Liver Transplantation without Perioperative Transfusions Single-Center Experience Showing Better Early Outcome and Shorter Hospital Stay

Predictive role of hepatic venous pressure gradient in bleeding events among patients with cirrhosis undergoing orthotopic liver transplantation

Background & Aims

Major bleeding events during orthotopic liver transplantation (OLT) are associated with poor outcomes. The proportion of this risk related to portal hypertension is unclear. Hepatic venous pressure gradient (HVPG) is the gold standard for estimating portal hypertension. The aim of this study was to analyze the ability of HVPG to predict intraoperative major bleeding events during OLT in patients with cirrhosis.

Methods

We retrospectively analyzed a prospective database including all patients with cirrhosis who underwent OLT between 2010 and 2020 and had liver and right heart catheterizations as part of their pre-transplant assessment. The primary endpoint was the occurrence of an intraoperative major bleeding event.

Results

The 468 included patients had a median HVPG of 17 mmHg [interquartile range, 13-22] and a median MELD on the day of OLT of 16 [11-24]. Intraoperative red blood cell transfusion was required in 72% of the patients (median 2 units transfused), with a median blood loss of 1,000 ml [575-1,500]. Major intraoperative bleeding occurred in 156 patients (33%) and was associated with HVPG, preoperative hemoglobin level, severity of cirrhosis at the time of OLT (MELD score, ascites, encephalopathy), hemostasis impairment (thrombocytopenia, lower fibrinogen levels), and complications of cirrhosis (sepsis, acute-on-chronic liver failure). By multivariable regression analysis with backward elimination, HVPG, preoperative hemoglobin level, MELD score, and tranexamic acid infusion were associated with the primary endpoint. Three categories of patients were identified according to HVPG: low-risk (HVPG <16 mmHg), high-risk (HVGP ≥16 mmHg), and very high-risk (HVPG ≥20 mmHg).

Conclusions

HVPG predicted major bleeding events in patients with cirrhosis undergoing OLT. Including HVPG as part of pre-transplant assessment might enable better anticipation of the intraoperative course.

Impact and implications

Major bleeding events during orthotopic liver transplantation (OLT) are associated with poor outcomes but the proportion of this risk related to portal hypertension is unclear. Our work shows that hepatic venous pressure gradient (HVPG), the gold standard for estimating portal hypertension, is a strong predictor of major bleeding events and blood loss volume in patients with cirrhosis undergoing OLT. Three groups of patients can be identified according to their risk of major bleeding events: low-risk patients with HVPG <16 mmHg, high-risk patients with HVPG ≥16 mmHg, and very high-risk patients with HVPG ≥20 mmHg. HVPG could be systematically included in the pre-transplant assessment to anticipate intraoperative course and tailor patient management.

An overview of unresolved issues in the perioperative management of liver transplant patients

Over the past decade, the field of solid organ transplantation has undergone significant changes, with some of the most notable advancements occurring in liver transplantation. Recent years have seen substantial progress in preoperative patient optimization protocols, anesthesia monitoring, coagulation management, and fluid management, among other areas. These improvements have led to excellent perioperative outcomes for all surgical patients, including those undergoing liver transplantation. In the last few decades, there have been numerous publications in the field of liver transplantation, but controversies related to perioperative management of liver transplant recipients persist. In this review article, we address the unresolved issues surrounding the anesthetic management of patients scheduled for liver transplantation.

Preoperative Fibrinogen Level and Bleeding in Liver Transplantation for End-stage Liver Disease: A Cohort Study

BACKGROUND

Liver transplantation is a high-risk surgery associated with important perioperative bleeding and transfusion needs. Uncertainties remain on the association between preoperative fibrinogen level and bleeding in this population.

