Primary liver transplantation without transfusion of red blood cells

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

BACKGROUND

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Bloodless living donor liver transplantation: Risk factors, outcomes, and diagnostic predictors

Massive bleeding is often unavoidable during liver transplantation (LT). However, blood transfusions are associated with risks and should be avoided whenever possible. This study compares preoperative factors and outcomes between non-transfusion and transfusion groups to identify variables that could be used to predict bloodless surgery in living donor liver transplantation (LDLT) patients.We conducted a retrospective study of 87 LDLT patients. The group of patients who did not require packed red blood cell (PRBC) transfusion (non-PRBC group, n = 44) was compared with those who did (PRBC group, n = 43). We compared risk factors, fluid management, and outcomes between the groups and identified variables for prediction of transfusion during LDLT.Compared with the PRBC group, the non-PRBC group had a lower model for end-stage liver disease (MELD) score (8.1 ± 1.1 vs 18.2 ± 8.8), international normalized ratio (INR) (1.16 ± 0.1 vs 1.80 ± 0.94), and partial thromboplastin time (PTT) (37.1 ± 6.3 vs 54.1 ± 24.0), but higher hemoglobin (Hb) (13.6 ± 1.6 vs 11.5 ± 2.2) and hematocrit (HCT) (39.1 ± 4.4 vs 32.6 ± 6.0). The non-PRBC group were more likely to receive colloid and albumin but had shorter intensive care unit (ICU) and hospital length of stay. The area under the receiver operative characteristic (ROC) curve of the MELD score was the highest (91%) using a cutoff value of 10.5.Patients without PRBC transfusion during LDLT were in better condition preoperatively and had better outcomes. The MELD score is a significant predictor for PRBC transfusion.

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

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

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.

Massive haemorrhage in liver transplantation: Consequences, prediction and management

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

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.

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.

Perioperative risk factors for pulmonary complications after liver transplantation

Using monofactorial and multivariate logistic regression analyses, the correlation of perioperative risk factors with postoperative pulmonary complications (PPCs) within 1 month after orthotopic liver transplantation (OLT) was investigated. Data on 107 patients (median age 46.8 years, 72% male) with end-stage liver disease who received OLT were retrospectively analysed. The incidence of PPCs was 60.7%. Overall mortality was 13.1% and pulmonary causes accounted for 85.7% of deaths. Mortality was 18.5% and 4.8% for patients with and without pulmonary complications, respectively. Independent risk factors for PPCs were a preoperative model for end-stage liver disease (MELD) score > or =25, intraoperative fluid transfusion volume > 10 1 and intraoperative blood transfusion volume > 4 l. A fluid balance of < or = -300 ml for > or =2 days of the first 3 days after surgery was protective. Other variables studied did not predict PPCs. It was concluded that improving the patient's preoperative medical condition, restricting intraoperative transfusion volumes and maintaining a negative fluid balance in the first 3 days after operation may decrease PPCs.

[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.

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.

Platelet transfusion during liver transplantation is associated with increased postoperative mortality due to acute lung injury

BACKGROUND

Platelet transfusions have been identified as an independent risk factor for survival after orthotopic liver transplantation (OLT). In this study, we analyzed the specific causes of mortality and graft loss in relation to platelet transfusions during OLT.

METHODS

In a series of 449 consecutive adult patients undergoing a first OLT, the causes of patient death and graft failure were studied in patients who did or did not receive perioperative platelet transfusions.

RESULTS

Patient and graft survival were significantly reduced in patients who received platelet transfusions, compared with those who did not (74% vs 92%, and 69% vs 85%, respectively at 1 yr; P < 0.001). Lower survival rates in patients who received platelets were attributed to a significantly higher rate of early mortality because of acute lung injury (4.4% vs 0.4%; P = 0.004). There were no significant differences in other causes of mortality between the two groups. The main cause of graft loss in patients receiving platelets was patient death with a functioning graft.

CONCLUSIONS

These findings suggest that platelet transfusions are an important risk factor for mortality after OLT. The current study extends previous observations by identifying acute lung injury as the main determinant of increased mortality. The higher rate of graft loss in patients receiving platelets is related to the higher overall mortality rate and does not result from specific adverse effects of transfused platelets on the grafted liver.

