Evaluation of cell salvage autotransfusion utility during liver transplantation

Efficacy of intraoperative blood salvage and autotransfusion in living-donor liver transplantation: a retrospective cohort study

BACKGROUND

Liver transplantation (LT) may be associated with massive blood loss and the need for allogeneic blood transfusion. Intraoperative blood salvage autotransfusion (IBSA) can reduce the need for allogeneic blood transfusion. This study aimed to investigate the effectiveness of blood salvage in LT.

METHODS

Among 355 adult patients who underwent elective living-donor LT between January 1, 2019, and December 31, 2022, 59 recipients without advanced hepatocellular carcinoma received IBSA using Cell Saver (CS group). Based on sex, age, model for end-stage liver disease (MELD) score, preoperative laboratory results, and other factors, 118 of the 296 recipients who did not undergo IBSA were matched using propensity score (non-CS group). The primary outcome was the amount of intraoperative allogenic red blood cell (RBC) transfusion. Comparisons were made between the two groups regarding the amount of other blood components transfused and postoperative laboratory findings.

RESULTS

The transfused allogeneic RBC for the CS group was significantly lower than that of the non-CS group (1,506.0 vs. 1,957.5 ml, P = 0.026). No significant differences in the transfused total fresh frozen plasma, platelets, cryoprecipitate, and estimated blood loss were observed between the two groups. The postoperative allogeneic RBC transfusion was significantly lower in the CS group than in the non-CS group (1,500.0 vs. 2,100.0 ml, P = 0.039). No significant differences in postoperative laboratory findings were observed at postoperative day 1 and discharge.

CONCLUSIONS

Using IBSA during LT can effectively reduce the need for perioperative allogeneic blood transfusions without causing subsequent coagulopathy.

Patient Blood Management in Liver Transplant—A Concise Review

Transfusion of blood products in orthotopic liver transplantation (OLT) significantly increases post-transplant morbidity and mortality and is associated with reduced graft survival. Based on these results, an active effort to prevent and minimize blood transfusion is required. Patient blood management is a revolutionary approach defined as a patient-centered, systematic, evidence-based approach to improve patient outcomes by managing and preserving a patient’s own blood while promoting patient safety and empowerment. This approach is based on three pillars of treatment: (1) detecting and correcting anemia and thrombocytopenia, (2) minimizing iatrogenic blood loss, detecting, and correcting coagulopathy, and (3) harnessing and increasing anemia tolerance. This review emphasizes the importance of the three-pillar nine-field matrix of patient blood management to improve patient outcomes in liver transplant recipients.

Should Cell Salvage Be Used in Liver Resection and Transplantation? A Systematic Review and Meta-analysis

OBJECTIVE

To evaluate the effect of intraoperative blood cell salvage and autotransfusion (IBSA) use on red blood cell (RBC) transfusion and postoperative outcomes in liver surgery.

BACKGROUND

Intraoperative RBC transfusions are common in liver surgery and associated with increased morbidity. IBSA can be utilized to minimize allogeneic transfusion. A theoretical risk of cancer dissemination has limited IBSA adoption in oncologic surgery.

METHODS

Electronic databases were searched from inception until May 2021. All studies comparing IBSA use with control in liver surgery were included. Screening, data extraction, and risk of bias assessment were conducted independently, in duplicate. The primary outcome was intraoperative allogeneic RBC transfusion (proportion of patients and volume of blood transfused). Core secondary outcomes included: overall survival and disease-free survival, transfusion-related complications, length of hospital stay, and hospitalization costs. Data from transplant and resection studies were analyzed separately. Random effects models were used for meta-analysis.

RESULTS

Twenty-one observational studies were included (16 transplant, 5 resection, n=3433 patients). Seventeen studies incorporated oncologic indications. In transplant, IBSA was associated with decreased allogeneic RBC transfusion [mean difference -1.81, 95% confidence interval (-3.22, -0.40), P =0.01, I 2 =86%, very-low certainty]. Few resection studies reported on transfusion for meta-analysis. No significant difference existed in overall survival or disease-free survival in liver transplant [hazard ratio (HR)=1.12 (0.75, 1.68), P =0.59, I 2 =0%; HR=0.93 (0.57, 1.48), P =0.75, I 2 =0%] and liver resection [HR=0.69 (0.45, 1.05), P =0.08, I 2 =0%; HR=0.93 (0.59, 1.45), P =0.74, I 2 =0%].