METHODS

We conducted a cohort study that included all consecutive adult patients undergoing a liver transplantation for end-stage liver disease in 1 center. We analyzed the association between the preoperative fibrinogen level and bleeding-related outcomes. Our primary outcome was intraoperative blood loss, and our secondary outcomes were estimated perioperative blood loss, intraoperative and perioperative red blood cell transfusions, reinterventions for bleeding and 1-y graft and patient survival. We estimated linear regression models and marginal risk models adjusted for all important potential confounders. We used restricted cubic splines to explore potential nonlinear associations and reported dose-response curves.

RESULTS

We included 613 patients. We observed that a lower fibrinogen level was associated with a higher intraoperative blood loss, a higher estimated perioperative blood loss and a higher risk of intraoperative and perioperative red blood cell transfusions (nonlinear effects). Based on an exploratory analysis of the dose-response curves, these effects were observed below a threshold value of 3 g/L for these outcomes. We did not observe any association between preoperative fibrinogen level and reinterventions, 1-y graft survival or 1-y patient survival.

CONCLUSIONS

This study suggests that a lower fibrinogen level is associated with bleeding in liver transplantation. The present results may help improving the selection of patients for further studies on preoperative fibrinogen administration in liver transplant recipients with end-stage liver disease.

The effect of thromboelastogram-guided transfusion on postoperative complications and transfusion requirement in the post-reperfusion period in liver transplantation surgery

Background/Aim: Liver transplantation surgery is one of the most common abdominal surgeries requiring blood transfusion. Coagulation parameters vary during the perioperative period because of the patient profile. Blood transfusion management should be carefully controlled to avoid causing dysfunction in the newly transplanted organ. Various laboratory parameters are used to achieve this. This study aimed to investigate the effect of transfusion managed by conventional coagulation tests or thromboelastogram (TEG) on blood product consumption and postoperative outcomes in the post-reperfusion period. Methods: The records of 90 recipients who underwent transplantation between January 1, 2012, and November 30, 2022, were retrospectively analyzed. Twenty patients who were administered blood transfusion under TEG guidance in the post-reperfusion period constituted the case group, while 20 patients non-consecutive randomly selected among other patients who were administered blood transfusion with conventional coagulation tests constituted the control group. In conclusion, 40 patients were included in this retrospective case-control study. We retrospectively analyzed demographic data, surgical data, perioperative laboratory parameters, intraoperative total and post-reperfusion blood and blood product transfusions, TEG parameters, and postoperative complications. Results: No difference was found between the groups regarding demographic data, etiological factors, surgical data, and preoperative laboratory parameters (P>0.05). There was a significant decrease in the amount of fresh frozen plasma (FFP) transfused in the case group compared to the control group in the intraoperative total and post-reperfusion period (P=0.011, P=0.003). There was no difference between the groups regarding other blood product transfusions and postoperative complications (P>0.05). Regarding the effects of intraoperative total and post-reperfusion blood and blood products on ventilator stay, intensive care unit stay, length of stay (LOS), hepatic artery thrombosis, graft rejection, postoperative kidney damage, and first 28-day mortality, only a weak negative correlation was found between intraoperative total and postreperfusion fibrinogen use and LOS (r=-0.325/P=0.041, r=-0.354/P=0.025). Conclusion: TEG-guided transfusion in the post-reperfusion period reduced total blood product consumption. Besides, the increase in the use of fibrin has led to a decrease in LOS. However, using TEG has no significant effect on postoperative mortality and morbidity. TEG and an objective assessment of patient clinical status may be an ideal guide for transfusion strategy.

Characteristics and Outcomes of Liver Transplantation Recipients after Tranexamic Acid Treatment and Platelet Transfusion: A Retrospective Single-Centre Experience

