graft and recipient survival at 30 days was 100%.

CONCLUSIONS

The participation of a local evaluation and procurement team notably increased liver graft use with excellent results. Commercial airline transportation of the grafts to all active transplantation centers of the country resulted in cold ischemia times <6 h.

Liver transplantation from brain-dead donors on mechanical circulatory support: a systematic review of the literature

Mechanical circulatory support (MCS) refers to a range of rescue devices to assist circulation for the treatment of heart failure, including venoarterial extracorporeal membrane oxygenation (VA-ECMO) and ventricular assist devices (VADs). This review aims at evaluating the transplant outcome of the livers procured from brain-dead donors on MCS, who are currently considered as having extended criteria. We identified 22 records (17 on VA-ECMO and 5 on VADs), most of which (68.2%) were case reports. We performed a meta-analysis only when the outcome was reported homogeneously among studies; otherwise, we illustrated the results with narrative synthesis. A total of 156 liver transplants (LTs) have been reported, where VA-ECMO was initiated in the donor with resuscitative intent or as a bridge to donation. Early graft survival approached 100% in most studies. The pooled rate of primary nonfunction was 1% (95% CI: 0-3%). Only three successful LTs from VAD donors have been reported. Particular attention should be paid to cardiological history, biochemical tests, and imaging, as well as MCS parameters, to determine graft eligibility for transplantation. Although further analysis is needed in this field, the results of this review advocate a more systematic consideration of brain-dead patients on MCS as potential liver donors.

Impact of donor preprocurement cardiac arrest on clinical outcomes in pediatric deceased donor liver transplantation

PPCA has historically been considered detrimental to donor quality in LT, but transplantation of grafts from this group of donors is now routine. Our study aims to evaluate the outcomes associated with use of donors with a history of PPCA in the pediatric population. This study is a single-center retrospective analysis of all pediatric LTs performed over an 18-year period. Donors and recipients were stratified by the presence and length of donor PPCA time. Preprocurement donor and post-transplant recipient laboratory values were collected to assess the degree of ischemic liver injury associated with each donor group. Cox regression analysis was used to compare survival. The records for 130 deceased pediatric LT donors and corresponding recipients were reviewed. There were 73 (56%) non-PPCA donors and 57 (44%) PPCA donors. Donors that experienced a PPCA event demonstrated a higher median, pretransplant peak alanine aminotransferase (ALT) level (P < .001). When comparing post-transplant recipient median ALT levels, donors with any PPCA had lower median peak ALT (P = .15) and day 3 ALT (P = .43) levels than the non-PPCA group. Rates of early graft loss did not differ. The PPCA group with >40 minutes of ischemia had markedly lower survival at 10 years, but this finding did not reach statistical significance. Liver grafts from donors with or without PPCA demonstrated no statistically significant differences in function or survival. A history of donor PPCA alone should not be used as an exclusionary criterion in pediatric liver transplantation.

Influence of 4 preservation solutions on ICU stay, graft and patient survival following liver transplantation

OBJECTIVE

The goal of this study was to evaluate the prognostic role of four preservation solutions in liver transplantation (LT).

PATIENTS AND METHODS

This is a retrospective study originating from 22 French centers performing LT, registered in the prospective databank of the Cristal Biomedicine Agency between 2008 and 2013. The preservation solutions used were Celsior (CS), Institut Georges Lopez (IGL)-1, Solution de Conservation des Organes et des Tissus (SCOT) 15 and University of Wisconsin (UW) solutions. Exclusion criteria were preservation with unknown or inhomogeneous solutions, or Histidine-tryptophan-ketoglutarate (HTK) solution (representing only 3% of LT). Patient survival was the main endpoint. Secondary endpoints were graft survival and duration of stay in intensive care.

RESULTS

Of 6347 LT performed, 4928 were included in this study, for which the distribution of preservation solution was CS (30%), IGL-1 (44%), SCOT 15 (10%) and UW (16%). Patient survival was 86%, 80% and 74% at 1, 3 and 5 years after LT, respectively, without any statistically significant difference between the four solutions (P=0.78). Graft survival was 82%, 75% and 69% at 1, 3 and 5 years after LT, respectively, without any statistically significant difference between the four solutions (P=0.80). Duration of intensive care was different according to the solution used in univariate analysis (P<0.001), but this effect disappeared in multivariate analysis when the center performing the transplantation was accounted for.

