Thromboelastography-guided therapy improves patient blood management and certain clinical outcomes in elective cardiac and liver surgery and emergency resuscitation: A systematic review and analysis

Viscoelastic haemostatic assays to guide therapy in elective surgery: an updated systematic review and meta-analysis

BACKGROUND

Patients undergoing major surgery frequently experience major uncontrolled bleeding. The aim of this systematic review and meta-analysis was to evaluate the clinical efficacy of using viscoelastic haemostatic assays to manage peri-operative bleeding in elective surgery.

METHODS

We searched PubMed/MEDLINE and Embase databases for randomised controlled trials according to pre-determined criteria. The primary outcomes were blood product requirements; duration of stay in the operating theatre or ICU; and surgical reintervention rate.

RESULTS

We included 20 randomised controlled trials. The overall risk of bias was low to moderate. Twelve studies used thromboelastography-based transfusion algorithms, while eight used thromboelastometry. Viscoelastic haemostatic assay-guided therapy was associated with a statistically significant reduction in transfusion of red blood cells (standardised mean difference (95%CI) 0.16 (-0.29 to 0.02)), platelets (standardised mean difference (95%CI) -0.33 (-0.56 to -0.10)) and fresh frozen plasma (standardised mean difference (95%CI) -0.64 (-1.01 to -0.28)). There was no evidence of an effect of viscoelastic haemostatic assay-guided therapy on surgical reintervention (relative risk (95%CI) 1.09 (0.70-1.69)). Viscoelastic haemostatic assay-guided therapy was associated with lower blood loss and shorter ICU duration of stay. There was no evidence of any effect on total duration of stay and all-cause mortality.

CONCLUSIONS

Viscoelastic haemostatic assay-guided therapy may reduce peri-operative blood product transfusion requirements and blood loss during major elective surgery, with no discernible effect on patient-centred outcomes. The overall quality of evidence was modest.

TEG-Guided Anticoagulation Assessment in Deep Vein Arterialization: A Prospective Analysis

INTRODUCTION

Deep Vein Arterialization (DVA) is an innovative surgical technique aimed at enhancing blood flow in compromised limbs facing amputation. Maintenance of flow post-revascularization is crucial to limb salvage. As this is a new technique, no standardized thromboprophylaxis regime is currently established, and post-procedure thromboprophylaxis is at the discretion of the proceduralist.

OBJECTIVE

This study aims to evaluate coagulation profiles using viscoelastic studies in peripheral artery disease (PAD) patients who underwent DVA, assessing the impact of various post-procedure thromboprophylaxis regimens.

METHODS

Patients (age >60years) undergoing DVA were prospectively evaluated using thromboelastography at baseline, 1, 3, and 6 months (2020-2024). Post-procedure thromboprophylaxis included monotherapy antiplatelet (MAPT), MAPT + direct oral anticoagulant (DOAC), dual antiplatelet therapy (DAPT), or DAPT + DOAC. Coagulation profiles were analyzed using descriptive statistics.

RESULTS

Among sixteen patients (mean age 66.6 years, 75% male/Caucasian), hypertension and hyperlipidemia were present in 91%, and diabetes in 88%. The DAPT + DOAC group showed consistently superior platelet inhibition with the lowest ADP MA values throughout: baseline (35.65 mm vs. 42.2-65.03 mm in other groups), 1 month (26.7 mm vs. 32.14-69.4 mm), 3 months (27.36 mm vs. 32.2-39.97 mm), and 6 months (43.7 mm vs. 50.2-50.5 mm). MAPT demonstrated the slowest clot strengthening (CK angle 65.25° vs. 68.7-71.55°).

CONCLUSION

TEG-PM demonstrated enhanced platelet inhibition and reduced clot formation in the DAPT + DOAC group, suggesting the importance of coagulation monitoring.

TEG® 6s coagulation testing with a novel heparin neutralization cartridge: Technical validation and determination of normal reference ranges

OBJECTIVES

We sought to establish normal reference ranges (NRRs) for a novel TEG 6s cartridge (TEG 6s Citrated: K, KH, RTH, FFH [Global Hemostasis]) (Haemonetics Corporation, Boston, MA, US).

METHODS

Healthy volunteers (≥18 years of age) included in this single-arm study provided single samples of whole blood. Primary end points included TEG parameters in the citrated kaolin (CK), CK with heparinase (CKH), RapidTEG with heparinase (CRTH), and functional fibrinogen with heparinase (CFFH) assays.