Background and Objectives: Patients undergoing liver transplantation (LT) often require increased blood product transfusion due to pre-existing coagulopathy and intraoperative fibrinolysis. Strategies to minimise intraoperative bleeding and subsequent blood product requirements include platelet transfusion and tranexamic acid (TXA). Prophylactic TXA administration has been shown to reduce bleeding and blood product requirements intraoperatively. However, its clinical use is still debated. The aim of this study was to report on a single-centre practice and analyse clinical characteristics and outcomes of LT recipients according to intraoperative treatment of TXA or platelet transfusion. Materials and Methods: This was a retrospective observational cohort study in which we reviewed 162 patients' records. Characteristics, intraoperative requirement of blood products, postoperative development of thrombosis and outcomes were compared between patients without or with intraoperative TXA treatment and without or with platelet transfusion. Results: Intraoperative treatment of TXA and platelets was 53% and 57.40%, respectively. Patients who required intraoperative administration of TXA or platelet transfusion also required more transfusion of blood products. Neither TXA nor platelet transfusion were associated with increased postoperative development of hepatic artery and portal vein thrombosis, 90-day mortality or graft loss. There was a significant increase in the median length of intensive care unit (ICU) stay in those who received platelet transfusion only (2.00 vs. 3.00 days; p = 0.021). Time to extubate was significantly different in both those who required TXA and platelet transfusion intraoperatively. Conclusions: Our analysis indicates that LT recipients still required copious intraoperative transfusion of blood products, despite the use of intraoperative TXA and platelets. Our findings have important implications for current transfusion practice in LT recipients and may guide clinicians to act upon these findings, which will support global efforts to encourage a wider use of TXA to reduce transfusion requirements, including platelets.

Intraoperative transfusion management, antifibrinolytic therapy, coagulation monitoring and the impact on short-term outcomes after liver transplantation-A systematic review of the literature and expert panel recommendations

BACKGROUND

Liver transplantation (LT) is frequently complicated by coagulopathy associated with end-stage liver disease (ESLD), that is, often multifactorial.

OBJECTIVES

The objective of this systematic review was to identify evidence based intraoperative transfusion and coagulation management strategies that improve immediate and short-term outcomes after LT.

METHODS

PRISMA-guidelines and GRADE-approach were followed. Three subquestions were formulated. (Q); Q1: transfusion management; Q2: antifibrinolytic therapy; and Q3: coagulation monitoring.

RESULTS

Sixteen studies were included for Q1, six for Q2, and 10 for Q3. Q1: PRBC and platelet transfusions were associated with higher mortality. The use of prothrombin complex concentrate (PCC) and fibrinogen concentrate (FC) were not associated with reductions in intraoperative transfusion or increased thrombotic events. The use of cell salvage was not associated with hepatocellular carcinoma (HCC) recurrence or mortality. Cell salvage and transfusion education significantly decreased blood product transfusions. Q2: Epsilon-aminocaproic acid (EACA) and tranexamic acid (TXA) were not associated with decreased blood product transfusion, improvements in patient or graft survival, or increases in thrombotic events. Q3: Viscoelastic testing (VET) was associated with decreased allogeneic blood product transfusion compared to conventional coagulation tests (CCT) and is likely to be cost-effective. Coagulation management guided by VET may be associated with increases in FC and PCC use.

CONCLUSION

Q1: A specific blood product transfusion practice is not recommended (QOE; low | Recommendation; weak). Cell salvage and educational interventions are recommended (QOE: low | Grade of Recommendation: moderate). Q2: The routine use of antifibrinolytics is not recommended (QOE; low | Recommendation; weak). Q3: The use of VET is recommended (QOE; low-moderate | Recommendation; strong).

Blood loss during liver transplantation is a predictor of postoperative thrombosis

Liver transplantation (LT) is an effective way to cure end-stage liver diseases (ESLDs), which have generally been regarded as examples of acquired bleeding disorders. However, postoperative thrombosis after LT is recognised and remains a life-threatening complication. This study aimed to show that blood loss during LT is a predictor of postoperative thrombosis and to establish a predictive model. We analysed the medical records of all patients who underwent LT at the First Affiliated Hospital of Xi'an Jiaotong University from January 2017 to April 2019 to identify the risk factors for post-transplant thrombosis. The predictive nomogram was established based on independent predictors identified by logistic regression analysis. Blood loss during LT of ≥31.25 mL/kg can predict postoperative thrombosis, and the nomogram achieved an accurate prediction.

