A comparison of transfusion requirements between living donation and cadaveric donation liver transplantation: relationship to model of end-stage liver disease score and baseline coagulation status

Preoperative fibrinogen level and blood transfusions in liver transplantation: A systematic review

BACKGROUND

Orthotopic liver transplantation (OLT) is a major surgery often associated with significant bleeding. We conducted a systematic review to explore the association between preoperative fibrinogen level and intraoperative blood products transfusion, blood loss and clinical outcomes in patients undergoing OLT.

METHODS

We included observational studies conducted in patients undergoing an OLT mostly for end-stage liver disease that reported an association between the preoperative fibrinogen level and our outcomes of interest. Our primary outcome was the intraoperative red blood cell (RBC) transfusion requirements. Our secondary outcomes were intraoperative blood loss, intraoperative transfusion of any blood product, postoperative RBC transfusion, postoperative thrombotic or hemorrhagic complications, and mortality. We used a standardized search strategy. We reported our results mostly descriptively but conducted meta-analyses using random-effect models when judged feasible.

RESULTS

We selected 24 cohort studies reporting at least one of our outcomes. We found that a high preoperative fibrinogen level was associated with fewer intraoperative RBC and other blood products transfusions, and lower blood loss. We also found a lower overall survival in patients with a higher fibrinogen level (pooled hazard ratio [95% CI] of 1.50 [1.23 to 1.84]; 5 studies, n = 1012, I2 = 48%). Only one study formally explored a fibrinogen level threshold effect. Overall, reporting was heterogeneous, and risk of bias was variable mostly because of uncontrolled confounding.

CONCLUSION

A higher preoperative fibrinogen level was associated with fewer intraoperative RBC and other blood products transfusions, lower blood loss, and higher mortality. Further studies may help clarify observed associations and inform guidelines.

Development of Machine Learning Models Predicting Estimated Blood Loss during Liver Transplant Surgery

The incidence of major hemorrhage and transfusion during liver transplantation has decreased significantly over the past decade, but major bleeding remains a common expectation. Massive intraoperative hemorrhage during liver transplantation can lead to mortality or reoperation. This study aimed to develop machine learning models for the prediction of massive hemorrhage and a scoring system which is applicable to new patients. Data were retrospectively collected from patients aged >18 years who had undergone liver transplantation. These data included emergency information, donor information, demographic data, preoperative laboratory data, the etiology of hepatic failure, the Model for End-stage Liver Disease (MELD) score, surgical history, antiplatelet therapy, continuous renal replacement therapy (CRRT), the preoperative dose of vasopressor, and the estimated blood loss (EBL) during surgery. The logistic regression model was one of the best-performing machine learning models. The most important factors for the prediction of massive hemorrhage were the disease etiology, activated partial thromboplastin time (aPTT), operation duration, body temperature, MELD score, mean arterial pressure, serum creatinine, and pulse pressure. The risk-scoring system was developed using the odds ratios of these factors from the logistic model. The risk-scoring system showed good prediction performance and calibration (AUROC: 0.775, AUPR: 0.753).

Perioperative management of adult living donor liver transplantation: Part 1 - recipients

Living donor liver transplantation was first developed to mitigate the limited access to deceased donor organs in Asia in the 1990s. This alternative liver transplantation option has become an established and widely practiced transplantation method for adult patients suffering from end-stage liver disease. It has successfully addressed the shortage of deceased donors. The Society for the Advancement of Transplant Anesthesia and the Korean Society of Transplant Anesthesia jointly reviewed published studies on the perioperative management of live donor liver transplant recipients. The review aims to offer transplant anesthesiologists and critical care physicians a comprehensive overview of the perioperative management of adult live liver transplantation recipients. We feature the status, outcomes, surgical procedure, portal venous decompression, anesthetic management, prevention of acute kidney injury, avoidance of blood transfusion, monitoring and therapeutic strategies of hemodynamic derangements, and Enhanced Recovery After Surgery protocols for liver transplant recipients. This article is protected by copyright. All rights reserved.

Changes in the allocation policy for deceased donor livers in Korea: perspectives from anesthesiologists

Background

The allocation policy for deceased donor livers in Korea was changed in June 2016 from Child-Turcotte-Pugh (CTP) scoring system-based to Model for End-stage Liver Disease (MELD) scoring system-based. Thus, it is necessary to review the effect of allocation policy changes on anesthetic management.

Methods

Medical records of deceased donor liver transplantation (DDLT) from December 2014 to May 2017 were reviewed. We compared the perioperative parameters before and after the change in allocation policy.

Results

Thirty-seven patients underwent DDLT from December 2014 to May 2016 (CTP group), and 42 patients underwent DDLT from June 2016 to May 2017 (MELD group). The MELD score was significantly higher in the MELD group than in the CTP group (36.5 ± 4.6 vs. 26.5 ± 9.4, P < 0.001). The incidence of hepatorenal syndrome was higher in the MELD group than in the CTP group (26 vs. 7, P < 0.001). Packed red blood cell transfusion occurred more frequently in the MELD group than in the CTP group (5.0 ± 3.6 units vs. 3.4 ± 2.2 units, P = 0.025). However, intraoperative bleeding, vasopressor support, and postoperative outcomes were not different between the two groups.

