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

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.

Pleural Effusion and Malnutrition Are Associated With Worse Early Outcomes After Liver Transplant

INTRODUCTION

Pulmonary complications after liver transplantation (LT) have previously been associated with longer hospital stays and ventilator time, and higher mortality. This study reports the outcomes for a specific pulmonary complication, pleural effusion, in LT recipients.

METHODS

Records from a single transplant center were analyzed retrospectively for all adult LT patients. Patients with documented pleural effusion by radiographic imaging within 30 days pre- or post-transplant were considered as cases. Outcomes included length of hospital stay, discharge disposition, hospital readmission, discharge with home oxygen, and 1-year survival.

RESULTS

During the 4-year study period, 512 LTs were performed, with 107 patients (21%) developing a peri-transplant pleural effusion. In total, 49 patients (10%) had a pre-transplant effusion, 91 (18%) had a post-transplant effusion, and 32 (6%) had both. Characteristics associated with the presence of any pleural effusion included an increasing model for end-stage liver disease score, re-transplantation, diagnosis of alcoholic liver disease, low protein levels, and sarcopenia. Effusion patients had longer hospital stays (17 vs 9 days, P < .001) and higher likelihood of discharge to a care facility (48% vs 21%, P < .001). Ninety-day readmission occurred in 69% of effusion patients (vs 44%, P < .001). One-year patient survival with any effusion was 86% (vs 94%, P < .01).

CONCLUSIONS

Overall, 21% of recipients developed a clinically significant peri-transplant pleural effusion. Pleural effusion was associated with worse outcomes for all clinical measures. Risk factors for the development of pleural effusion included higher MELD score (>20), re-transplantation, alcoholic liver disease, and poor nutrition status, including poor muscle mass.

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.

Contribution of Salvaged Blood Red Blood Cell Transfusion During Living Donor Liver Transplantation

BACKGROUND

Transfusion of allogeneic blood products can have adverse effects and profoundly influence postoperative liver transplantation outcomes, including graft survival. To minimize allogeneic red blood cell (RBC) transfusion, salvaged blood can be used during liver transplantation. The aim of this study was to determine the contribution of salvaged blood to allogeneic RBC transfusion in living donor liver transplantation (LDLT) recipients.

METHODS

Data of 311 adult-to-adult LDLT recipients between January 2015 and April 2019 were analyzed. The primary outcome was a change in requirement for allogeneic RBCs due to the use of salvaged blood. Additionally, predictors of intraoperative allogeneic RBC transfusion were investigated.

RESULTS

One hundred fifty-three (49.2%) recipients required allogeneic RBC transfusion. If recipients did not receive salvaged blood, 253 (81.4%) recipients would have needed allogeneic RBC transfusion. The total volume of salvaged blood transfused into recipients during surgery was 269,165 mL, which corresponded to 993 units of allogeneic RBCs and accounted for 76.1% of total RBC transfusion volume. Multivariate analysis showed that male recipients, model for end-stage liver disease score, preoperative hemoglobin level, and volume of salvaged blood used during surgery were independent predictors of the need for intraoperative allogenic RBC transfusion.

CONCLUSIONS

Intraoperative use of salvaged blood significantly reduced allogeneic RBC transfusion in LDLT recipients. It can help transplant teams manage transfusion of allogeneic RBCs during liver transplantation.

Blood products and liver transplantation: A strategy to balance optimal preparation with effective blood stewardship

BACKGROUND

Unanticipated transfusion requirements during liver transplantation can delay lifesaving intraoperative resuscitation and strain blood bank resources. Risk-stratified preoperative blood preparation can mitigate these deleterious outcomes.

STUDY DESIGN AND METHODS

A two-tiered blood preparation protocol for liver transplantation was retrospectively evaluated. Eleven binary variables served as criteria for high-risk (HR) allocation. Primary outcomes included red blood cell (RBC), plasma (FFP), and platelet (Plt) utilization. Secondary outcomes included product under- and overpreparation. Contingency tables for transfusion requirements above the population means were generated using 15 clinical variables. Modified protocols were developed and retrospectively optimized using the study population.

RESULTS

Of 225 recipients, 102 received HR preoperative orders, which correlated to higher intraoperative transfusion requirements. However, univariate analysis identified only two statistical risk factors per product: Hgb ≤7.8 g/dl (p < .001) and MELD ≥38 (p = .035) for RBCs, Hgb ≤7.8 g/dl (p = .002) and acute alcoholic hepatitis (p = 0.015) for FFP, and Hgb ≤7.8 g/dl (p = .001) and normothermic liver preservation (p = .037) for Plts. Based on these findings, we developed modified protocols for individual products, which were evaluated retrospectively for their effectiveness at reducing under-preparatory events while limiting product overpreparation. Cohort statistics were used to define the preparation strategy for each protocol. Retrospective comparative analysis demonstrated the superiority of the modified protocols by improving the under-preparation rate from 24% to <10% for each product, which required a 1.56-fold and 1.44-fold increase in RBC and FFP overpreparation, respectively. Importantly, there was no difference in Plt overpreparation.

DISCUSSION

We report translatable data-driven blood bank preparation protocols for liver transplantation.

Which cava anastomotic techniques are optimal regarding immediate and short-term outcomes after liver transplantation: A systematic review of the literature and expert panel recommendations

BACKGROUND

It has long been debated whether cava anastomosis should be performed with the piggyback technique or cava replacement, with or without veno-venous bypass (VVB), with or without temporary portocaval shunt (PCS) in the setting of liver transplantation.

OBJECTIVES

To identify whether different cava anastomotic techniques and other maneuvers benefit the recipient regarding short-term outcomes and to provide international expert panel recommendations.

DATA SOURCES

Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central.