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.

The impact of intraoperative transfusion of platelets and red blood cells on survival after liver transplantation

BACKGROUND

Intraoperative transfusion of red blood cells (RBC) is associated with adverse outcome after orthotopic liver transplantation (OLT). Although experimental studies have shown that platelets contribute to reperfusion injury of the liver, the influence of allogeneic platelet transfusion on outcome has not been studied in detail. In this study, we evaluate the impact of various blood products on outcome after OLT.

METHODS

Twenty-nine variables, including blood product transfusions, were studied in relation to outcome in 433 adult patients undergoing a first OLT between 1989 and 2004. Data were analyzed using uni- and multivariate stepwise Cox's proportional hazards analyses, as well as propensity score-adjusted analyses for platelet transfusion to control for selection bias in the use of blood products.

RESULTS

The proportion of patients receiving transfusion of any blood component decreased from 100% in the period 1989-1996 to 74% in the period 1997-2004. In uni- and multivariate analyses, the indication for transplantation, transfusion of platelets and RBC were highly dominant in predicting 1-yr patient survival. These risk factors were independent from well-accepted indices of disease, such as the Model for End-Stage Liver Disease score and Karnofsky score. The effect on 1-yr survival was dose-related with a hazard ratio of 1.377 per unit of platelets (P = 0.01) and 1.057 per unit of RBC (P = 0.001). The negative impact of platelet transfusion on survival was confirmed by propensity-adjusted analysis.

CONCLUSION

This retrospective study indicates that, in addition to RBC, platelet transfusions are an independent risk factor for survival after OLT. These findings have important implications for transfusion practice in liver transplant recipients.

Intraoperative massive transfusion decreases survival after liver transplantation

Patients undergoing liver transplantation often experience coagulopathy and massive intraoperative blood loss that can lead to morbidity and reduced survival. The aim of this study was to verify the survival rate and discover predictive factors for death among liver transplant patients who received massive intraoperative blood transfusions. This cohort study was based on prospective data collected retrospectively from January 2004 to July 2006. The 232 patients were distributed according to their blood requirements, (namely, more or less than 6 units), including red blood cell saver. The statistical analyses were performed using Student t test, Cox hazard regression, and the Kaplan-Meier method (log-rank test). The massively transfused cohort displayed higher Child-Pugh classifications (10.2 vs 9.6; P = .03); model for end-stage liver disease (MELD) scores (19 vs 17; P = .02); recipient weights (75.4 vs 71 kg; P = .03); as well as warm ischemia times (70.7 vs 56.4 minutes; P < .001) and surgery times (584.6 vs 503.4 minutes; P < .05). The proportional hazard (Cox) regression analysis showed that the risk of death increased 2.1% for each unit of donor sodium and 1.6% for each additional year of donors age over 50. The survival rates at 6, 12, 60, and 120 months for > or = 6 vs <6 U of blood transfusion of 63.8% vs 83.3%; 53.9% vs 76.3%; 40% vs 60%; 34.5% vs 49.2%. In conclusion, we observed that patients receiving over 6 red blood cell units intraoperatively displayed reduced survival. Predictive factors for this risk factor were high donor level of sodium and of age.

Fungal infections in solid organ transplantation

Renal, liver, heart and lung transplantation are now considered to be the standard therapeutic interventions in patients with end-stage organ failure. Infectious complications following transplantation are relatively common due to the transplant recipients overall immunosuppressed status. The incidence of invasive mycoses following solid organ transplant ranges from 5 to 42% depending on the organ transplanted. These mycoses are associated with high overall mortality rates. Candida and Aspergillus spp. produce most of these infections. This article will review the risk factors, clinical presentation and treatment of invasive fungal infections in solid organ transplant patients, and evaluate the role of prophylactic therapy in this group of patients.