Conclusions

Even though the patient’s objective condition deteriorated, perioperative parameters did not change significantly.

Point-of-care haemostasis monitoring during liver transplantation is cost effective

Background Optimal haemostasis management in orthotropic liver transplant (OLT) could reduce blood loss and transfusion volume, improve patient outcomes and reduce cost. Methods We performed a study including 336 OLTs to evaluate the clinical and cost effectiveness of a new point-of-care (POC)-based haemostatic management approach in OLT patients. Results In terms of health benefit we found that the new approach showed a significant reduction in transfusion requirements (red blood cell transfusion units were reduced from 5.3±4.6 to 2.8±2.9 [p<0.001], free frozen plasma from 3.1±3.3 to 0.4±1.0 [p<0.001] and platelets from 2.9±3.9 to 0.4±0.9 [p<0.001], transfusion avoidance, 9.7% vs. 29.1% [p<0.001] and massive transfusion, 14.5% vs. 3.8% [p=0.001]); we also found a significant improvement in patient outcomes, such, reoperation for bleeding or acute-kidney-failure (8.3% vs. 2.4%, p=0.015; 33.6% vs. 5.4%, p<0.001), with a significant reduction in the length of the hospital total stay (40.6±13.8 days vs. 38.2±14.4 days, p=0.001). The lowest cost incurred was observed with the new approach (€73,038.80 vs. €158,912.90) with significant patient saving associated to transfusion avoidance (€1278.36), ICU-stay (€3037.26), total-stay (€3800.76) and reoperation for bleeding (€80,899.64). Conclusions POC haemostatic monitoring during OLT is cost effective.

Impact of MELD Score-Based Organ Allocation on Mortality, Bleeding, and Transfusion in Liver Transplantation: A Before-and-After Observational Cohort Study

OBJECTIVE

The goal of this study was to evaluate the effect of the Model for End-Stage Liver Disease (MELD)-based allocation system on mortality, bleeding, and transfusion requirement in orthotopic liver transplantation (OLT).

DESIGN

OLTs were studied for this observational study (before-and-after observational cohort study).

SETTING

One community hospital.

PARTICIPANTS

The study comprised 686 patients who underwent 750 consecutive OLTs.

INTERVENTION

None.

MEASUREMENTS AND MAIN RESULTS

Patients who underwent OLT in the MELD era had an adjusted lower 1-year mortality (adjusted odds ratio 0.45 [0.24-0.83]) compared with patients who underwent OLT the pre-MELD era. No significant difference in 1-month mortality was observed. Other variables with a significant effect on 1-year mortality in multivariate analysis were preoperative international normalized ratio, intraoperative use of a phlebotomy, total intraoperative volume of crystalloid infused, and retransplantation. Blood loss was greater in the MELD era (median difference 200 mL; p < 0.001), as were red blood cell, fresh frozen plasma, and cryoprecipitate transfusions. More patients in the MELD era received at least 1 transfusion (27% v 20%; p = 0.024).

CONCLUSION

The MELD allocation system did not affect 1-month mortality, but a decrease in 1-year mortality was demonstrated. Blood loss and transfusions increased during OLTs performed in the MELD era. The role of other variables should be explored further to explain postoperative morbidity and mortality.

The Coagulation Profile of End-Stage Liver Disease and Considerations for Intraoperative Management

The coagulopathy of end-stage liver disease results from a complex derangement in both anticoagulant and procoagulant processes. With even minor insults, cirrhotic patients experience either inappropriate bleeding or clotting, or even both simultaneously. The various phases of liver transplantation along with fluid and blood product administration may contribute to additional disturbances in coagulation. Thus, anesthetic management of patients undergoing liver transplantation to improve hemostasis and avoid inappropriate thrombosis in the perioperative environment can be challenging. To add to this challenge, traditional laboratory tests of coagulation are difficult to interpret in patients with end-stage liver disease. Viscoelastic coagulation tests such as thromboelastography (Haemonetics Corporation, Braintree, MA) and rotational thromboelastometry (TEM International, Munich, Germany) have helped to reduce transfusion of allogeneic blood products, especially fresh frozen plasma, but have also lead to the increased use of fibrinogen-containing products. In general, advancements in surgical techniques and anesthetic management have led to significant reduction in blood transfusion requirements during liver transplantation. Targeted transfusion protocols and pharmacologic prevention of fibrinolysis may further aid in the management of the complex coagulopathy of end-stage liver disease.

Risk factors for intraoperative massive transfusion in pediatric liver transplantation: a multivariate analysis

