Coagulation pattern in critical liver dysfunction. Curr Opin Crit Care. 2013;19:142-148. [PMID: 23400090 DOI: 10.1097/mcc.0b013e32835ebb52]

A Mortality Prediction Model for Cirrhotic Patients With Blunt Abdominal Trauma: A Single-Center Retrospective Study

PURPOSE

Owing to its impaired production of coagulation factors and immunosuppressed state, liver cirrhosis is recognized as a detrimental factor in patients with blunt abdominal trauma (BAT). The aim of this study was to evaluate cirrhosis-associated factors contributing to mortality in patients suffering from BAT with preexisting cirrhosis and develop a corresponding prediction model.

METHODS

A retrospective observational study of patients with BAT from May 2008 to December 2022 in a level-I trauma center was conducted. Propensity score matching (PSM) was performed at a 1:2 ratio to compare mortality, hemorrhage-related complications, length of stay (LOS), and intensive care unit (ICU) LOS among patients with and without preexisting cirrhosis. A subset analysis using multivariate logistic regression (MLR) was conducted to identify independent cirrhosis-associated factors of mortality among cirrhotic patients.

RESULTS

Out of 5705 patients suffering from BAT, 88 (1.5%) had preexisting cirrhosis. A well-balanced PSM revealed that patients with cirrhosis had significantly higher mortality (21.6% vs. 6.8%, p < 0.001) and hemorrhage-related complication (31.8% vs. 19.9%, p = 0.032) rates. Among patients suffering from BAT with preexisting cirrhosis (N = 88), the MLR analysis demonstrated that the prothrombin time-international normalized ratio (PT-INR) and creatinine level were independent factors of mortality. A 0.1 unit increase in the PT-INR increased the odds of mortality by 58.2% (odds ratio = 1.582, 95% CI: 1.244-2.012, and p < 0.001), whereas a 1 mg/dL increase in the creatinine level increased the odds of mortality by 90.3% (odds ratio = 1.903, 95% CI: 1.082-3.347, and p = 0.026).

CONCLUSIONS

Compared with noncirrhotic patients, cirrhotic patients had significantly higher mortality and hemorrhage-related complication rates. The PT-INR and creatinine level are identified as predictors of mortality for patients suffering from BAT with preexisting cirrhosis. In the management of patients with BAT, early and routine examinations of PT-INR and creatinine are encouraged, especially for patients with preexisting cirrhosis.

Practical Considerations for Extracorporeal Membrane Oxygenation Use During Orthotopic Liver Transplantation

Patients undergoing liver transplantation infrequently require extracorporeal membrane oxygenation (ECMO) support. However, when ECMO is required in the peritransplant period, several key considerations are required to maximize the efficacy of its support and minimize the risks of complications. This review seeks to briefly summarize the existing data supporting the use of ECMO in liver transplant patients and offers expert technical and practical advice from the authors' high-volume liver transplant center and ECMO program.

Impact of pre-existing medical conditions on mortality in geriatric trauma: a nationwide study in Japan

PURPOSE

To investigate the relationship between pre-existing medical conditions and outcomes in elderly trauma patients in Japan.

METHODS

This multicenter observational study utilized data from the Japan Trauma Data Bank (JTDB) from 2019 to 2020. The primary outcome was in-hospital mortality. Factors associated with in-hospital mortality were identified using multivariate logistic regression analysis, from which adjusted odds ratios (AOR) and 95% confidence intervals (CI) were determined.

RESULTS

Of the participants during the study period, 19,598 patients were included in the analysis. Among the pre-existing medical conditions, moderate or severe liver disease showed the strongest positive association with in-hospital mortality (AOR: 7.087, 95% CI: 3.194-15.722), followed by multiple malignancies (AOR: 3.490, 95% CI: 1.046-11.641), congestive heart failure (AOR: 2.572, 95% CI: 1.920-3.445), and moderate or severe renal disease (AOR: 2.256, 95% CI: 1.584-3.215).

CONCLUSION

Data from JTDB suggests that pre-existing conditions like moderate or severe liver disease, congestive heart failure, and moderate or severe renal disease in elderly trauma patients are positively correlated with in-hospital mortality.

Viscoelastic Hemostatic Testing as a Diagnostic Tool for Hypercoagulability in Liver Transplantation: A Narrative Review

Liver transplantation is a complex surgical procedure in which various forms of coagulation dysfunction can occur, including perioperative hypercoagulability. The hemostasis balance in liver graft recipients with end-stage liver disease can shift to thrombosis or haemorrhage, depending on the associated risk factors and clinical conditions. Hypercoagulability can result in serious complications such as thromboembolism, which can affect the vessels of the newly transplanted liver graft. Standard coagulation tests (SCTs), such as prothrombin time and activated partial thromboplastin time (aPTT), have a poor ability to diagnose and monitor an early stage of hypercoagulability. Recent studies demonstrated that viscoelastic hemostatic elastic tests (VETs), such as rotational thromboelastometry (ROTEM) and thromboelastography (TEG), are promising alternative tools for diagnosing hypercoagulability disorders. VETs measure clotting and clot formation time, clot strength (maximum clot firmness), fibrin and platelet contribution to clot firmness, and fibrinolysis, which makes them more sensitive in identifying liver graft recipients at risk for thrombosis as compared with SCTs. However, developing evidence-based guidelines for the prophylaxis and treatment of hypercoagulability based on VET results is still needed.