Intraoperative phlebotomies and bleeding in liver transplantation: a historical cohort study and causal analysis

BACKGROUND

Liver transplantation is associated with major bleeding and red blood cell (RBC) transfusions. No well-designed causal analysis on interventions used to reduce transfusions, such as an intraoperative phlebotomy, has been conducted in this population.

METHODS

We conducted a historical cohort study among liver transplantations performed from July 2008 to January 2021 in a Canadian centre. The exposure was intraoperative phlebotomy. The outcomes were blood loss, perioperative RBC transfusions (intraoperative and up to 48 hr after surgery), intraoperative RBC transfusions, and one-year survival. We estimated marginal multiplicative factors (MFs), risk differences (RDs), and hazard ratios by inverse probability of treatment weighting both among treated patients and the whole population. Estimates are reported with 95% confidence intervals (CIs).

RESULTS

We included 679 patients undergoing liver transplantations of which 365 (54%) received an intraoperative phlebotomy. A phlebotomy did not reduce bleeding, transfusion risks, or mortality when estimated among the treated but reduced bleeding and transfusion risks when estimated among the whole population (MF, 0.85; 95% CI, 0.72 to 0.99; perioperative RD, -15.2%; 95% CI, -26.1 to -0.8; intraoperative RD, -14.7%; 95% CI, -23.2 to -2.8). In a subgroup analysis on 584 patients with end-stage liver disease, slightly larger effects were observed on both transfusion risks when estimated among the whole population while beneficial effects were observed on the intraoperative transfusion risk when estimated among the treated population.

CONCLUSION

The use of intraoperative phlebotomy was not consistently associated with better outcomes in all targets of inference but may improve outcomes among the whole population.

STUDY REGISTRATION

www.

CLINICALTRIALS

gov (NCT04826666); registered 1 April 2021.

A Global Definition of Patient Blood Management

While patient blood management (PBM) initiatives are increasingly adopted across the globe as part of standard of care, there is need for a clear and widely accepted definition of PBM. To address this, an expert group representing PBM organizations, from the International Foundation for Patient Blood Management (IFPBM), the Network for the Advancement of Patient Blood Management, Haemostasis and Thrombosis (NATA), the Society for the Advancement of Patient Blood Management (SABM), the Western Australia Patient Blood Management (WAPBM) Group, and OnTrac (Ontario Nurse Transfusion Coordinators) convened and developed this definition: "Patient blood management is a patient-centered, systematic, evidence-based approach to improve patient outcomes by managing and preserving a patient's own blood, while promoting patient safety and empowerment." The definition emphasizes the critical role of informed choice. PBM involves the timely, multidisciplinary application of evidence-based medical and surgical concepts aimed at screening for, diagnosing and appropriately treating anemia, minimizing surgical, procedural, and iatrogenic blood losses, managing coagulopathic bleeding throughout the care and supporting the patient while appropriate treatment is initiated. We believe that having a common definition for PBM will assist all those involved including PBM organizations, hospital administrators, individual clinicians and policy makers to focus on the appropriate issues when discussing and implementing PBM. The proposed definition is expected to continue to evolve, making this endeavor a work in progress.

Validation of McCluskey Index for Massive Blood Transfusion Prediction in Liver Transplantation

BACKGROUND

The McCluskey index has been used as a tool to predict massive bleeding (>6 red blood cells units) during orthotropic liver transplantation. The objective of this study is to verify its efficacy at our institution.

MATERIALS AND METHODS

Between May 1998 and December 2017, we performed 1216 orthotropic liver transplantations, of which 1016 had sufficient data registered with respect to hemoderivative transfusion. We divided these patients into groups based on the original study of McCluskey. This study was approved by the ethical committee of our Institution and was performed in accordance with the Declaration of Helsinki.