Background: Pediatric liver transplantation (LT) is strongly associated with increased intraoperative blood transfusion requirement and postoperative morbidity and mortality. In the present study, we aimed to assess the risk factors associated with massive transfusion in pediatric LT, and examined the effect of massive transfusion on the postoperative outcomes. Methods: We enrolled pediatric patients who underwent LT between December 1994 and June 2015. Massive transfusion was defined as the administration of red blood cells ≥100% of the total blood volume during LT. The cases of pediatric LT were assigned to the massive transfusion or no-massive transfusion (administration of red blood cells <100% of the total blood volume during LT) group. Univariate and multivariate logistic regression analyses were performed to evaluate the risk factors associated with massive transfusion in pediatric LT. Kaplan-Meier survival analysis, with the log rank test, was used to compare graft and patient survival within 6 months after pediatric LT between the 2 groups. Results: The total number of LT was 112 (45.0%) and 137 (55.0%) in the no-massive transfusion and massive transfusion groups, respectively. Multivariate logistic regression analysis indicated that high white blood cell (WBC) count, low platelet count, and cadaveric donors were significant predictive factors of massive transfusion during pediatric LT. The graft failure rate within 6 months in the massive transfusion group tended to be higher than that in the no-massive transfusion group (6.6% vs. 1.8%, P = 0.068). However, the patient mortality rate within 6 months did not differ significantly between the massive transfusion and no-massive transfusion groups (7.3% vs. 7.1%, P = 0.964). Conclusion: Massive transfusion during pediatric LT is significantly associated with a high WBC count, low platelet count, and cadaveric donor. This finding can provide a better understanding of perioperative blood transfusion management in pediatric LT recipients.

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.

Point-of-care haemostasis monitoring during liver transplantation reduces transfusion requirements and improves patient outcome

BACKGROUND

Optimal haemostasis management can improve patient outcomes and reduce blood loss and transfusion volume in orthotopic-liver-transplant (OLT).

METHODS

We performed a prospective study including 200 consecutive OLTs. The first 100 patients were treated according to the clinic's standards and the next 100 patients were treated using the new point-of-care (POC)-based haemostasis management strategy. Transfusion parameters and other outcomes were compared between groups.

RESULTS

Transfusion requirements were reduced in the POC group. The median and IQR of red-blood-cells (RBC) transfusion units were reduced from 5 [2-8] to 3 [0-5] (p < 0.001), plasma from 2 [0-4] to 0 (p < 0.001), and platelets from 1 [0-4] to 0 [0-1] (p < 0.001), into the POC group only four patients received tranexamic acid and fibrinogen transfusion rate was 1.13 ± 1.44 g (p = 0.001). We also improved the incidence of transfusion avoidance, 5% vs. 24% (p < 0.001) and reduced the incidence of massive transfusion (defined as the transfusion of more than 10 RBC units), 13% vs. 2% (p = 0.005). We also observed a relationship between RBC transfusion requirements and preoperative haemoglobin, and between platelet transfusion and preoperative fibrinogen levels. The incidence of postoperative complications, such as, reoperation for bleeding, acute-kidney-failure or haemodynamic instability was significantly lower (13.0% vs. 5%, p = 0.048, 17% vs. 2%, p < 0.001, and 29% vs. 16%, p = 0.028). Overall, blood product transfusion was associated with increased risk of postoperative complications.

CONCLUSIONS

A haemostatic therapy algorithm based on POC monitoring reduced transfusion and improved outcome in OLT.

Aminocaproic Acid (amicar) as an alternative to aprotinin (trasylol) in liver transplantation

INTRODUCTION

This study compared clinical outcomes for a large number of liver transplant patients receiving intraoperative epsilon-aminocaproic acid (EACA), aprotinin, or no antifibrinolytic agent over an 8-year period.

PATIENTS AND METHODS

Records for deceased donor liver transplants were reviewed. Data included antifibrinolytic agent, blood loss, early graft function, and postoperative complications. Study groups included low-dose aprotinin, high-dose aprotinin, EACA (25 mg/kg, 1-hour infusion), or no antifibrinolytic agent.

RESULTS

Data were included for 1170 consecutive transplants. Groups included low-dose aprotinin (n = 324 [28%]), high-dose aprotinin (n = 308 [26%]), EACA (n = 216 [18%]), or no antifibrinolytic (n = 322 [28%]). EACA had the lowest intraoperative blood loss and required the fewest transfusions of plasma. Patients receiving no agent required the most blood transfusions. Early graft loss was lowest in the EACA group, and 90-day and 1-year patient survival rates were significantly higher for the low-dose aprotinin and EACA groups according to Cox regression. Complications were similar, but there were more episodes of deep vein thrombosis in patients receiving EACA.

CONCLUSIONS

These results suggest that transitioning from aprotinin to EACA did not result in worse outcomes. In addition to decreased intraoperative blood loss, a trend toward improved graft and patient survival was seen in patients receiving EACA.

Impact of Model for End-Stage Liver Disease score on transfusion rates in liver transplantation

BACKGROUND

Liver transplantation (OLT) can entail a high risk of blood loss requiring transfusions, which increase morbidity and mortality. In recent years many efforts have been spent to improve the surgical and anesthetic management to decrease transfusion rates during OLT. Preoperative predictors for transfusion in OLT, remain uncertain.

METHODS

We retrospectively reviewed the 219 OLT performed from 2005 to 2011 focusing on blood product (BP) transfusions. Statistical analysis sought the impact of transfusions on OLT outcomes to identify possible independent predictors of higher BP requirements.

RESULTS

The 1- and 3-year survival rates were 86.6% and 76.45% for patients and 81.0% and 71.8% for grafts respectively. The mean intra- and perioperative red blood cell (RBC) transfusion rates were 12.3 ± 11.7 U and 15.5 ± 13.0 U respectively. A statistical analysis demonstrated a significant influence of BP transfusion on post-OLT complications and survivals. Multivariate logistic regression analysis showed the Model for End-Stage Liver Disease (MELD) score to be the only independent predictor of perioperative RBC transfusions.