The negative effect of preexisting cirrhosis on blunt liver trauma patients: a multifaceted approach from the trauma quality improvement program database

PURPOSE

To assess the impact of pre-existing cirrhosis on the outcomes of non-operatively managed blunt liver trauma within the Trauma Quality Improvement Program (TQIP) database.

METHODS

A study of non-operatively managed blunt liver injury patients from 2016 to 2019 was conducted. Propensity score matching analyzed mortality, complications, and hospital length of stay (LOS) for patients with and without cirrhosis. The effect of transcatheter arterial embolization (TAE) was determined using multivariate logistic regression.

RESULTS

Out of 63,946 patients, 767 (1.2%) had pre-existing cirrhosis. Following 1:1 matching, those with cirrhosis experienced more hemorrhage (TAE need: 5.7% vs. 2.7%; transfusion volume: 639.1 vs. 259.3 ml), complications (acute kidney injury: 5.1% vs. 2.8%; sepsis: 2.4% vs. 1.0%), and poorer outcomes (mortality: 19.5% vs. 10.2%; hospital LOS: 11.6 vs. 8.4 days; ICU LOS: 12.1 vs. 7.4 days; ventilator days: 7.6 vs. 1.6). Notably, TAE was associated with increased mortality in cirrhotic patients (odds ratio: 4.093) but did not significantly affect mortality in patients without cirrhosis.

CONCLUSIONS

Within TQIP, pre-existing cirrhosis is a significant negative determinant for outcomes in blunt liver trauma. Cirrhotic patients undergoing TAE for hemostasis face greater mortality risk than non-cirrhotic counterparts.

Anaesthesia management for liver transplantation: A narrative review

Orthotopic liver transplantation is the definitive standard treatment for end-stage liver disease. Orthotopic liver transplantation anaesthesia management is a complex procedure that requires a multidisciplinary team approach. Understanding the complex pathophysiology of end-stage liver disease and its complications in the affected systems is essential for proper anaesthesia management in orthotopic liver transplantation. Orthotopic liver transplantation is a dynamic process, and preoperative optimisation is essential in these patients. Therefore, anaesthesiologists should focus on rapidly fluctuating physiology, haemodynamics, metabolic, and coagulation status in the anaesthesia management of these patients. Perioperative care and anaesthesia for orthotopic liver transplantation can be divided into preoperative evaluation, anaesthesia induction and management, dissection, anhepatic, neo-hepatic, and postoperative care, with essential anaesthetic considerations at each point. Considering the clinical situation, haemodynamic changes, misapplications, knowledge, attitude, and multimodal and multidisciplinary approach are vital in anaesthesia and the perioperative period. In our review, in line with the literature, we aimed to present the perioperative and anaesthesia management in orthotopic liver transplantation patients.

A Comprehensive Review of the Diagnosis and Management of Acute Liver Failure

Acute liver failure (ALF) is a rare and specific form of severe hepatic dysfunction characterized by coagulopathy and hepatic encephalopathy in a patient with no known liver disease. ALF carries a high morbidity and mortality. Careful attention should be given to hemodynamics and metabolic parameters along with the active surveillance of infections. Timely transfer and supportive management are important in an intensive care unit in a liver transplant center. Identifying patients who will and will not improve with medical management and may need emergent liver transplantation is critical. In this review, we provide a comprehensive update on the etiology, diagnosis, and management of ALF.

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.

Individualized Management of Coagulopathy in Patients with End-Stage Liver Disease

Over the last decades, individualized approaches and a better understanding of coagulopathy complexity in end-stage liver disease (ESLD) patients has evolved. The risk of both thrombosis and bleeding during minimally invasive interventions or surgery is associated with a worse outcome in this patient population. Despite deranged quantitative and qualitative coagulation laboratory parameters, prophylactic coagulation management is unnecessary for patients who do not bleed. Transfusion of red blood cells (RBCs) and blood products carries independent risks for morbidity and mortality, including modulation of the immune system with increased risk for nosocomial infections. Optimal coagulation management in these complex patients should be based on the analysis of standard coagulation tests (SCTs) and viscoelastic tests (VETs). VETs represent an individualized approach to patients and can provide information about coagulation dynamics in a concise period of time. This narrative review will deliver the pathophysiology of deranged hemostasis in ESLD, explore the difficulties of evaluating the coagulopathies in liver disease patients, and examine the use of VET assays and management of coagulopathy using coagulation factors. Methods: A selective literature search with PubMed as the central database was performed with the following.

