Derivation of a risk index for the prediction of massive blood transfusion in liver transplantation

Hemostatic balance in patients with liver cirrhosis: Report of a consensus conference

Patients with cirrhosis present with hemostatic alterations secondary to reduced availability of pro-coagulant and anti-coagulant factors. The net effect of these changes is a rebalanced hemostatic system. The Italian Association of the Study of the Liver (AISF) and the Italian Society of Internal Medicine (SIMI) promoted a consensus conference on the hemostatic balance in patients with cirrhosis. The consensus process started with the review of the literature by a scientific board of experts and ended with a formal consensus meeting in Rome in December 2014. The statements were graded according to quality of evidence and strength of recommendations, and approved by an independent jury. The statements presented here highlight strengths and weaknesses of current laboratory tests to assess bleeding and thrombotic risk in cirrhotic patients, the pathophysiology of hemostatic perturbations in this condition, and outline the optimal management of bleeding and thrombosis in patients with liver cirrhosis.

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.

Development and validation of a predictive score for perioperative transfusion in patients with hepatocellular carcinoma undergoing liver resection

BACKGROUND

Liver resection is a major surgery requiring perioperative blood transfusion. Predicting the need for blood transfusion for patients undergoing liver resection is of great importance. The present study aimed to develop and validate a model for predicting transfusion requirement in HBV-related hepatocellular carcinoma patients undergoing liver resection.

METHODS

A total of 1543 consecutive liver resections were included in the study. Randomly selected sample set of 1080 cases (70% of the study cohort) were used to develop a predictive score for transfusion requirement and the remaining 30% (n=463) was used to validate the score. Based on the preoperative and predictable intraoperative parameters, logistic regression was used to identify risk factors and to create an integer score for the prediction of transfusion requirement.

RESULTS

Extrahepatic procedure, major liver resection, hemoglobin level and platelets count were identified as independent predictors for transfusion requirement by logistic regression analysis. A score system integrating these 4 factors was stratified into three groups which could predict the risk of transfusion, with a rate of 11.4%, 24.7% and 57.4% for low, moderate and high risk, respectively. The prediction model appeared accurate with good discriminatory abilities, generating an area under the receiver operating characteristic curve of 0.736 in the development set and 0.709 in the validation set.

CONCLUSIONS

We have developed and validated an integer-based risk score to predict perioperative transfusion for patients undergoing liver resection in a high-volume surgical center. This score allows identifying patients at a high risk and may alter transfusion practices.

Preoperative hypoalbuminemia and anemia as predictors of transfusion in radical nephrectomy for renal cell carcinoma: a retrospective study

Background

The only curative therapy for renal cell carcinoma is the complete removal of malignant tissue. Surgical bleeding during radical nephrectomy may require blood transfusion. Blood transfusion, however, is associated with postoperative morbidity and mortality. This study investigated predictive factors of transfusion requirement in patients undergoing radical nephrectomy, as well as the effects of transfusion on postoperative outcomes.

Methods

This study retrospectively enrolled 526 patients who underwent open radical nephrectomy for renal cell carcinoma between 2010 and 2012. Univariate and multivariate logistic regression analyses were used to determine independent predictive factors of a requirement for packed red blood cell (PRBC) transfusion. Postoperative outcomes included an admission to the intensive care unit (ICU) and lengths of ICU and hospital stay.

Results

Of the 526 patients, 93 (17.7 %) required PRBC transfusion, with these patients requiring a mean 5.5 units. Preoperative hypoalbuminemia (serum albumin <3.5 g/dL) was observed in 75 (14.3 %) patients, and preoperative anemia (hemoglobin <12.0 g/dL) in 121 (23.0 %). Multivariate logistic regression analysis showed that preoperative hypoalbuminemia, preoperative anemia, and a high cancer stage were independent factors significantly associated with PRBC transfusion in open radical nephrectomy. The transfused group had higher incidence of ICU admission and longer lengths of ICU and hospital stay than the non-transfused group.

Conclusions

Preoperative hypoalbuminemia and anemia are important predictors of PRBC transfusion during radical nephrectomy for renal cell carcinoma. Furthermore, transfusion is associated with poor postoperative outcomes.

Reliability of a point-of-care device for international normalized ratio testing during the three surgical phases of orthotopic liver transplantation: a retrospective observational study

PURPOSE

To investigate the reliability of a point-of-care device, the HEMOCHRON(®) Jr. Signature, for measuring the international normalized ratio (INR) during the three surgical phases of liver transplantation.

METHODS

A retrospective review was performed on patients undergoing liver transplantation during July to December 2013. Thirty-one patients who had simultaneous laboratory and point-of-care INR readings from each phase of liver transplant surgery (paleohepatic, anhepatic, and neohepatic) were eligible for inclusion. Bland-Altman analysis, Spearman's rank correlation, and four quadrant plots were used to compare INR results from the point-of-care device (pocINR) with those from the laboratory (labINR).

RESULTS

Based on the Bland-Altman analysis, mean biases (95% prediction interval) were 0.10 (0.03 to 0.17), 0.19 (0.12 to 0.27), and 0.21 (0.01 to 0.43) for the paleohepatic, anhepatic, and neohepatic phases, respectively. The pocINR device showed a systematic underestimation of the labINR. The Spearman's rank correlation coefficients (95% confidence interval [CI]) were: Ρ = 0.90 (95% CI 0.80 to 0.95); Ρ = 0.92 (95% CI 0.71 to 0.93); and Ρ = 0.71 (95% CI 0.46 to 0.85), respectively. Direction-of-change analysis between the paleohepatic to anhepatic and the anhepatic to neohepatic phases showed strong concordance of 84% and, also considering the small bias between the measurements, supports the use of the pocINR device in the clinical management of liver transplant surgery.

