Intraoperative massive transfusion decreases survival after liver transplantation

Validation of 5 models predicting transfusion, bleeding, and mortality in liver transplantation: an observational cohort study

BACKGROUND

Historically, orthotopic liver transplantation (OLT) has been associated with massive blood loss, blood transfusion and morbidity. In order to predict such outcomes five nomograms have been published relating to transfusions and morbidity associated with OLTs. These nomograms, developed on the basis of three cohorts of patients consisting of 406, 750, and 800 having undergone OLTs, aimed to predict a transfusion of ≥1 red blood cell unit (RBC), a transfusion of >2 RBC units, a blood loss of >900 ml, as well as one-month and one-year survival rates. The aim of this study was to validate these five nomograms in a contemporary, independent cohort of patients.

METHODS

Five nomograms were previously developed based on 406, 750, and 800 OLTs. In this study we performed a temporal validation of these nomograms on contemporary patients that consisted of three cohorts of 800, 250, and 200 OLTs. Logistic regression coefficients from the historic development cohorts were applied to the three contemporary temporal validation cohorts.

RESULTS

The most accurate nomogram was able to predict transfusion of ≥1 RBC units with an area under the curve (AUC) was 0.91. The second-best nomogram was able to predict bleeding of >900 ml with an AUC of 0.70. T he AUC of the third nomogram (transfusion of >2 RBC units) was 0.70. However, is temporal validation was suboptimal, due to a low prevalence of OLTs transfused with >2 RBC units. The last 2 nomograms exhibited clearly suboptimal AUC values of 0.54 and 0.61.

CONCLUSION

Two of the five nomograms predict blood transfusion and blood loss with excellent accuracy. Transfusion of ≥1 RBC unit and blood loss of >900 ml can be predicted on the basis of these nomograms. However, these nomograms are not accurate to predict one-month and one-year survival rates. These results should be further cross-validated, ideally prospectively, in additional external independent cohorts.

Using novel PF4-dependent P-selectin expression assay to diagnose heparin-induced thrombocytopaenia postliver transplantation

Heparin-induced thrombocytopaenia (HIT) is a well-known adverse event associated with the use of heparin products. HIT may be difficult to diagnose in patients following liver transplantation as patients routinely require massive transfusion support and immunosuppression. As an alternative or adjunctive to the serotonin release assay, the PF4-dependent P-selectin expression assay (PEA) may be a useful diagnostic test in the determination of HIT in this patient population. In this case, we describe a 63-year-old man who had an orthotopic liver transplant that was complicated by HIT that was diagnosed using the PEA.

BAR Score Performance in Predicting Survival after Living Donor Liver Transplantation: A Single-Center Retrospective Study

METHODS

146 adult liver transplant recipients were included. Univariate and multivariate analyses were used to determine the independent predictors of survival at 3 months, 1 year, and 5 years. The receiver operating characteristic (ROC) curve for the BAR score was plotted, and the area under the ROC curve (AUROC) was calculated. Kaplan-Meier curve and log-rank test were used to compare survival above and below the best cutoff values.

RESULTS

The mean age was 52.45 ± 8.54 years, and 59.6% were males. The survival rates were 89, 78.8, and 72% at 3 months, 1 year, and 5 years, respectively. The BAR score demonstrated a clinically significant value in the prediction of 3-month (AUROC = 0.89), 1-year (AUROC = 0.76), and 5-year survival (AUROC = 0.71). Among the investigated factors associated with survival, BAR score <10 points was the only independent predictor of 3-month (OR 7.34, p < 0.0001), 1-year (OR 3.37, p=0.001), and 5-year survival (OR 2.83, p=0.044).

CONCLUSIONS

BAR is a simple and easily applicable scoring system that could significantly predict short- and long-term survival after LDLT. A large multicenter study is warranted to validate our results in the Egyptian population.

Protocol for a prospective double-blind, randomised, placebo-controlled feasibility trial of octreotide infusion during liver transplantation

INTRODUCTION

Liver transplantation is a complex operation that can provide significant improvements in quality of life and survival to the recipients. However, serious complications are common and include major haemorrhage, hypotension and renal failure. Blood transfusion and the development of acute kidney injury lead to both short-term and long-term poor patient outcomes, including an increased risk of death, graft failure, length of stay and reduced quality of life. Octreotide may reduce the incidence of renal dysfunction, perioperative haemorrhage and enhance intraoperative blood pressure. However, octreotide does have risks, including resistant bradycardia, hyperglycaemia and hypoglycaemia and QT prolongation. Hence, a randomised controlled trial of octreotide during liver transplantation is needed to determine the cost-efficacy and safety of its use; this study represents a feasibility study prior to this trial.

METHODS AND ANALYSIS

We describe a multicentre, double-blind, randomised, placebo-controlled feasibility study of continuous infusion of octreotide during liver transplantation surgery. We will recruit 30 adult patients at two liver transplant centres. A blinded infusion during surgery will be administered in a 2:1 ratio of octreotide:placebo. The primary outcomes will determine the feasibility of this study design. These include the recruitment ratio, correct administration of blinded study intervention, adverse event rates, patient and clinician enrolment refusal and completion of data collection. Secondary outcome measures of efficacy and safety will help shape future trials by assessing potential primary outcome measures and monitoring safety end points. No formal statistical tests are planned. This manuscript represents study protocol number 1.3, dated 2 June 2021.

ETHICS AND DISSEMINATION

This study has received Research Ethics Committee approval. The main study outcomes will be submitted to an open-access journal.

TRIAL SPONSOR

The Joint Research Office, University College London, UK.Neither the sponsor nor the funder have any role in study design, collection, management, analysis and interpretation of data, writing of the study report or the decision to submit the report for publication.

TRIAL REGISTRATION

The study is registered with ClinicalTrials.gov (NCT04941911) with recruitment due to start in August 2021 with anticipated completion in July 2022.

CLINICAL TRIALS UNIT

Surgical and Interventional Group, Division of Surgery & Interventional Science, University College London.