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

Massive blood transfusion (MBT) remains a serious and common occurrence in liver transplantation surgery. This retrospective cohort study was undertaken to identify preoperative predictors of MBT and to develop a risk index for MBT in liver transplantation. Data were retrospectively collected on all liver transplantations carried out at a single institution between January 1998 and March 2004. Multivariable logistic regression analysis was used to identify independent predictor variables of MBT, defined as >/=6 units of red blood cell concentrate (RBC) in the first 24 hours of surgery. The model was internally validated by bootstrapping. Of the 460 liver transplant recipients, 193 (42%) received >/=6 units of RBC within 24 hours of surgery. Unadjusted analyses identified 12 preoperative predictors of MBT: age, height, gender, repeat transplantation, etiology of liver failure, and preoperative laboratory values (hemoglobin concentration, platelet count, international normalized ratio for prothrombin activity [INR], albumin, total bilirubin, and creatinine). In multivariable logistic regression, 7 independent predictors of MBT were identified: age (>40 years), hemoglobin concentration (</=10.0 g/dL), INR (1.2-1.99, and >2.0), platelet count (</=70 x 10(9)/L), creatinine (>/=110 micromol/L for female subjects and >/=120 micromol/L for male subjects), albumin (< 28 g/L), and repeat transplantation. The area under the receiver-operating characteristic curve (ROC) for the model was 0.82. By using the regression beta coefficients to derive weights for each of these predictors, a risk index was developed that assigned each patient a score between 0 and 8. The ROC for this risk index was 0.79. MBT in liver transplantation surgery can be accurately predicted by 7 readily available preoperative predictors.

Avoiding blood products during liver transplantation

Liver transplantation is a major surgical procedure usually requiring large amount of blood products (red cells, platelets, fresh-frozen plasma). We developed a multidisciplinary transfusion-free protocol for liver transplantation in Jehovah's witnesses who refuse the use of blood products but accept organ transplantation. Between September 1998 and November 2004, 9 of 29 Jehovah's witnesses evaluated for liver transplantation were transplanted after medical preparation. None of these patients received any blood product during the surgical procedure. This experience may be beneficial for the entire liver transplantation population, as excessive transfusion has been linked to increased morbidity and mortality in liver transplantation.

Red blood cell transfusion in liver transplantation: a case-control study

INTRODUCTION

We aimed to analyze the influence of intraoperative blood transfusion on postoperative complications and survival and to identify the preoperative variables associated with greater intraoperative bleeding.

MATERIALS AND METHODS

Thirty-one elective liver transplantations (OLT) without blood transfusion performed between 1986 and 2002 (group 1) were compared with 62 patients (group 2) who underwent elective OLT with intraoperative transfusion after matching for gender, disease severity, and chronology.

RESULTS

The hemoglobin and hematocrit values were significantly greater in group 1 compared to group 2. No significant differences were reported for the other parameters. In particular, the type of surgical technique had no influence on the blood requirement. As expected the nontransfused patients received less autologous packed red blood cells compared with the transfused patients. No differences were observed in either group for mean CIT, ICU and hospital stay, or acute rejection. A significant difference was observed in the number of postoperative infectious episodes, which was higher in group 2 (28 vs 5, P = .01). Graft and patient survivals at 3 months and 5 years did not differ significantly between groups.

CONCLUSIONS

OLT without blood transfusion may be achieved in the presence of good recipient conditions. Lower preoperative hemoglobin and hematocrit values were associated with greater intraoperative transfusions.

Liver transplantation in Jehovah's witnesses

For religious reasons, Jehovah's witnesses refuse transfusion of blood products (red cells, platelets, plasma), but may accept organ transplantation. The authors developed a multidisciplinary protocol for liver transplantation in Jehovah's witnesses. In a 6-year period, nine Jehovah's witness patients were listed for liver transplantation. They received preoperative erythropoietin therapy, with iron and folic acid that allowed significant haematocrit increase. Two patients underwent partial spleen embolization to increase platelet count. Seven patients underwent cadaveric whole liver transplantation, and two right lobe living-related liver transplantation, using continuous circuit cell saving system and high dose aprotinin. No patient received any blood product during the surgical procedure. One patient suffering from deep anaemia after living-related liver transplantation was transfused as required by his family, but died from aspergillus infection. One 6-year-old child was transfused against her parent's will. The authors demonstrated that it is possible to increase haematocrit and platelet levels in cirrhotic patients awaiting liver transplantation. They were able to reduce intraoperative need for blood products, allowing liver transplantation in prepared Jehovah's witness patients. This experience may be beneficial for non-Jehovah's witness liver transplant recipients.