RESULTS

The mean Model for End-Stage Liver Disease score in the 4 groups was 7.5 (range, 7-8) for low risk; 13 (range, 3-32) for medium risk, 17 (range, 8-41) for high risk, and 25 (range, 11-36) for very high risk (P < .001). No significant differences were observed regarding body mass index or hospital stay. No differences have been found in the number of suboptimal donors among the groups. With respect to hemoderivative transfusions, we observed the following for red blood cells: 7 (range, 6-8) units for low risk; 5.5 (range, 0-74) for medium risk; 7 (range, 0-73) for high risk, and 12 (range, 5-30) for very high risk (P < .001) and transfusion of plasma: 12 (range, 10-15) units for low risk; 11 (range, 0-89) for medium risk; 14 (range, 0-76) for high risk, and 13 (range, 3-30) for very high risk (P = .001).

CONCLUSIONS

The McCluskey index is a good indicator of the risk of hemorrhage and hence the necessity of transfusion.

Hemoderivative Transfusion in Liver Transplantation: Comparison Between Recipients of Grafts From Brain Death Donors and Recipients of Uncontrolled Donors After Circulatory Death

INTRODUCTION

Intraoperative bleeding during liver transplantation has been correlated with a higher risk of morbidity and mortality and decrease in patient and graft survival.

MATERIALS AND METHODS

Between January 2006 and December 2016 we performed 783 orthotopic liver transplants. After applying exclusion criteria, we found liver grafts from donors after circulatory death (DCD, group A) were used in 69 patients and liver grafts from donors after brain death (group B) were used in 265 patients.

RESULTS

No difference was found in terms of sex, body mass index, Model for End-Stage Liver Disease score, indication for transplantation, intensive care unit stay, and Child-Pugh score. The mean transfusion of hemoderivates was as follows: red blood cell 9 (0-28) units in group A vs 6 (0-20) units in group B (P = .004) and fresh frozen plasma 10 (0-29) units in group A vs 9.5 (0-23) in group B (P = .000). The only 2 factors related to massive blood transfusion (>6 units of red blood cell) were uncontrolled DCD condition (odds ratio = 2.38; 95% confidence interval, 1.32-4.31; P = .004), and higher Model for End-Stage Liver Disease score (odds ratio = 2.63; 95% confidence interval, 1.53-4.55; P = .001). Survival at 1, 3, and 5 years was 81.3%, 70.2%, and 68.9% in group A vs 89%, 83.7%, and 78% in group B (P = .070).

CONCLUSION

The use of liver grafts from DCDs is associated with increased necessity of transfusion of hemoderivates in comparison with the use of liver grafts from donors after brain death.

Preischemic transfusion of old packed RBCs exacerbates early-phase warm hepatic ischemia reperfusion injury in rats

BACKGROUND

Hepatic innate immune cells are considered to play a central role in the early phase of hepatic ischemia reperfusion (IR) injury. Transfusion of old red blood cells (RBCs) is known to prime immune cells, and transfusion before IR may exacerbate liver injury because of the expected hyperresponsiveness of immune cells.

MATERIALS AND METHODS

Twenty-four Sprague-Dawley rats were divided into four groups: sham operation (Sham); hepatic IR only (IR Control); and two transfusion groups, preischemic (Pre-T) and postischemic (Post-T), in which allogeneic RBCs stored for 2 weeks were transfused before hepatic IR or after reperfusion, respectively. Partial hepatic ischemia was induced for 90 min, and reperfusion was allowed for 120 min. Serum alanine transaminase levels, area of necrosis, and apoptotic cells were then assessed. Inflammatory (tumor necrosis factor alpha, interleukin 1 beta [IL-1β], IL-6, IL-10, and cyclooxygenase 2) and oxidative mediators (heme oxygenase 1, superoxide dismutase, and glutathione peroxidase 1) were assessed for elucidating the relevant mechanisms underlying the hepatic injury.

RESULTS

Pre-T, but not Post-T, showed increased serum alanine transaminase levels than IR Control (P < 0.05). Area of necrosis was more severe in Pre-T than in IR Control or Post-T (P < 0.01), and apoptotic cells were also more abundant in Pre-T than in IR Control (P < 0.01). tumor necrosis factor alpha and IL-6 levels were higher in Pre-T than in IR Control or Post-T (P < 0.05), with no significant difference in cytoprotective protein levels.