CONCLUSION

IBSA may reduce intraoperative allogeneic RBC transfusion without compromising oncologic outcomes. The current evidence base is limited in size and quality, and high-quality randomized controlled trials are needed.

Viscoelastic Management of Coagulopathy during the Perioperative Period of Liver Transplantation

Viscoelastic testing (VET) in liver transplantation (LT) has been used since its origin, in combination with standard laboratory testing (SLT). There are only a few, small, randomized controlled trials that demonstrated a reduction in transfusion rates using VET to guide coagulation management. Retrospective analyses contrasting VET to SLT have demonstrated mixed results, with a recent concern for overtreatment and the increase in postoperative thrombotic events. An oversight of many studies evaluating VET in LT is a single protocol that does not address the different phases of surgery, in addition to pre- and postoperative management. Furthermore, the coagulation spectrum of patients entering and exiting the operating room is diverse, as these patients can have varying anatomic and physiologic risk factors for thrombosis. A single transfusion strategy for all is short sighted. VET in combination with SLT creates the opportunity for personalized resuscitation in surgery which can address the many challenges in LT where patients are at a paradoxical risk for both life-threatening bleeding and clotting. With emerging data on the role of rebalanced coagulation in cirrhosis and hypercoagulability following LT, there are numerous potential roles in VET management of LT that have been unaddressed.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Clinical prognosis of intraoperative blood salvage autotransfusion in liver transplantation for hepatocellular carcinoma: A systematic review and meta-analysis

Background

Intraoperative blood salvage autotransfusion(IBSA) has been widely used in a variety of surgeries, but the use of IBSA in hepatocellular carcinoma (HCC) patients undergoing liver transplantation (LT) is controversial. Numerous studies have reported that IBSA used during LT for HCC is not associated with adverse oncologic outcomes. This systematic review and meta-analysis aims to estimate the clinical prognosis of IBSA for patients with H+CC undergoing LT.

Methods

MEDLINE, Embase, Web of Science, and Cochrane Library were searched for articles describing IBSA in HCC patients undergoing LT from the date of inception until May 1, 2022, and a meta-analysis was performed. Study heterogeneity was assessed by I² test. Publication bias was evaluated by funnel plots, Egger’s and Begg’s test.

Results

12 studies enrolling a total of 2253 cases (1374 IBSA and 879 non-IBSA cases) are included in this meta-analysis. The recurrence rate(RR) at 5-year(OR=0.75; 95%CI, 0.59-0.95; P=0.02) and 7-year(OR=0.65; 95%CI, 0.55-0.97; P=0.03) in the IBSA group is slightly lower than non-IBSA group. There are no significant differences in the 1-year RR(OR=0.77; 95% CI, 0.56-1.06; P=0.10), 3-years RR (OR=0.79; 95% CI, 0.62-1.01; P=0.06),1-year overall survival outcome(OS) (OR=0.90; 95% CI, 0.63-1.28; P=0.57), 3-year OS(OR=1.16; 95% CI, 0.83-1.62; P=0.38), 5-year OS(OR=1.04; 95% CI, 0.76-1.40; P=0.82),1-year disease-free survival rate(DFS) (OR=0.80; 95%CI, 0.49-1.30; P=0.36), 3-year DFS(OR=0.99; 95%CI, 0.64-1.55; P=0.98), and 5-year DFS(OR=0.88; 95%CI, 0.60-1.28; P=0.50). Subgroup analysis shows a difference in the use of leukocyte depletion filters group of 5-year RR(OR=0.73; 95%CI, 0.55-0.96; P=0.03). No significant differences are found in other subgroups.

Conclusions

IBSA provides comparable survival outcomes relative to allogeneic blood transfusion and does not increase the tumor recurrence for HCC patients after LT.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42022295479.

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.