CONCLUSION

The type of preservation solution used (CS, IGL-1, SCOT 15 or UW) did not have any influence on patient or graft survival after LT.

Liver Procurement from Poisoned Donors: A Survival Study

OBJECTIVES

Although transplant teams understand the effects of donor characteristics on liver transplant outcomes, few studies have investigated the quality of livers obtained from poisoned donors. The aim of this study was to compare livers procured from poisoned donors with a matched control group.

MATERIALS AND METHODS

Liver transplant outcomes from poisoned donors and from donors with trauma-induced death (as the control group) were compared using data of an Organ Procurement Unit from 2000 to 2013. Procured livers were evaluated via histology findings before transplant. Recipient characteristics were assessed in both groups, and immediate and medium-term (up to 5 years after transplant) survival rates were compared with the use of Kaplan-Meier analyses and log-rank tests.

RESULTS

Over a 13-year organ donation program, 1485 livers from brain dead patients were donated. Among them, 115 poisoned donors were evaluated for liver grafts; of these, 74 successful liver transplants were performed. In the poisoned donors, the incidence of reversed cardiac arrest was 54.1%. Likewise, acute kidney injury was detected in 14.9% of the patients, and 16.2% needed urgent dialysis either for clearance of the toxic agents or for treatment of acute kidney injury. No significant differences were observed in 1- to 5-year survival rates, and log-rank test also showed a significance level of 0.83.

CONCLUSIONS

Proper case selection strategies can be implemented to expand the donor pool, including use of poisoned donors. Hence, poisoning is not a contra-indication for a referral, which could lead to decreased mortality for patients requiring a liver transplant.

Impact of Donor Pre-Procurement Cardiac Arrest (PPCA) on Clinical Outcomes in Liver Transplantation

Background

Transplantation of liver grafts from deceased donors who experienced cardiac arrest prior to liver procurement is now common. This single-center study analyzed the impact of pre-donation arrest time on clinical outcomes in liver transplantation.

Material/Methods

Records of all orthotopic liver transplants performed at a single center over a 15-year period were reviewed. Donor records were reviewed and total arrest time was calculated as cumulative minutes. Post-transplant liver graft function was assessed using laboratory values. Graft survival was assessed with Cox regression analysis.

Results

Records for 1830 deceased donor transplants were reviewed, and 521 donors experienced pre-procurement cardiac arrest (28%). Median arrest time was 21 min (mean 25 min, range 1–120 min). After transplant, the peak alanine aminotransferase and bilirubin levels for liver grafts from donors with arrest were lower compared to those for donors without arrest (p<0.001). Early allograft dysfunction occurred in 25% (arrest) and 28% (no arrest) of patients (p=0.22). There were no differences in risk of early graft loss (3% vs. 3%, p=0.84), length of hospital stay (10 vs. 10 days, p=0.76), and 1-year graft survival (89% vs. 89%, p=0.94). Cox regression analysis comparing 4 groups (no arrest, <20 min, 20–40 min, and >40 min arrest) demonstrated no statistically significant difference in survival at 10 years. Subgroup analysis of 93 donation after cardiac death grafts showed no significant difference for these same outcomes.

Conclusions

These results support the use of select deceased liver donors who experience pre-donation cardiac arrest. Pre-donation arrest may be associated with less early allograft dysfunction, but had no impact on long-term clinical outcomes. The results for donation after cardiac death donors were similar.

Donor liver quality after hypovolemic shock and venous systemic oxygen persufflation in an experimental animal model

BACKGROUND

The ever growing demand for liver transplantation inevitably necessitates an expansion of the donor pool. Utilization of "shock organs" is considered suboptimal to date while the associated outcome has hardly been investigated.

MATERIALS AND METHODS

Male Wistar rats underwent a period of 30 min of hypovolemic shock. After 24 h livers were explanted and prior to reperfusion underwent either 18 h of cold storage (CS; N = 6) or 17 h of CS followed by 60 min venous systemic oxygen persufflation (VSOP; N = 6). The outcome of "shock organs (SHBD)" was compared to heart-beating donor (HBD; N = 12) as positive control and non-heart-beating donor (NHBD; N = 12) as negative control animal groups. Liver function was assessed by measuring enzyme release (AST, ALT, LDH), bile production, portal vein pressure and hepatic oxygen uptake during reperfusion. For reperfusion, the isolated perfused rat liver system was used.