CONCLUSIONS

Preischemic transfusion of old RBCs aggravated hepatic injury. Inflammatory cytokines seemed to play a crucial role in liver injury exacerbation. Our results indicate that transfusion before hepatic ischemia may be detrimental.

Assessment of haemostasis in patients with cirrhosis: Relevance of the ROTEM tests?: A prospective, cross-sectional study

BACKGROUND

In patients with cirrhosis, decreased rotational thromboelastometry (ROTEM) parameters suggest hypocoagulability secondary to liver dysfunction. However, observed normal or increased thrombin generation suggests preserved haemostasis and/or a procoagulant state. The correlated levels of both coagulation factors and inhibitors also support preserved haemostasis.

OBJECTIVE

The objective of this study is to investigate the correlation between three specific approaches of haemostasis (ROTEM, thrombin generation and coagulation factors/inhibitors) on the same plasma sample from patients with cirrhosis.

DESIGN

A prospective, observational study.

SETTING

Single university hospital.

PARTICIPANTS

Forty patients with cirrhosis.

INTERVENTION

Measurement of the following factors: model for end-stage liver disease (MELD) scores; ROTEM maximum clot firmness (ROTEM-MCF) in EXTEM, INTEM, FIBTEM assays; fibrinogen; factors V and VIII; von Willebrand factor; protein C; protein S; antithrombin; and the thrombin generation test (TGT) enabling the calculation of endogenous thrombin potential without and with thrombomodulin, and the ratio of endogenous thrombin potential with-to-without thrombomodulin (regarded as an index of hypercoagulability).

RESULTS

ROTEM-MCF values were distributed within the normal and hypocoagulation ranges; were correlated to variations in factor V, fibrinogen, protein C and S and antithrombin; and were inversely correlated to MELD scores (ρ > 0.5; P < 0.05). Levels of von Willebrand factor were above normal and were not correlated with any other factor levels. After addition of thrombomodulin, endogenous thrombin potential values were distributed within or above normal values. Factor V variation was correlated to the ratio of endogenous thrombin potential with-to-without thrombomodulin.

CONCLUSION

ROTEM indicated hypocoagulability correlated to liver dysfunction. In contrast, the TGT indicated a preserved or even increased coagulation profile (which was supported by the correlation between coagulant factors and inhibitors) and a potential for hypercoagulability inversely correlated to the degree of liver dysfunction. ROTEM may not be appropriate for haemostasis assessment in patients with liver cirrhosis and could lead to the unnecessary transfusion of fresh frozen plasma.

TRIAL REGISTRATION

S.C. 3024 - ID RCB: 2012-A01728-35.

Reducing transfusion requirements in liver transplantation

Liver transplantation (LT) was historically associated with massive blood loss and transfusion. Over the past two decades transfusion requirements have reduced dramatically and increasingly transfusion-free transplantation is a reality. Both bleeding and transfusion are associated with adverse outcomes in LT. Minimising bleeding and reducing unnecessary transfusions are therefore key goals in the perioperative period. As the understanding of the causes of bleeding has evolved so too have techniques to minimize or reduce the impact of blood loss. Surgical “piggyback” techniques, anaesthetic low central venous pressure and haemodilution strategies and the use of autologous cell salvage, point of care monitoring and targeted correction of coagulopathy, particularly through use of factor concentrates, have all contributed to declining reliance on allogenic blood products. Pre-emptive management of preoperative anaemia and adoption of more restrictive transfusion thresholds is increasingly common as patient blood management (PBM) gains momentum. Despite progress, increasing use of marginal grafts and transplantation of sicker recipients will continue to present new challenges in bleeding and transfusion management. Variation in practice across different centres and within the literature demonstrates the current lack of clear transfusion guidance. In this article we summarise the causes and predictors of bleeding and present the evidence for a variety of PBM strategies in LT.