Cell Salvage During Liver Transplantation for Hepatocellular Carcinoma: A Retrospective Analysis of Tumor Recurrence Following Irradiation of the Salvaged Blood

BACKGROUND

Orthotopic liver transplantation (OLT) is the treatment option for early-stage hepatocellular carcinoma (HCC). OLT is often associated with high blood loss, requiring blood transfusion. Retransfusion of autologous blood is a key part of blood conservation. There are, however, concerns that the retransfusion of salvaged blood might cause the spread of cancer cells and induce metastasis. Irradiation of salvaged blood before retransfusion eliminates viable cancer cells. Here, we analyzed the incidence of tumor recurrence in patients with HCC undergoing OLT who received irradiated cell-salvaged blood during transplant surgery.

METHODS

We retrospectively analyzed patients undergoing OLT for HCC between 2002 and 2018 at our center. We compared the tumour recurrence in patients who received no retransfusion of autologous blood with patients who received autologous blood with or without preceding irradiation of the blood.

RESULTS

Fifty-one (40 male, 11 female) patients were included in the analysis; 10 patients developed tumor recurrence within a time period of 2.45 ± 2.0 years. Statistical analysis revealed that there was no significant difference in tumor recurrence between patients who received autologous blood with or without irradiation.

CONCLUSION

Intraoperative transfusion of cell-salvaged blood did not increase tumor recurrence rates. Cell salvage should be used in liver transplantation of HCC patients as part of a blood conservation strategy. The effect of blood irradiation on tumor recurrence could not be definitively evaluated.

Perioperative hemostatic management in the cirrhotic patient: a position paper on behalf of the Liver Intensive Care Group of Europe (LICAGE)

Recent data demonstrated that amongst patients undergoing elective surgery the prevalence of cirrhosis is 0.8% equating to approximately 25 million cirrhotic patients undergoing surgery each year worldwide. Overall, the presence of cirrhosis is independently associated with 47% increased risk of postoperative complications and over two and a half-increased risk of in-hospital mortality in patients undergoing elective surgery. In particular, perioperative patients with chronic liver disease have long been assumed to have a major bleeding risk on the basis of abnormal results for standard tests of hemostasis. However, recent evidence outlined significant changes to traditional knowledge and beliefs and, nowadays, with more sophisticated laboratory tests, it has been shown that patients with chronic liver disease may be in hemostatic balance as a result of concomitant changes in both pro- and antihemostatic pathways. The aim of this paper endorsed by the Liver Intensive Care Group of Europe was to provide an up-to-date overview of coagulation management in perioperative patients with chronic liver disease focusing on patient blood management, monitoring of hemostasis, and current role of hemostatic agents.

Intraoperative cell salvage with autologous transfusion in liver transplantation

Liver transplant (LT) is the primary treatment for patients with end-stage liver disease. About 25000 LTs are performed annually in the world. The potential for intraoperative bleeding is quite variable. However, massive bleeding is common and requires blood transfusion. Allogeneic blood transfusion has an immunosuppressive effect and an impact on recipient survival, in addition to the risk of transmission of viral infections and transfusion errors, among others. Techniques to prevent excessive bleeding or to use autologous blood have been proposed to minimize the negative effects of allogeneic blood transfusion. Intraoperative reinfusion of autologous blood is possible through previous self-donation or blood collected during the operation. However, LT does not normally allow autologous transfusion by prior self-donation. Hence, using autologous blood collected intraoperatively is the most feasible option. The use of intraoperative blood salvage autotransfusion (IBSA) minimizes the perioperative use of allogeneic blood, preventing negative transfusion effects without negatively impacting other clinical outcomes. The use of IBSA in patients with cancer is still a matter of debate due to the theoretical risk of reinfusion of tumor cells. However, studies have demonstrated the safety of IBSA in several surgical procedures, including LT for hepatocellular carcinoma. Considering the literature available to date, we can state that IBSA should be routinely used in LT, both in patients with cancer and in patients with benign diseases.

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.

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

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

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.

Liver transplantation in Jehovah's Witnesses: two cases report

Liver transplantation is especially challenging in patients who are Jehovah's Witnesses because their religious beliefs prohibit the receipt of blood products. We present two cases of living donor liver transplantation performed in adult Jehovah's Witnesses in South Korea without the use of blood products. In the first case, preoperative erythropoiesisstimulation therapy increased hemoglobin levels from 8.1 to 13.1 g/dl after 9 weeks. In the second case, hemoglobin levels increased from 7.4 to 10.8 g/dl after 6 months of erythropoiesis-stimulation therapy. With the combination of acute normovolemic hemodilution, intraoperative cell salvage, and use of transfusion alternatives, liver transplantation was successfully performed without transfusion of blood products.