METHODS

A systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel (CRD42021240979).

RESULTS

Of 3205 records screened, 307 publications underwent full-text assessment for eligibility and 47 were included in qualitative synthesis. Four studies were randomized control trials. Eighteen studies were comparative. The remaining 25 were single-center retrospective noncomparative studies.

CONCLUSION

Based on existing data and expert opinion, the panel cannot recommend one cava reconstruction technique over another, rather the surgical approach should be based on surgeon preference and center dependent, with special consideration toward patient circumstances (Quality of evidence: Low | Grade of Recommendation: Strong). The panel recommends against routine use of vevo-venous bypass (Quality of evidence: Very Low | Grade of Recommendation: Strong) and against the routine use of temporary porto-caval shunt (Quality of evidence: Very Low | Grade of Recommendation: Strong).

Liver Transplantation in Recipients With Class III Obesity: Posttransplant Outcomes and Weight Gain

Background.

There has been a dramatic increase in obesity in the United States. Several studies have reported conflicting results for the impact of obesity on outcomes of liver transplantation (LT). This study aims to assess the impact of obesity on LT and changes in body mass index (BMI) after transplantation.

Methods.

All adult LTs performed at Indiana University between 2001 and 2018 were reviewed. BMIs of recipients were subdivided into 6 categories. Survival outcomes were compared across the subgroup. BMI was followed up in a cohort of patients from 2008 to 2018.

Results.

Among 2024 patients, 25% were in class I obesity, 9.3% were in class II obesity, and 1.1% were in class III obesity. There was no significant difference in patient and graft survival at 10-y follow-up with respect to BMI. Among 1004 patients in the subgroup, BMI of all groups except the underweight group declined in the first 3 mo postoperatively; however, the BMI of all groups except the class III obesity group returned to the pre-LT level by 2 y and reached a plateau by 5 y. In the class III obesity group, there was a significant increase in body weight at 5 y.

Conclusions.

Class III obesity was not associated with higher mortality in our cohort. Because our cohort is small, it may be underpowered to detect a smaller difference in outcome. From our observation, obesity should not be considered a contraindication for LT. Post-LT interventions are required to prevent significant weight gain for the class III obesity group.

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.

Blood Cell Salvage and Autotransfusion Does Not Worsen Oncologic Outcomes Following Liver Transplantation with Incidental Hepatocellular Carcinoma: A Propensity Score-Matched Analysis

BACKGROUND

Intraoperative blood cell salvage and autotransfusion (IBSA) during liver transplantation (LT) for hepatocellular carcinoma (HCC) is controversial for concern regarding adversely impacting oncologic outcomes.

OBJECTIVE

We aimed to evaluate the long-term oncologic outcomes of patients who underwent LT with incidentally discovered HCC who received IBSA compared with those who did not receive IBSA.

METHODS

Patients undergoing LT (January 2001-October 2018) with incidental HCC on explant pathology were retrospectively identified. A 1:1 propensity score matching (PSM) was performed. HCC recurrence and patient survival were compared. Kaplan-Meier survival analyses were performed, and univariable Cox proportional hazard analyses were performed for risks of recurrence and death.

RESULTS

Overall, 110 patients were identified (IBSA, n = 76 [69.1%]; non-IBSA, n = 34 [30.9%]). Before matching, the groups were similar in terms of demographics, transplant, and tumor characteristics. Overall survival was similar for IBSA and non-IBSA at 1, 3, and 5 years (96.0%, 88.4%, 83.0% vs. 97.1%, 91.1%, 87.8%, respectively; p = 0.79). Similarly, the recurrence rate at 1, 3, and 5 years was not statistically different (IBSA 0%, 1.8%, 1.8% vs. non-IBSA 0%, 3.2%, 3.2%, respectively; p = 0.55). After 1:1 matching (26 IBSA, 26 non-IBSA), Cox proportional hazard analysis demonstrated similar risk of death and recurrence between the groups (IBSA hazard ratio [HR] of death 1.26, 95% confidence interval [CI] 0.52-3.05, p = 0.61; and HR of recurrence 2.64, 95% CI 0.28-25.30, p = 0.40).

CONCLUSIONS

IBSA does not appear to adversely impact oncologic outcomes in patients undergoing LT with incidental HCC. This evidence further supports the need for randomized trials evaluating the impact of IBSA use in LT for HCC.

Validation of predictive models identifying patients at risk for massive transfusion during liver transplantation and their potential impact on blood bank resource utilization

BACKGROUND

Intraoperative massive transfusion (MT) is common during liver transplantation (LT). A predictive model of MT has the potential to improve use of blood bank resources.

STUDY DESIGN AND METHODS

Development and validation cohorts were identified among deceased-donor LT recipients from 2010 to 2016. A multivariable model of MT generated from the development cohort was validated with the validation cohort and refined using both cohorts. The combined cohort also validated the previously reported McCluskey risk index (McRI). A simple modified risk index (ModRI) was then created from the combined cohort. Finally, a method to translate model predictions to a population-specific blood allocation strategy was described and demonstrated for the study population.

RESULTS

Of the 403 patients, 60 (29.6%) in the development and 51 (25.5%) in the validation cohort met the definition for MT. The ModRI, derived from variables incorporated into multivariable model, ranged from 0 to 5, where 1 point each was assigned for hemoglobin level of less than 10 g/dL, platelet count of less than 100 × 10⁹ /dL, thromboelastography R interval of more than 6 minutes, simultaneous liver and kidney transplant and retransplantation, and a ModRI of more than 2 defined recipients at risk for MT. The multivariable model, McRI, and ModRI demonstrated good discrimination (c statistic [95% CI], 0.77 [0.70-0.84]; 0.69 [0.62-0.76]; and 0.72 [0.65-0.79], respectively, after correction for optimism). For blood allocation of 6 or 15 units of red blood cells (RBCs) based on risk of MT, the ModRI would prevent unnecessary crossmatching of 300 units of RBCs/100 transplants.