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

The use of living donation is an important option for patients in need of liver transplant. We retrospectively reviewed the preoperative Model for End-Stage Liver Disease (MELD) score, baseline coagulation laboratory results, and intraoperative transfusion of red blood cells and component therapy for 27 living donation transplants and 69 cadaveric donation transplants during a 3-yr period (2001-2004). Patients undergoing living donation transplantation had significantly lower MELD scores and preserved coagulation function compared with cadaveric donation transplantation recipients (P < 0.001). The living donation transplant patients also received significantly fewer transfusions of red blood cells and component therapy compared with the cadaveric donation transplant patients (P < 0.001). For the combined population of both cadaveric donation transplant and living donation transplant patients, there were significant associations between MELD score and preoperative coagulation tests (P < 0.001) and intraoperative transfusion of blood and component therapy. MELD score and preoperative fibrinogen concentration were identified as independent predictors of transfusion exposure. In conclusion, we detected significant differences in severity of disease at time of transplantation, degree of impairment of coagulation function, and need for transfusion of red blood cells and component therapy between patients undergoing living donation transplantation compared with patients undergoing cadaveric donation transplantation.

Single pretransplant bolus of recombinant activated factor VII ameliorates influence of risk factors for blood loss during orthotopic liver transplantation

Large blood loss and transfusions during liver transplantation (LTx) may lead to serious complications and have a negative impact on post-transplant mortality and morbidity. In the retrospective study we compared two groups of recipients of primary cadaveric liver transplantation: group I (study group), consisted of 28 patients with preoperative risk of high intraoperative blood loss, including severe uncorrected coagulopathy. This group was given a bolus of recombinant activated factor VII (rFVIIa) just before LTx. Group II (control group) included 61 patients without a particular risk for increased intraoperative blood loss. These patients were not given rFVIIa. We analyzed both groups for: coagulation parameters before, during and after surgery (INR, APTT, factor VII activity), blood and FFP transfusions, operative time, postoperative complications (vascular thrombosis, reoperation for bleeding), postoperative ICU stay, post-transplant hospitalization time and mortality. Patients from the study group (I) had significantly worse coagulation parameters than patients in the control group (II) at the start of the surgical procedure; however, after administration of a bolus of rFVIIa there was immediate correction of coagulation in all recipients. No significant differences in intraoperative blood transfusions were observed between study and control groups (1980 +/- 311.4 mL vs. 1527 +/- 154.2 mL, respectively), operating time (8.7 h vs. 8.9 h) or ICU and hospital stay (7.03 days vs. 6.15 days and 40.89 days vs. 41.1 days). Re-exploration because of bleeding was performed in three patients from group I (10.7%) and in seven patients (11.5%) from group II. No single case of vascular thrombosis was observed in the study group, while in the control group there were three hepatic artery thromboses, two portal vein thromboses and one hepatic vein thrombosis. We conclude that rFVIIa given preoperatively to liver transplant recipients with several risk factors for high intraoperative bleeding adjusts these patients to a normal risk group, without an increased risk for thrombotic complications.

Dextrose in the banked blood products does not seem to affect the blood glucose levels in patients undergoing liver transplantation

AIM: Hyperglycemia commonly seen in liver transplantation (LT) has often been attributed to the dextrose in the storage solution of blood transfusion products. The purpose of the study is to compare the changes of the blood glucose levels in transfused and non-transfused patients during LT.

METHODS: A retrospective study on 60 biliary pediatric patients and 16 adult patients undergoing LT was carried out. Transfused pediatric patients were included in Group I (GI), those not transfused in Group II (GII). Twelve adult patients were not given transfusion and assigned to Group III (GIII); whereas, four adult patients who received massive transfusion were assigned to Group IV (GIV). The blood glucose levels, volume of blood transfused, and the volume of crystalloid infused were recorded, compared and analyzed.

RESULTS: Results showed that the changes in blood glucose levels during LT for both non-transfused and minimally transfused pediatric groups and non-transfused and massively-transfused adult groups were almost the same.