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.

Coagulopathy and transfusion therapy in pediatric liver transplantation

Bleeding and coagulopathy are critical issues complicating pediatric liver transplantation and contributing to morbidity and mortality in the cirrhotic child. The complexity of coagulopathy in the pediatric patient is illustrated by the interaction between three basic models. The first model, "developmental hemostasis", demonstrates how a different balance between pro- and anticoagulation factors leads to a normal hemostatic capacity in the pediatric patient at various ages. The second, the "cell based model of coagulation", takes into account the interaction between plasma proteins and cells. In the last, the concept of "rebalanced coagulation" highlights how the reduction of both pro- and anticoagulation factors leads to a normal, although unstable, coagulation profile. This new concept has led to the development of novel techniques used to analyze the coagulation capacity of whole blood for all patients. For example, viscoelastic methodologies are increasingly used on adult patients to test hemostatic capacity and to guide transfusion protocols. However, results are often confounding or have limited impact on morbidity and mortality. Moreover, data from pediatric patients remain inadequate. In addition, several interventions have been proposed to limit blood loss during transplantation, including the use of antifibrinolytic drugs and surgical techniques, such as the piggyback and lowering the central venous pressure during the hepatic dissection phase. The rationale for the use of these interventions is quite solid and has led to their incorporation into clinical practice; yet few of them have been rigorously tested in adults, let alone in children. Finally, the postoperative period in pediatric cohorts of patients has been characterized by an enhanced risk of hepatic vessel thrombosis. Thrombosis in fact remains the primary cause of early graft failure and re-transplantation within the first 30 d following surgery, and it occurs despite prolongation of standard coagulation assays. Data, however, are currently lacking regarding the use of anti-aggregation/anticoagulation therapies and how to best monitor for thrombosis in the early postoperative period in pediatric patients. Therefore, further studies are necessary to elucidate the interaction between the development of the coagulation system and cirrhosis in children. Moreover, strategies to optimize blood transfusion and anticoagulation must be tested specifically in pediatric patients. In conclusion, data from the adult world can be translated with difficulty into the pediatric field as indication for transplantation, baseline pathologies and levels of pro- and anticoagulation factors are not comparable between the two populations.

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.

Review of anesthesia in liver transplantation

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

Transfusion and coagulation management in liver transplantation

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

Effect of autotransfusion system on tumor recurrence and survival in hepatocellular carcinoma patients

AIM: To investigate the therapeutic efficacy and safety of continuous autotransfusion system (CATS) during liver transplantation of hepatocellular carcinoma patients.

METHODS: Eighty-three hepatocellular carcinoma (HCC) patients who underwent liver transplantation with intraoperative CATS (n = 24, CATS group) and without (n = 59, non-CATS group) between April 2006 and November 2011 at the Liver Transplant Institute of Inonu University were analyzed retrospectively. Postoperative HCC recurrence was monitored by measuring alpha-fetoprotein (AFP) levels at 3-mo intervals and performing imaging analysis by thoracoabdominal multidetector computed tomography at 6-month intervals. Inter-group differences in recurrence and correlations between demographic, clinical, and pathological data were assessed by ANOVA and χ² tests. Overall and disease-free survivals were calculated by the univariate Kaplan-Meier method.

RESULTS: Of the 83 liver transplanted HCC patients, 89.2% were male and the overall mean age was 51.3 ± 8.9 years (range: 18-69 years). The CATS and non-CATS groups showed no statistically significant differences in age, sex ratio, body mass index, underlying disease, donor type, graft-to-recipient weight ratio, Child-Pugh and Model for End-Stage Liver Disease scores, number of tumors, tumor size, AFP level, Milan and University of California San Francisco selection criteria, tumor differentiation, macrovascular invasion, median hospital stay, recurrence rate, recurrence site, or mortality rate. The mean follow-up time of the non-CATS group was 17.9 ± 12.8 mo, during which systemic metastasis and/or locoregional recurrence developed in 25.4% of the patients. The mean follow-up time for the CATS group was 25.8 ± 15.1 mo, during which systemic metastasis and/or locoregional recurrence was detected in 29.2% of the patients. There was no significant difference between the CATS and non-CATS groups in recurrence rate or site. Additionally, no significant differences existed between the groups in overall or disease-free survival.