Haemostasis patterns in patients with acute-on-chronic liver failure and acute decompensation of cirrhosis including thromboelastometric tests with and without the addition of Protac: a pilot study

BACKGROUND

Thromboelastometry is considered the best method to assesses hemostasis in liver disease. Diagnostic performance could be improved by adding protein C activators such as thrombomodulin or Protac®. We assessed changes in ROTEM parameters after the addition of Protac® in patients with acute-on-chronic liver failure (ACLF), acute decompensation (AD), and healthy individuals (HI) to define different hemostasis patterns, considering standard and velocity ROTEM parameters, and assess whether Protac® can improve the definition of the pattern.

METHODS

Pre-test, we investigated whether diluted EXTEM reagent improved the effect of Protac® on the clotting time (CT)-ratio with and without Protac®. Ten ACLF and 20 AD patients and 21 HI were included in the main study.

RESULTS

Standard EXTEM was used in the main study. INTEM CFT, INTEM A5 (inverse), and INTEM TPI (inverse) were the parameters that best differentiated liver disease from HI (ROC AUC, 0.921, 0.906, and 0.928, respectively; all P-values < 0.001). Combining INTEM CFT with EXTEM LI60-ratio only slightly improved the diagnostic performance (ROC AUC, 0.948; P < 0.001). EXTEM LI60 and INTEM maxV-t were the parameters that best differentiated between ACLF and AD patients (ROC AUC, 0.743, P = 0.033; and 0.723, P = 0.050; respectively). Combining EXTEM LI60 + INTEM maxV-t moderately improved the diagnostic performance (ROC AUC, 0.81, P < 0.001).

CONCLUSIONS

ROTEM velocity, fibrinolysis parameters and the indices calculated improve the diagnosis in combination with standard parameters (e.g., CFT and A5). Ratios calculated with and without Protac® (e.g., EXTEM LI60-ratio) only slightly increased the diagnostic performance in discriminating hemostasis patterns.

Major Risk Factors for Mortality in Elderly and Non-Elderly Adult Patients Emergently Admitted for Blunt Chest Wall Trauma: Hospital Length of Stay as an Independent Predictor

Background: Blunt thoracic trauma is responsible for 35% of trauma-related deaths in the United States and significantly contributes to morbidity and healthcare-related financial strain. The goal of this study was to evaluate factors influencing mortality in patients emergently admitted with the primary diagnosis of blunt chest wall trauma. Methods: Adults emergently admitted for blunt chest trauma were assessed using the National Inpatient Sample Database, 2004–2014. Data regarding demographics, comorbidities, and outcomes were collected. Relationships were determined using univariable and multivariable logistic regression models. Results: In total, 1120 adult and 1038 elderly patients emergently admitted with blunt chest trauma were assessed; 46.3% were female, and 53.6% were male. The average ages of adult and elderly patients were 46.6 and 78.9 years, respectively. Elderly and adult patients both displayed mortality rates of 1%. The regression model showed HLOS and several comorbidities as the main risk factors of mortality Every additional day of hospitalization increased the odds of mortality by 9% (OR = 1.09, 95% CI = 1.01–1.18, p = 0.033). Mortality and liver disease were significantly associated (OR = 8.36, 95% CI = 2.23–31.37, p = 0.002). Respiratory disease and mortality rates demonstrated robust correlations (OR = 7.46, 95% CI = 1.63–34.11, p = 0.010). Trauma, burns, and poisons were associated with increased mortality (OR = 3.72, 95% CI = 1.18–11.71, p = 0.025). The presence of platelet/white blood cell disease correlated to higher mortality. (OR = 4.42, 95% CI = 1.09–17.91, p = 0.038).

The effect of cirrhosis on trauma outcomes: A systematic review and meta-analysis

BACKGROUND

The negative effect of cirrhosis on mortality following traumatic injury has been quantified in multiple observational studies. However, to our knowledge, the information contained in these studies has never been synthesized. The aims of this study were: (1) to determine the magnitude of the effect of liver cirrhosis on mortality, morbidity, and hospital course among trauma patients and (2) to analyze sources of study heterogeneity that may lead to differing estimates in the observed mortality rate among patients with cirrhosis.

METHODS

A systematic search of EMBASE and PubMed was conducted. Data were extracted from eligible studies and analyzed using a random-effects model to compare trauma outcomes in cirrhotic and noncirrhotic patients (PROSPERO Registration CRD42018088464). Mortality was the primary outcome. Secondary outcomes included complication rate, length of hospital stay, length of intensive care unit stay, and mechanical ventilation days.