CONCLUSION

Point-of-care INR was accurate prior to hepatic reperfusion, but reliability decreased in the neohepatic phase.

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.

Review of anesthesia in liver transplantation

Liver transplantation (LT) is a well-accepted treatment modality of many end-stage liver diseases. The main issue in LT is the shortage of deceased donors to accommodate the needs of patients waiting for such transplants. Live donors have tremendously increased the pool of available liver grafts, especially in countries where deceased donors are not common. The main ethical concern of this procedure is the safety of healthy donors, who undergo a major abdominal surgery not for their own health, but to help cure others. The first part of the review concentrates on live donor selection, preanesthetic evaluation, and intraoperative anesthetic care for living liver donors. The second part reviews patient evaluation, intraoperative anesthesia monitoring, and fluid management of the recipient. This review provides up-to-date information to help improve the quality of anesthesia, and contribute to the success of LT and increase the long-term survival of the recipients.

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.

Prediction of intraoperative transfusion requirements during orthotopic liver transplantation and the influence on postoperative patient survival

BACKGROUND

Predicting blood product transfusion requirements during orthotopic liver transplantation (OLT) remains difficult. Our primary aim in this study was to determine which patient variables best predict recipient risk for large blood transfusion requirements during OLT. The secondary aim was to determine whether the amount of blood products transfused during OLT impacted patient survival.

METHODS

Eight hundred four primary adult OLTs performed during a 9-year period were retrospectively analyzed, and predictive models were developed for blood product usage, usage >20 and usage >30 units of red blood cells (RBCs) plus cell salvage (CS). For survival analysis, potential predictors included all blood products administered during OLT.

RESULTS

For analyses of RBC + CS usage, we used several statistical techniques: regression analysis, logistic regression, and classification and regression tree analysis. Several preoperative factors were highly statistically significant predictors of intraoperative blood product usage in each of the analyses, namely lower platelet count and higher Model for End-Stage Liver Disease Score or one or more of its components (creatinine, total bilirubin, international normalized ratio). Despite these highly significant associations, the models were unable to predict reliably that patients might require the largest amount of blood products during OLT. For example, the classification and regression tree analyses were able to predict only 32% and 11% of patients requiring >20 and >30 units of RBC + CS, respectively. Survival analysis demonstrated poorer survival among patients receiving larger amounts of RBC + CS during OLT.

CONCLUSION

Prediction of intraoperative blood product requirements based on preoperatively available variables is unreliable; however, there is a strong measurable association between transfusion and postoperative mortality.

Five-minute parameter of thromboelastometry is sufficient to detect thrombocytopenia and hypofibrinogenaemia in patients undergoing liver transplantation

BACKGROUND

Early detection of coagulopathy is important to prevent bleeding during liver transplantation (LT). Rotation thromboelastometry (ROTEM(®)) provides the earliest parameter of clot amplitudes at 5 min (A5). We evaluated whether A5 correlates with platelet count (PLT) and fibrinogen concentration (Fib) and can predict thrombocytopenia and hypofibrinogenaemia in hypocoagulable patients undergoing living-donor LT (LDLT).

METHODS

A total of 3446 retrospective ROTEM(®) measurements, including 1139 EXTEM, 1182 INTEM, and 1125 FIBTEM, with simultaneously measured PLT and Fib, were analysed during LDLT in 239 patients. The correlations between A5 and maximum clot firmness (MCF) index, PLT, and Fib were calculated. Receiver operating characteristic analysis with area under the curve (AUC) was used to assess A5 thresholds predictive of PLT and Fib.

RESULTS

The median PLT was 47 000 mm(-3) and the median Fib was 100 mg dl(-1) during LDLT. The A5 parameters of EXTEM (A5EXTEM) and INTEM (A5INTEM) were highly correlated with MCF (r=0.96 and r=0.95, respectively), PLT (r=0.76 and r=0.77, respectively), and Fib (r=0.63 and r=0.64, respectively). A5 of FIBTEM (A5FIBTEM) was also correlated with MCF (r=0.91) and Fib (r=0.75). A5EXTEM thresholds of 15 and 19 mm predicted PLT<30 000 mm(-3) (AUC=0.90) and <50 000 mm(-3) (AUC=0.87), respectively, whereas A5FIBTEM 4 mm predicted Fib<100 mg dl(-1) (AUC=0.86). Biases from A5EXTEM and A5FIBTEM to their MCFs were 16.4 and 1.3 mm, respectively.

CONCLUSIONS

A5 as an early variable of clot firmness is effective in detecting critically low PLT and Fib. A5 can therefore be a reliable fast index guiding transfusion therapy in hypocoagulable patients undergoing LDLT.

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.