CONCLUSIONS

Risk indices of MT in LT can be effective for risk stratification and reducing unnecessary blood bank resource utilization.

Postoperative Atrial Fibrillation and Flutter in Liver Transplantation: An Important Predictor of Early and Late Morbidity and Mortality

Postoperative atrial fibrillation/flutter (POAF) is the most common perioperative arrhythmia and may be particularly problematic after liver transplantation (LT). This study is a single-center retrospective analysis of POAF to determine its incidence following LT, to identify risk factors, to assess its impact on clinical outcomes, and to summarize management strategies. The records of all patients who underwent LT between 2010 and 2018 were reviewed. Extracted data included pre-LT demographics and cardiac evaluation, in-hospital post-LT cardiac events, early and late complications, and survival. Among 1011 patients, the incidence of post-LT POAF was 10%. Using binary logistic regression, pre-LT history of atrial fibrillation was the strongest predictor of POAF (odds ratio [OR], 6.72; 95% confidence interval [CI], 2.00-22.57; P < 0.001), followed by history of coronary artery disease (CAD; OR, 2.52; 95% CI, 1.10-5.81; P = 0.03). Cardiac stress testing abnormality and CAD on cardiac catheterization were also associated with higher risk. Median time to POAF onset after LT was 3 days with 72% of cases resolving within 48 hours. POAF patients had greater hospital length of stay, death during the LT admission, and 90-day and 1-year mortality. POAF was an independent risk factor for post-LT mortality (OR, 2.0; 95% CI, 1.3-3.0; P < 0.01). Amiodarone was administered to 73% of POAF patients with no evidence of increased serum alanine aminotransferase levels. POAF occurred in 10% of post-LT patients with early onset and rapid resolution in most affected patients. POAF patients, however, had significant morbidity and mortality, suggesting that POAF is an important marker for worse early and late post-LT outcomes.

Expanding the Donor Pool With the Use of Extended Criteria Donation After Circulatory Death Livers

Use of donation after circulatory death (DCD) donor livers for transplantation has remained cautious in the United States. The aim of this study was to demonstrate the expansion of a DCD liver transplantation (LT) program with the use of extended criteria donor (ECD) DCD livers. After institutional review board approval, 135 consecutive DCD LTs were retrospectively studied. ECD DCD livers were defined as those with 1 of the following factors: donor age >50 years, donor body mass index >35 kg/m² , donor functional warm ischemia time >30 minutes, and donor liver macrosteatosis >30%. An optimization protocol was introduced in July 2011 to improve outcomes of DCD LT, which included thrombolytic donor flush and efforts to minimize ischemia times. The impact of this protocol on outcomes was evaluated in terms of graft loss, ischemic cholangiopathy (IC), and change in DCD LT volume. Of 135 consecutive DCD LTs, 62 were ECD DCDs. In total, 24 ECD DCD LTs were performed before (era 1) and 38 after the institution of optimization protocol (era 2), accounting for an increase in the use of ECD DCD livers from 39% to 52%. Overall outcomes of ECD DCD LT improved in era 2, with a significantly lower incidence of IC (5% versus 17% in era 1; P = 0.03) and better 1-year graft survival (93% versus 75% in era 1; P = 0.07). Survival outcomes for ECD DCD LT in era 2 were comparable to matched deceased donor LT. With the expansion of the DCD donor pool, the number of DCD LTs performed at our center gradually increased in era 2 to account for >20% of the center's LT volume. In conclusion, with the optimization of perioperative conditions, ECD DCD livers can be successfully transplanted to expand the donor pool for LT.

Risk Factors for Transfusion after Orthotopic Liver Transplantation

Background

Transfusion of blood products during orthotopic liver transplantation (OLT) is associated with increased morbidity and mortality. Although risk factors associated with intraoperative transfusion requirements have been widely assessed, published data on the prediction of postoperative transfusion requirements are sparse.

Objectives

The aim of this study was to evaluate risk factors for postoperative allogeneic transfusion requirements in OLT.

Methods

Clinical characteristics and intraoperative parameters of 645 consecutive adult patients undergoing OLT were retrospectively reviewed. Multivariate logistic regression was used to determine the main determinants for postoperative transfusion requirements.

Results

Determinants of postoperative transfusion requirements of any blood product in the postoperative period were the number of blood products transfused in the intraoperative period (OR 1.17, 95% CI 1.08-1.28), warm ischemia time (OR 1.05, 95% CI 1.02-1.08), MELD score (OR 1.05, 95% CI 1.01-1.08) and hepatocellular carcinoma (OR 0.45, 95% CI 0.28-0.72). A dose-dependent effect between the number of units transfused in the intraoperative period and transfusion requirements in the postoperative period was also observed. The relative risk of postoperative allogeneic transfusion of any blood component was 5.9 (95% CI 3.4-10.4) for patients who received 1-2 units in the intraoperative period, 7.3 (95% CI 3.6-14.7) for those who received 3-5 units in the intraoperative period, and 11.1 (95% CI 4.7-26.4) for those who received 6 or more units, when compared to no intraoperative blood transfusion.

Conclusion

Our study demonstrated an association between intraoperative transfusion and warm ischemia time with postoperative transfusion requirements. The identification of risk factors for transfusion in the postoperative period may improve management of these patients by increasing awareness to bleeding complications in this high-risk population and by expanding hemostasis monitoring to the postoperative period.