RESULTS

Title and abstract review of 15,958 articles led to the identification of 31 relevant articles. Ultimately, 18 observational studies were included in this meta-analysis. The pooled effect sizes for mortality (odds ratio [OR], 4.52; 95% confidence interval [CI], 3.13-6.54) and complication rate (OR, 1.92; 95% CI, 1.30-2.85) were higher in the cirrhotic group than the noncirrhotic group. Trauma patients with cirrhosis also incurred longer hospital stays (mean difference, 3.81 days; 95% CI, 1.22-6.41) and longer ICU stays (mean difference, 2.40 days; 95% CI, 0.65-4.15). There was no difference in days spent on mechanical ventilation.

CONCLUSION

Preexisting liver cirrhosis is associated with increased mortality rate, complication rate, and length of hospitalization among trauma patients, even after adjusting for confounding factors and potential sources of between-study heterogeneity. Trauma patients with cirrhosis would benefit from heightened surveillance and injury prevention interventions.

LEVEL OF EVIDENCE

Systematic review and meta-analysis, level III.

Thrombin generation in patients with severe thermal injury

BACKGROUND

Severe burns can induce a hypercoagulable state which is not depicted in conventional coagulation assays. The thrombin generation assay allows global assessment of coagulation and can identify hypercoagulability. We report changes in thrombin generation in patients after severe burn injury.

METHODS

We measured TGA, rotational thrombelastometry and conventional assays in 20 consecutive patients with a total body surface area burned of >20% over a 2-week period: the day after burn trauma (A), the morning after surgical excision of burn wounds (B) and on post-admission days 7 (C) and 14 (D).

RESULTS

Thrombin generation assay showed a procoagulatory state: there was an increase in the velocity of thrombin generation (increase in time to peak of +13%, increase in velocity index of +22%), and peak amount of thrombin (+25%) between days A and B. All parameters reached their highest levels on day C and returned towards normal on day D. Rotational thrombelastometry showed a hypercoagulable state with an increase in clot firmness and alpha angle. Conventional coagulation tests remained within reference values.

CONCLUSIONS

In the first two weeks following burn, both the thrombin generation assay and rotational thrombelastometry show a hypercoagulable state, while conventional coagulation tests remain normal.

Fibrinolysis in Living Donor Liver Transplantation Recipients Evaluated Using Thromboelastometry: Impact on Mortality

BACKGROUND

Inadequate hemostasis during living donor liver transplantation (LDLT) is mainly due to coagulopathy but may also include fibrinolysis. The purpose of this study was to determine the incidence of fibrinolysis and assess its relevance to mortality in LDLT.

METHODS

The incidence and prognosis of fibrinolysis were retrospectively studied in 76 patients who underwent LDLT between April 2010 and February 2013. Fibrinolysis was evaluated and defined by maximum lysis (ML) >15% within a 60-minute run time using thromboelastometry (ROTEM).

RESULTS

Fibrinolysis was observed in 19 of the 76 (25%) patients before the anhepatic (pre-anhepatic) phase and was developed in 24 (32%) patients during and after the anhepatic (post-anhepatic) phase. In these 43 patients who had fibrinolysis, spontaneous recovery occurred in 29 patients (73%) within 3 hours after reperfusion of the liver graft. Recovery with tranexamic acid was noted in 2 patients with fibrinolysis in the post-anhepatic phase. Thrombosis in the portal vein and liver artery was noted in 14 patients, and the incidence was significantly greater in patients with post-anhepatic fibrinolysis than in those with pre-anhepatic fibrinolysis (P = .0017). Fibrinolysis that developed in the pre-anhepatic phase was associated with increased 30-day and 6-month mortalities (P = .0003 and .0026, respectively).

CONCLUSIONS

Fibrinolysis existed and developed in a large percentage of patients during LDLT. Thrombosis in the portal vein and hepatic artery was more common in patients with fibrinolysis in the post-anhepatic phase. Fibrinolysis that developed in the pre-anhepatic phase was associated with increased 30-day and 6-month mortalities.

K time & maximum amplitude of thromboelastogram predict post-central venous cannulation bleeding in patients with cirrhosis: A pilot study

Background & objectives:

Coagulation and haemostasis are dynamic processes. The haemostatic changes in liver disease affect all aspects of coagulation. The prothrombin time (PT)/international normalized ratio (INR) was developed to monitor oral anticoagulant therapy and the activated partial thromboplastin time to investigate inheritable single factor deficiencies. Viscoelastic tests such as thromboelastogram (TEG) give information about dynamics of clot formation (coagulation factor and anticoagulant activity), clot strength (platelets and fibrinogen) and clot stability (finbrinolysis and factor XIII). Administration of blood products before invasive procedures is still guided by INR and platelet count in patients of liver disease. This study was aimed to evaluate the validity of TEG to predict post-procedural bleed after central venous cannulation in patients with cirrhosis.