CONCLUSIONS

Our results confirmed the link between intra- and perioperative transfusions and outcome of OLT patients. MELD score resulted the only independent variable associated with increased perioperative RBC transfusions.

Single-center transfusion rate for 555 consecutive liver transplantations: impact of two eras

Orthotopic liver transplantation (OLT) is the treatment of choice for patients with acute or chronic end-stage liver disease, irresectable primary liver tumor, and metabolic disorders. Historically, OLT has been associated with considerable blood loss and the need for transfusions. However, over the years there has been reduction is need for blood products. The aim of this article was to compare two distinct eras for perioperative blood transfusion rate among patients undergoing OLT; Era I, 200 transplantations in 188 patients, and Era II, 355 transplantations in 339 patients. The donor mean age was 33.70 (Era I) versus 35.34 (Era II). Cause of death in both eras was traumatic brain injury followed by cerebral vascular accident. Organ recipient data showed a mean age of 48.87 (Era I) versus 46.49 (Era II). During Era I patients with Child B (56.8%) prevailed, followed by Child C (35.4%) and Child A (7.8%). In Era II also patients with Child B (53.1%) prevailed, followed by Child C (39.6%) and Child A (7.3%). The prevalence of hepatocellular carcinoma (HCC) during Era I was 9% (18) and in Era II 20% (71). The use of blood products in the perioperative period: was as follows packed red blood cells 1.76 (Era I) versus 0.57 (Era II) units; fresh frozen plasma 1.89 (Era I) versus 0.49 (Era II) units; platelets 2.16 (Era I) versus 0.28 (Era II) units; and cryoprecipitate 0.08 (Era I) versus 0.03 (Era II) units. OLT using the piggyback technique was performed with a transfusion rate below <30%, and it reduced blood loss and prevented severe hemodynamic instability.

Preoperative variables associated with transfusion requirements in orthotopic liver transplantation

BACKGROUND

Patients with end-stage chronic liver disease (CLD) and submitted to orthotopic liver transplantation (OLT) usually require blood transfusion during the procedure or in the post-operative period due to hemorrhage. Risk factors for transfusion need are not fully known. This study aimed to identify the factors associated with blood components requirements.

METHODS

In this retrospective study a total of 166 consecutive patients submitted to OLT with the piggyback technique, between 2001 and 2011, were evaluated for number of blood components transfused during surgical procedure and the four subsequent days (total of 5 days). We evaluated the association between the number of units transfused and clinical variables, such as: Child-Turcotte-Pugh (CTP) and MELD scores, hemoglobin concentration (Hb), INR, serum creatinine, bilirubin and albumin concentrations, and total, hypothermic and normothermic time of graft ischemia.

RESULTS

152 (91.6%) Patients were transfused (median of 24 units of blood components). Risk factors for higher blood transfusion requirements were CTP, INR, Hb and total time of graft ischemia. The group with CTP-A score received less blood components than CTP-B/C (11.5 vs 27; P=0.002). The group with Hb<10 required a higher number of blood units (34.5 vs 23; P=0.003). The group with INR<1.5 received less blood units (20.5 vs 31; P=0.012). The group transplanted with a graft exposed to less than the median of 555 min of ischemia received less transfusion (21 vs 27; P=0.03). MELD score and the other factors were not associated with blood requirements.

CONCLUSION

These results demonstrate that CTP, but not MELD score, hemoglobin concentration, INR, and total time of graft ischemia are preoperative variables associated with blood requirements during OLT and in the subsequent days.

Preoperative predictors of blood component transfusion in living donor liver transplantation

Context:

Extensive bleeding associated with liver transplantation is a major challenge faced by transplant surgeons, worldwide.

Aims:

To evaluate the blood component consumption and determine preoperative factors that predict the same in living donor liver transplantation (LDLT).

Settings and Design:

This prospective study was performed for a 1 year period, from March 2010 to February 2011.

Materials and Methods:

Intra- and postoperative utilization of blood components in 152 patients undergoing LDLT was evaluated and preoperative patient parameters like age, gender, height, weight, disease etiology, hemoglobin (Hb), hematocrit (Hct), platelet count (Plt), total leukocyte count (TLC), activated partial thromboplastin time (aPTT), international normalized ratio (INR), serum bilirubin (T. bilirubin), total proteins (T. proteins), albumin to globulin ratio (A/G ratio), serum creatinine (S. creatinine), blood urea (B. urea), and serum electrolytes were assessed to determine their predictive values. Univariate and stepwise discriminant analysis identified those factors, which could predict the consumption of each blood component.

Results:

The average utilization of packed red cells (PRCs), cryoprecipitates (cryo), apheresis platelets, and fresh frozen plasma was 8.48 units, 2.19 units, 0.93 units, and 2,025 ml, respectively. Disease etiology and blood component consumption were significantly correlated. Separate prediction models which could predict consumption of each blood component in intra and postoperative phase of LDLT were derived from among the preoperative Hb, Hct, model for end-stage liver disease (MELD) score, body surface area (BSA), Plt, T. proteins, S. creatinine, B. urea, INR, and serum sodium and chloride.