CONCLUSION: CATS is a safe procedure and may decrease the risk of tumor recurrence in HCC patients.

Blood loss, predictors of bleeding, transfusion practice and strategies of blood cell salvaging during liver transplantation

Blood loss during liver transplantation (OLTx) is a common consequence of pre-existing abnormalities of the hemostatic system, portal hypertension with multiple collateral vessels, portal vein thrombosis, previous abdominal surgery, splenomegaly, and poor “functional” recovery of the new liver. The intrinsic coagulopathic features of end stage cirrhosis along with surgical technical difficulties make transfusion-free liver transplantation a major challenge, and, despite the improvements in understanding of intraoperative coagulation profiles and strategies to control blood loss, the requirements for blood or blood products remains high. The impact of blood transfusion has been shown to be significant and independent of other well-known predictors of posttransplant-outcome. Negative effects on immunomodulation and an increased risk of postoperative complications and mortality have been repeatedly demonstrated. Isovolemic hemodilution, the extensive utilization of thromboelastogram and the use of autotransfusion devices are among the commonly adopted procedures to limit the amount of blood transfusion. The use of intraoperative blood salvage and autologous blood transfusion should still be considered an important method to reduce the need for allogenic blood and the associated complications. In this article we report on the common preoperative and intraoperative factors contributing to blood loss, intraoperative transfusion practices, anesthesiologic and surgical strategies to prevent blood loss, and on intraoperative blood salvaging techniques and autologous blood transfusion. Even though the advances in surgical technique and anesthetic management, as well as a better understanding of the risk factors, have resulted in a steady decrease in intraoperative bleeding, most patients still bleed extensively. Blood transfusion therapy is still a critical feature during OLTx and various studies have shown a large variability in the use of blood products among different centers and even among individual anesthesiologists within the same center. Unfortunately, despite the large number of OLTx performed each year, there is still paucity of large randomized, multicentre, and controlled studies which indicate how to prevent bleeding, the transfusion needs and thresholds, and the “evidence based” perioperative strategies to reduce the amount of transfusion.

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.

Liver transplantation: issues and nursing care requirements

Liver transplantation has evolved into an accepted treatment for many suffering from end-stage liver failure. The complex nature of the liver results in every organ system being impacted by either the failing or the transplanted liver. Organ shortage remains problematic, and work to ensure maximizing the organ donor pool as well as the success of each organ transplant continues. The clinical care and condition of the patient before transplant can impact the outcome after transplant. Nurses can play an integral role in early identification of graft dysfunction, rejection, or infection. Because of the intimate and large amount of time that the nurse is at the patient’s bedside, he or she is often in a position to monitor for potential risks to the patient and take corrective action.

Differential effects of plasma and red blood cell transfusions on acute lung injury and infection risk following liver transplantation

Patients with chronic liver disease have an increased risk of developing transfusion-related acute lung injury (TRALI) from plasma-containing blood products. Similarly, red blood cell transfusions have been associated with postoperative and nosocomial infections in surgical and critical care populations. Patients undergoing liver transplantation receive large amounts of cellular and plasma-containing blood components, but it is presently unclear which blood components are associated with these postoperative complications. A retrospective cohort study of 525 consecutive liver transplant patients revealed a perioperative TRALI rate of 1.3% (7/525, 95% confidence interval = 0.6%-2.7%), which was associated with increases in the hospital mortality rate [28.6% (2/7) versus 2.9% (15/518), P = 0.02] and the intensive care unit length of stay [2 (1-11 days) versus 0 days (0-2 days), P = 0.03]. Only high-plasma-containing blood products (plasma and platelets) were associated with the development of TRALI. Seventy-four of 525 patients (14.1%) developed a postoperative infection, and this was also associated with increased in-hospital mortality [10.8% (8/74) versus 2.0% (9/451), P < 0.01] and a prolonged length of stay. Multivariate logistic regression determined that the number of transfused red blood cell units (adjusted odds ratio = 1.08, 95% confidence interval = 1.02-1.14, P < 0.01), the presence of perioperative renal dysfunction, and reoperation were significantly associated with postoperative infection. In conclusion, patients undergoing liver transplantation have a high risk of developing postoperative complications from blood transfusion. Plasma-containing blood products were associated with the development of TRALI, whereas red blood cells were associated with the development of postoperative infections in a dose-dependent manner.