RESULTS

Evaluable data were contributed by 164 volunteers (48.8% female; 62% White/Caucasian). The following NRRs were established: CK maximum amplitude (MA), 51.0 to 67.6 mm; CKH-MA, 51.8 to 67.9 mm; CRTH-MA, 53.0 to 68.9 mm; CFFH-MA, 15.3 to 34.4 mm; CK reaction time, 5.0 to 9.1 minutes; CKH reaction time, 4.9 to 9.4 minutes; CKH lysis 30 minutes after MA, 0% to 3.2%. Duplicate measurements demonstrated high reproducibility. CFFH-MA correlated with Clauss fibrinogen concentration (Pearson correlation coefficient, 0.74). Laboratory-based studies demonstrated maintenance of the relationship between CFFH-MA and fibrinogen up to 1344 mg/dL (hyperfibrinogenemic samples) and acceptability of heparin neutralization up to concentrations of low molecular weight and unfractionated heparin of 1.3 IU/mL and 5 IU/mL, respectively.

CONCLUSIONS

This study established NRRs for the Global Hemostasis cartridge and serves as a proof of concept for the validity of results obtained using this cartridge.

Breaking barriers in trauma research: A narrative review of opportunities to leverage veterinary trauma for accelerated translation to clinical solutions for pets and people

Trauma is a common cause of morbidity and mortality in humans and companion animals. Recent efforts in procedural development, training, quality systems, data collection, and research have positively impacted patient outcomes; however, significant unmet need still exists. Coordinated efforts by collaborative, translational, multidisciplinary teams to advance trauma care and improve outcomes have the potential to benefit both human and veterinary patient populations. Strategic use of veterinary clinical trials informed by expertise along the research spectrum (i.e., benchtop discovery, applied science and engineering, large laboratory animal models, clinical veterinary studies, and human randomized trials) can lead to increased therapeutic options for animals while accelerating and enhancing translation by providing early data to reduce the cost and the risk of failed human clinical trials. Active topics of collaboration across the translational continuum include advancements in resuscitation (including austere environments), acute traumatic coagulopathy, trauma-induced coagulopathy, traumatic brain injury, systems biology, and trauma immunology. Mechanisms to improve funding and support innovative team science approaches to current problems in trauma care can accelerate needed, sustainable, and impactful progress in the field. This review article summarizes our current understanding of veterinary and human trauma, thereby identifying knowledge gaps and opportunities for collaborative, translational research to improve multispecies outcomes. This translational trauma group of MDs, PhDs, and DVMs posit that a common understanding of injury patterns and resulting cellular dysregulation in humans and companion animals has the potential to accelerate translation of research findings into clinical solutions.

Does an early, balanced resuscitation strategy reduce the incidence of hypofibrinogenemia in hemorrhagic shock?

Objectives

Some centers have recommended including concentrated fibrinogen replacement in massive transfusion protocols (MTPs). Given our center's policy of aggressive early balanced resuscitation (1:1:1), beginning prehospital, we hypothesized that our rates of hypofibrinogenemia may be lower than those previously reported.

Methods

In this retrospective cohort study, patients presenting to our trauma center November 2017 to April 2021 were reviewed. Patients were defined as hypofibrinogenemic (HYPOFIB) if admission fibrinogen <150 or rapid thrombelastography angle <60. Univariate and multivariable analyses assessed risk factors for HYPOFIB. Inverse probability of treatment weighting analyses assessed the relationship between cryoprecipitate administration and outcomes.

Results

Of 29 782 patients, 6618 level 1 activations, and 1948 patients receiving emergency release blood, <1%, 2%, and 7% were HYPOFIB. HYPOFIB patients were younger, had higher head Abbreviated Injury Scale value, and had worse coagulopathy and shock. HYPOFIB had lower survival (48% vs 82%, p<0.001), shorter time to death (median 28 (7, 50) vs 36 (14, 140) hours, p=0.012), and were more likely to die from head injury (72% vs 51%, p<0.001). Risk factors for HYPOFIB included increased age (OR (95% CI) 0.98 (0.96 to 0.99), p=0.03), head injury severity (OR 1.24 (1.06 to 1.46), p=0.009), lower arrival pH (OR 0.01 (0.001 to 0.20), p=0.002), and elevated prehospital red blood cell to platelet ratio (OR 1.20 (1.02 to 1.41), p=0.03). Among HYPOFIB patients, there was no difference in survival for those that received early cryoprecipitate (within 2 hours; 40 vs 47%; p=0.630). On inverse probability of treatment weighted analysis, early cryoprecipitate did not benefit the full cohort (OR 0.52 (0.43 to 0.65), p<0.001), nor the HYPOFIB subgroup (0.28 (0.20 to 0.39), p<0.001).