Association of acidosis with coagulopathy and transfusion requirements in liver transplantation

The relationship between acidosis and coagulopathy has long been described in vitro and in trauma patients, but not yet in orthotopic liver transplantation (OLT). The association of metabolic acidosis with coagulopathy and with transfusion requirements was evaluated in patients submitted to OLT. Changes in acid-base and coagulation parameters were analyzed by repeated measures. Regression analyses [adjusted for sex, age, model for end stage liver disease (MELD) score, and baseline values of hemoglobin, fibrinogen, international normalized ratio, platelets] determined the association of acid-base parameters with coagulation markers and transfusion requirement. We included 95 patients, 66% were male, 49.5% of the patients had hepatocellular carcinoma and the mean MELD score was 20.4 (SD 8.9). The values of all the coagulation and acid-base parameters significantly changed during OLT, particularly in the reperfusion phase. After adjustments for baseline parameters, the decrease in pH and base excess (BE) values were associated with a decrease in fibrinogen levels (mean decrease of fibrinogen level = 14.88 mg/dL per 0.1 unit reduction of pH values and 3.6 mg/dL per 1 mmol/L reduction of BE levels) and an increase in red blood cells transfusion (2.16 units of RBC per 0.1 unit reduction of pH and 0.38 units of RBC per 1 mmol/L reduction of BE levels). Among multiple factors potentially associated with adverse outcomes, decreasing pH levels were independently associated with the length of hospitalization but not with in-hospital mortality. Metabolic acidosis is independently associated with decreased fibrinogen levels and increased intraoperative transfusion requirement during OLT. Awareness of that association may improve treatment strategies to reduce intraoperative bleeding risk in OLT.

The effect of a viscoelastic-guided bleeding algorithm implementation on blood products use in adult liver transplant patients. A propensity score-matched before-after study

BACKGROUND

Perioperative blood products transfusion is correlated with increased morbidity and mortality in liver transplantation (LTx). The objectives of our study are to assess the effect of a standardized viscoelastic test (VET)-guided bleeding management algorithm implementation on intraoperative bleeding, allogenic blood products and factor concentrates requirements and on early postoperative complications in LTx.

METHODS

Retrospective before-after study comparing two matched cohorts of patients undergoing LTx before (control cohort) and after (intervention cohort) the implementation of a VET-based bleeding algorithm in a single center academic hospital.

RESULTS

After propensity score matching, we included 94 patients in each cohort. Patients in intervention cohort received significantly less blood products, fresh frozen plasma (FFP), and cryoprecipitate (p < 0.001 for each), while the amount of fibrinogen concentrate used was significantly higher (p < 0.001). Postoperatively, intervention cohort patients had significantly lower postoperative hemoglobin and fibrinogen levels and longer prothrombin time compared to control cohort. There were no significant differences in red blood cells transfusions, intraoperative bleeding, early postoperative complications, and short term survival.

CONCLUSIONS

The implementation of a VET-guided bleeding algorithm decreases allogenic blood products requirements, mainly FFP use and allows a more restrictive management of coagulopathy in patients with chronic liver disease undergoing LTx.

Extended Adhesion-Sparing Liver Eversion during Kasai Portoenterostomy for Infants with Biliary Atresia

Background: Despite the fact that Kasai portoenterostomy (KPE) is the primary treatment for biliary atresia (BA), liver transplantation (LT) remains the ultimate surgery for two-thirds of these patients. Their true survival rate with the native liver reflects the original KPE and the burden of post-operative complications. We report an original modification of the adhesion-sparing liver eversion (ASLE) technique during KPE that facilitates the total native hepatectomy at time of transplantation. Methods: All consecutive patients with BA who underwent KPE at our department and subsequent LT at Paediatric Liver Transplant Centre at Papa Giovanni XXIII Hospital between 2010–2018 were retrospectively enrolled. All patients underwent ASLE during KPE. Patients’ demographic data, type of KPE, total transplant time (TTT), hepatectomy time (HT), intra-operative packed red blood cells and plasma transfusions, intra- and post-operative complications were noted. Results: 44 patients were enrolled. Median TTT and HT were 337 and 57 min, respectively. The median volume of packed red blood cell transfusion was 95 mL. No patients presented bowel perforation during the procedure or in the short post-operative course. No mortality after LT was recorded. Conclusions: In addition to the well-known advantages of the standard liver eversion technique, ASLE reduces the formation of intra-abdominal adhesions, lowering significantly the risk of bowel perforation and bleeding when liver transplantation is performed for failure of KPE.

Perioperative blood transfusion decreases long-term survival in pediatric living donor liver transplantation

BACKGROUND

The impact of perioperative blood transfusion on short- and long-term outcomes in pediatric living donor liver transplantation (PLDLT) must still be ascertained, mainly among young children. Clinical and surgical postoperative complications related to perioperative blood transfusion are well described up to three months after adult liver transplantation.

AIM

To determine whether transfusion is associated with early and late postoperative complications and mortality in small patients undergoing PLDLT.

METHODS

We evaluated the effects of perioperative transfusion on postoperative complications in recipients up to 20 kg of body weight, submitted to PLDLT. A total of 240 patients were retrospectively allocated into two groups according to postoperative complications: Minor complications (n = 109) and major complications (n = 131). Multiple logistic regression analysis identified the volume of perioperative packed red blood cells (RBC) transfusion as the only independent risk factor for major postoperative complications. The receiver operating characteristic curve was drawn to identify the optimal volume of the perioperative RBC transfusion related to the presence of major postoperative complications, defining a cutoff point of 27.5 mL/kg. Subsequently, patients were reallocated to a low-volume transfusion group (LTr; n = 103, RBC ≤ 27.5 mL/kg) and a high-volume transfusion group (HTr; n = 137, RBC > 27.5 mL/kg) so that the outcome could be analyzed.

RESULTS

High-volume transfusion was associated with an increased number of major complications and mortality during hospitalization up to a 10-year follow-up period. During a short-term period, the HTr showed an increase in major infectious, cardiovascular, respiratory, and bleeding complications, with a decrease in rejection complications compared to the LTr. Over a long-term period, the HTr showed an increase in major infectious, cardiovascular, respiratory, and minor neoplastic complications, with a decrease in rejection complications. Additionally, Cox hazard regression found that high-volume RBC transfusion increased the mortality risk by 3.031-fold compared to low-volume transfusion. The Kaplan-Meier survival curves of the studied groups were compared using log-rank tests and the analysis showed significantly decreased graft survival, but with no impact in patient survival related to major complications. On the other hand, there was a significant decrease in both graft and patient survival, with high-volume RBC transfusion.

CONCLUSION

Transfusion of RBC volume higher than 27.5 mL/kg during the perioperative period is associated with a significant increase in short- and long-term postoperative morbidity and mortality after PLDLT.