Cell salvage as part of a blood conservation strategy in anaesthesia

The use of intraoperative cell salvage and autologous blood transfusion has become an important method of blood conservation. The main aim of autologous transfusion is to reduce the need for allogeneic blood transfusion and its associated complications. Allogeneic blood transfusion has been associated with increased risk of tumour recurrence, postoperative infection, acute lung injury, perioperative myocardial infarction, postoperative low-output cardiac failure, and increased mortality. We have reviewed the current evidence for cell salvage in modern surgical practice and examined the controversial issues, such as the use of cell salvage in obstetrics, and in patients with malignancy, or intra-abdominal or systemic sepsis. Cell salvage has been demonstrated to be safe and effective at reducing allogeneic blood transfusion requirements in adult elective surgery, with stronger evidence in cardiac and orthopaedic surgery. Prolonged use of cell salvage with large-volume autotransfusion may be associated with dilution of clotting factors and thrombocytopenia, and regular laboratory or near-patient monitoring is required, along with appropriate blood product use. Cell salvage should be considered in all cases where significant blood loss (>1000 ml) is expected or possible, where patients refuse allogeneic blood products or they are anaemic. The use of cell salvage in combination with a leucocyte depletion filter appears to be safe in obstetrics and cases of malignancy; however, further trials are required before definitive guidance may be provided. The only absolute contraindication to the use of cell salvage and autologous blood transfusion is patient refusal.

Effects of phlebotomy and phenylephrine infusion on portal venous pressure and systemic hemodynamics during liver transplantation

BACKGROUND

A regimen of fluid restriction, phlebotomy, vasopressors, and strict, protocol-guided product replacement has been associated with low blood product use during orthotopic liver transplantation. However, the physiologic basis of this strategy remains unclear. We hypothesized that a reduction of intravascular volume by phlebotomy would cause a decrease in portal venous pressure (PVP), which would be sustained during subsequent phenylephrine infusion, possibly explaining reduced bleeding. Because phenylephrine may increase central venous pressure (CVP), we questioned the validity of CVP as a correlate of cardiac filling in this context and compared it with other pulmonary artery catheter and transesophageal echocardiography-derived parameters. In particular, because optimal views for echocardiographic estimation of preload and stroke volume are not always applicable during liver transplantation, we evaluated the use of transmitral flow (TMF) early peak (E) velocity as a surrogate.

METHODS

In study 1, the changes in directly measured PVP and CVP were recorded before and after phlebotomy and phenylephrine infusion in 10 patients near the end of the dissection phase of liver transplantation. In study 2, transesophageal echocardiography-derived TMF velocity in early diastole was measured in 20 patients, and the changes were compared with changes in CVP, pulmonary artery pressure (PAP), pulmonary capillary wedge pressure (PCWP), cardiac output (CO), and calculated systemic vascular resistance (SVR) at the following times: postinduction, postphlebotomy, preclamping of the inferior vena cava, during clamping, and postunclamping.

RESULTS

Phlebotomy decreased PVP along with CO, PAP, PCWP, CVP, and TMF E velocity. Phenylephrine given after phlebotomy increased CVP, SVR, and arterial blood pressure but had no significant effect on CO, PAP, PCWP, or PVP. The change in TMF E velocity correlated well with the change in CO (Pearson correlation coefficient 95% confidence interval 0.738-0.917, P< or =0.015) but less well with the change in PAP (0.554-0.762, P< or =0.012) and PCWP (0.576-0.692, P< or =0.008). TMF E velocity did not correlate significantly with CVP or calculated SVR.

CONCLUSION

Phlebotomy during the dissection phase of liver transplantation decreased PVP, which was unaffected when phenylephrine infusion was used to restore systemic arterial pressure. This may contribute to a decrease in operative blood loss. CVP often increased in response to phenylephrine infusion and did not seem to reflect cardiac filling. The changes in TMF E velocity correlated well with the changes in CO, PAP, and PCWP during liver transplantation but not with the changes in CVP.

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

BACKGROUND

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

METHOD

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

RESULT

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

CONCLUSION

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