Conclusions:

Preoperative variables can effectively predict the blood component requirements during liver transplantation, thereby allowing blood transfusion services in being better prepared for surgical procedure.

Intraoperative predictors of short-term mortality in living donor liver transplantation due to acute liver failure

BACKGROUND

Acute liver failure (ALF) is a rare and fatal disease with rapidly deteriorating clinical features. Many predictive models for ALF outcomes have been tested, but none have been adopted as definitive guidelines for prognosis because of inconsistencies in accuracy. Most prognostic models for ALF are based on preoperative patient conditions, thus ignoring various specific intraoperative features relevant to postoperative outcomes. We investigated whether intraoperative factors predicted short-term mortality due to ALF in living donor liver transplantations (LDLT).

METHODS

We retrospectively collected intraoperative data, including surgical time, fluctuations in mean blood pressure (MBP) and heart rate, mean pulmonary arterial pressure (PAP), central venous pressure (CVP), urine output, laboratory data, oxygen indices (PaO(2)/FiO(2)), administered drugs, and transfusion of packed red blood cells (PRBCs) from 101 patients with ALF who underwent LDLT. After simple relationships of individual intraoperative variables with 1-month posttransplant mortality were analyzed, we examined potentially significant intraoperative variables (P < .10) by a multivariate adjustment process with preoperative indicators of ALF prognosis.

RESULTS

Intraoperative MBP fluctuations, first mean PAP and CVP, last oxygen index, administered calcium chloride, and PRBC transfusion showed individual associations with posttransplant mortality of ALF patients (P < .05). After multivariate adjustment, PRBC transfusion of ≥ 10 pints (odds ratio 4.73; 95% confidence interval [CI] 1.06-21.16) and MBP fluctuations (odds ratio 1.26; 95% CI 1.00-1.58) were identified to be independent predictors of 1-month posttransplant mortality, together with preoperative factors, including severe hepatic encephalopathy, and a Model for End-stage Liver Disease score ≥ 30 points (area under the curve 0.82, P < .001).

CONCLUSION

MBP fluctuations and large blood transfusions were intraoperative predictors of short-term mortality after LDLT due to ALF. Increased attention to intraoperative manifestations should provide valuable prognostic information for ALF.

Does the model for end-stage liver disease score predict transfusion amount, acid-base imbalance, haemodynamic and oxidative abnormalities during living donor liver transplantation?

The model for end-stage liver disease (MELD) score is associated with the severity of liver failure in transplant patients. This study examined whether life-threatening stress factors during liver transplantation differed according to the patients' preoperative MELD scores. Forty-four patients who underwent living donor liver transplantation were divided into a high MELD group (MELD score ≥ 20) (n = 25) and a low MELD group (MELD score < 20) (n = 19). The volume of blood components transfused, acid-base homeostasis variables, and haemodynamic and oxidative variables were measured at each stage of the surgery. The systemic vascular resistance index was significantly lower in the high MELD group than in the low MELD group at all time points. The oxygen utility index and the oxygen extraction ratio were all significantly lower in the high MELD group than in the low MELD group only at the preanhepatic stage and not at later stages of surgery. Intraoperative transfusion volume and the severity of metabolic acidosis were not associated with the preoperative MELD score.

Outcomes of patients with benign liver diseases undergoing living donor versus deceased donor liver transplantation

BACKGROUND/AIMS

The number of people undergoing living donor liver transplantation (LDLT) has increased rapidly in many transplant centres. Patients considering LDLT need to know whether LDLT is riskier than deceased donor liver transplantation (DDLT). The aim of this study was to compare the outcomes of patients undergoing LDLT versus DDLT.

METHODS

A total of 349 patients with benign liver diseases were recruited from 2005 to 2011 for this study. LDLT was performed in 128 patients, and DDLT was performed in 221 patients. Pre- and intra-operative variables for the two groups were compared. Statistically analysed post-operative outcomes include the postoperative incidence of complication, biliary and vascular complication, hepatitis B virus (HBV) recurrence, long-term survival rate and outcomes of emergency transplantation.

RESULTS

The waiting times were 22.10±15.31 days for the patients undergoing LDLT versus 35.81±29.18 days for the patients undergoing DDLT. The cold ischemia time (CIT) was 119.34±19.75 minutes for the LDLT group and 346±154.18 for DDLT group. LDLT group had higher intraoperative blood loss, but red blood cell (RBC) transfusion was not different. Similar ≥ Clavien III complications, vascular complications, hepatitis B virus (HBV) recurrence and long-term survival rates were noted. LDLT patients suffered a higher incidence of biliary complications in the early postoperative days. However, during the long-term follow-up period, biliary complication rates were similar between the two groups. The long-term survival rate of patients undergoing emergency transplantation was lower than of patients undergoing elective transplantation. However, no significant difference was observed between emergency LDLT and emergency DDLT.

CONCLUSIONS

Patients undergoing LDLT achieved similar outcomes to patients undergoing DDLT. Although LDLT patients may suffer a higher incidence of early biliary complications, the total biliary complication rate was similar during the long-term follow-up period.

[Association between the use of blood components and the five-year mortality after liver transplant]

BACKGROUND AND OBJECTIVES

Liver transplant (LT) surgery is associated with significant bleeding in 20% of cases, and several authors have demonstrated the risks related to blood components. The objective of the present study was to evaluate the impact of using blood components during hospitalization in five-year survival of patients undergoing LT.