Methods:

Ninety patients aged 20-70 yr diagnosed with liver cirrhosis requiring elective central venous catheter (CVC) insertion were studied. Platelet count, INR, serum creatinine, TEG and Child-Turcotte-Pugh (CTP) score were recorded before the procedure. Right-sided internal jugular vein was cannulated. On the basis of presence or absence of post-procedural bleed, patients were divided into bleeding and non-bleeding groups. The CTP score, component of TEG (R - reaction time, K - coagulation time, MA - maximum amplitude and α - angle) and laboratory parameters of both the groups were compared.

Results:

Bleeding was seen more when CTP scores were ≥10 (P=0.05). The K time of 3.05 min or more on thromboelastograph was a significant predictor of bleeding [area under the curve (AUC) 0.694, P=0.047]. MA of 48.8 mm or more was a significant predictor of non-bleeding. INR ≥2.6 was a significant predictor of bleeding (AUC 0.765, P=0.005). K time had a low-positive predictive value of 20 per cent and the positive and negative likelihood ratios of 1.87 and 0.48, respectively.

Interpretation & conclusions:

Our results show that the cut-off value for INR ≥2.6 and K time ≥3.05 min predict bleeding and MA ≥48.8 mm predicts non-bleeding in patients with cirrhosis undergoing central venous pressure catheter cannulation.

Anesthesia for Liver Transplantation

The provision of anesthesia for a liver transplant program requires a dedicated team of anesthesiologists. Liver transplant anesthesiologists must have an understanding of liver physiology and anatomy; the spectrum of clinical disease associated with liver dysfunction; the impact of warm and cold ischemia times, surgical techniques in liver transplantation, and the impact of ischemia-reperfusion syndrome; and optimal practices to protect the liver. The team must provide a 24-hour service, be actively involved in the selection committee process, and stay current with advances in the subspecialty.

Flow, Liver, Flow: A Retrospective Analysis of the Interplay of Liver Disease and Coagulopathy in Chronic Subdural Hematoma

BACKGROUND

Chronic subdural hematoma (cSDH) is a common neurosurgical ailment, particularly in elderly patients. A recent study uncovered an association between liver disease and recurrence in patients with cSDH. Here, we explored that relationship to identify recurrence predictors in at-risk patients.

OBJECTIVE

We hypothesized that the association between liver disease and recurrence was attributable to coagulopathy secondary to liver disease.

METHODS

We retrospectively reviewed all patients with cSDH treated with burr-hole drainage by 2 surgeons between 2007 and 2015. Comorbidities and laboratory findings for each patient were examined by Pearson χ² analysis or Mann-Whitney U tests.

RESULTS

We identified 261 cSDH in 215 patients. Patients were a mean age of 65.6 years, and 72% were male. Sixteen patients with cSDH required repeat surgery (6.1%). There were 123 coagulopathic patients (47.1%), and 14 with liver disease (5.4%), all of whom were coagulopathic (P < 0.001). Coagulopathic patients with liver disease were more likely to experience recurrence than patients with coagulopathy alone (relative risk = 4.09, P = 0.019). Patients with liver disease had significantly elevated prothrombin time (P = 0.013) and reduced platelet counts (P < 0.001). Platelets also were reduced in coagulopathic patients with liver disease, as compared with those with coagulopathy alone (P = 0.002). Thrombocytopenia remained significant in a multivariate analysis (P < 0.001).

CONCLUSIONS

Liver disease is significantly associated with the recurrence of cSDH. Although coagulopathy alone does not predict recurrence, patients with coagulopathy and liver disease are at greater risk for recurrence than those with coagulopathy alone. Liver disease effects are reflected in certain hematologic laboratory values.

Retrospective review of Prothrombinex use by SAAS MedSTAR

OBJECTIVE

The aim of this study was to review and describe the use of Prothrombinex by a physician-led retrieval service based remote from a hospital blood bank.

METHODS

This is a retrospective observational study. Patients to whom Prothrombinex was administered by the retrieval team were identified from the retrieval service patient database. The paper case cards of the identified patients were then manually reviewed and the data matched to patients in the state-wide electronic laboratory record.

RESULTS

Between 1 January 2010 and 30 November 2013 38 cases were identified. For 28 the indication was warfarinisation associated with life-threatening bleeding (most commonly intracranial or gastrointestinal tract). In the remaining 10 cases, Prothrombinex was used to treat coagulopathy associated with liver disease or massive haemorrhage. The median time saved by the retrieval team administering PTX-VF, rather than waiting to the receiving centre, was 120 min (interquartile range: 85-195 min). The median dose of PTX-VF administered was 23.25 IU/kg (interquartile range: 20-33 IU/kg). Paired international normalised ratios (INRs) were available for 33 of the 38 patients. In the warfarin group, all patients had an improvement in their INR and 21 of 25 had correction of their INR. In the non-warfarin group, the effect on INR was more variable.