The System of Blood Coagulation in Normal and in Liver Transplantation (Review)

The review dwells on the problem of hemostatic disorders in patients undergoing liver transplantation and their correction in the perioperative period. The physiology of the hemostatic system, disorders of the blood coagulation system in patients at various stages of liver transplantation, correction of hemostatic disorders during and after orthotopic liver transplantation are discussed. Liver transplantation is performed in patients with liver diseases in the terminal stage of liver failure. At the same time, changes in the hemostatic system of these patients pose a significant risk of developing bleeding and/or thrombosis during and after liver transplantation. The hypothesis is suggested that the personalized correction of hemostasis disorder in liver transplantation should be based on considerating the nosological forms of the liver damage, mechanisms of development of recipient’s hemostatic disorders, and the stage of the surgery.

SEALIVE: the use of technical vessel-sealing devices for recipient hepatectomy in liver transplantation: study protocol for a randomized controlled trial

Background

The surgical technique used in liver transplantation has undergone constant evolution in an effort to develop a safe, highly standardized procedure. Despite this, the initial step of recipient hepatectomy has not been the focus of clinical research thus far. Due to advanced coagulopathy in liver transplant recipients, this part of the operation still carries the risk of severe hemorrhage. This trial is designed to compare an electrothermal bipolar vessel sealing device (LigaSure™) and an ultrasound dissector (HARMONIC ACE®+7) with standard surgical techniques during the recipients’ hepatectomy in liver transplantation.

Methods/design

In a single-center, prospective, randomized, controlled, parallel, three-armed, confirmatory, open trial, LigaSure™ and HARMONIC ACE®+7 will be compared with standard surgical techniques that use titanium clips and conventional knot-tying ligations during recipient hepatectomy in liver transplantation. Intraoperative total blood loss is the primary endpoint of the trial. Secondary endpoints include blood loss during hepatectomy, the duration of both the hepatectomy and the entire surgical procedure, and blood transfusion requirements of the procedure. To generate reliable data, intraoperative blood loss will be recorded with respect to all rinse fluids during surgery, ascites, and by weighing used swabs. At 80% power and an alpha of 0.025 for both of the experimental groups, 23 subjects will be analyzed per protocol in each study arm in order to detect clinically relevant reduction of intraoperative blood loss. The intention-to-treat analysis will include 69 patients. The follow-up period for each patient will be 90 days for safety reasons, whereas all clinical outcomes will be measured within the first 10 postoperative days.

Discussion

To our knowledge, this is the first prospective, randomized trial comparing two innovative technical methods of vessel sealing and dissection with standard techniques for recipient hepatectomy. This will be done to detect relevant reduction of intraoperative blood loss during liver transplant. The results of the trial are expected to improve patient outcome and safety after liver transplant and to increase the general safety of this procedure.

Trial registration

ClinicalTrials.gov, NCT 03323242. Registered on October 26, 2017.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2778-1) contains supplementary material, which is available to authorized users.

Established and potential predictors of blood loss during lung transplant surgery

Lung transplantation is an established therapeutic procedure for end stage lung diseases. Its success may be impaired by perioperative complications. Intraoperative blood loss and the resulting blood transfusion are among the most common complications. The various factors contributing to increased blood loss during lung transplantation are only scarcely investigated and not yet completely understood. This is in sharp contrast to other surgical fields, as in orthopedic surgery, liver transplantation and cardiac surgery the contributors to blood loss are well identified. This narrative review article aims to highlight the acknowledged factors influencing blood loss in lung transplantation (such as double vs. single lung transplant) and to discuss potential factors that may be of interest for further research or helpful to develop strategies targeting risk factors in order to minimize blood loss during lung transplantation and finally improve patient outcome.

A data-driven patient blood management strategy in liver transplantation

BACKGROUND AND OBJECTIVES

Blood utilization during liver transplant has decreased, but remains highly variable due to many complex surgical and physiologic factors. Previous models attempted to predict utilization using preoperative variables to stratify cases into two usage groups, usually using entire blood units for measurement. We sought to develop a practical predictive model using specific transfusion volumes (in ml) to develop a data-driven patient blood management strategy.

MATERIALS AND METHODS

This is a retrospective evaluation of primary liver transplants at a single institution from 2013 to 2015. Multivariable analysis of preoperative recipient and donor factors was used to develop a model predictive of intraoperative red-blood-cell (pRBC) use.

RESULTS

Of 256 adult liver transplants, 207 patients had complete transfusion volume data for analysis. The median intraoperative allogeneic pRBC transfusion volume was 1250 ml, and the average was 1563 ± 1543 ml. Preoperative haemoglobin, spontaneous bacterial peritonitis, preoperative haemodialysis and preoperative international normalized ratio together yielded the strongest model predicting pRBC usage. When it predicted <1250 ml of pRBCs, all cases with 0 ml transfused were captured and only 8·6% of the time >1250 ml were used. This prediction had a sensitivity of 0·91 and a specificity of 0·89. If predicted usage was >2000 ml, 75% of the time blood loss exceeded 2000 ml.

CONCLUSION

Patients likely to require low or high pRBC transfusion volumes were identified with excellent accuracy using this predictive model at our institution. This model may help predict bleeding risk for each patient and facilitate optimized blood ordering.

Compared efficacy of preservation solutions on the outcome of liver transplantation: Meta-analysis

AIM

To compare the effects of the four most commonly used preservation solutions on the outcome of liver transplantations.

METHODS

A systematic literature search was performed using MEDLINE, Scopus, EMBASE and the Cochrane Library databases up to January 31st, 2017. The inclusion criteria were comparative, randomized controlled trials (RCTs) for deceased donor liver (DDL) allografts with adult and pediatric donors using the gold standard University of Wisconsin (UW) solution or histidine-tryptophan-ketoglutarate (HTK), Celsior (CS) and Institut Georges Lopez (IGL-1) solutions. Fifteen RCTs (1830 livers) were included; the primary outcomes were primary non-function (PNF) and one-year post-transplant graft survival (OGS-1).