RESULTS

Liver function was severely limited in NHBD group compared to HBD organs after 18 h of CS (e.g., AST; HBD: 32.25 ± 7.25 U/l vs. NHBD: 790 ± 414.56 U/l; p < 0.005). VSOP improved liver function of NHBD organs significantly (AST; NHBD + VSOP: 333.6 ± 149.1 U/l; p < 0.005). SHBD organs showed a comparable outcome to HBD and clearly better results than NHBD organs after 18 h of CS (AST; SHBD: 76.4 ± 21.9 U/l). After 17 h of CS accompanied by 60 min VSOP, no improvement concerning liver function and integrity of SHBD organs was observed while the results were severely deteriorated by VSOP resulting in higher enzyme release (AST; SHBD + VSOP: 213 ± 61 U/l, p < 0.001), higher portal vein pressure (SHBD: 10.8 ± 1.92 mm Hg vs. SHBD + VSOP: 21.6 ± 8.8 mm Hg; p < 0.05) and lower hepatic oxygen uptake (SHBD: 321.75 ± 3.87 ml/glw/min vs. SHBD + VSOP: 395.8 ± 46.64 ml/glw/min, p < 0.05) at 24 h.

CONCLUSIONS

Our data suggest that the potential of "shock organs" within liver transplantation may be underestimated. If our findings are reproducable in humans, SHBD grafts should be considered as a valuable source for expanding the thus far limited donor pool.

Impact of Deceased Donor Cardiac Arrest Time on Postpancreas Transplant Graft Function and Survival

Introduction

Transplantation of pancreas allografts from donors that have experienced preprocurement cardiopulmonary arrest (PPCA) is not common, though use of PPCA grafts is routine in liver and kidney transplantation. This article reviews a large number of PPCA pancreas grafts at a single center and reports posttransplant outcomes including early graft dysfunction, length of hospital stay, rejection, and early and late graft survival.

Methods

Preprocurement cardiopulmonary arrest, arrest time, and donor and recipient pancreatic enzyme levels were collected from electronic and written medical records. The PPCA donors were stratified into 4 groups: none, less than 20 minutes, 20-39 minutes, and 40 minutes or greater. Graft survival was assessed at 7 and 90 days and at 1 year. Long-term graft survival was assessed by Cox regression analysis.

Results

The records of 606 pancreas transplants were reviewed, including 328 (54%) simultaneous pancreas and kidney transplants. Preprocurement cardiopulmonary arrest occurred in 176 donors (29%; median time, 20 minutes). Median peak donor lipase was higher in PPCA donors (40 μ/L vs 29 μ/L, P = 0.02). Posttransplant, peak recipient amylase, and lipase levels were similar (P = 0.63). Prolonged arrest time (>40 minutes) was associated with higher donor peak lipase and lower recipient peak amylase (P = 0.05 for both). Stratified by donor arrest time, there was no difference in 7-day, 90-day, or 1-year graft survival. Cox regression comparing the 4 groups demonstrated no statistical difference in 10-year survival.

Conclusions

These results support transplantation of pancreas allografts from PPCA donors. Prolonged asystole was associated with higher peak donor serum lipase but lower peak recipient serum amylase. There were no differences in allograft survival.

Time trends in organ donation after neurologic determination of death: a cohort study

BACKGROUND

The cause of brain injury may influence the number of organs that can be procured and transplanted with donation following neurologic determination of death. We investigated whether the distribution of causes responsible for neurologic death has changed over time and, if so, whether this has had an impact on organ quality, transplantation rates and recipient outcomes.

METHODS

We performed a cohort study involving consecutive brain-dead organ donors in southern Alberta between 2003 and 2014. For each donor, we determined last available measures of organ injury and number of organs transplanted, and compared these variables for various causes of neurologic death. We compared trends to national Canadian data for 2000-2013 (2000-2011 for Quebec).