METHODS

One hundred and thirteen patients were evaluated retrospectively. Several variables, including the use of blood components intraoperatively and throughout hospitalization, were categorized and evaluated by univariate analysis using Fisher's test. A level of significance of 5% was adopted. Results with p < 0.2 underwent multivariate analysis using multinomial logistic regression.

RESULTS

Parenchymal diseases, preoperative renal dysfunction, and longer stay in hospital and ICU are associated with greater five-year mortality after LT (p < 0.05). Unlike the intraoperative use of blood components, the accumulated transfusion of packed red blood cell, frozen fresh plasma, and platelets during the entire hospitalization was associated with greater five-year mortality after liver transplantation (p < 0.01).

CONCLUSIONS

This study emphasizes the relationship between the use of blood components during hospitalization and increased mortality in five years after LT.

Predictors of high intraoperative blood loss derived by simple and objective method in adult living donor liver transplantation

We conducted a risk factor analysis for high intraoperative blood loss (IBL) in 555 living donor liver transplantation (LDLT) cases with a simple and objective method of IBL estimation based on the concept of red cell mass (RCM): Lost RCM (mL) = patient's estimated blood volume (mL) × (preoperative hematocrit in % - postoperative hematocrit in %) + (transfused leukocyte-depleted red blood cell in units × 213 × 70%) + (transfused Cell Saver blood in mL × 55%). Analysis of 33 preoperative variables revealed that Model for End-stage Liver Disease (MELD) score, albumin, the presence of ascites, and previous abdominal surgery were correlated with high IBL (lost RCM > 1000 mL) in multivariate logistical regression analysis. In conclusion, we found that MELD score, albumin, the presence of ascites, and previous abdominal surgery were significantly correlated with high IBL during adult LDLT.

Effects of low central venous pressure during preanhepatic phase on blood loss and liver and renal function in liver transplantation

BACKGROUND

Although the low central venous pressure (LCVP) technique is used to decrease blood loss during liver resection, its efficacy and safety during transplant procedures are still debatable. Our study aimed to assess the effects of this technique and its clinical safety for recipients undergoing liver transplantation.

METHODS

Eighty-six adult patients were randomly divided into a LCVP group and a control group. In the LCVP group, CVP was maintained below 5 mmHg or 40% lower than baseline during the preanhepatic phase by limiting infusion volume, manipulating the patient's posture, and administration of somatostatin and nitroglycerine. Recipients in the control group received standard care. Hemodynamics, blood loss, liver function, and renal function of the two groups were compared perioperatively.

RESULTS

A lower CVP was maintained in the LCVP group during the preanhepatic phase, resulting in a significant decrease in blood loss (1922 +/- 1429 vs. 3111 +/- 1833 ml, P < 0.05) and transfusion volume (1200 +/- 800 vs. 2400 +/- 1200 ml, P < 0.05) intraoperatively. Compared with the control group, the LCVP group had a significantly lower mean arterial pressure at 2 h after the start of the operation (74 +/- 11 vs. 84 +/- 14 mmHg, P < 0.05), a lower lactate value at the end of the operation (5.9 +/- 3.0 vs. 7.2 +/- 3.0 mmol/l, P < 0.05), and a better preservation of liver function after the declamping of the portal vein. There were no significant differences in perioperative renal function and postoperative complications between the groups.

CONCLUSIONS

The LCVP technique during the preanhepatic phase reduced intraoperative blood loss, protected liver function, and had no detrimental effects on renal function in LT.

Model for end-stage liver disease score predicts left ventricular assist device operative transfusion requirements, morbidity, and mortality

BACKGROUND

The Model for End-Stage Liver Disease (MELD) predicts events in cirrhotic subjects undergoing major surgery and may offer similar prognostication in left ventricular assist device candidates with comparable degrees of multisystem dysfunction.

METHODS AND RESULTS

Preoperative MELD scores were calculated for subjects enrolled in the University of Michigan Health System (UMHS) mechanical circulatory support database. Univariate and multiple regression analyses were performed to investigate the ability of patient characteristics, laboratory data (including MELD scores), and hemodynamic measurements to predict total perioperative blood product exposure and operative mortality. The ability of preoperative MELD scores to predict operative mortality was evaluated in subjects enrolled in the Interagency Registry of Mechanically Assisted Circulatory Support (INTERMACS), and results were compared with those from the UMHS cohort. The mean+/-SD MELD scores for the UMHS (n=211) and INTERMACS (n=324) cohorts were 13.7+/-6.1 and 15.2+/-5.8, respectively, with 29 (14%) and 19 (6%) perioperative deaths. In the UMHS cohort, median total perioperative blood product exposure was 74 units (25th and 75th percentiles, 44 and 120 units). Each 5-unit MELD score increase was associated with 15.1+/-3.8 units (beta+/-SE) of total perioperative blood product exposure. Each 10-unit increase in total perioperative blood product exposure increased the odds of operative death (odds ratio, 1.05; 95% confidence interval, 1.01 to 1.10). Odds ratios, measuring the ability of MELD scores to predict perioperative mortality, were 1.5 (95% confidence interval, 1.1 to 2.0) and 1.5 (95% confidence interval, 1.1 to 2.1) per 5 MELD units for the UMHS and INTERMACS cohorts, respectively. When MELD scores were dichotomized as >or=17 and <17, risk-adjusted Cox proportional-hazard ratios for 6-month mortality were 2.5 (95% confidence interval, 1.2 to 5.3) and 2.5 (95% confidence interval, 1.1 to 5.4) for the UMHS and INTERMACS cohorts, respectively.