RESULTS

All trials were homogenous with respect to donor and recipient characteristics. There was no statistical difference in the incidence of PNF with the use of UW, HTK, CS and IGL-1 (RR = 0.02, 95%CI: 0.01-0.03, P = 0.356). Comparing OGS-1 also failed to reveal any difference between UW, HTK, CS and IGL-1 (RR = 0.80, 95%CI: 0.80-0.80, P = 0.369). Two trials demonstrated higher PNF levels for UW in comparison with the HTK group, and individual studies described higher rates of biliary complications where HTK and CS were used compared to the UW and IGL-1 solutions. However, the meta-analysis of the data did not prove a statistically significant difference: the UW, CS, HTK and IGL-1 solutions were associated with nearly equivalent outcomes.

CONCLUSION

Alternative solutions for UW yield the same degree of safety and effectiveness for the preservation of DDLs, but further well-designed clinical trials are warranted.

Preoperative treatment with 5α-reductase inhibitors and the risk of hemorrhagic events in patients undergoing transurethral resection of the prostate - A population-based cohort study

OBJECTIVES

To assess the associations between preoperative treatment with 5-alpha reductase inhibitors and the risks of blood transfusion during transurethral resection of the prostate and blood clot evacuation or emergency department visits for hematuria within 1 month after surgery.

METHODS

We used data from the Taiwan National Health Insurance Research Database in this population-based cohort study. A total of 3,126 patients who underwent first-time transurethral resection of the prostate from 2004 to 2013 were identified. Adjusted odds ratios estimated by multiple logistic regression models were used to assess the independent effects of the preoperative use of 5-alpha reductase inhibitors on the risks of perioperative hemorrhagic events after adjustment for potential confounders.

RESULTS

Two hundred and ninety-seven (9.4%) patients were treated with 5-alpha reductase inhibitors for <3 months, and 65 (2.1%) patients were treated for ≥3 months prior to undergoing transurethral resection of the prostate. The blood transfusion rates for patients who were not treated with 5-alpha reductase inhibitors (controls), patients who were treated with 5-alpha reductase inhibitors for <3 months, and patients who were treated with 5-alpha reductase inhibitors ≥3 months were 9.5%, 8.8%, and 3.1%, respectively. 5-alpha reductase inhibitors tended to decrease the risk of blood transfusion; however, this association was not statistically significant (adjusted odds ratio=0.14, 95% confidence interval: 0.02-1.01). Age ≥80 years, coagulopathy, and a resected prostate tissue weight >50 g were associated with significantly higher risks of blood transfusion than other parameters.

CONCLUSIONS

This nationwide study did not show that significant associations exist between 5-alpha reductase inhibitor use before transurethral resection of the prostate and the risks of blood transfusion and blood clot evacuation or emergency visits for hematuria.

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.

Thrombin activatable fibrinolysis inhibitor as a bleeding predictor in liver transplantation: a pilot observational study

OBJECTIVE

To correlate the levels of thrombin activatable fibrinolysis inhibitor in the immediate postoperative period and at 24 hours postoperatively with the volume of intraoperative bleeding.

METHODS

Twenty-one patients allocated immediately before (elective or emergency) liver transplantation were analyzed. Blood samples were collected for thrombin activatable fibrinolysis inhibitor analysis at three different time points: immediately before liver transplantation (preoperative thrombin activatable fibrinolysis inhibitor), immediately after the surgical procedure (immediate postoperative thrombin activatable fibrinolysis inhibitor), and 24 hours after surgery (thrombin activatable fibrinolysis inhibitor 24 hours after surgery). The primary outcome of the study was to correlate the preoperative and immediate postoperative levels of thrombin activatable fibrinolysis inhibitor with intraoperative blood loss.

RESULTS

There was a correlation between the preoperative thrombin activatable fibrinolysis inhibitor levels and bleeding volume (ρ = -0.469; p = 0.05) but no correlation between the immediate postoperative thrombin activatable fibrinolysis inhibitor and bleeding volume (ρ = -0.062; p = 0.79). No variable included in the linear regression analysis (prehemoglobin, prefibrinogen and preoperative thrombin activatable fibrinolysis inhibitor) was a bleeding predictor. There was a similar trend in the variation between the levels of thrombin activatable fibrinolysis inhibitor at the three different time points and fibrinogen levels. Patients who died within 6 months (14.3%) showed decreased preoperative and immediate postoperative levels of thrombin activatable fibrinolysis compared with survivors (preoperative: 1.3 ± 0.15 versus 2.55 ± 0.53, p = 0.06; immediate postoperative: 1.2 ± 0.15 versus 2.5 ± 0.42, p = 0.007).

CONCLUSION

There was a moderate correlation between preoperative thrombin activatable fibrinolysis inhibitor and intraoperative bleeding in liver transplantation patients, although the predictive role of this variable independent of other variables remains uncertain. Preoperative and immediate postoperative thrombin activatable fibrinolysis inhibitor levels may have a role in the survival prognosis of this population; however, this possibility requires confirmation in further studies with larger sample sizes.

Prognostic impact of postoperative low platelet count after liver transplantation

BACKGROUND

The positive impact of platelets has been recently implicated in liver transplantation (LT). The aim of this study was to determine the risk factors for graft loss and mortality after LT, focusing on perioperative platelet counts.

METHODS

We reviewed all deceased donor LT from 2000 to 2012 and enrolled 975 consecutive recipients. The risk factors for graft loss and mortality were analyzed by multivariate analysis, using Cox's regression model.