Respiratory risk score for the prediction of 3-month mortality and prolonged ventilation after liver transplantation

Survival of critically ill patients is significantly affected by prolonged ventilation. The goal of this study was the development of a respiratory risk score (RRS) for the prediction of 3-month mortality and prolonged ventilation after liver transplantation (LT). Two hundred fifty-four consecutive LT patients from a single center were retrospectively randomized into a training group for model design and a validation group. A receiver operating characteristic (ROC) curve analysis was used to test sensitivity and specificity. The accuracy of the predictions was assessed with the Brier score, and the model calibration was assessed with the Hosmer-Lemeshow test. Cutoff values were determined with the best Youden index. The RRS was calculated in the first 24 hours as follows: (laboratory Model for End-Stage Liver Disease score > 30 = 2.36 points) + (fresh frozen plasma > 13.5 U = 2.70 points) + (partial pressure of arterial oxygen/fraction of inspired oxygen ratio < 200 mm Hg = 2.23 points) + (packed red blood cells > 10.5 U = 3.50 points) + (preoperative mechanical ventilation = 3.87 points) +  (preoperative dialysis = 2.83 points) + (donor steatosis hepatis > 40% = 2.95 points). The RSS demonstrated high predictive accuracy, good model calibration, and c statistics > 0.7 in the training and validation groups. The RSS was able to predict 3-month mortality [cutoff = 6.64, area under the (ROC) curve (AUROC) = 0.794] and prolonged ventilation (cutoff = 3.69, AUROC = 0.798) with sensitivities of 69% and 81%, specificities of 83% and 73%, and overall model correctness of 76% and 77%, respectively. In conclusion, this study provides the first prognostic model for the prediction of 3-month mortality and prolonged ventilation after LT with high sensitivity and specificity and good model accuracy. The application of the RRS to an external cohort would be desirable for its further validation and introduction as a clinical tool for intensive care resource planning and prognostic decision making.

Effects of blood products on nosocomial infections in liver transplant recipients

OBJECTIVES

Infection is the most severe complication after an organ transplant. Blood cell transfusion is an independent risk factor for adverse events, including infection in the recipient. This study sought to evaluate the effect of blood product transfusions on nosocomial infections in liver transplant patients.

MATERIALS AND METHODS

Patients who underwent a liver transplant at our hospital between 2003 and 2010 were recruited for this study. Exclusion criteria were incomplete records, patients who were hospitalized for more than 48 hours during the 4 weeks before transplant, and pediatric transplants. Incidence of nosocomial infections, which were defined as infections occurring within 30 days after transplant was the primary endpoint.

RESULTS

The incidence of nosocomial infections was 28.7%. The number of transfusions of packed red blood cells and fresh frozen plasma was significantly higher in patients with nosocomial infection compared with patients without nosocomial infection (P = .018 and P = .039). Blood products dose-dependently contributed to nosocomial infections. Transfusions of ≥ 7.5 units of red blood cells (odds ratio: 2.8) or ≥ 12.5 units of fresh frozen plasma (odds ratio: 3.27) were associated with nosocomial infections (P = .042 and P = .015). The infection-related mortality rate was 10.3%.

CONCLUSIONS

Blood product transfusions are associated with an increased rate of nosocomial infections, which contributes to higher morbidity and mortality.

Risk factors for bleeding and clinical implications in patients undergoing liver transplantation

INTRODUCTION

Advanced liver disease is characterized by prolonged global coagulation tests such as prothrombin time (PT). Using Model of End-stage Liver Disease (MELD) score-based allocation, many current transplant recipients show advanced end-stage liver disease with an elevated international normalized ratio (INR). The relationship between abnormalities in coagulation tests and the risk of bleeding has been recently challenged among liver disease patients. In this study we reassessed risk factors for bleeding and the clinical implications for patients who underwent orthotopic liver transplantation (OLT).

METHODS

We studied OLT patients between 2005 and 2011 excluding combined transplantations, retransplantations, or cases due to acute liver failure. We collected prospectively pre-OLT, during OLT, and post-OLT clinical and biochemical data to assess the risk for bleeding using linear regression models.

RESULTS

The strongest predictor of overall survival among 286 patients with a mean follow-up of 32 months was the number of blood transfusions (P = .005). The risk factor for bleeding during surgery investigated by multivariate analysis only showed the INR (P < .001) and the presence of ascites (P = .003) to independently correlate with the amount of blood transfusion. Receiver operation characteristics (ROC) analysis performed to determine the risk for massive blood transfusion (more than 6 units) revealed a cut-off value for INR ≥ 1.6. Appreciation of the operative field by the surgeon during the intervention as "wet" versus "dry", amounts of blood transfusion and fresh frozen plasma, and stay in the intensive care unit (ICU) and in the hospital were all significantly different (P < .001) for patients with INR <1.6 versus INR ≥ 1.6.

CONCLUSIONS

Bleeding during OLT affects the outcome. The risk is independently influenced by the presence of ascites (probably reflecting the degree portal hypertension) and an INR ≥ 1.6. To improve survival after OLT therapeutic interventions should be further explored to reduce the need for blood transfusions.

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.

Impact of pretransplant hepatic encephalopathy on liver posttransplantation outcomes

Patients with cirrhosis commonly experience hepatic encephalopathy (HE), a condition associated with alterations in behavior, cognitive function, consciousness, and neuromuscular function of varying severity. HE occurring before liver transplant can have a substantial negative impact on posttransplant outcomes, and preoperative history of HE may be a predictor of posttransplant neurologic complications. Even with resolution of previous episodes of overt or minimal HE, some patients continue to experience cognitive deficits after transplant. Because HE is one of the most frequent pretransplant complications, improving patient HE status before transplant may improve outcomes. Current pharmacologic therapies for HE, whether for the treatment of minimal or overt HE or for prevention of HE relapse, are primarily directed at reducing cerebral exposure to systemic levels of gut-derived toxins (e.g., ammonia). The current mainstays of HE therapy are nonabsorbable disaccharides and antibiotics. The various impacts of adverse effects (such as diarrhea, abdominal distention, and dehydration) on patient's health and nutritional status should be taken into consideration when deciding the most appropriate HE management strategy in patients awaiting liver transplant. This paper reviews the potential consequences of pretransplant HE on posttransplant outcomes and therapeutic strategies for the pretransplant management of HE.