RESULTS

There were 226 brain-dead organ donors over the study period, of whom 100 (44.2%) had anoxic brain injury, 63 (27.9%) had stroke, and 51 (22.6%) had traumatic brain injury. The relative proportion of donors with traumatic brain injury decreased over time (> 30% in 2003-2005 v. 6%-23% in 2012-2014) (p = 0.004), whereas that with anoxic brain injury increased (14%-37% v. 46%-80%, respectively) (p < 0.001). Nationally, the annual number of brain-dead donors with traumatic brain injury decreased from 4.4 to less than 3 per million population between 2000 and 2013, and that with anoxic brain injury increased from 1.1 to 3.1 per million. Donors with anoxic brain injury had higher concentrations of creatinine, alanine aminotransferase and troponin T, and lower PaO2/FIO2 and urine output than donors with other diagnoses. The average number of organs transplanted per donor was 3.6 with anoxic brain injury versus 4.5 with traumatic brain injury or stroke (p = 0.002).

INTERPRETATION

Anoxic brain injury has become a leading cause of organ donation after neurologic determination of death in Canada. Organs from donors with anoxic brain injury have a greater degree of injury, and fewer are transplanted. These findings have implications for availability of organs for transplantation in patients with end-stage organ failure.

Initial Poor Function and Primary Nonfunction in Deceased-Donor Orthotopic Liver Transplantation Maintaining Short Cold Ischemic Time

BACKGROUND

Nations with emerging deceased-donor liver transplantation programs, such as India, face problems associated with poor donor maintenance. Cold ischemic time (CIT) is typically maintained short by matching donor organ recovery and recipient hepatectomy to achieve maximum favorable outcome. We analyzed different extended criteria donor factors including donor acidosis, which may act as a surrogate marker of poor donor maintenance, to quantify the risk of primary nonfunction (PNF) or initial poor function (IPF).

METHODS

A single-center retrospective outcome analysis of prospectively collected data of patients undergoing deceased-donor liver transplantation over 2 years to determine the impact of different extended criteria donor factors on IPF and PNF.

RESULTS

From March 2013 to February 2015, a total of 84 patients underwent deceased-donor liver transplantation. None developed PNF. Thirteen (15.5%) patients developed IPF. Graft macrosteatosis and donor acidosis were only related to IPF ( P = .002 and P = .032, respectively). Cold ischemic time was maintained short (81 cases ≤8 hours, maximum 11 hours) in all cases.

CONCLUSION

Poor donor maintenance as evidenced by donor acidosis and graft macrosteatosis had significant impact in developing IPF when CIT is kept short. Similar study with larger sample size is required to establish extended criteria cutoff values.

Effect of donor cardiac arrest and arrest duration on outcomes of lung transplantation

BACKGROUND

Limited data are available about lung transplantation (LTx) from donors suffering cardiac arrest (CA) prior to actual donation.

METHODS

A retrospective analysis of LTx performed between January 2007 and September 2012 was done with the focus on CA in donors. The recipients were grouped depending on the history of donor CA and CA duration (downtime) as: No cardiac arrest ("NoCA"), CA downtime less than 20 min ("CA < 20"), and CA downtime equal to or more than 20 min ("CA > 20"). Early and mid-term outcomes after LTx were compared among the three groups.

RESULTS

A total of 237 LTx were performed during the study period. One hundred eighty-eight patients received organs from "NoCA" donors, 25 from "CA < 20" donors, and 24 patients from "CA > 20" donors. There was a trend toward better overall cumulative survival in both CA groups (log rank p = 0.076) whereas the survival in the "CA > 20" group was significantly better than in the "NoCA" group in the subgroup analysis (log rank p = 0.045). Freedom from bronchiolitis obliterans syndrome (BOS) also increased with increase in CA duration, although it did not reach statistical significance.

CONCLUSIONS

Transplantation of lungs from donors with a history of CA is safe and feasible. Longer duration of cardiac arrest may improve the outcomes after the LTx in terms of survival and freedom from BOS.

Safely expanding the donor pool: brain dead donors with history of temporary cardiac arrest

BACKGROUND & AIMS

Cardiac arrest (CA) in deceased organ donors can potentially be associated with ischaemic organ injury, resulting in allograft dysfunction after liver transplantation (LT). The aim of this study was to analyse the influence of cardiac arrest in liver donors.

METHODS

We evaluated 884 consecutive adult patients undergoing LT at our Institution from September 2003 to December 2011. Uni- and multivariable analyses was performed to identify predictive factors of outcome and survival for organs from donors with (CA donor) and without (no CA donor) a history of cardiac arrest.