CONCLUSION

Prothrombinex is a clinically useful product that can be relatively easily stored and used by retrieval services, even if they are based in isolation from a hospital blood bank. More research is required to look at the utility of Prothrombinex for non-warfarin-related bleeding in the pre-hospital and retrieval environment.

Thromboelastographic reference ranges for a cirrhotic patient population undergoing liver transplantation

AIM

To describe the thromboelastography (TEG) “reference” values within a population of liver transplant (LT) candidates that underline the differences from healthy patients.

METHODS

Between 2000 and 2013, 261 liver transplant patients with a model for end-stage liver disease (MELD) score between 15 and 40 were studied. In particular the adult patients (aged 18-70 years) underwent to a first LT with a MELD score between 15 and 40 were included, while all patients with acute liver failure, congenital bleeding disorders, and anticoagulant and/or antiplatelet drug use were excluded. In this population of cirrhotic patients, preoperative haematological and coagulation laboratory tests were collected, and the pretransplant thromboelastographic parameters were studied and compared with the parameters measured in a previously studied population of 40 healthy subjects. The basal TEG parameters analysed in the cirrhotic population of liver candidates were as follows: Reaction time (r), coagulation time (k), Angle-Rate of polymerization of clot (αAngle), Maximum strenght of clot (MA), Amplitudes of the TEG tracing at 30 min and 60 min after MA is measured (A30 and A60), and Fibrinolysis at 30 and 60 min after MA (Ly30 and Ly60). The possible correlation between the distribution of the reference range and the gender, age, MELD score (higher or lower than 20) and indications for transplantation (liver pathology) were also investigated. In particular, a MELD cut-off value of 20 was chosen to verify the possible correlation between the thromboelastographic reference range and MELD score.

RESULTS

Most of the TEG reference values from patients with end-stage liver disease were significantly different from those measured in the healthy population and were outside the suggested normal ranges in up to 79.3% of subjects. Wide differences were found among all TEG variables, including r (41.5% of the values), k (48.6%), α (43.7%), MA (79.3%), A30 (74.4%) and A60 (80.9%), indicating a prevailing trend to hypocoagulability. The differences between the mean TEG values obtained from healthy subjects and the cirrhotic population were statistically significant for r (P = 0.039), k (P < 0.001), MA (P < 0.001), A30 (P < 0.001), A60 (P < 0.001) and Ly60 (P = 0.038), indicating slower and less stable clot formation in the cirrhotic patients. In the cirrhotic population, 9.5% of patients had an r value shorter than normal, indicating a tendency for faster clot formation. Within the cirrhotic patient population, gender, age and the presence of hepatocellular carcinoma or alcoholic cirrhosis were not significantly associated with greater clot firmness or enhanced whole blood clot formation, whereas greater clot strength was associated with a MELD score < 20, hepatitis C virus and cholestatic-related cirrhosis (P < 0.001; P = 0.013; P < 0.001).

CONCLUSION

The range and distribution of TEG values in cirrhotic patients differ from those of healthy subjects, suggesting that a specific thromboelastographic reference range is required for liver transplant candidates.

Comparison of Fresh-Frozen Plasma, Four-Factor Prothrombin Complex Concentrates, and Recombinant Factor VIIa to Facilitate Procedures in Critically Ill Patients with Coagulopathy from Liver Disease: A Retrospective Cohort Study

STUDY OBJECTIVE

To evaluate fresh-frozen plasma (FFP), four-factor prothrombin complex concentrates (PCCs), and recombinant factor VIIa (rFVIIa) for lowering international normalized ratio (INR) and facilitating procedures in critically ill patients with hepatic impairment.

DESIGN

Retrospective cohort study.

SETTING

Intensive care units at a large university-affiliated teaching hospital.

PATIENTS

Forty-five adults with hepatic impairment who were admitted between September 1, 2011, and December 31, 2015, and had an admission INR of 1.5 or greater, required an invasive intervention or minor surgical procedure, and received FFP alone (15 patients), PCCs (15 patients), or rFVIIa (15 patients).