Nutrition support and infections associated with hepatic resection and liver transplantation in patients with chronic liver disease

Malnutrition is common in liver cirrhotic patients who will undergo liver resection or liver transplantation. A precise evaluation of their nutrition status is thus difficult because of the presence of ascites and the edema caused by their impaired protein synthesis. Both perioperative enteral and parenteral nutrition have benefits in reducing the morbidity and mortality of liver surgery, and in general, oral nutrition supplements are recommended. Branched-chain amino acids (BCAAs) promote protein and glycogen synthesis and regulate immune system function. Synbiotics, a combination of pro- and prebiotics, is reported to enhance immune responses. Oral nutrition support with BCAAs, synbiotics, and an immune-enhancing diet have a beneficial effect on preventing the perioperative infections associated with hepatic resection or liver transplantation.

Analysis of infections in the first 3-month after living donor liver transplantation

AIM: To identify factors related to serious postoperative bacterial and fungal infections in the first 3 mo after living donor liver transplantation (LDLT).

METHODS: In the present study, the data of 207 patients from 2004 to 2011 were reviewed. The pre-, intra- and post-operative factors were statistically analyzed. All transplantations were approved by the ethics committee of West China Hospital, Sichuan University. Patients with definitely preoperative infections and infections within 48 h after transplantation were excluded from current study. All potential risk factors were analyzed using univariate analyses. Factors significant at a P < 0.10 in the univariate analyses were involved in the multivariate analyses. The diagnostic accuracy of the identified risk factors was evaluated using receiver operating curve.

RESULTS: The serious bacterial and fungal infection rates were 14.01% and 4.35% respectively. Enterococcus faecium was the predominant bacterial pathogen, whereas Candida albicans was the most common fungal pathogen. Lung was the most common infection site for both bacterial and fungal infections. Recipient age older than 45 years, preoperative hyponatremia, intensive care unit stay longer than 9 d, postoperative bile leak and severe hyperglycemia were independent risk factors for postoperative bacterial infection. Massive red blood cells transfusion and postoperative bacterial infection may be related to postoperative fungal infection.

CONCLUSION: Predictive risk factors for bacterial and fungal infections were indentified in current study. Pre-, intra- and post-operative factors can cause postoperative bacterial and fungal infections after LDLT.

Predictive Models and Algorithms for the Need of Transfusion Including Massive Transfusion in Severely Injured Patients

BACKGROUND: Despite improvements on how to resuscitate exsanguinating patients, one remaining key to improve outcome is to expeditiously and reproducibly identify patients most likely to require transfusion including massive transfusion (MT). This work summarizes yet developed algorithms/scoring systems for transfusion including MT in civilian and military trauma populations. METHODS: A systematic search of evidence was conducted utilizing OVID/MEDLINE (1966 to present) and the 'Medical Algorithms Project'. RESULTS AND CONCLUSIONS: The models developed suggest combinations of physiologic, hemodynamic, laboratory, injury severity and demographic triggers identified on the initial evaluation of the bleeding trauma patient. Many approaches use a combination of dichotomous variables readily accessible after arrival but others rely on time-consuming calculations or complex algorithms and may have limited real-time application. Weighted and more sophisticated systems including higher numbers of variables perform superior. A common limitation to all models is their retrospective nature, and prospective validations are urgently needed. Point-of-care viscoelastic testing may be an alternative to these systems.

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.

Preoperative anaemia and postoperative outcomes in non-cardiac surgery: a retrospective cohort study

BACKGROUND

Preoperative anaemia is associated with adverse outcomes after cardiac surgery but outcomes after non-cardiac surgery are not well established. We aimed to assess the effect of preoperative anaemia on 30-day postoperative morbidity and mortality in patients undergoing major non-cardiac surgery.

METHODS

We analysed data for patients undergoing major non-cardiac surgery in 2008 from The American College of Surgeons' National Surgical Quality Improvement Program database (a prospective validated outcomes registry from 211 hospitals worldwide in 2008). We obtained anonymised data for 30-day mortality and morbidity (cardiac, respiratory, CNS, urinary tract, wound, sepsis, and venous thromboembolism outcomes), demographics, and preoperative and perioperative risk factors. We used multivariate logistic regression to assess the adjusted and modified (nine predefined risk factor subgroups) effect of anaemia, which was defined as mild (haematocrit concentration >29-<39% in men and >29-<36% in women) or moderate-to-severe (≤29% in men and women) on postoperative outcomes.

FINDINGS

We obtained data for 227,425 patients, of whom 69,229 (30·44%) had preoperative anaemia. After adjustment, postoperative mortality at 30 days was higher in patients with anaemia than in those without anaemia (odds ratio [OR] 1·42, 95% CI 1·31-1·54); this difference was consistent in mild anaemia (1·41, 1·30-1·53) and moderate-to-severe anaemia (1·44, 1·29-1·60). Composite postoperative morbidity at 30 days was also higher in patients with anaemia than in those without anaemia (adjusted OR 1·35, 1·30-1·40), again consistent in patients with mild anaemia (1·31, 1·26-1·36) and moderate-to-severe anaemia (1·56, 1·47-1·66). When compared with patients without anaemia or a defined risk factor, patients with anaemia and most risk factors had a higher adjusted OR for 30-day mortality and morbidity than did patients with either anaemia or the risk factor alone.