Association between intraoperative rotational thromboelastometry or conventional coagulation tests and bleeding in liver transplantation: an observational exploratory study

INTRODUCTION

Liver transplantation is associated with major blood loss and transfusions. Our objective was to evaluate the association between coagulation results (rotational thromboelastometry (ROTEM) and conventional coagulation tests) and intraoperative bleeding or perioperative red blood cell (RBC) transfusions in liver transplantation.

METHODS

We measured ROTEM values and conventional coagulation tests at the beginning of surgery, after graft reperfusion and at the end of surgery. We did bivariate correlation and multivariable regression analyses to explore the association between test results and either intraoperative bleeding or perioperative RBC transfusions.

RESULTS

We enrolled 75 consecutive patients. Median [Q1-Q3] intraoperative blood loss was 1400 mL [675-2300] and 59% of patients did not receive any RBC transfusion either intraoperatively or postoperatively. In multivariable analyses, FIBTEM maximal clot firmness (MCF) measured at the beginning of surgery was associated with lower intraoperative blood loss (ß = -106 mL for each mm; 95% CI, -203 to -9 mL). Both a higher haemoglobin concentration (multiplicative factor = 0.89 for each g/L; 95% CI, 0.84 to 0.95) and FIBTEM MCF measured at the end of surgery (multiplicative factor = 0.68 for each mm; 95% CI, 0.48 to 0.95) were associated with fewer postoperative RBC transfusions.

CONCLUSION

FIBTEM MCF was strongly associated with intraoperative blood loss and postoperative transfusions while other coagulation results were not. This study might inform future clinical trials on ROTEM-based interventions in liver transplantation.

STUDY REGISTRATION

Clinical Trials.gov: NCT02356068.

Accuracy of the BAR score in the prediction of survival after liver transplantation

INTRODUCTION AND AIM

The Balance of Risk (BAR) Score, a simple scoring system that combines six independent donor and recipient variables to predict outcome after liver transplantation (LT), was validated in a large U.S./European cohort of patients. This study aims to assess the performance of the BAR score to predict survival after liver transplantation and determine the factors associated with short and long-term survival in Latin-American patients.

MATERIAL AND METHODS

A retrospective cohort study was performed in 194 patients [112 (55.4%) males; mean age 52±14 years] who underwent 202 LT during the period 2003-2015. Demographic, clinical, pathological and surgical variables, as well as mortality and survival rates, were analyzed. The BAR score was investigated through a receiver operating characteristics (ROC) curve with the calculation of the area under the curve (AUC) to evaluate the predictive score power for 3-month, 1 and 5-year mortality in a matched donor-recipient cohort. Youden index was calculated to identify optimal cutoff points.

RESULTS

The AUC of BAR score in predicting 3-month, 1-year and 5-year mortality were 0.755 (CI95% 0.689-0.812), 0.702 (CI95% 0.634-0.764) and 0.610 (CI95% 0.539-0.678) respectively. The best cut-off point was a BAR score ≥15 points. In the multivariate analysis BAR score <15 was associated with higher survival rates at 3 months and 1 and 5-years.

CONCLUSIONS

BAR score <15 points is an independent predictor of better short and long-term survival in Latin-American patients undergoing LT. The BAR scoring system has an adequate diagnostic capacity allowing to predict 3 and 12-month mortality.

Liver Transplantation

The field of liver transplantation has changed since the MELD scoring system became the most widely used donor allocation tool. Due to the MELD-based allocation system, sicker patients with higher MELD scores are being transplanted. Persistent organ donor shortages remain a challenging issue, and as a result, the wait-list mortality is a persistent problem for most of the regions. This chapter focuses on deceased donor and live donor liver transplantation in patients with complications of portal hypertension. Special attention will also be placed on donor-recipient matching, perioperative management of transplant patients, and the impact of hepatic hemodynamics on transplantation.

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.

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

OBJECTIVE

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

DESIGN

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

SETTING

One community hospital.

PARTICIPANTS

The study comprised 686 patients who underwent 750 consecutive OLTs.

INTERVENTION

None.

MEASUREMENTS AND MAIN RESULTS

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

CONCLUSION

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

Utility of prothrombin complex concentrate as first-line treatment modality of coagulopathy in patients undergoing liver transplantation: A propensity score-matched study

BACKGROUND

Transfusion management during liver transplantation (LT) is aimed at reducing blood loss and allogeneic transfusion requirements. Although prothrombin complex concentrate (PCC) has been used satisfactorily in various bleeding disorders, studies on its safety, and efficacy during LT are limited.

METHODS

A retrospective chart review of adult patients who underwent living donor LT at a single institute between October 2016 and January 2018 was carried out. The safety and efficacy of PCC in reducing transfusion requirements intraoperatively in patients who received PCC were compared with patients who did not receive PCC. A propensity score-matching technique was used, at a 1:1 ratio, to remove selection bias.

RESULTS

After completing the 1:1 propensity score-matched analysis, 60 pairs of patients were identified. The use of PCC was associated with significantly decreased red blood cell transfusion requirements (6.2 ± 4.1 vs 8.23 ± 5.18, P < 0.001) and fresh frozen plasma transfusion requirements (2.6 ± 2 vs 6.18 ± 4.1, P < 0.001). The number of patients developing postoperative hemorrhagic complications was higher in the non-PCC group.

CONCLUSIONS

During LT, the use of PCC led to decreased transfusion requirements. No thromboembolic complications related to PCC were noted in this series.

Albumin-Bilirubin Score for Predicting Post-Transplant Complications Following Adult-to-Adult Living Donor Liver Transplantation

Background

Albumin-Bilirubin (ALBI) grade has been evaluated as an objective method to assess liver function and predict postoperative complications, particularly after hepatectomy in patients with hepatocellular carcinoma (HCC). However, ALBI grade was rarely used in evaluation in living donor liver transplantation (LDLT).

Material/Methods

Between March 2005 and November 2015, 272 consecutive patients undergoing right-lobe LDLT were enrolled in this study. According to the ALBI score used to evaluate recipients preoperatively, those patients were divided into 3 grades (I, II, and III). Demographic findings and the post-operative complication rates were collected and compared among groups.