MEASUREMENTS AND MAIN RESULTS

The primary outcomes were rates of achieving an INR less than 1.5 at the time of the procedure and an absolute change in INR from 12 hours before the procedure to the time of the procedure. Secondary outcomes were the time to the procedure, blood product use, bleeding rates, and adverse events. The mean ± SD doses of FFP, PCCs, and rFVIIa were 1.1 ± 0.5 units, 2523 ± 861 units, and 2.6 ± 0.9 mg, respectively, administered 2.1 ± 1.4 hours (p<0.05, FFP vs PCCs or rFVIIa), 1.3 ± 0.5 hours, and 1.3 ± 0.6 hours before the procedure, respectively. Achieving an INR less than 1.5 was more likely to occur with PCCs (80%, p=0.03) and rFVIIa (87%, p=0.01) compared with FFP (27%). INR reduction was greater with PCCs (1.6 ± 0.9, p<0.05) and rFVIIa (1.8 ± 0.7, p<0.01) compared with FFP (0.5 ± 0.8). Use of blood products (FFP, cryoprecipitate, packed red blood cells, and platelets) was significantly greater in the FFP group both before and after the procedural intervention. Hypervolemia was less likely to occur in the PCCs (40%, p=0.02) or rFVIIa (33%, p<0.01) groups than in the FFP group (93%). Overall, 33 (73%) of the 45 patients experienced minor bleeding. Three patients (7%) experienced clotting of a central line or dialysis filter, and all were in the PCCs or rFVIIa groups.

CONCLUSION

Unlike FFP, PCCs and rFVIIa effectively and safely reduced INR in critically ill patients with coagulopathy associated with liver impairment to expedite interventions. The amount of blood products used was significantly lower in the PCC and rFVIIa groups, possibly reducing the risk of hypervolemia. Bleeding rates, however, were similar across groups.

Monitoring and Treatment of Coagulation Disorders in End-Stage Liver Disease

BACKGROUND

Patients with end-stage liver disease (ESLD) are assumed to be at high risk of bleeding when undergoing any kind of invasive intervention (any kind of operation, including transplantation or minimally invasive interventions). Both bleeding and thrombosis are associated with a poor outcome.

METHODS

A selective literature research was conducted with the following key words: 'cirrhosis', 'coagulation', 'bleeding', 'INR' (international normalized ratio), 'aPTT' (activated partial thromboplastin time), and 'thrombocytopenia'. PubMed was used as the basic database.

RESULTS

Pathological values of standard laboratory tests (SLT) and thrombocytopenia have traditionally been regarded as indicators of a high risk for bleeding in all patients, and especially in those with ESLD. However, this approach has been challenged in recent years. The conventional approach in assessing a bleeding risk was based on pathological values of SLT. A 1.5-fold increase of INR or aPTT or platelets < 50/nl is assumed as pathological. The traditional approach of reducing the risk of excessive bleeding during an invasive procedure was to transfuse fresh frozen plasma (FFP) or platelet concentrates in order to improve hemostasis and to avoid bleeding complications. In the recent 20 years, several studies have provided us with a basis for questioning this approach. Their results indicated that SLT were not able to predict hypocoagulation and bleeding complications. Moreover, transfusion of various blood products has been associated with an increased risk for acute lung injury, transfusion-associated circulation overload, bacterial infections, and modulation of the immune system with increased numbers of nosocomial infections. Furthermore, a high volume overload, which is required to correct a hemostasis disorder if FFP are being used in ESLD patients, may increase portal venous pressure. This might significantly increase bleeding in these ESLD patients. Although the first publication about the successful use of a viscoelastic test (VET) in liver transplantation dates back to 1985, physicians are still very reluctant to use VETs (Thrombelastography™ and/or ROTEM™) for the perioperative optimization of hemostasis. However, some very recent studies demonstrated that the use of VETs for assessing the risk of bleeding avoids futile transfusion with a similar safety profile. The implementation of ROTEM-based coagulation management and the use of coagulation factors (prothrombin complex, fibrinogen concentrate) have led to a highly significant reduction of FFP and red blood cell transfusions, without an increased incidence of thrombosis or bleeding.

CONCLUSION

Patients with ESLD often show pathological values of conventional parameters used to analyze coagulation hemostasis. Without overt signs of excessive bleeding, however, they do not require coagulation treatment. The use of FFP, which is associated with fluid overload and increase in portal venous pressure, should be avoided. The preferable coagulation treatment should be based on VET-guided administration of coagulation factor concentrates.

Blood Products

Perioperative hemorrhage, anemia, thrombocytopenia, and coagulopathy are common in the surgical intensive care unit. As a result, blood product transfusion occurs frequently. While red blood cell, plasma, and platelet transfusions have a lifesaving role in the resuscitation of patients with trauma and hemorrhagic shock, their application in other settings is under scrutiny. Current data would suggest a conservative approach be taken, thus avoiding unnecessary transfusion and associated potential adverse events. New and developmental products such as prothrombin complex concentrates offer appealing alternatives to traditional transfusion practice—potentially with fewer risks—however, further investigation into their safety and efficacy is required before practice change can take place.