RESULTS

We identified 77 (8.7%) CA donors. Median resuscitation time was 16.5 (1-150) minutes. Allografts from CA donors had prolonged CIT (p = 0.016), were obtained from younger individuals (p < 0.001), and had higher terminal preprocurement AST and ALT (p < 0.001) than those of no CA donors. 3-month, 1-year and 5-year survival for recipients of CA donor grafts was 79%, 76% and 57% and 72.1%, 65.1% and 53% for no CA donor grafts (log rank p = 0.435). Peak AST after LT was significantly lower in CA donor organs than in no CA donor ones (886U/l vs 1321U/l; p = 0.031). Multivariable analysis identified CIT as a risk factor for both patient and graft survival in CA donors.

CONCLUSION

This analysis represents the largest cohort of liver donors with a history of cardiac arrest. Reasonable selection of these donors constitutes a safe approach to the expansion of the donor pool. Rapid allocation and implantation with diminution of CIT may further improve the outcomes of livers from CA donors.

A score model for the continuous grading of early allograft dysfunction severity

Early allograft dysfunction (EAD) dramatically influences graft and patient outcomes. A lack of consensus on an EAD definition hinders comparisons of liver transplant outcomes and management of recipients among and within centers. We sought to develop a model for the quantitative assessment of early allograft function [Model for Early Allograft Function Scoring (MEAF)] after transplantation. A retrospective study including 1026 consecutive liver transplants was performed for MEAF score development. Multivariate data analysis was used to select a small number of postoperative variables that adequately describe EAD. Then, the distribution of these variables was mathematically modeled to assign a score for each actual variable value. A model, based on easily obtainable clinical parameters (ie, alanine aminotransferase, international normalized ratio, and bilirubin) and scoring liver function from 0 to 10, was built. The MEAF score showed a significant association with patient and graft survival at 3-, 6- and 12-month follow-ups. Hepatic steatosis and age for donors; cold/warm ischemia times and postreperfusion syndrome for surgery; and intensive care unit and hospital stays, Model for End-Stage Liver Disease and Child-Pugh scores, body mass index, and fresh frozen plasma transfusions for recipients were factors associated significantly with EAD. The model was satisfactorily validated by its application to an independent set of 200 patients who underwent liver transplantation at a different center. In conclusion, a model for the quantitative assessment of EAD severity has been developed and validated for the first time. The MEAF provides a more accurate graft function assessment than current categorical classifications and may help clinicians to make early enough decisions on retransplantation benefits. Furthermore, the MEAF score is a predictor of recipient and graft survival. The standardization of the criteria used to define EAD may allow reliable comparisons of recipients' treatments and transplant outcomes among and within centers.

Metabolomics discloses donor liver biomarkers associated with early allograft dysfunction

BACKGROUND & AIMS

Early allograft dysfunction (EAD) dramatically influences graft and patient outcome after orthotopic liver transplantation and its incidence is strongly determined by donor liver quality. Nevertheless, objective biomarkers, which can assess graft quality and anticipate organ function, are still lacking. This study aims to investigate whether there is a preoperative donor liver metabolomic biosignature associated with EAD.

METHODS

A comprehensive metabolomic profiling of 124 donor liver biopsies collected before transplantation was performed by mass spectrometry coupled to liquid chromatography. Donor liver grafts were classified into two groups: showing EAD and immediate graft function (IGF). Multivariate data analysis was used to search for the relationship between the metabolomic profiles present in donor livers before transplantation and their function in recipients.

RESULTS

A set of liver graft dysfunction-associated biomarkers was identified. Key changes include significantly increased levels of bile acids, lysophospholipids, phospholipids, sphingomyelins and histidine metabolism products, all suggestive of disrupted lipid homeostasis and altered histidine pathway. Based on these biomarkers, a predictive EAD model was built and further evaluated by assessing 24 independent donor livers, yielding 91% sensitivity and 82% specificity. The model was also successfully challenged by evaluating donor livers showing primary non-function (n=4).

CONCLUSIONS

A metabolomic biosignature that accurately differentiates donor livers, which later showed EAD or IGF, has been deciphered. The remarkable metabolomic differences between donor livers before transplant can relate to their different quality. The proposed metabolomic approach may become a clinical tool for donor liver quality assessment and for anticipating graft function before transplant.