Results

The proportions of massive blood cell transfusions were different among those 3 grades (p<0.05). The patients in grade III had a higher risk of bacterial pneumonia and early allograft dysfunction (EAD) compared to grade I (p=0.029 and p=0.038, respectively) and grade II (p=0.006 and p=0.007, respectively). The area under the receiver operating characteristic curve of ALBI, Child-Pugh, and MELD for predicting 30-day mortality were 0.702 (95% CI: 0.644–0.756), 0.669 (95% CI: 0.580–0.697, p=0.510, versus ALBI grade), and 0.540 (95% CI: 0.580–0.697, p=0.144, versus ALBI grade), respectively.

Conclusions

ALBI grade was a good index for predicting post-operative complications and had a predictive ability similar to those of the Child-Pugh classification and MELD score.

Perioperative Single-Donor Platelet Apheresis and Red Blood Cell Transfusion Impact on 90-Day and Overall Survival in Living Donor Liver Transplantation

Background:

Although many previous studies have confirmed that perioperative blood transfusion is associated with poor outcomes after liver transplantation (LT), few studies described the influence of single-donor platelet apheresis transfusion in living donor LT (LDLT). This study aimed to assess the effect of blood products on outcomes for LDLT recipients, focusing on apheresis platelets.

Methods:

This retrospective study included 126 recipients who underwent their first adult-to-adult LDLT. Twenty-four variables including consumption of blood products of 126 LDLT recipients were assessed for their link to short-term outcomes and overall survival. Kaplan-Meier survival curve and the log-rank test were used for recipient survival analysis. A multivariate Cox proportional-hazard model and a propensity score analysis were applied to adjust confounders after potential risk factors were identified by a univariate Cox analysis.

Results:

Patients who received apheresis platelet transfusion had a lower 90-day cumulative survival (78.9% vs. 94.2%, P = 0.009), but had no significant difference in overall survival in the Cox model, compared with those without apheresis platelet transfusion. Units of apheresis platelet transfusion (hazard ratio [HR] = 3.103, 95% confidence interval [CI]: 1.720–5.600, P < 0.001) and preoperative platelet count (HR = 0.170, 95% CI: 0.040–0.730, P = 0.017) impacted 90-day survival independently. Multivariate Cox regression analysis also found that units of red blood cell (RBC) transfusion (HR = 1.036, 95% CI: 1.006–1.067, P = 0.018), recipient's age (HR = 1.045, 95% CI: 1.005–1.086, P = 0.025), and ABO blood group comparison (HR = 2.990, 95% CI: 1.341–6.669, P = 0.007) were independent risk factors for overall survival after LDLT.

Conclusions:

This study suggested that apheresis platelets were only associated with early mortality but had no impact on overall survival in LDLT. Units of RBC, recipient's age, and ABO group comparison were independent predictors of long-term outcomes.

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.

Development of a Predictive Model for Blood Transfusions and Bleeding During Liver Transplantation: An Observational Cohort Study

OBJECTIVE

Orthotopic liver transplantation (OLT) frequently is associated with major blood loss and considerable transfusion requirements. The goal of this study was to define the risk factors for multiple transfusions and major bleeding during OLT and to help identify higher risk patients that could benefit from targeted interventions.

DESIGN

OLTs were studied for this observational cohort study.

SETTING

Community hospital.

PARTICIPANTS

A total of 800 consecutive OLTs were studied.

INTERVENTION

No intervention.

MEASUREMENTS AND MAIN RESULTS

Baseline and intraoperative data were gathered. Multivariate logistic regression analyses were performed to find variables associated with 2 outcomes: transfusion of more than 2 units of red blood cells (RBC) and bleeding ≥900 mL. Two nomograms were developed to predict individual risks. The overall intraoperative RBC transfusion was 0.6 ± 1.4 units on average, and 61 surgeries (7.6%) received more than 2 units of RBC (4.5 ± 1.9). Some variables were associated with the outcomes: 5 were associated with transfusion of more than 2 units of RBC (patient's height, starting hemoglobin concentration, starting bilirubin value, the use of a phlebotomy, and central venous pressure [CVP] at the time of vena cava clamping) and 3 with blood loss of ≥900 mL (starting hemoglobin value, Child-Turcotte-Pugh score, and CVP at the time of vena cava clamping). Preclamping CVP showed the strongest association with both outcomes. Nomograms were developed to predict the individual OLT recipients' risk of requiring more than 2 units RBC and suffering from major bleeding. Among the variables associated with multiple RBC transfusions and major bleeding, 3 can lead to interventions: baseline hemoglobin value, the use of a phlebotomy, and the preclamping CVP.

CONCLUSION

Some variables were able to predict the risk of multiple transfusions and major bleeding in this low bleeding liver transplantation population. Further studies based on these variables should be done to better define the role of targeted interventions in higher risk liver transplant recipients.

Transfusion Medicine and Coagulation Management in Organ Transplantation

Organ transplantation recipients present unusual challenges with regard to blood transfusion. Although this patient population requires a larger proportion of blood product resources, liberal transfusion of allogeneic blood products can lead to a plethora of complications. Recent trends suggest that efforts to minimize bleeding, conserve products, and target transfusion to specific deficits and needs are increasingly becoming the standard practice; these must all occur with optimization of graft function and preservation in mind. With newer monitoring modalities and factor concentrates, the approach toward transfusion and bleeding in organ transplantation has rapidly improved in recent years.

Incidence and predictors of massive bleeding in children undergoing liver transplantation: A single-center retrospective analysis

BACKGROUND

Liver transplantation represents a major surgery involving a highly vascular organ. Reports defining the scope of bleeding in pediatric liver transplants are few.

AIMS

We conducted a retrospective analysis of liver transplants performed at our pediatric tertiary care center to quantify blood loss, blood product utilization, and to determine predictors for massive intraoperative bleeding.

METHODS

Pediatric patients who underwent isolated liver transplantation at Boston Children's Hospital between 2011 and 2016 were included. The amount of blood product transfused in the perioperative period and the incidence of postoperative complications were reported. Univariable and multivariable logistic regressions were used to determine predictors for massive bleeding, defined as estimated blood loss exceeding one circulating blood volume within 24 hours.

RESULTS

Sixty-eight children underwent liver transplantation during the study period and were included in the analysis. Multivariable logistic regression analysis identified the following independent predictors of massive bleeding: preoperative hemoglobin level <8.5 g/dL (OR 11.09, 95% CI 1.87-65.76), INR >1.5 (OR 11.62, 95% CI 2.36-57.26), platelet count <100 10⁹ /L (OR 7.92, 95% CI 1.46-43.05), and surgery duration >600 minutes (OR 6.97, 95% CI 0.99-48.92).