RESULTS

Using cutoff values acquired by receiver operating characteristics curve analysis, multivariate analyses determined that viral hepatitis C (hazard ratio [HR]=1.32), donor age >40 (HR=1.33), higher peak serum alanine aminotransferase (HR=1.01), reoperation within 30 days (HR=1.51), and platelet count <72 500/μL on postoperative day (POD) 5 (HR=1.30) were independent risk factors for graft loss. Viral hepatitis C (HR=1.33), reoperation within 30 days (HR=1.35), and platelet count <72 500/μL on POD 5 (HR=1.38) were independent risk factors for mortality.

CONCLUSION

A low platelet count on POD 5 was associated with graft loss and mortality after LT. Platelet count <72 500/μL on POD 5 can be a predictor of poor graft and overall survival. Maintaining higher postoperative platelet counts could potentially improve graft and overall survival rates.

Vena cava encirclement predicts difficult native hepatectomy

Recipient hepatectomy is a challenging liver transplantation (LT) procedure that has life-threatening complications. The current predictive mortality clinic-biological scores (Child/Model for End-Stage Liver Disease [MELD]) do not take into consideration the recipient's liver anatomy. The aim of this study was to evaluate the impact of the dorsal sector anatomy of a cirrhotic liver on the morbidity/mortality rates of hepatectomy. A multicenter retrospective study (clinic-biological and morphologic) was performed from 2013 to 2014. The degree of encirclement of the inferior vena cava (IVC) by the dorsal sector of the liver was measured. The study population included 320 patients. Seventy-four (23%) patients had complete IVC encirclement. A correlation (P = 0.01) has been reported between the existence of a circular dorsal sector and the number of transfusions during LT (4 packed red blood cell [PRBC] transfusions in the group without IVC versus 7 PRBC transfusions in the other group). The existence of such anatomy increases the relative risk of early reoperation for IVC bleeding by 31% (P = 0.05). There is a correlation between alcoholic cirrhosis and dorsal-sector hypertrophy (126 cc versus 147.5 cc; P = 0.05). Concerning surgical time, we found no significant between-group differences. Compared to the severity of cirrhosis, an inverse correlation was observed between the MELD and Child scores and the dorsal sector hypertrophy (P < 0.001). No significant difference in terms of transfusion was found between the temporary portocaval shunt group (n = 168) and the other group (n = 152). The presence of a circular sector is associated with an increased risk of hemorrhage during hepatectomy, as well as an immediate postoperative risk of reoperation. Liver Transplantation 22 906-913 2016 AASLD.

Massive haemorrhage in liver transplantation: Consequences, prediction and management

From its inception the success of liver transplantation has been associated with massive blood loss. Massive transfusion is classically defined as > 10 units of red blood cells within 24 h, but describing transfusion rates over a shorter period of time may reduce the potential for survival bias. Both massive haemorrhage and transfusion are associated with increased risk of mortality and morbidity (need for dialysis/surgical site infection) following liver transplantation although causality is difficult to prove due to the observational design of most trials. The blood loss associated with liver transplantation is multifactorial. Portal hypertension secondary to cirrhosis results in extensive collateral circulation, which can bleed during hepatectomy particular if portal pressures are increased. Avoiding volume loading and maintenance of a low central venous pressure together with the use of vasopressors have been shown to reduce blood loss and transfusion during liver transplantation, but may increase the risk of renal impairment post-operatively. Coagulation defects may be present pre-transplant, but haemostasis is often re-balanced due to a deficit in both pro- and anti-coagulation factors. Further derangement of haemostasis may develop in the anhepatic and neohepatic phases due to absent hepatic metabolic function, hyperfibrinolysis and platelet sequestration in the donor liver. Point-of-care tests of coagulation such as the viscoelastic tests rotation thromboelastometry/thromboelastometry allow and more accurate and rapid assessment of these derangements in coagulation and guide the use of factor replacement and antifibrinolytics. Transfusion protocols guided by these tests have been shown to reduce transfusion rates compared with conventional coagulation tests, but have not shown improvements in mortality or morbidity. Pre-operative factors associated with massive transfusion include previous surgery, re-do transplantation, the aetiology and severity of liver disease. Intra-operatively the use of piggy-back technique and avoiding veno-veno bypass has been shown to reduced blood loss.

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.

Reduced Transfusion During OLT by POC Coagulation Management and TEG Functional Fibrinogen: A Retrospective Observational Study

Patients undergoing orthotopic liver transplantation are at high risk of bleeding complications. Several Authors have shown that thromboelastography (TEG)-based coagulation management and the administration of fibrinogen concentrate reduce the need for blood transfusion.

METHODS

We conducted a single-center, retrospective cohort observational study (Modena Polyclinic, Italy) on 386 consecutive patients undergoing liver transplantation. We assessed the impact on resource consumption and patient survival after the introduction of a new TEG-based transfusion algorithm, requiring also the introduction of the fibrinogen functional thromboelastography test and a maximum amplitude of functional fibrinogen thromboelastography transfusion cutoff (7 mm) to direct in administering fibrinogen (2012-2014, n = 118) compared with a purely TEG-based algorithm previously used (2005-2011, n = 268).

RESULTS

After 2012, there was a significant decrease in the use of homologous blood (1502 ± 1376 vs 794 ± 717 mL, P < 0.001), fresh frozen plasma (537 ± 798 vs 98 ± 375 mL, P < 0.001), and platelets (158 ± 280 vs 75 ± 148 mL, P < 0.005), whereas the use of fibrinogen increased (0.1 ± 0.5 vs 1.4 ± 1.8 g, P < 0.001). There were no significant differences in 30-day and 6-month survival between the 2 groups.