INTERPRETATION

Preoperative anaemia, even to a mild degree, is independently associated with an increased risk of 30-day morbidity and mortality in patients undergoing major non-cardiac surgery.

FUNDING

Vifor Pharma.

Aprotinin versus tranexamic acid during liver transplantation: impact on blood product requirements and survival

BACKGROUND

Historically, orthotopic liver transplantation (OLT) has been associated with major blood loss and the need for blood product transfusions. Activation of the fibrinolytic system can contribute significantly to bleeding. Prophylactic administration of antifibrinolytic agents was found to reduce blood loss.

METHODS

The efficacy of two antifibrinolytic compounds--aprotinin (AP) and tranexamic acid (TA)--was compared in OLT. Four hundred consecutive OLTs were studied: 300 patients received AP and 100 received TA. Multivariate logistic regression analysis was used to identify independent predictors of intraoperative transfusion requirement and 1-year patient mortality.

RESULTS

There was no intergroup difference in intraoperative blood loss (1082±1056 vs. 1007±790 mL), red blood cell transfusion per patient (0.5±1.4 vs. 0.5±1.0), final hemoglobin (Hb) concentration (93±20 g/L vs. 95±22 g/L), the percentage of OLT cases requiring no blood product administration (80% vs. 82%), and 1-year survival (85.1% vs. 87.4%). Serum creatinine concentrations were also the same (116±55 vs. 119±36 μmol/L) 1 year after surgery. Two variables, starting Hb and phlebotomy, correlated with the two primary outcome measures (transfusion and 1-year survival).

CONCLUSIONS

In our experience, administration of AP was not superior to TA with regards to blood loss and blood product transfusion requirement during OLT. In addition, we found no difference between the groups in the 1-year survival rate and renal function. Furthermore, we suggest that starting Hb concentration should be considered when prioritizing patients on the waiting list and planning perioperative care for OLT recipients.

Intraoperative management of liver transplant patients

Liver transplantation for end-stage liver disease results in excellent outcomes. Patient and graft outcome is closely monitored on a national level, and 1-year survival is between 80% and 95%. Liver transplantation relies on a multidisciplinary approach, with close involvement of anesthesiologists and intensivists. However, intraoperative care of these patients remains inconsistent and is highly institution dependent. This brief-review article will focus on controversial topics of intraoperative care. Existing evidence on intraoperative monitoring, intraoperative fluid and transfusion management, electrolyte and glucose management, postoperative patient disposition, and, lastly, anesthesia team management will be reviewed.

Postliver transplant acute renal injury and failure by the RIFLE criteria in patients with normal pretransplant serum creatinine concentrations: a matched study

BACKGROUND

Acute renal injury (ARI) and acute renal failure (ARF) are serious complications after liver transplantation (LT). Few studies apply the risk, injury, function, loss, and end-stage criteria on the patients who have normal preoperative renal function. The aims of this study were to identify the incidence, risk factors, and impact of ARI and ARF in this patient population.

METHODS

After institutional review board approval, adult LT patients who had preoperative serum creatinine less than or equal to 1.5mmol/L were reviewed. Postoperative ARI and ARF were determined by the risk, injury, function, loss, and end-stage criteria. Risk factors were determined by multivariable regression. Postoperative outcomes were compared among patients with or without ARI or ARF.

RESULTS

Among 334 patients included the study, 20.4% and 18.0% had ARI or ARF in the first week after LT, respectively. Then 118 ARI or ARF patients were matched with patients without post-LT renal injury by gender, creatinine, and body mass index. Multivariable analysis showed that increased requirement of red blood cell transfusion (odds ratio [OR] 2.7-8.8, P<0.05), vasopressors (OR 2.2, P=0.018), and pre-LT albumin less than or equal to 3.5 mg/dL (OR: 2.8, P=0.003) as risk factors for post-LT ARI or ARF. Both ARI and ARF were associated with longer hospital stay and higher reoperation rate. ARF, but not ARI, was associated with higher 30-day graft failure and mortality rates.

CONCLUSION

Post-LT ARI or ARF occurred frequently in patients with normal preoperative renal function and was associated with both preoperative and intraoperative risk factors. Although both post-LT ARI and ARF are associated with significant post-LT morbidity, the impact of ARF is greater.

Risk factors for bleeding and transfusion during orthotopic liver transplantation

OBJECTIVE

While orthotopic liver transplantation (OLT) can be associated with haemorrhage, the risk factors for bleeding and transfusion remain difficult to predict. Perioperative transfusion has potentially deleterious side effects and impairs graft and patient survival. Preoperative identification of patients at high risk of bleeding is of clinical interest to manage perioperative transfusion and blood product storage.

STUDY DESIGN

Retrospective study.

PATIENTS AND METHODS

All OLT conducted between 2004 and 2008 in the University Hospital of Bordeaux were studied. Risk factors for bleeding greater than one blood volume and for massive red blood cell (RBC) transfusion were determined using univariate and multivariate analysis. Thresholds were determined with ROC curve analysis.

RESULTS

One hundred and forty-eight transplantations were studied. Preoperative haemoglobin and Child class A were independent protective risk factors for bleeding greater than one blood volume (OR 0.81 [0.67-0.98] and 0.27 [0.10-0.72], respectively). Preoperative Hb was a protective risk factor (OR 0.71 [0.58-0.88]) whereas history of oesophageal varicose bleeding was a risk factor (OR 4.67 [1.45-15.05]) for transfusion of more than eight RBC.