CONCLUSIONS

Pediatric liver transplantation is associated with substantial blood loss and a significant blood product transfusion burden. A 43% incidence of massive bleeding is reported. Further efforts are needed to improve bleeding management in this high-risk population.

Survival Predictors in Liver Transplantation: Time-Varying Effect of Red Blood Cell Transfusion

BACKGROUND

Many attempts have been undertaken to better predict outcome after liver transplantation. The aim of this study was to identify the pre- and intraoperative variables that may influence the survival after liver transplantation, at a single institution.

METHODS

Anesthetic records from 543 consecutive patients who underwent liver transplantation from June 2006 to June 2014 were reviewed in this retrospective study. Patients undergoing retransplantation were excluded from the analysis, as were patients with familial amyloid polyneuropathy. Preoperative variables studied were age, sex, Model for End-Stage Liver Disease score, primary diagnosis, cold ischemia time, preoperative international normalized ratio, serum albumin, and and hemoglobin levels. Intraoperative variables included were norepinephrine consumption, blood loss, red blood cell transfusion, and surgical time. Variables significant in the univariate analysis with a P value of <.2 were included in a multivariate Cox regression model.

RESULTS

Only red blood cell transfusion (hazard ratio [HR], 1.16; 95% confidence interval [CI], 1.04-1.29) and female sex (HR, 1.71; 95% CI, 1.10-2.65) were identified as significant independent predictors for survival after liver transplantation. Because of proportionality assumption violation, the multivariate Cox regression model was subsequently upgraded by adding a time-varying interaction between red blood cell transfusion and time since liver transplantation. As a result, we found that at 3 months after liver transplantation, the rate of dying increased 14% (95% CI, 2%-26%) for each unit transfused, and at 6 months it increased 12% (95% CI, 0.3%-24%).

CONCLUSIONS

Red blood cell transfusion ceased to influence survival from 1 year onward.

Transfusion with packed red blood cells while awaiting lung transplantation is associated with reduced survival after lung transplantation

BACKGROUND

The effect of pretransplant transfusion of red blood cells on survival after lung transplantation (LTx) has not been studied.

METHODS

The UNOS database was queried from 2005 to 2013 to compare survival in recipients receiving a transfusion while on the LTx wait list.

RESULTS

Of 12 283 adult patients undergoing single or bilateral LTx from May 2005 onwards, 11 801 met inclusion criteria, among whom 512 required transfusion while on the LTx wait list. Transfusion was associated with a higher mortality hazard in unadjusted Cox proportional hazards analysis (HR=1.296; 95% CI: 1.124, 1.494; P<.001), and in a multivariable Cox model (HR=1.178; 95% CI: 1.013, 1.369; P=.033) after multiple imputation was used to complete data on covariates. Propensity score matching was used to match transfusion recipients to nonrecipients on the likelihood of having received transfusions on the wait list, calculated from characteristics at the time of listing. Unadjusted Cox regression stratified on the matched pairs also demonstrated an association between transfusion receipt on the wait list and higher post-transplant mortality hazard (HR=1.494; 95% CI: 1.127, 1.979; P=.005).

CONCLUSIONS

Blood transfusion while on the LTx wait list was associated with diminished patient survival after transplantation.

Reoperations for Intraabdominal Bleeding Following Deceased Donor Liver Transplantation

Intraabdominal hemorrhage remains one of the most frequent surgical complications after liver transplantation. The aim of the study was to evaluate risk factors for intraabdominal bleeding requiring reoperation and to assess the relevance of the reoperations with respect to short- and long-term outcomes following liver transplantation.

MATERIAL AND METHODS

Data of 603 liver transplantations performed in the Department of General, Transplant and Liver Surgery in the period between January 2011 and September 2014 were analyzed retrospectively. Study end-points comprised: reoperation due to bleeding and death during the first 90 postoperative days and between 90 postoperative day and third post-transplant year.

RESULTS

Reoperations for intraabdominal bleeding were performed after 45 out of 603 (7.5%) transplantations. Low pre-transplant hemoglobin was the only independent predictor of reoperation (p=0.002) with the cut-off of 11.3 g/dl. Postoperative 90-day mortality was significantly higher in patients undergoing reoperation as compared to the remaining patients (15.6% vs 5.6%, p=0.008). Post-transplant survival from 90 days to 3 years was non-significantly lower in patients after reoperation for bleeding (83.3%) as compared to the remaining patients (92.2%, p=0.096). Nevertheless, multivariable analyses did not reveal any significant negative impact of reoperations for bleeding on short-term mortality (p=0.589) and 3-year survival (p=0.079).

CONCLUSIONS

Surgical interventions due to postoperative intraabdominal hemorrhage do not appear to affect short- and long-term outcomes following liver transplantation. Preoperative hemoglobin concentration over 11.3 g/dl is associated with decreased risk of this complication, yet the clinical relevance of this phenomenon is doubtful.

Morbidity and Mortality after High-dose Transfusion

Background

It is well recognized that increased transfusion volumes are associated with increased morbidity and mortality, but dose–response relations between high- and very-high-dose transfusion and clinical outcomes have not been described previously. In this study, the authors assessed (1) the dose–response relation over a wide range of transfusion volumes for morbidity and mortality and (2) other clinical predictors of adverse outcomes.

Methods

The authors retrospectively analyzed electronic medical records for 272,592 medical and surgical patients (excluding those with hematologic malignancies), 3,523 of whom received transfusion (10 or greater erythrocyte units throughout the hospital stay), to create dose–response curves for transfusion volumes and in-hospital morbidity and mortality. Prehospital comorbidities were assessed in a risk-adjusted manner to identify the correlation with clinical outcomes.

Results

For patients receiving high- or very-high-dose transfusion, infections and thrombotic events were four to five times more prevalent than renal, respiratory, and ischemic events. Mortality increased linearly over the entire dose range, with a 10% increase for each 10 units of erythrocytes transfused and 50% mortality after 50 erythrocyte units. Independent predictors of mortality were transfusion dose (odds ratio [OR], 1.037; 95% CI, 1.029 to 1.044), the Charlson comorbidity index (OR, 1.209; 95% CI, 1.141 to 1.276), and a history of congestive heart failure (OR, 1.482; 95% CI, 1.062 to 2.063).