CONCLUSIONS

The implementation of a new coagulation management method featuring the addition of the fibrinogen functional thromboelastography test to the TEG test according to an algorithm which provides for the administration of fibrinogen has helped in reducing the need for transfusion in patients undergoing liver transplantation with no impact on their survival.

Severe Acute Anemia After Liver Transplantation in an Elderly Jehovah's Witness Treated With High-dose Erythropoietin and Ferric Carboxymaltose: A Case Report

BACKGROUND

There is no standard treatment for patients with severe anemia who refuse blood transfusion or cannot receive red blood cells.

CASE REPORT

After an orthotopic liver transplantation, an elderly Jehovah's Witness who refused blood transfusion presented with severe acute anemia with hemorrhagic shock. The calculated red blood cell loss was near 70%. Associated with surgical treatment and supportive measures, the patient was treated with high-dose erythropoietin and ferric carboxymaltose.

RESULTS

The patient presented a rapid increase in hemoglobin concentration and reticulocyte count with resolution of hemorrhagic shock after the proposed pharmacologic treatment combined with local hemostatic measures. She was transferred to a low-risk unit 4 days after transplantation and was discharged from the hospital on day 10. The hemoglobin concentration was normal 35 days after the bleeding event.

CONCLUSION

This case demonstrated that a protocol with high-dose erythropoietin and ferric carboxymaltose may be an option for patients with severe anemia who refuse blood transfusion or cannot receive red blood cells.

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.

Transfusion management and immunohematologic complications in liver transplantation: experience of a single institution

OBJECTIVE

Liver transplantation (LT) has traditionally been associated with major blood loss and consequently high blood transfusion requirements. Our objective was to analyze transfusion management and incidence of immunohematologic complications in patients undergoing LT at our institution.

METHODS

A retrospective analysis of immunohematologic events and transfusion outcomes was carried out at La Fe University Hospital in Valencia. Data from 654 patients were reviewed: 654 underwent only one LT while 36 underwent second LT.

RESULTS

Patients received a median of 3 red blood cell (RBC) concentrates, 2 platelets concentrates (PCs) and 2 fresh frozen plasma units (FFPs). Variables significantly influencing RBC transfusions were: the MELD score, hemoglobin levels, and the platelet counts before LT. 27 patients (4.1%) had a positive antibody screening before transplant. Immunohematologic events occurred in 8% of the patients, mostly in the first month after LT, and involved hemolysis in 13 cases. Mortality was significantly higher in patients developing immunohematologic disorders (42.8 vs. 18.3%; p < 0.001). In the multivariable analysis, only ABO minor incompatibility between donor and recipient significantly increased the appearance of immunohematologic incidences (OR 4.92, 95% CI 2.31-10.50; p < 0.001).

CONCLUSION

Transfusion management of patients that underwent LT can be complicated by immunohematologic problems. Blood banks should implement the DAT test in each transfusion to detect them.

Transfusion and coagulation management in liver transplantation

There is wide variation in the management of coagulation and blood transfusion practice in liver transplantation. The use of blood products intraoperatively is declining and transfusion free transplantations take place ever more frequently. Allogenic blood products have been shown to increase morbidity and mortality. Primary haemostasis, coagulation and fibrinolysis are altered by liver disease. This, combined with intraoperative disturbances of coagulation, increases the risk of bleeding. Meanwhile, the rebalancing of coagulation homeostasis can put patients at risk of hypercoagulability and thrombosis. The application of the principles of patient blood management to transplantation can reduce the risk of transfusion. This includes: preoperative recognition and treatment of anaemia, reduction of perioperative blood loss and the use of restrictive haemoglobin based transfusion triggers. The use of point of care coagulation monitoring using whole blood viscoelastic testing provides a picture of the complete coagulation process by which to guide and direct coagulation management. Pharmacological methods to reduce blood loss include the use of anti-fibrinolytic drugs to reduce fibrinolysis, and rarely, the use of recombinant factor VIIa. Factor concentrates are increasingly used; fibrinogen concentrates to improve clot strength and stability, and prothrombin complex concentrates to improve thrombin generation. Non-pharmacological methods to reduce blood loss include surgical utilisation of the piggyback technique and maintenance of a low central venous pressure. The use of intraoperative cell salvage and normovolaemic haemodilution reduces allogenic blood transfusion. Further research into methods of decreasing blood loss and alternatives to blood transfusion remains necessary to continue to improve outcomes after transplantation.

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.

Coagulopathy management in liver transplantation

Risk of bleeding and transfusion in liver transplantation is determined by age, severity of liver disease, as well as hemoglobin and plasma fibrinogen values. During the hepatectomy and the anhepatic phase, the coagulopathy is related to a decrease in clotting factors caused by surgical bleeding, facilitated by the increased portal hypertension and esophageal-gastric venous distension. Corrections of hematologic disturbances by administration of large volumes of crystalloid, colloid, or blood products may worsen the coagulopathy. Also, impaired clearance of fibrinolytic enzymes released from damaged cells can lead to primary fibrinolysis. At time of graft reperfusion further deterioration may occur as characterized by global reduction among all coagulation factors, decreased plasminogen activator inhibitor factors, and simultaneous generation of tissue plasminogen activator. In situations with inherent risk of bleeding, hypofibrinogenemia must be corrected. Concern about unwanted events is a major limitation of preventive therapy. There is some evidence for the efficacy of antifibrinolytic drugs to reduce red blood cell requirements. A guide for antifibrinolytic therapy are clot firmness in trhomboelastometry or alternatively, diffuse bleeding associated to a fibrinogen value less than 1 g/L. Because thrombin generation is limited in severe thrombocytopenia, platelet administration is recommended when active bleeding coexists with a platelet count below 50,000/mm(3). When the administration of hemoderivates and antifibrinolytic drugs does not correct severe bleeding, consumption coagulopathy and secondary fibrinolysis should be suspected. Treatment of affected patients should be based upon correcting the underlying cause, mostly related to tissue hypoxia due to critical hypoperfusion.