CONCLUSION

Risk factors for bleeding and transfusion during OLT identified in this study were of little clinical usefulness so blood products should always be available during the procedure.

Prospective Identification of Patients at Risk for Massive Transfusion: An Imprecise Endeavor

Most retrospective studies evaluating fresh-frozen plasma:packed red blood cell ratios in trauma patients requiring massive transfusion (MT) are limited by survival bias. As prospective resource-intensive studies are being designed to better evaluate resuscitation strategies, it is imperative that patients with a high likelihood of MT are identified early. The objective of this study was to develop a predictive model for MT in civilian trauma patients. Patients admitted to the University of Alabama at Birmingham Trauma Center from January 2005 to December 2007 were selected. Admission clinical measurements, including blood lactate 5 mMol/L or greater, heart rate greater than 105 beats/min, international normalized ratio greater than 1.5, hemoglobin 11g/dL or less, and systolic blood pressure less than 110 mmHg, were used to create a predictive model. Sensitivity (Sens), specificity (Spec), positive predictive value (PPV), and negative predictive value (NPV) were calculated for all possible combinations of clinical measurements as well as each measure individually. A total of 6638 patients were identified, of whom 158 (2.4%) received MT. The best-fit predictive model included three or more positive clinical measures (Sens: 53%, Spec: 98%, PPV: 33%, NPV: 99%). There was increased PPV when all clinical measurements were positive (Sens: 9%, Spec: 100%, PPV: 86%, NPV: 98%). All combinations or clinical measures alone yielded lower predictive probability. Using these emergency department clinical measures, a predictive model to successfully identify civilian trauma patients at risk for MT was not able to be constructed. Given prospective identification of patients at risk for MT remains an imprecise undertaking, appropriate resources to support these efforts will need to be allocated for the completion of these studies.

Bleeding and clotting disorders in pediatric liver disease

The coagulopathy of liver disease in pediatric patients presents an unusual set of challenges. Little pediatric data have been published, so this review is based largely on adult studies. There is a precarious balance between deficiencies of clotting factors and anticoagulation factors in liver disease that result in abnormal prothrombin time (PT) and activated partial thromboplastin time (aPTT) tests that would suggest a bleeding tendency, yet the patients can form a clot and are at risk of thromboembolic disease. Attention has centered on thromboelastography and thrombin-generation assays to clarify the patient's ability to control bleeding, but these tests are not routinely available to many treating physicians.

Role of nutrition in the management of hepatic encephalopathy in end-stage liver failure

Malnutrition is common in patients with end-stage liver failure and hepatic encephalopathy, and is considered a significant prognostic factor affecting quality of life, outcome, and survival. The liver plays a crucial role in the regulation of nutrition by trafficking the metabolism of nutrients, their distribution and appropriate use by the body. Nutritional consequences with the potential to cause nervous system dysfunction occur in liver failure, and many factors contribute to malnutrition in hepatic failure. Among them are inadequate dietary intake, malabsorption, increased protein losses, hypermetabolism, insulin resistance, gastrointestinal bleeding, ascites, inflammation/infection, and hyponatremia. Patients at risk of malnutrition are relatively difficult to identify since liver disease may interfere with biomarkers of malnutrition. The supplementation of the diet with amino acids, antioxidants, vitamins as well as probiotics in addition to meeting energy and protein requirements may improve nutritional status, liver function, and hepatic encephalopathy in patients with end-stage liver failure.

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.

Considerations on the impact of hepatic encephalopathy treatments in the pretransplant setting

Hepatic encephalopathy (HE) is a common complication of acute and chronic liver disease associated with exposure of brain tissue to excessive levels of ammonia produced by intestinal bacteria. Clinical manifestations range from subtle neurologic abnormalities to coma. Because development of HE can reduce survival probability, guidelines for evaluating patients for liver transplantation suggest that patients who develop HE should be considered for transplantation. Various patient factors before transplantation, including the presence of HE and reduced nutritional status, may increase the risk of poor outcomes after transplantation. Therefore, effective management of HE before transplantation, while minimizing the potential impact of negative predictive factors, may improve transplantation outcomes. The most common HE treatments are directed toward reducing systemic ammonia levels, thereby reducing brain exposure to this neurotoxin. The administration of nonabsorbable disaccharides is considered as a first-line therapy for HE, and the antibiotics neomycin and metronidazole are frequently administered, despite a lack of clinical data supporting their efficacy. These agents are associated with adverse events that may reduce nutritional status in patients awaiting transplantation and could contribute to poor posttransplantation outcomes. The nonsystemic antibiotic rifaximin has demonstrated efficacy for the treatment of HE and has a favorable safety profile. Given these data, nonsystemic antibiotics may also provide a safe and effective option for treating HE in the pretransplant setting. This article reviews treatments for HE and the potential impact these treatments may have on pretransplantation status of patients awaiting liver transplantation and on posttransplantation outcomes.

Rebalanced hemostasis in patients with liver disease: evidence and clinical consequences

Patients with liver disease frequently acquire a complex disorder of hemostasis secondary to their disease. Routine laboratory tests such as the prothrombin time and the platelet count are frequently abnormal and point to a hypocoagulable state. With more sophisticated laboratory tests it has been shown that patients with liver disease may be in hemostatic balance as a result of concomitant changes in both pro- and antihemostatic pathways. Clinically, this rebalanced hemostatic system is reflected by the large proportion of patients with liver disease who can undergo major surgery without any requirement for blood product transfusion. However, the hemostatic balance in the patient with liver disease is relatively unstable as evidenced by the occurrence of both bleeding and thrombotic complications in a significant proportion of patients. Although it is still common practice to prophylactically correct hemostatic abnormalities in patients with liver disease before invasive procedures by administration of blood products guided by the prothrombin time and platelet count, we believe that this policy is not evidence-based. In this article, we will provide arguments against the traditional concept that patients with liver failure have a hemostasis-related bleeding tendency. Consequences of these new insights for hemostatic management will be discussed.