Conclusions

Patients receiving high- or very-high-dose transfusion are at especially high risk for hospital-acquired infections and thrombotic events. Mortality increased linearly over the entire dose range and exceeded 50% after 50 erythrocyte units.

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.

Postreperfusion syndrome during liver transplantation

As surgical and graft preservation techniques have improved and immunosuppressive drugs have advanced, liver transplantation (LT) is now considered the gold standard for treating patients with end-stage liver disease worldwide. However, despite the improved survival following LT, severe hemodynamic disturbances during LT remain a serious issue for the anesthesiologist. The greatest hemodynamic disturbance is postreperfusion syndrome (PRS), which occurs at reperfusion of the donated liver after unclamping of the portal vein. PRS is characterized by marked decreases in mean arterial pressure and systemic vascular resistance, and moderate increases in pulmonary arterial pressure and central venous pressure. The underlying pathophysiological mechanisms of PRS are complex. Moreover, risk factors associated with PRS are not fully understood. Rapid and appropriate treatment with vasopressors, volume replacement, or venesection must be provided depending on the cause of the hemodynamic disturbance when hemodynamic instability becomes profound after reperfusion. The negative effects of PRS on postoperative early morbidity and mortality are clear, but the effect of PRS on postoperative long-term mortality remains a matter of debate.

Acute kidney injury after orthotopic liver transplantation using living donor versus deceased donor grafts: A propensity score-matched analysis

Acute kidney injury (AKI) is a common complication after liver transplantation (LT). Few studies investigating the incidence and risk factors for AKI after living donor liver transplantation (LDLT) have been published. LDLT recipients have a lower risk for post-LT AKI than deceased donor liver transplantation (DDLT) recipients because of higher quality liver grafts. We retrospectively reviewed LDLTs and DDLTs performed at the University of Pittsburgh Medical Center between January 2006 and December 2011. AKI was defined as a 50% increase in serum creatinine (SCr) from baseline (preoperative) values within 48 hours. One hundred LDLT and 424 DDLT recipients were included in the propensity score matching logistic model on the basis of age, sex, Model for End-Stage Liver Disease score, Child-Pugh score, pretransplant SCr, and preexisting diabetes mellitus. Eighty-six pairs were created after 1-to-1 propensity matching. The binary outcome of AKI was analyzed using mixed effects logistic regression, incorporating the main exposure of interest (LDLT versus DDLT) with the aforementioned matching criteria and postreperfusion syndrome, number of units of packed red blood cells, and donor age as fixed effects. In the corresponding matched data set, the incidence of AKI at 72 hours was 23.3% in the LDLT group, significantly lower than the 44.2% in the DDLT group (P = 0.004). Multivariate mixed effects logistic regression showed that living donor liver allografts were significantly associated with reduced odds of AKI at 72 hours after LT (P = 0.047; odds ratio, 0.31; 95% confidence interval, 0.096-0.984). The matched patients had lower body weights, better preserved liver functions, and more stable intraoperative hemodynamic parameters. The donors were also younger for the matched patients than for the unmatched patients. In conclusion, receiving a graft from a living donor has a protective effect against early post-LT AKI.

Splenic artery trunk embolization reduces the surgical risk of liver transplantation

BACKGROUND

Portal hypertension is one of the most important clinical conditions that cause intraoperative intensive hemorrhage in cirrhotic patients undergoing liver transplantation. Pre-transplant portal decompression may reduce the intraoperative bleeding during liver transplantation.

METHODS

Splenic artery trunk embolization (SATE) was performed one month prior to liver transplantation. Platelet count, prealbumin, international normalized ratio, and blood flow in the portal vein and hepatic artery were monitored before and one month after SATE. The measurements above were collected on admission and before surgery in the non-SATE patients, who served as controls. We also recorded the intraoperative blood loss, operating time, required transfusion, post-transplant ascites, and complications within three months after operation in all patients.

RESULTS

SATE significantly reduced portal venous blood flow, increased hepatic arterial blood flow, normalized platelet count, and improved prealbumin and international normalized ratio in the patients before liver transplantation. Compared to the non-SATE patients, the pre-transplant SATE significantly decreased the operating time, intraoperative bleeding, post-transplant ascites and severe surgical complications.

CONCLUSION

Pre-transplant SATE decreases portal pressure, improves liver function reserve, and reduces the surgical risk of liver transplantation effectively in patients with severe portal hypertension.

Acute kidney injury following orthotopic liver transplantation: incidence, risk factors, and effects on patient and graft outcomes

BACKGROUND

Liver transplant recipients frequently develop acute kidney injury (AKI), but the predisposing factors and long-term consequences of AKI are not well understood. The aims of this study were to identify predisposing factors for early post-transplant AKI and the impact of AKI on patient and graft survival and to construct a model to predict AKI using clinical variables.

METHODS

In this 5-year retrospective study, we analysed clinical and laboratory data from 424 liver transplant recipients from our centre.

RESULTS

By 72 h post-transplant, 221 patients (52%) had developed AKI [according to the Kidney Disease Improving Global Outcomes (KDIGO) criteria]. Predisposing factors for development of AKI were female sex, weight (>100 kg), severity of liver disease (Child-Pugh score), pre-existing diabetes mellitus, number of units of blood or fresh frozen plasma transfused during surgery, and non-alcoholic steatohepatitis as the aetiology of end-stage liver disease (P≤0.05). Notably, preoperative serum creatinine (SCr) was not a significant predisposing factor. After fitting a forward stepwise regression model, female sex, weight >100 kg, high Child-Pugh score, and diabetes remained significantly associated with the development of AKI within 72 h (P≤0.05). The area under the receiver operator characteristic curve for the final model was 0.71. The incidence of new chronic kidney disease and requirement for dialysis at 3 months and 1 yr post-transplant were significantly higher among patients who developed AKI.

CONCLUSIONS

Development of AKI within the first 72 h after transplant impacted short-term and long-term graft survival.