CONCLUSION: We conclude that blood transfusion does not cause significant changes in the blood glucose levels in this study.

Transfusion predictors in liver transplant

In this study we sought to determine the factors influencing red blood cell (RBC) transfusions and to study the transfusion practice of anesthesiologists during liver transplants. A retrospective study of 206 successive liver transplants was undertaken during a period of 52 mo. Transfused blood products were identified. Twenty variables were analyzed in a univariate fashion. For the multivariate analysis, the cases were divided in 2 subgroups: more than 4 RBC units transfused and 4 or less RBC units transfused. The average number of RBC units transfused during a liver transplant was 2.8 (+/- 3.5) per patient, 32.0% did not receive any RBC, and 19.4% did not receive any blood products during the transplant. Three variables were related to the number of RBC units transfused: the starting International Normalized Ratio value, the starting platelet count, and the duration of surgery. We found that there was a wide difference in the transfusion practice of the anesthesiologists involved in this series of liver transplants. It was difficult to identify predictive factors for RBC transfusions when the transfusion rate was small and because of the variability in human factors. Plasma transfusion did not decrease the rate of RBC transfusions; sometimes it was the contrary.

IMPLICATIONS

This is a retrospective study of 206 liver transplants over 52 mo to identify the predictive factors of red blood cell transfusions and the anesthesiologists' transfusion strategies. We conclude that there is a wide difference in transfusion practices among anesthesiologists.

Intraoperative red blood cell transfusion in liver transplantation: influence on patient outcome, prediction of requirements, and measures to reduce them

Objectives of this study are to quantify the need for blood transfusion during liver transplantation (LT) and confirm the importance of intraoperative blood transfusion as an independent prognostic factor for postoperative outcome. Furthermore, we try to detect useful variables for the preoperative identification of patients likely to require transfusion of packed red blood cell units (PRCUs) and identify measures to reduce transfusion needs. Data were collected prospectively between September 1998 and November 2000. One hundred twenty-two LTs were included in the study. Forty-two patients (34%) did not require transfusion of PRCUs. In multivariate analysis, transfusion of more than three PRCUs was found to be the only significant variable associated with prolonged hospital stay. In addition, excluding perioperative deaths, PRCU transfusion, using a cutoff value of six units, was the only variable to reach statistical significance (P =.008; risk ratio, 4.93; 95% confidence interval, 15 to 15.9) to predict survival in a multivariate analysis that also included Child's class and United Network for Organ Sharing (UNOS) classification. Moreover, only preoperative hemoglobin (Hb) level was found to significantly predict the need for transfusion of one or more PCRUs. Finally, only UNOS classification and placement of an intraoperative portacaval shunt were found to be statistically significant to predict the need to transfuse more than six PRCUs. We found the requirement of even a moderate number of blood transfusions is associated with longer hospital stay, and transfusion of more than six PRCUs is associated with diminished survival. Preoperative normalization of Hb levels and placement of an intraoperative portacaval shunt can diminish the number of blood transfusions during LT.

Changes in the spectrum and risk factors for invasive candidiasis in liver transplant recipients: prospective, multicenter, case-controlled study

BACKGROUND

This study determines whether the spectrum, risk factors, and outcome of invasive candidiasis in liver transplant recipients have changed.

METHODS

Thirty-five consecutive liver transplant recipients with invasive candidiasis were prospectively studied in a case-controlled, multicenter study. One control was matched with the case for duration of hospitalization and the other for antibiotic use so that risk factors unique in liver transplantation could be elicited.

RESULTS

In matched-pair analysis, antibiotic prophylaxis for spontaneous bacterial peritonitis (odds ratio [OR] 8.3, P=0.002), posttransplant dialysis (OR 7.6, P=0.0009), and retransplantation (OR 16.4, P=0.0018) were independently significant predictors of invasive candidiasis. Candida spp. included C. albicans in 65% of patients, C. glabrata in 21%, C. tropicalis in 9%, C. parapsilosis in 3%, and C. guilliermondii in 3%. Patients with C. albicans infections were less likely to have received antifungal prophylaxis than those with non-albicans Candida infections (13.6% vs. 50%, P=0.04). The mortality rate was 36.1% for the cases and 2.8% for the controls (OR 25.0, 95% confidence interval, 6.2-100.5, P=0.0002). Non-albicans Candida infections (P=0.04) and prior antifungal prophylaxis (P=0.05) correlated with poorer outcome in the cases.