Rotation thromboelastometry detects thrombocytopenia and hypofibrinogenaemia during orthotopic liver transplantation

BACKGROUND

Orthotopic liver transplantation can be associated with haemorrhage, particularly in patients with severe liver dysfunction. We assessed the value of rotation thromboelastometry (ROTEM) to monitor coagulation in the operating theatre, its correlation with routine laboratory findings, and its ability to guide platelet (Plt) and fibrinogen (Fg) transfusion.

METHODS

Twenty-three patients were included in this prospective observational study. Laboratory tests and ROTEM tests (EXTEM, INTEM, FIBTEM, and APTEM) were performed six times during the procedure. Correlations between laboratory findings and ROTEM parameters were sought. Thresholds for ROTEM parameters were determined with receiver-operating characteristic (ROC) curve analysis according to Plt count and Fg levels.

RESULTS

Clot amplitude at 10 min (A10) of EXTEM was well correlated with Plt count and Fg levels (R(2)=0.46 and 0.52, respectively, P<0.0001). FIBTEM A10 was correlated with Fg (R(2)=0.55, P<0.0001). ROC analysis showed that EXTEM A10 with a threshold of 29 mm predicted thrombocytopenia with a sensitivity of 79% and a specificity of 60%, and a threshold of 26 mm predicted hypofibrinogenaemia with a sensitivity of 83% and a specificity of 75%.

CONCLUSIONS

ROTEM is useful for the global assessment of coagulation in the operating theatre. EXTEM was the most informative for assessing the whole coagulation process and A10 showed value in guiding Plt and Fg transfusion.

Predictors of blood transfusion requirement in elective liver resection

BACKGROUND

Liver resection remains major surgery frequently requiring intra-operative blood transfusion. Patients are typically over cross-matched, and with blood donor numbers falling, cross-matching and transfusion policies need rationalizing.

AIM

To identify predictors of peri-operative blood transfusion.

METHODS

A retrospective review of elective hepatic resections over a 4-year period was performed. Twenty-six variables including clinicopathological variables and intra-operative data were collated, together with the number of units of blood cross-matched and transfused in the immediate peri-operative period (48 h). Multivariate regression analysis was performed to identify independent predictors of blood transfusion, and a Risk Score for transfusion constructed.

RESULTS

Five hundred and eighty-nine patients were included in the study, and were cross-matched with a median 10 units of blood. Seventeen per cent of patients received a blood transfusion; median transfusion when required was 2 units. Regression analysis identified seven factors predictive of transfusion: haemoglobin <12.5 g/dL, pre-operative biliary drainage, coronary artery disease, largest tumour >3.5 cm, cholangiocarcinoma, redo resection and extended resection (5+ segments). Patients were stratified into high or low risk of transfusion based on Risk Score with a sensitivity of 73% [receiver-operating characteristic (ROC) 0.77].

CONCLUSIONS

Patients undergoing elective liver resection are over-cross-matched. Patients can be classified into high and low risk of transfusion using a Risk Score, and cross-matched accordingly.

[The application of MELD score in patients submitted to liver transplantation: a retrospective analysis of survival and the predictive factors in the short and long term]

BACKGROUND

The model for end-stage liver disease (MELD) was developed to predict short-term mortality in patients with cirrhosis. There are few reports studying the correlation between MELD and long-term posttransplantation survival.

AIM

To assess the value of pretransplant MELD in the prediction of posttransplant survival.

METHODS

The adult patients (age >18 years) who underwent liver transplantation were examined in a retrospective longitudinal cohort of patients, through the prospective data base. We excluded acute liver failure, retransplantation and reduced or split-livers. The liver donors were evaluated according to: age, sex, weight, creatinine, bilirubin, sodium, aspartate aminotransferase, personal antecedents, brain death cause, steatosis, expanded criteria donor number and index donor risk. The recipients' data were: sex, age, weight, chronic hepatic disease, Child-Turcotte-Pugh points, pretransplant and initial MELD score, pretransplant creatinine clearance, sodium, cold and warm ischemia times, hospital length of stay, blood requirements, and alanine aminotransferase (ALT >1,000 UI/L = liver dysfunction). The Kaplan-Meier method with the log-rank test was used for the univariable analyses of posttransplant patient survival. For the multivariable analyses the Cox proportional hazard regression method with the stepwise procedure was used with stratifying sodium and MELD as variables. ROC curve was used to define area under the curve for MELD and Child-Turcotte-Pugh.