Acute-on-chronic liver failure: Pathogenesis, prognostic factors and management

Acute-on-chronic liver failure (ACLF) is increasingly recognized as a complex syndrome that is reversible in many cases. It is characterized by an acute deterioration of liver function in the background of a pre-existing chronic liver disease often associated with a high short-term mortality rate. Organ failure (OF) is always associated, and plays a key role in determining the course, and the outcome of the disease. The definition of ACLF remains controversial due to its overall ambiguity, with several disparate criteria among various associations dedicated to the study of liver diseases. Although the precise pathogenesis needs to be clarified, it appears that an altered host response to injury might be a contributing factor caused by immune dysfunction, ultimately leading to a pro-inflammatory status, and eventually to OF. The PIRO concept (Predisposition, Insult, Response and Organ Failure) has been proposed to better approach the underlying mechanisms. It is accepted that ACLF is a different and specific form of liver failure, where a precipitating event is always involved, even though it cannot always be ascertained. According to several studies, infections and active alcoholism often trigger ACLF. Viral hepatitis, gastrointestinal haemorrhage, or drug induced liver injury, which can also provoke the syndrome. This review mainly focuses on the physiopathology and prognostic aspects. We believe these features are essential to further understanding and providing the rationale for improveddisease management strategies.

Preoperative Thromboelastometry as a Predictor of Transfusion Requirements during Adult Living Donor Liver Transplantation

BACKGROUND

The ability to predict transfusion requirements may improve perioperative bleeding management as an integral part of a patient blood management program. Therefore, the aim of our study was to evaluate preoperative thromboelastometry as a predictor of transfusion requirements for adult living donor liver transplant recipients.

METHODS

The correlation between preoperative thromboelastometry variables in 100 adult living donor liver transplant recipients and intraoperative blood transfusion requirements was examined by univariate and multivariate linear regression analysis. Thresholds of thromboelastometric parameters for prediction of packed red blood cells (PRBCs), fresh frozen plasma (FFP), platelets, and cryoprecipitate transfusion requirements were determined with receiver operating characteristics analysis. The attending anesthetists were blinded to the preoperative thromboelastometric analysis. However, a thromboelastometry-guided transfusion algorithm with predefined trigger values was used intraoperatively. The transfusion triggers in this algorithm did not change during the study period.

RESULTS

Univariate analysis confirmed significant correlations between PRBCs, FFP, platelets or cryoprecipitate transfusion requirements and most thromboelastometric variables. Backward stepwise logistic regression indicated that EXTEM coagulation time (CT), maximum clot firmness (MCF) and INTEM CT, clot formation time (CFT) and MCF are independent predictors for PRBC transfusion. EXTEM CT, CFT and FIBTEM MCF are independent predictors for FFP transfusion. Only EXTEM and INTEM MCF were independent predictors of platelet transfusion. EXTEM CFT and MCF, INTEM CT, CFT and MCF as well as FIBTEM MCF are independent predictors for cryoprecipitate transfusion. Thromboelastometry-based regression equation accounted for 63% of PRBC, 83% of FFP, 61% of cryoprecipitate, and 44% of platelet transfusion requirements.

CONCLUSION

Preoperative thromboelastometric analysis is helpful to predict transfusion requirements in adult living donor liver transplant recipients. This may allow for better preparation and less cross-matching prior to surgery. The findings of our study need to be re-validated in a second prospective patient population.

Cirrhosis patients have a coagulopathy that is associated with decreased clot formation capacity

BACKGROUND

The coagulopathy in cirrhosis is associated with thrombosis and bleeding.

OBJECTIVES

To gain better insights into the coagulopathy in patients with cirrhosis, we evaluated plasma thrombin generation and whole blood clot formation in a cross-sectional study.

METHODS

Blood was collected from 73 patients with all-cause cirrhosis (Child-Pugh-A n = 52, B n = 15, C n = 6) and 20 healthy controls. Activity of the coagulation pathways was measured with assays for factor (F) VIIa and FIXa-antithrombin and FXa-antithrombin complexes, respectively. Thrombin generation by calibrated automated thrombography was determined in platelet-poor plasma using a 1 or 5 pm tissue factor trigger with/without thrombomodulin. ROTEM measurements were performed in whole blood triggered with 35 pm tissue factor without/with 175 ng mL(-1) tissue plasminogen activator (the latter refered to as 'tPA-ROTEM').

RESULTS

We observed an increased generation of FVIIa and a moderately elevated amount of FIXa (in complex with antithrombin) without apparent increase in FX activation in patients with cirrhosis. In accordance with this prothrombotic state, markers of thrombin generation potential were also increased upon increasing severity of cirrhosis. In the whole blood clotting assay we observed delayed clot formation and decreased clot strength associated with increased severity of cirrhosis. No significant differences were found for tPA-ROTEM parameters of clot degradation.

CONCLUSION

These results indicate that cirrhosis patients have an overall procoagulant plasma milieu but a decreased whole blood clot formation capacity with an apparently unaltered resistance to clot lysis.