CONCLUSIONS

Our study has identified predictors for Candida infections in the current era that have implications relevant for targeting the prophylaxis toward the high-risk patients. Routine use of antifungal prophylaxis warrants concern given the emergence of non-albicans Candida spp. as significant pathogens after liver transplantation and higher mortality in patients with these infections.

Liver failure, transplantation, and critical care

The management of patients for end-stage liver disease in the ICU mandates a multidisciplinary approach and intense monitoring. Orthotopic liver transplantation still remains the only definitive therapy. Given the increasing disparity between the number of potential recipients and available cadaver organs, the current challenge is to optimize outcome with the limited resource. In recent years, considerable progress has been made in developing specific and supportive medical measures. Future research should target a better understanding of mechanisms responsible for liver cell death and liver regeneration, as well as developments in xenotransplantation, hepatocyte transplantation, and liver-directed gene therapy.

Fungal infections in the recipients of solid organ transplantation

The advent of effective antibacterial and antiviral prophylatic and therapeutic strategies has led to the emergence of opportunistic mycoses as a principal cause of infection-related mortality in organ transplant recipients. Candida and Aspergillus species have accounted for most invasive fungal infections in organ transplant recipients. Epidemiologic trends within the last decade, however, are notable for the emergence of mycelial fungi other than Aspergillus as increasingly important pathogens in these patients. This article reviews the epidemiology, clinical manifestations, pathogenetic basis, diagnosis, and management of invasive fungal infections after organ transplantation in context of emerging trends and new developments in these areas.

Trends in invasive fungal infections in liver transplant recipients: correlation with evolution in transplantation practices

BACKGROUND

The incidence of invasive fungal infections, particularly invasive candidiasis, after liver transplantation is strongly influenced by surgical factors and technical complexity of the surgery. We assessed the temporal trends in invasive fungal infections in the context of evolution in liver transplantation practices, technical developments, and other risk factors.

METHODS

Demographic and clinical characteristics of the patients, transplantation-related variables, and rates of infection were longitudinally analyzed over the last 10 years in 190 consecutive liver transplant recipients at our institution. Trends for categorical data were evaluated using the Cochran-Armitage trend test and for continuous variables using analysis of variance with linear contrast.

RESULTS

A decrease in the length of operation (P=0.03), intraoperative transfusion requirements (P=0.0001), cold ischemic time (P<0.0001), use of roux-en-Y biliary anastomosis (P=0.0015), rate of biopsy proven rejection (P<0.0001), and retransplantation (P=0.056) was documented over the successive years. A significant decline in Child-Pugh score (P=0.02) and in the proportion of patients transplanted as UNOS 2a occurred (P=0.0001). Although the incidence of cytomegalovirus infection remained unchanged, a significant increase in the frequency of primary cytomegalovirus infection (P=0.045), and a decrease in cytomegalovirus disease (P=0.0006) was documented. Over the same time period, a significant decrease in the incidence of invasive candidiasis (P=0.015), and an insignificant increase in the rate of invasive aspergillosis (P=0.20) occurred.

CONCLUSION

Notable technical developments in liver transplantation practices and risk profiles of patients have occurred over the decade. These variables may have a role in influencing the evolving trends in invasive fungal infections in liver transplant recipients.

Trends in the epidemiology of opportunistic fungal infections: predisposing factors and the impact of antimicrobial use practices

In the past decade, the frequency of opportunistic fungal infections has increased, and the spectrum of fungal pathogens has changed. The increasing number of susceptible hosts, the introduction of newer modalities for hematopoietic stem cell transplantation, the evolution of organ transplantation practices, the use of novel immunosuppressive agents, and current antimicrobial prophylactic strategies have likely contributed to the changing epidemiology of invasive mycoses. The introduction of azoles more than a decade ago has had a profound impact on curtailing candidal infections. However, a dramatic increase in azole-resistant Candida species and mold infections has been documented. The trends in time of onset, spectrum, and frequency of infections due to invasive molds and opportunistic yeasts are unique for different fungi and vary between subsets of immunocompromised hosts. This review discusses the implications of these trends for guiding judicious use of antimicrobial prophylactics and for unraveling the pathophysiological basis of fungal infections.