CONCLUSIONS

The MELD score identified left ventricular assist device candidates at high risk for perioperative bleeding and mortality.

MELD score and blood product requirements during liver transplantation: no link

BACKGROUND

Orthotopic liver transplantation has been traditionally associated with major blood loss and the need for allogenic blood product transfusions. In recent years, improvements in surgical and anesthetic techniques have greatly decreased the amount of blood products transfused. We have published a median of 0 for all intraoperative blood products transfused. Some authors argue that these results could be possible merely because of the relatively healthy cohort in terms of model of end-stage liver disease (MELD) score. The MELD score could be adjusted by some conditions (hepatocellular carcinoma, hemodialysis, hepatopulmonary syndrome, and amyloidosis) and was not adjusted in these series. The goal of this work was to verify the MELD score according to US standards and to find any link between the MELD score and the transfusion rate.

METHOD

Three hundred fifty consecutive liver transplantations were studied. The MELD score was adjusted according to US standards. Patients were divided into two groups according to the median of the MELD score. Blood loss and transfusion rate were determined for these two groups. Logistic regression models were used to find any link with transfusion of red blood cell (RBC) units.

RESULT

The MELD score before adjusting was 19+/-9 and 22+/-10 after. A mean of 0.5+/-1.3 RBC units/patient intraoperative were transfused with 80.6% of cases without any blood products. There was no difference for the blood loss (999+/-670 mL vs. 1017+/-885 mL) or the transfusion rate (0.4+/-1.2 vs. 0.5+/-1.4 RBC/patient) between two groups of MELD (<21 or >or=21) or any of its component (creatinine, bilirubin, and international normalized ratio). The logistic regression analysis found that only two variables were linked to RBC transfusion; starting hemoglobin value and phlebotomy.

CONCLUSION

In this series, the MELD score was as high as US series and did not predict blood losses and blood product requirement during liver transplantation. If the MELD system has to be implemented to prioritize orthotopic liver transplantation, it should be revisited, and the starting hemoglobin value should be added to the equation.

The changing face of patients presenting for liver transplantation

PURPOSE OF REVIEW

Significant changes have been witnessed recently in patients presenting for liver transplantation. The growing number of liver transplantations performed, the increasingly successful outcomes, the expansion of indications, and the implementation of the Model for End-Stage Liver Disease (MELD) system are driving forces for those changes. The purpose of this review is to examine those changes and their effect in perioperative management.

RECENT FINDINGS

Patients who present for liver transplantation today have higher MELD scores and more advanced liver disease. Studies show that high MELD score patients are associated with high perioperative risks and undergo a more difficult perioperative course than patients with low MELD score. More specifically, they have more preoperative comorbidities, more baseline laboratory abnormalities, and higher requirements for intraoperative transfusion and vasopressors. Progress has been also made in management in patients with hepatocellular carcinoma, fulminant hepatic failure, and coronary artery disease prior to liver transplantation.

SUMMARY

Patients who present for liver transplantation today are more acutely ill compared with a few years ago and have more comorbidities, higher perioperative risks, and a more difficult perioperative course. Further characterization of the changes and associated perioperative risks and strategies to manage those risks are needed.

Changing trends in transfusion practice in liver transplantation

PURPOSE OF REVIEW

Prevention of excessive blood loss is an important issue in the perioperative management of liver transplantation. This review describes changing trends in blood products use, risk predicting of blood transfusion, variability in use and practices, as well as transfusion safety during liver transplantation.

RECENT FINDINGS

Over the last 20 years, the average use of blood products per case has considerably decreased. There are marked interinstitutional differences in blood use. Differences in patient population characteristics and surgical techniques are a partial explanation, but differences in transfusion practices probably account for a substantial part of the variability. Recent data have sparked off ongoing controversy relating to volume replacement therapy and its impact on blood loss. New studies emphasize the risks associated with transfusion in liver transplantation.

SUMMARY

Recent studies call for continuing every reasonable effort to minimize the use of blood components and can guide us in new approaches to this vital problem.

Predictors of blood product use in orthotopic liver transplantation using the piggyback hepatectomy technique

Orthotopic liver transplantation (OLT) has historically been associated with massive blood loss and hemodynamic instability related to the coexistence of varices, coagulopathy, thrombocytopenia, and portal hypertension. Piggyback hepatectomy (PGB) is a technique increasingly utilized in OLT to avoid veno-venous bypass and vena cava clamping. This study evaluated the factors associated with blood loss and blood product requirement in PGB.

METHODS

This study is a retrospective review of the anesthesia preoperative and operative notes and computerized lab values for all adult cadaveric liver transplants over a 42-month period. These data were combined with the liver transplant database for analysis. Approximately 98% of the transplants were performed using a standard piggyback approach with no use of veno-venous bypass.

