Assessment of hemostatic profile in patients with mild to advanced liver cirrhosis.

BACKGROUND: Hemostasis of patients suffering from liver cirrhosis is challenging due to both, pro- and anticoagulatory disorders leading to hemostatic alterations with distinct abnormalities of coagulation. Pathological changes in conventional coagulation analysis and platelet count are common manifestations of decreased liver synthesis of coagulation factors and reduced platelet count in these patients. However, conventional coagulation analysis and platelet count do not reflect in-vivo coagulation status or platelet function. The purpose of this present observational study was therefore to assess the haemostatic profile including plasmatic coagulation using thrombelastometry and impedance aggregometry for platelet function in patients suffering from liver cirrhosis. AIM: To assess the hemostatic profile of cirrhotic patients according to model for end-stage liver disease (MELD) score. METHODS: Our study included both in- and outpatients suffering from liver cirrhosis attending the out- and inpatient care of the department of hepatology. Demographic and biochemical data as well as medical history including cause of liver cirrhosis, end stage kidney failure and medication with anticoagulants were recorded. To assess the hemostatic profile, platelet function was analyzed by multiple electrode aggregometry (MEA) using Multiplate® (ADP-, ASPI- and TRAP-test) and thrombelastometry using ROTEM® (EXTEM, INTEM, FIBTEM). Data were compared using Mann-Whitney U- or χ 2-test. Spearman correlation was performed to analyze the association between MELD Score and results of thrombelastometry and MEA. RESULTS: A total of 68 patients attending the out- and inpatient care suffering from liver cirrhosis were screened. Of these, 50 patients were included and assigned to groups according to MELD score 6 to 11 (n = 25) or ≥ 17 (n = 25). Baseline patient characteristics revealed significant differences for MELD score (8 vs 22, P < 0.0001) and underlying laboratory parameters (international normalized ratio, bilirubine, creatinine) as well as fibrinogen level (275 mg/dL vs 209 mg/dL, P = 0.006) and aPTT (30 s vs 35 s, P = 0.047). MEA showed a moderately impaired platelet function (medians: AUCADP = 43U, AUCASPI = 71U, AUCTRAP = 92U) but no significant differences between both groups. Thrombelastometry using ROTEM® (EXTEM, INTEM, FIBTEM) revealed values within normal range in both groups. No significant correlation was observed between MELD score and results of MEA/thrombelastometry. CONCLUSION: Our data demonstrate a partially impaired hemostatic profile in liver cirrhosis patients unrelated to MELD score. An individual assessment of a potential coagulopathy should therefore be considered.

Assessment of hemostatic changes after initiation of continuous venovenous hemodialysis.

BACKGROUND: Continuous renal replacement therapy (CRRT) is a standard therapy in critically ill patients suffering from acute kidney injury (AKI). Extracorporeal circulation and exposure to foreign surfaces during CRRT may induce disturbances in hemostasis, particularly in platelet function. The present study described the hemostatic changes associated with CRRT and aimed to identify the independent predictors of premature clotting of the circuit. METHODS: In a prospective cohort mono-center study, patients were assessed for eligibility if they were i) diagnosed with AKI and ii) assigned to receive CRRT for the first time. Patients were included in the study if their platelet count was greater than 100/nL prior to inclusion in the study. After initiation of CRRT, aggregometric [Multiplate, Roche, Grenzach, Germany: Arachidonic acid (ASPItest)-, ADP (ADPtest)- and Thrombin (TRAPtest)-induced platelet aggregation] and viscoelastic (ROTEM; TEM International, Munich, Germany) analyses were performed immediately before (Baseline, T1) and 6 hours (T2), 12 hours (T3), 24 hours (T4), and 48 hours (T5) after initiation of CRRT. Conventional laboratory coagulation analyses were routinely performed twice a day. Arachidonic acid- and ADP-induced platelet aggregations were defined as primary endpoints. RESULTS: A total of 127 patients were screened for eligibility, and 50 patients were enrolled in this study. Aggregometric analyses showed that arachidonic acid-induced platelet aggregation was significantly reduced at T2 [532 (210/1105) median (25th/75th percentile) AU*min] compared to the Baseline at T1 [780 (297/1156), p = 0.007] and remained unchanged from T2 onward. Platelet aggregation in the ADPtest and TRAPtest remained unchanged during the study period. Viscoelastic and conventional coagulation analyses indicated a progredient increase of clot firmness. In total, 76 filter sets (an average of 1.5 per patient) were used, and 26 filter sets occluded prematurely after an average treatment time of 17 ± 12 hours. No predictors for premature clotting of the circuit were identified. CONCLUSIONS: The results of the present study indicate that CRRT may lead to impaired primary hemostasis as shown by a decrease in ex vivo arachidonic acid-induced platelet aggregation. Moreover, viscoelastic measure indicate a fibrinogen-associated trend of increasing clot firmness during the study period. Further studies are needed to analyze whether these findings are of hemostatic relevance.