RESULTS

A total of 232 patients with 10 years follow up were available. The MELD cutoff was 20 and Child-Turcotte-Pugh cutoff was 11.5. For MELD score > or =20, the risk factors for death were: red cell requirements, liver dysfunction and donor's sodium. For the patients with hyponatremia the risk factors were: negative delta-MELD score, red cell requirements, liver dysfunction and donor's sodium. The regression univariated analyses came up with the following risk factors for death: score MELD > or = 25, blood requirements, recipient creatinine clearance pretransplant and age donor > or =50. After stepwise analyses, only red cell requirement was predictive. Patients with MELD score < 25 had a 68.86%, 50,44% and 41,50% chance for 1, 5 and 10-year survival and > or =25 were 39.13%, 29.81% and 22.36% respectively. Patients without hyponatremia were 65.16%, 50.28% and 41,98% and with hyponatremia 44.44%, 34.28% and 28.57% respectively. Patients with IDR > or =1.7 showed 53.7%, 27.71% and 13.85% and index donor risk <1.7 was 63.62%, 51.4% and 44.08%, respectively. Age donor > 50 years showed 38.4%, 26.21% and 13.1% and age donor < or =50 years showed 65.58%, 26.21% and 13.1%. Association with delta-MELD score did not show any significant difference. Expanded criteria donors were associated with primary non-function and severe liver dysfunction. Predictive factors for death were blood requirements, hyponatremia, liver dysfunction and donor's sodium.

CONCLUSION

In conclusion MELD over 25, recipient's hyponatremia, blood requirements, donor's sodium were associated with poor survival.

Liver donor's age and recipient's serum creatinine predict blood component use during liver transplantation

BACKGROUND

Excessive use of blood components during liver transplantation should be avoided because it has been associated with poor outcomes and it may stress blood bank resources.

STUDY DESIGN AND METHODS

To determine preoperative predictors of excessive transfusion requirements in patients undergoing liver transplantation, the clinical records of 126 consecutive adult patients undergoing primary liver transplantation were retrospectively reviewed. Outcome variables included number of red blood cells (RBCs), plasma, and plateletpheresis components intraoperatively transfused. Univariate analyses of the following predictor variables were performed: recipient age, sex, ethnicity, height/weight, Model for End Stage Liver Disease score, year of transplant, previous abdominal surgery, hepatoma, wait-list time, standard recipient laboratory values obtained immediately before transplantation, cold ischemia time, donor age, sex, and height/weight. Multivariate analysis using logistic regression was used to build a model that best predicted how many blood components should be available before transplant.

RESULTS

Donor age of more than 50 years old (odds ratio [OR], 2.8 95% confidence interval [CI], 1.3-6.0), and recipient serum creatinine (SCr) level of more than 1.3 mg/dL (OR, 3.8 95% CI, 1.6-8.9) were the only variables found to be predictive of RBC use in multivariate analysis. This model accurately predicted the use of more than 10 units of RBCs 79% of cases. Having both adverse factors present resulted in using more than one box in 80% of cases as compared to 44% of cases where only one or no adverse factor was present (p = 0.002). Further analyses showed a direct correlation between the number of RBCs transfused and plasma (r = 0.93) and plateletpheresis components (r = 0.74) transfused. [Corrections added after online publication 22-Jul-2009: OR updated from 3.8 to 2.8; CI from 1.6-8.9 to 1.3-6.0; OR from 2.8-3.8.]

CONCLUSION

Liver donor's age and recipient's SCr are important in preoperatively predicting blood use during liver transplantation.

Dependence of platelet function on underlying liver disease in orthotopic liver transplantation

OBJECTIVE

The purpose of the present study was to explore the platelet function during the perioperative period of orthotopic liver transplantation (OLT) due to the underlying liver disease.

METHODS

The blood coagulation parameters, platelet surface markers and the determination of platelet aggregation were analyzed in 34 patients who underwent OLT. Blood samples were drawn preoperatively, anhepatic, 10 min and 1 hour after reperfusion, 1 day, 3 and 7 days postoperatively. Conventional coagulation screens, thrombopoietin (TPO) serum levels, P-selectin, GPIIb/IIIa and GPIb binding sites on the surface of platelets as evaluated by flow cytometry and platelet aggregation response were measured.

RESULTS

Coagulation factors, maximum aggregation and rate of aggregation were significantly different before transplantation due to the underlying liver disease. Further we found a markedly depressed GPIIb/IIIa and P-selectin expression and a reduced rate of aggregation in all patients throughout the study. In contrast maximum aggregation of platelets was restored on the third day after reperfusion without intergroup differences and almost comparable to healthy controls. An inverse correlation was found between peripheral platelet count pre-transplantation and peak TPO concentrations one weak post-transplantation.

CONCLUSIONS

In the entire process of OLT, coagulation factors, maximum aggregation and rate of platelet aggregation depend on the surgical phases during transplantation and on the underlying liver disease. The data obtained in this study might contribute to a better understanding of the pathophysiology and assessment of bleeding risk in OLT.

Application of the McCluskey Index to predict blood product requirements during liver transplantation

BACKGROUND

A recent study proposed a risk index (McCluskey index) based on 7 parameters to identify the transfusion needs of patients during surgery and in the first 24 hours postoperation. The initial objective of our study was to validate this predictor for blood product transfusions.

PATIENTS AND METHODS

We undertook a retrospective, observational study of all liver transplant patients between January 1, 2005 and December 31, 2006. The following variables were recorded for each patient: age, gender, patient comorbidity, biochemical values prior to liver transplantation, and transfusion needs.

RESULTS

Comparing the transfusion needs of those patients with scores <5 with those of scores >/=5, we observed significant differences in terms of the use of red blood cell concentrates, plasma, and platelets, both during the first 24 hours and in the total number. The index sensitivity was 80% (95% confidence interval [CI]: 71.23-88.76), with a specificity of 84.21% (95% CI: 67.81-100), where the positive predictive value was 95.52% (95% CI: 90.57-100.4) and the negative predictive value was 50% (95% CI: 32.67-67.32).

CONCLUSION

The McCluskey index showed sufficient sensitivity and specificity to predict which patients will require a massive transfusion.

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.