Changes in transfusion practice over time in adult patients undergoing liver transplantation

OBJECTIVE

The aim of this study was to investigate changes in transfusion practice over time in liver transplantation surgery and to evaluate potential causes for changes in practice and report associated perioperative morbidity and mortality.

DESIGN

A retrospective cohort study.

SETTING

A single tertiary referral academic hospital.

PARTICIPANTS

Two cohorts of 100 sequential adult primary liver transplant recipients: Early practice (1990-1991) and recent practice (2005-2006).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Perioperative transfusion and hemoglobin data were recorded. Mortality and postoperative complications were identified up to 30 days postoperatively. Appropriate intergroup statistical comparisons were made; p ≤ 0.05 was considered statistically significant. Compared with the early group, the recent group had significantly fewer perioperative allogeneic red blood cell transfusions, intraoperative autotransfusions, and transfusions of other blood products. No change in perioperative transfusion triggers was identified. There were no significant alterations in perioperative morbidity or mortality.

CONCLUSIONS

When compared with patients in the early group, recent cohort patients received significantly fewer blood transfusions. The authors attribute this observation to changes in surgical technique rather than a significant alteration in transfusion triggers over the studied time period.

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.

Risk factors and outcomes of massive red blood cell transfusion following living donor liver transplantation

OBJECTIVES

To identify the factors influencing blood loss and secondary blood transfusion and to investigate the outcomes of patients who underwent a massive blood transfusion (MBT) following living donor liver transplantation (LDLT).

METHODS

Patients who underwent primary adult-to-adult right hepatic lobe LDLT were included in the study, and were divided into the MBT group [≥6 red blood cell (RBC) units in 24 h] and the non-massive blood transfusion (NMBT) group (<6 RBC units in 24 h). All potential risk factors, length of intensive care unit (ICU) stay and long-term survival rate of the patients in the two groups were analyzed.

RESULTS

The data of 181 eligible patients were retrospectively analyzed. A decreased long-term survival rate, a higher incidence of postoperative infection and prolonged ICU stay were observed in the MBT group. No significant difference was observed in survival rate between patients having platelet transfusion>2 units and ≤2 units. Hemoglobin<100 g/L, platelet counts<70×10(9)/L, fibrinogen level<1.5 g/L and history of upper abdominal surgery were found to be independent risk factors.

CONCLUSIONS

Blood transfusion during LDLT can be predicted using preoperative variables. Massive RBC transfusion may lead to poor long-term survival, higher postoperative infection rate and prolonged ICU stay. Platelet transfusion may not be a risk factor for long-term survival.

[Anesthesia in the patient with impaired liver function]

We review information on impaired liver function, focusing on concepts relevant to anesthesia and postoperative recovery. The effects of impaired function are analyzed by systems of the body, with attention to the complications the patient with liver cirrhosis may develop according to type of surgery. Approaches to correcting coagulation disorders in the cirrhotic patient are particularly controversial because an increase in volume may be a factor in bleeding owing to increased portal venous pressure and imbalances in the factors that favor or inhibit coagulation. Perioperative morbidity and mortality correlate closely to Child-Pugh class and the score derived from the model for end-stage liver disease (MELD). Patients in Child class A are at moderate risk and surgery is therefore not contraindicated. Patients in Child class C or with a MELD score over 20, on the other hand, are at high risk and should not undergo elective surgical procedures. Abdominal surgery is generally considered to put patients with impaired liver function at high risk because it causes changes in hepatic blood flow and increases intraoperative bleeding because of high portal venous pressures.

Preoperative factors as predictors of blood product transfusion requirements in orthotopic liver transplantation

CONTEXT

Intraoperative transfusion can affect the chance of graft survival in liver transplantation, a complicated operation with massive blood loss. Verification of factors that are predictive of intraoperative blood loss and transfusion increases the quality of anesthesia management.

OBJECTIVE

To assess use of blood and blood products between 2002 and 2008 and to evaluate factors associated with blood loss and requirement for blood products in adult patients undergoing orthotopic liver transplantation via piggyback technique.

DESIGN

Medical charts and anesthesia records from 261 eligible adult recipients of an orthotopic liver transplant between March 2002 and May 2008 were reviewed.

SETTING

Shiraz Liver Transplantation Center, the only active liver transplantation center in Iran.

MAIN OUTCOME MEASURES

Potential influencing factors in blood loss and transfusion, including sex, preoperative hemoglobin level, international normalized ratio, primary diagnosis, platelet count, creatinine level, Model for End-Stage Liver Disease (MELD) score, central venous pressure, and total anesthesia time, were measured and subjected to multivariable analysis.

RESULTS

Mean blood loss was 54.2 (SD, 47.9) mL/kg, the mean (SD) for amounts of blood products transfused was 25.3 (19.5) mL/kg for packed red blood cells, 2.6 (3.3) units for fresh frozen plasma, and 1.7 (3.1) units for platelets. Seven recipients (2.7%) underwent transplantation without intraoperative transfusion of red blood cells, whereas 25 patients (9.6%) received more than 10 units of red blood cells intraoperatively. Multivariable analysis showed that no preoperative factor was a predictor of blood loss or requirement for intraoperative transfusion. Transfusion of fresh frozen plasma and packed red blood cells was significantly lower in 2005, 2006, 2007, and 2008 than in 2003 to 2004 (P < .001).