RESULTS

Data were included for all 526 transplants performed during this time period. Estimated blood loss (EBL) was 1000 cc. Median transfusion requirement was 3 units packed red blood cells, 7 units fresh frozen plasma, and 6 units platelets. Multivariate linear regression demonstrated that predictors of EBL were age, MELD score, preoperative hemoglobin, initial fibrinogen, initial central venous pressure, and total anesthesia time. Predictors of PRBC useage were age, MELD score, preoperative hemoglobin, initial fibrinogen, and anesthesia time. Postoperatively increased transfusion requirement was associated with increased length of hospital stay and lower 90-day and 1-year graft and patient survivals.

CONCLUSION

These results demonstrate that PGB can be safely accomplished in nearly all liver transplant patients without venovenous bypass or vena cava clamping and with less warm ischemia, which may ultimately be associated with less perioperative morbidity and improved outcomes.

A comparison of the Thrombelastograph and the ROTEM

Elastic modulus-based assessment of hemostasis in clinical and research settings has been conducted for nearly 60 years. Two systems utilizing this technology include the Thrombelastograph (Haemoscope Corporation, Niles, Illinois, USA) and the ROTEM (Pentapharm GmbH, Munich, Germany). The study goal was to compare the Thrombelastograph and the ROTEM to determine whether differences in data could be detected. Plasma (n = 8 per condition) was not activated (native); was celite-activated, hypocoagulable by dilution with hydroxyethyl starch; was celite-activated, normal; and was celite-activated, hypercoagulable by addition of fibrinogen. Equivalent ratios of plasma mixture to CaCl2 were maintained between the Thrombelastograph and ROTEM systems. Data collected included the reaction time, angle, maximum amplitude and maximum elastic modulus. The ROTEM system generated significantly (P<0.05) smaller reaction time (mean +/- SD, 459 +/- 39 versus 788 +/- 94 s) and greater angle (60.1 +/- 5.3 versus 46.4 +/- 4.6 degrees ), maximum amplitude (27.6 +/- 1.6 versus 24.4 +/- 1.4 mm) and maximum elastic modulus (1911 +/- 152 versus 1616 +/- 121 dynes/cm2) values with native plasma compared with the Thrombelastograph. Celite-activation tended to attenuate differences between the two systems. In conclusion, a comparison of the Thrombelastograph and the ROTEM with similar samples demonstrated clinically significant differences in the data generated without exogenous activation. Given these data and the differences in proprietary activator, divergent results are expected, perhaps affecting clinical decision-making.

Evaluation of cell salvage autotransfusion utility during liver transplantation

BACKGROUND

Orthotopic liver transplantation (OLT) may be associated with massive blood loss and the need for allogenic blood product transfusions. Cell salvage autotransfusion (CS) is an attractive alternative to allogenic red blood cell (RBC) transfusion. However, controversy surrounds its usefulness during OLT; some studies stated that CS decreased transfusions of allogenic blood products and others stated that blood loss was increased. The aim of this study was to evaluate the efficiency of the CS during OLT.

PATIENTS AND METHODS

After approval by the institutional ethics committee, a prospective survey was undertaken. A total of 150 consecutive OLTs were included in the study. Two groups of patients were formed. Period 1 included patients 1-75 with no CS use. Period 2 comprised patients 76-150 with systematic CS use.

RESULTS

Patients from both periods were comparable. CS was used in all cases in period 2, and there was enough salvaged blood to retransfuse 65% of these OLTs. The mean volume of retransfused blood was 338+/-339 ml. The transfusion rate did not change from period 1 to period 2. The mean number of RBC units transfused per patient was 0.4+/-0.9 vs 0.4+/-1.2 with 78.7% vs 81.3% of cases not receiving transfusion of any blood product. The threshold for RBC transfusions was the same. The length of surgery and blood loss were greater in period 2 than in period 1 (associated with the arrival of two junior surgeons), but the hemoglobin (Hb) value was also higher at the end of surgery (93.8+/-19.3 g/L vs 85.2+/-17.8 g/L, p<0.0001).

CONCLUSION

Despite increased blood loss in period 2, CS saved 21 g/L of Hb per patient or two RBC unit transfusions. As long as we cannot predict with accuracy which patients will bleed, we will continue to use the CS for all OLTs.

Preoperative characteristics and intraoperative transfusion and vasopressor requirements in patients with low vs. high MELD scores

Recent changes in organ allocation based on the model for end-stage liver disease (MELD) prioritize the most ill patients on the waiting list for liver transplantation. While patients undergoing liver transplantation in the MELD era are more acutely ill, the impact of the policy changes on perioperative management has not been completely assessed. We retrospectively reviewed the records of 124 primary adult liver transplant patients. Patients were divided into low (< or = 30) and high MELD (>30) score groups. Preoperative characteristics and intraoperative management were compared between the 2 groups. Patients with high MELD scores had lower baseline hematocrit and fibrinogen levels and were more likely to require ventilatory and vasopressor support before transplantation. Intraoperative transfusion requirements and use of vasopressors were also significantly increased in patients with high MELD scores compared to patients with low MELD scores. In conclusion, these data suggest that pretransplant MELD scores provide important information for perioperative management of patients undergoing liver transplantation.