Coagulation defects in cirrhosis--old dogmas not yet ready for burial

Association Between Intraoperative Platelet Transfusion and Early Graft Regeneration in Living Donor Liver Transplantation

OBJECTIVE

To evaluate the association between anesthetic management before and after graft reperfusion and early graft regeneration in living donor liver transplantation (LDLT).

BACKGROUND

Sufficient graft regeneration is essential for the success of LDLT. Diverse signals start to trigger liver regeneration immediately after graft reperfusion.

METHODS

Graft volume at 14 ± 2 days after LDLT was measured in 379 consecutive recipients using computed tomography images with 3-dimensional reconstruction. The association between anesthetic variables and the degree of graft regeneration for 2 weeks was analyzed using simple and multiple linear regressions. The anesthetic variables included hemodynamics, laboratory measurements, vasoactive drugs, and blood products transfusion.

RESULTS

The degree of graft regeneration for 2 weeks was 52% in median and ranged from 5% to 123%. Platelet transfusion was identified as the sole independent anesthetic factor contributing to graft regeneration. Platelet concentrate transfusion of 1 to 6 units vs none was correlated with a 6.5% increase in graft regeneration (P = 0.012). Platelet concentrate transfusion of more than 6 units vs none was further correlated with an 18.4% increase in regeneration (P < 0.001). In the subgroup of recipients without intraoperative platelet transfusion, mean platelet count measured during the intraoperative reperfusion phase was positively associated with graft regeneration (P = 0.033).

CONCLUSIONS

Graft regeneration after LDLT increased in relation to a graded increase in the amount of transfused platelets and higher postreperfusion platelet counts during surgery. These results offer additional evidence regarding the important role of platelets in initiating liver regeneration and, furthermore, the indications for and the benefits vs risks of platelet transfusion during LDLT.

Hypersplenism is correlated with increased risk of hepatocellular carcinoma in patients with post-hepatitis cirrhosis

Several risk factors exist for hepatocellular carcinoma in patients with post-hepatitis cirrhosis (PHC), including hypersplenism. Splenectomy is a common but controversial procedure in the management of hypersplenism, but its impact on hepatocellular carcinoma (HCC) remains uncertain. We conducted a hospital-based study of PHC patients to identify potential risk factors, including a history of splenectomy, which has been associated with progression from PHC to HCC. From 2002 to 2012, 2678 patients developed hypersplenism secondary to PHC. Of these patients, 828 developed HCC and 1850 did not. Potential risk factors of HCC were determined by univariate and multivariate analyses to exclude confounding variables. Odds ratios (ORs) and 95 % confidence intervals (95 % CIs) were determined for each factor. Many factors, such as liver function, platelet (PLT) counts, Child-Pugh class, and history of hepatitis, were associated with progression to HCC. PHC patients with hypersplenism who displayed elevated levels of alanine transaminase (ALT), aspartate transaminase (AST), γ-glutamyltransferase (GGT), ALK, phosphatase, and prolonged prothrombin time (PT) had a significantly increased risk of HCC. However, the patients who had splenectomy showed better liver function test results and less progression to HCC. In patients with PHC and hypersplenism, abnormal levels of ALT, AST, ALP, and GGT and prolonged PT are risk factors of HCC. Splenectomy, as the intervention method of hypersplenism, is performed less frequently in patients who developed HCC than in patients who did not develop HCC. Therefore, splenectomy may act as an independent factor that is significantly associated with HCC development.

Glycated Hemoglobin Levels in Patients with Decompensated Cirrhosis

Introduction. Aim of this study is to determine if HbA1c levels are a reliable predictor of glycemic control in patients with decompensated cirrhosis. Methods. 200 unique patients referred for liver transplantation at University of Tennessee/Methodist University Transplant Institute with a HbA1c result were included. Three glucose levels prior to the "measured" A1c (MA1c) were input into an HbA1c calculator from the American Diabetes Association website to determine the "calculated" A1c (CA1c). The differences between MA1c and CA1c levels were computed. Patients were divided into three groups: group A, difference of <0.5; group B, 0.51-1.5; and group C, >1.5. Results. 97 (49%) patients had hemoglobin A1c of less than 5%. Discordance between calculated and measured HbA1c of >0.5% was seen in 47% (n = 94). Higher level of discordance of greater than >1.5 was in 12% of patients (n = 24). Hemoglobin was an independent predictor for higher discordance (odds ratio 0.77 95%, CI 0.60-0.99, and p value 0.04). HbA1c was an independent predictor of occurrence of HCC (OR 2.69 955, CI 1.38-5.43, and p value 0.008). Conclusion. HbA1c is not a reliable predictor of glycemic control in patients with decompensated cirrhosis, especially in those with severe anemia.

Spectrum of anemia associated with chronic liver disease

Anemia of diverse etiology is a common complication of chronic liver diseases. The causes of anemia include acute or chronic gastrointestinal hemorrhage, and hypersplenism secondary to portal hypertension. Severe hepatocellular disease predisposes to hemorrhage because of impaired blood coagulation caused by deficiency of blood coagulation factors synthesized by hepatocytes, and/or thrombocytopenia. Aplastic anemia, which is characterized by pancytopenia and hypocellular bone marrow, may follow the development of hepatitis. Its presentation includes progressive anemia and hemorrhagic manifestations. Hematological complications of combination therapy for chronic viral hepatitis include clinically significant anemia, secondary to treatment with ribavirin and/or interferon. Ribavirin-induced hemolysis can be reversed by reducing the dose of the drug or discontinuing it altogether. Interferons may contribute to anemia by inducing bone marrow suppression. Alcohol ingestion is implicated in the pathogenesis of chronic liver disease and may contribute to associated anemia. In patients with chronic liver disease, anemia may be exacerbated by deficiency of folic acid and/or vitamin B12 that can occur secondary to inadequate dietary intake or malabsorption.

No evidence for systemic platelet activation during or after orthotopic liver transplantation

Platelet function is thought to deteriorate during liver transplantation as a result of platelet activation and proteolysis of platelet receptors by plasmin following reperfusion. However, this hypothesis has never been formally tested. Twenty patients undergoing a first or second liver transplant were included in the study. Blood samples were taken at standardized time points during transplantation and up to 10 days after transplantation. Platelet activation was assessed by detection of the activation markers P-selectin and activated integrin alphaIIbbeta3 with flow cytometry. Proteolytic cleavage of platelet receptors was assessed by flow cytometry measurement of the constitutively expressed platelet receptors glycoprotein Ibalpha and integrin alphaIIbbeta3. In addition, using enzyme-linked immunosorbent assay techniques, we measured plasma levels of platelet activation products beta-thromboglobulin and platelet factor 4 and plasma levels of cleaved fragments of glycoproteins Ibalpha and V. Flow cytometry analyses provided no evidence of substantial platelet activation during transplantation. In fact, the expression of activated integrin alphaIIbbeta3 decreased postoperatively; this indicated that platelets were in a slightly activated state prior to surgery. Plasma levels of beta-thromboglobulin and platelet factor 4 also substantially decreased after transplantation. In addition, no changes were observed in the constitutively expressed platelet receptors or in the plasma levels of platelet receptor fragments, and this indicated a lack of substantial receptor proteolysis. In conclusion, no evidence was found for significant activation of circulating blood platelets or the proteolysis of key platelet receptors during liver transplantation. These findings suggest that the platelet functional capacity does not decrease during liver transplantation. Liver Transpl 15:956-962, 2009. (c) 2009 AASLD.