Risk Factors Associated with Reoperation for Bleeding following Liver Transplantation

Introduction. This study's objective was to identify risk factors associated with reoperation for bleeding following liver transplantation (LTx). Methods. A retrospective study was performed at a single institution between 2001 and 2012. Operative reports were used to identify patients who underwent reoperation for bleeding within 2 weeks following LTx (operations for nonbleeding etiologies were excluded). Results. Reoperation for bleeding was observed in 101/928 (10.8%) of LTx patients. The following characteristics were associated with reoperation on multivariable analysis: recipient MELD score (OR 1.06/MELD unit, 95% CI 1.03, 1.09), number of platelets transfused (OR 0.73/platelet unit, 95% CI 0.58, 0.91), and aminocaproic acid utilization (OR 0.46, 95% CI 0.27, 0.80). LTx patients who underwent reoperation for bleeding had a longer ICU stay (5 days ± 7 versus 2 days ± 3, P < 0.001) and hospitalization (18 days ± 9 versus 10 days ± 18, P < 0.001). The risk of death increased in patients who underwent reoperation for bleeding (HR 1.89, 95% CI 1.26, 2.85). Conclusion. Reoperation for bleeding following LTx was associated with increased resource utilization and recipient mortality. A lower threshold for intraoperative platelet transfusion and antifibrinolytics, especially in patients with high lab-MELD score, may decrease the incidence of reoperation for bleeding following LTx.

Application of the BAR score as a predictor of short- and long-term survival in liver transplantation patients

BACKGROUND

The balance of risk (BAR) is a prediction system after liver transplantation.

METHODS

To assess the BAR system, a retrospective observational study was performed in 402 patients who had transplant surgery between 1997 and 2012. The BAR score was computed for each patient. Receiver operating characteristic curve analysis with the Hosmer-Lemeshow test was used to calculate sensitivity, specificity, and model calibration. The cutoff value with the best Youden index was selected. Statistical analysis employed the Kaplan-Meier method (log-rank test) for survival, the Mann-Whitney test for group comparison, and multiple logistic regression analysis.

RESULTS

3-month survival was 46% for BAR ≥ 11 and 77% for BAR <11 (p = 0.001); 12-month survival was 44% for BAR ≥ 11 and 69% for BAR <11 (p = 0.001). Factors of survival <3 months were BAR ≥ 11 [odds ratio (OR) 3.08; 95% confidence interval (CI) 1.75-5.42; p = 0.001] and intrasurgical use of packed red blood cells (RBC) above 6 units (OR 4.49; 95% CI 2.73-7.39; p = 0.001). For survival <12 months, factors were BAR ≥ 11 (OR 2.94; 95% CI 1.67-5.16; p = 0.001) and RBC >6 units (OR 2.99; 95% CI 1.92-4.64; p = 0.001).

CONCLUSIONS

Our study contributes to the incorporation of the BAR system into Brazilian transplantation centers.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Prediction of postoperative mortality in liver transplantation in the era of MELD-based liver allocation: a multivariate analysis

BACKGROUND AND AIMS

Liver transplantation is the only curative treatment for end-stage liver disease. While waiting list mortality can be predicted by the MELD-score, reliable scoring systems for the postoperative period do not exist. This study's objective was to identify risk factors that contribute to postoperative mortality.

METHODS

Between December 2006 and March 2011, 429 patients underwent liver transplantation in our department. Risk factors for postoperative mortality in 266 consecutive liver transplantations were identified using univariate and multivariate analyses. Patients who were <18 years, HU-listings, and split-, living related, combined or re-transplantations were excluded from the analysis. The correlation between number of risk factors and mortality was analyzed.

RESULTS

A labMELD ≥20, female sex, coronary heart disease, donor risk index >1.5 and donor Na+>145 mmol/L were identified to be independent predictive factors for postoperative mortality. With increasing number of these risk-factors, postoperative 90-day and 1-year mortality increased (0-1: 0 and 0%; 2: 2.9 and 17.4%; 3: 5.6 and 16.8%; 4: 22.2 and 33.3%; 5-6: 60.9 and 66.2%).

CONCLUSIONS

In this analysis, a simple score was derived that adequately identified patients at risk after liver transplantation. Opening a discussion on the inclusion of these parameters in the process of organ allocation may be a worthwhile venture.

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.

Organ protection in allograft recipients: anesthetic strategies to reduce postoperative morbidity and mortality

PURPOSE OF REVIEW

Organ protection remains a primary objective in the anesthetic management of patients undergoing transplantation. An ongoing effort has been made to develop strategies to improve graft outcome and reduce postoperative morbidity and mortality, but trials have reported conflicting results. The aim of this review was to provide a comprehensive summary of the anesthetic management in transplant recipients and to identify current strategies for organ protection.

RECENT FINDINGS

Decreasing blood products requirements, intraoperative blood glucose control and adequate postoperative pain therapy may improve patient outcome. Vasopressors have been reported to reduce perioperative bleeding but might be associated with postoperative acute renal failure in liver transplantation. Early extubation may increase survival rates in recipients. These perioperative challenges, along with other protective strategies, have been addressed in 20 recently published studies: 10 randomized controlled trials, nine retrospective studies and one prospective study.

SUMMARY

This review identified several promising strategies ensuring organ protection and improving patient outcome after solid organ transplantation. However, as outcomes were difficult to compare, further evidence will be needed before drawing firm conclusions.

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

Background. Significant amounts of red blood cells (RBCs) transfusions are associated with poor outcome after liver transplantation (LT). We report our series of LT without perioperative RBC (P-RBC) transfusions to evaluate its influence on early and long-term outcomes following LT. Methods. A consecutive series of LT between 2006 and 2011 was analyzed. P-RBC transfusion was defined as one or more RBC units administrated during or ≤48 hours after LT. We divided the cohort in “No-Transfusion” and “Yes-Transfusion.” Preoperative status, graft quality, and intra- and postoperative variables were compared to assess P-RBC transfusion risk factors and postoperative outcome. Results. LT was performed in 127 patients (“No-Transfusion” = 39 versus “Yes-Transfusion” = 88). While median MELD was significantly higher in Yes-Transfusion (11 versus 21; P = 0.0001) group, platelet count, prothrombin time, and hemoglobin were significantly lower. On multivariate analysis, the unique independent risk factor associated with P-RBC transfusions was preoperative hemoglobin (P < 0.001). Incidence of postoperative bacterial infections (10 versus 27%; P = 0.03), median ICU (2 versus 3 days; P = 0.03), and hospital stay (7.5 versus 9 days; P = 0.01) were negatively influenced by P-RBC transfusions. However, 30-day mortality (10 versus 15%) and one- (86 versus 70%) and 3-year (77 versus 66%) survival were equivalent in both groups. Conclusions. Recipient MELD score was not a predictive factor for P-RBC transfusion. Patients requiring P-RBC transfusions had worse postoperative outcome. Therefore, maximum efforts must be focused on improving hemoglobin levels during waiting list time to prevent using P-RBC in LT recipients.