Temporary portocaval shunt during liver transplantation with vena cava preservation. Results of a prospective randomized study

This study aims to determine whether the use of a temporary portocaval shunt (PCS) improves hemodynamic and metabolic evolution during orthotopic liver transplantation (OLT). Preservation of the vena cava during OLT has gained wide acceptance. However, benefits of adding a temporary PCS to the piggyback technique during the anhepatic phase in patients with cirrhosis have not been shown. Eighty patients with cirrhosis were studied prospectively. They were randomly distributed into two groups: patients with a temporary PCS (n = 40) and those without a PCS (n = 40). In all cases, the piggyback technique was used. Hemodynamic profiles and biochemical data during OLT and clinical evolution after OLT were evaluated. Preoperative data were similar in both groups. Surgical time also was similar (403 +/- 77 v 387 +/- 56 minutes; P = .3). Red blood cell requirements were lower in the PCS group (2.3 +/- 2.5 v 3.3 +/- 2.9 units), although differences were not significant. In the PCS group, 45% of patients did not need red blood cell transfusion, whereas in the other group, only 22% were not administered a transfusion (P = .03). During the anhepatic phase, the decrease in cardiac output was lower in the PCS group (-9.6% v -19%; P = .05), whereas diuresis during the anhepatic phase was greater in the PCS group (3.6 +/- 2.97 v 2.1 +/- 1.38 mL/kg/h; P = .005). There were no differences in liver biochemical parameters during the first 3 postoperative days. Nevertheless, creatinine levels increased significantly during this period only in the no-PCS group. The use of a temporary PCS during OLT improves hemodynamic status, reduces intraoperative transfusion requirements, and preserves renal function during and after OLT.

Liver transplantation: current status and novel approaches to liver replacement

The major challenge currently facing liver transplantation is the performance of a greater number of liver transplants, which has been fueled by the large and growing disparity between the increasing number of qualified patients listed for transplantation and the relatively static number of available cadaver donor organs. In the past 2 years, approximately 4500 liver transplants have been performed annually, with 1-year survival rates in the 85%-90% range, while the waiting list has expanded as of November 2000 to more than 16,000 patients, resulting in an increasing death rate among listed patients. In the short term, there will continue to be a major focus on more effective use of available cadaver donor organs to balance the competing principles of justice (patients with most urgent need for transplant and lower probability of posttransplant survival) and medical utility (patients with less urgent need for transplant and higher odds of postoperative survival). Over the long term, there will be an increasing application of novel approaches to liver replacement including cadaver split liver transplantation and adult living donor liver transplantation and possibly, in the more distant future, xenotransplantation and hepatocyte transplantation. The treatment, and ideally the prevention, of recurrent disease after liver transplantation, particularly chronic hepatitis C-the most common indication for transplantation-is a major priority to optimize the use of liver grafts. Finally, improved immunosuppressive strategies, including movement toward minimal immunosuppression and steroid withdrawal and the development of safer and more effective drugs, is another important factor that has the potential to increase the success of liver transplantation.

Liver transplantation at the millennium. Past, present, and future

During the past 3 decades, liver transplantation has achieved such acceptance that more than 12,000 qualified recipients are listed for liver transplantation in the United States, but unfortunately just over 4000 cadaver donor organs are available each year. Thus, given the increasing disparity between the number of potential recipients and available cadaver organs, the current challenge in liver transplantation is to optimize the outcome of liver transplantation from this limited resource. Currently under way is re-evaluation of selection criteria to use these 4000 cadaver liver grafts most effectively by striking the proper balance between medical urgency and utility. In parallel with this re-evaluation, there is ongoing expansion of cadaver split-liver transplantation and adult living related and unrelated liver transplantation. Hoped-for but as yet unachieved developments in liver transplantation are xenotransplantation, hepatocyte transplantation, and liver-directed gene therapy. Liver transplantation has come a long way from the initial, unsuccessful human transplantations in 1963, but many challenges remain.