Assessment of causes of early death after twenty years of liver transplantation

BACKGROUND

Postoperative poor graft function is a serious complication that can lead to graft loss requiring retransplantation or even death. The postoperative complications of primary nonfunction (PNF), early graft dysfunction (EGD), bleeding due to coagulopathy, and hepatic artery thrombosis (HAT) can lead to graft loss requiring retransplantation or even death. We determined the causes of death after liver transplantation.

METHODS

This was an observational descriptive study on adult liver transplant recipients from September 1991 to December 2011. The cutoff for the definition of death was 30 days after surgery. We included patients older than 18 years of age who underwent liver grafts using the piggyback technique, excluding those who had retransplantations or liver-kidney transplantations.

RESULTS

We analyzed 561 liver transplantations through chart review. After application of exclusion criteria we had 81 patients for analysis. Overall mortality was classified into 3 main causes: PNF (34/81; 42%), EGD (10/81; 12%), and abdominal bleeding due to coagulopathy (9/81; 11%).

CONCLUSION

Despite advances, mortality in the first 30 days after surgery is still high, mainly related to the occurrence of PNF and EGD, whose causality was associated with red blood cell transfusion (>5 U).

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.

Intraoperative cryoprecipitate transfusion and its association with the incidence of biliary complications after liver transplantation--a retrospective cohort study

Background

Cryoprecipitate is largely used for acquired hypofibrinogenemia in the setting of massive hemorrhage in liver transplantation (LT). However, the influence of intraoperative cryoprecipitate transfusion on biliary complications (BC) after LT has not been studied in detail.

Study Design and Methods

In a series of 356 adult patients who received their first LT, the causes of BC were retrospectively studied by multivariate logistic regression analysis. The clinical relationship between intraoperative cryoprecipitate transfusion and BC occurrence was studied through a retrospective cohort study in patients. All patients received follow-ups for one year, and, during the follow-up period, the time of BC occurrence and liver biopsies were recorded.

Results

Intraoperative cryoprecipitate transfusion (RR = 3.46, 95% CI [1.72–6.97], P<0.001), cold ischemia time >8 h (RR = 4.24, 95% CI [2.28–7.92], P<0.01), and high-level Child-Pugh ( RR = 1.71, 95% CI [1.11–2.63], P = 0.014) are independent risk factors to predict BC after LT according to time-to-event analysis. One year BC-free survival probability of patients received intraoperative cryoprecipitate transfusions was significantly lower when compared to the group that received no cryoprecipitate(P<0.001). Moreover, BC patients in the cryoprecipitate transfusion group owned different liver pathological feature, pathological micro-thrombus formation and cholestasis were seen more often (41.4% vs 0%, 62.1% vs 12.5%, respectively) than no cryoprecipitate transfusion group.

Conclusion

These findings suggested that intraoperative cryoprecipitate transfusion was associated with BC after LT. The mechanism of BC occurrence might involve micro-thrombus formation and immune rejection.

Duration of red blood cell storage and outcomes following orthotopic liver transplantation

Liver transplantation may be complicated by massive intraoperative bleeding, and red blood cell (RBC) transfusions may be required. The storage duration or age of transfused RBCs has been shown to affect the morbidity and mortality of critically ill, trauma, and cardiac surgery patients. Here we investigate the effect of RBC age on the outcomes of liver transplant patients. Five hundred thirty-one patients underwent orthotopic liver transplantation between January 1, 2000 and August 15, 2010. The patient demographics, the Model for End-Stage Liver Disease-sodium (MELD-Na) score, and the number and age of RBC units were evaluated with univariate and multivariate models of outcomes, which included mortality rates 2 years after transplantation, postoperative infections, and organ rejection. In a univariate analysis, the number of RBC units (but not the RBC age) was associated with increased 2-year mortality, an increased risk of infection, and a decreased risk of organ rejection. Only the number of RBC units was associated with increased 2-year mortality in a multivariate Cox regression model. The mortality risk was decreased by two-thirds for patients who received <10 U of RBCs versus those who received ≥10 U (hazard ratio = 0.33, 95% confidence interval = 0.16-0.69, P = 0.003). The number of transfused RBC units was not associated with the risk of infection or organ rejection in a multivariate logistic regression model. In conclusion, the RBC age is not associated with infection, organ rejection, or death in liver transplant patients. Patients who receive more blood have an increased risk of death. In a multivariate model, the MELD-Na score was not associated with increased mortality, and this is consistent with previous studies demonstrating that the MELD-Na score is a poor predictor of long-term survival after transplantation.

Blood transfusion utilization and recipient survival at Hospital das Clinicas in São Paulo, Brazil

BACKGROUND

The characteristics of blood recipients including diagnoses associated with transfusion and posttransfusion survival are unreported in Brazil. The goals of this analysis were: 1) to describe blood utilization according to clinical diagnoses and patient characteristics and 2) to determine the factors associated with survival of blood recipients.

STUDY DESIGN AND METHODS

A retrospective cross-sectional analysis was conducted on all inpatients in 2004. Data came from three sources: The first two files consist of data about patient characteristics, clinical diagnosis, and transfusion. Analyses comparing transfused and nontransfused patients were conducted. The third file was used to determine survival recipients up to 3 years after transfusion. Logistic regression was conducted among transfused patients to examine characteristics associated with survival.

RESULTS

In 2004, a total of 30,779 patients were admitted, with 3835 (12.4%) transfused. These patients had 10,479 transfusions episodes, consisting of 39,561 transfused components: 16,748 (42%) red blood cells, 15,828 (40%) platelets (PLTs), and 6190 (16%) plasma. The median number of components transfused was three (range, 1-656) per patient admission. Mortality during hospitalization was different for patients whose admissions included transfusion or not (24% vs. 4%). After 1 year, 56% of transfusion recipients were alive. The multivariable model of factors associated with mortality after transfusion showed that the most significant factors in descending order were hospital ward, increasing age, increasing number of components transfused, and type of components received.

CONCLUSION

Ward and transfusion are markers of underlying medical conditions and are associated with the probability of survival. PLT transfusions are common and likely reflect the types of patients treated. This comprehensive blood utilization study, the first of its kind in Brazil, can help in developing transfusion policy analyses in South America.

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.