Conclusions

Low rates of hypofibrinogenemia were found in our center which treats hemorrhage with early, balanced resuscitation. Previously reported higher rates may be partially due to unbalanced resuscitation and/or delay in resuscitation initiation. Routine empiric inclusion of concentrated fibrinogen replacement in MTPs is not supported by the currently available data.

Level of evidence

Level III.

Extract from the 2022 ESC Guidelines on cardiovascular assessment and management of patients undergoing non-cardiac surgery - Patient Blood Management

The 2022 Guidelines on cardiovascular assessment and management of patients undergoing non-cardiac surgery of the European Society of Cardiology are an update on the previous guidelines reported in 2014. The revised guidelines provide standardized perioperative cardiovascular management of surgical patients and emphasis on risk assessment of the patient combined with the inherent risk of the surgical procedure. One of the novelties in these guidelines is the Patient Blood Management programme, which is based on a three pillar concept: preoperative hemoglobin optimization, minimize iatrogenic blood loss and bleeding, and harness tolerance to anemia in an effort to improve patient outcome. In this review, we highlight the three pillars of Patient Blood Management and recommendations made by the 2022 ESC Guidelines on cardiovascular assessment and management of patients undergoing non-cardiac surgery.

Application of thromboelastography to predict the severity of bleeding after chimeric antigen receptor (CAR)-T cell therapy in patients with hematological malignancy

OBJECTIVES

We aim to analyze the predictive value of thromboelastography on bleeding severity of patients with chimeric antigen receptor (CAR)-T cell therapy.

METHODS

A total of 80 patients with refractory/relapsed hematological malignancy were enrolled and divided into two groups: the severe bleeding group and the non-severe bleeding group. The thromboelastography data was collected on the day of CAR-T infusion and the 3rd, 7th, 10th, 13th, 17th, and 20th day after CAR-T cell infusion.

RESULTS

The patients of the severe bleeding group had lower platelet (p < .007), maximum amplitude (p = .002), coagulation index (p = .005), and longer coagulation time (p = .019). Increasing trend in reaction time and coagulation time and decreasing trend in Alpha, maximum amplitude, and coagulation index on Days 0-10, opposite on Days 10-20. Univariate logistic regression analysis and multivariable logistic regression analysis showed maximum amplitude on the 3rd day after CAR-T cell infusion (MA3) (OR = 0.9; 95% CI = 0.84-0.95; p < .001) and cytokine release syndrome grade (OR = 2.57; 95% CI = 1.35-5.32; p = .006) were significantly associated with high bleeding severity.

CONCLUSIONS

Thromboelastography was considered to be a good predictor of bleeding severity.

Patient blood management in major digestive surgery: Recommendations from the Italian multisociety (ACOI, SIAARTI, SIdEM, and SIMTI) modified Delphi consensus conference

Patient blood management (PBM) is defined as the timely application of evidence-based medical and surgical concepts designed to maintain a surgical patient’s hemoglobin concentration, optimize hemostasis, and minimize blood loss in an effort to improve the outcomes. PBM is able to reduce mortality up to 68%, reoperation up to 43%, readmission up to 43%, composite morbidity up to 41%, infection rate up to 80%, average length of stay by 16%–33%, transfusion from 10% to 95%, and costs from 10% to 84% after major surgery. It should be noticed, however, that the process of PBM implementation is still in its infancy, and that its potential to improve perioperative outcomes could be strictly linked to the degree of adherence/compliance to the whole program, with decoupling and noncompliance being significant factors for failure. Therefore, the steering committees of four major Italian scientific societies, representing general surgeons, anesthesiologists and transfusion medicine specialists (Associazione Chirurghi Ospedalieri Italiani; Società Italiana di Anestesia, Analgesia, Rianimazione e Terapia Intensiva; Società Italiana di Emaferesi e Manipolazione Cellulare; Società Italiana di Medicina Trasfusionale e Immunoematologia), organized a joint modified Delphi consensus conference on PBM in the field of major digestive surgery (upper and lower gastrointestinal tract, and hepato-biliopancreatic resections), whose results and recommendations are herein presented.

Thromboelastography-Guided Correction of Coagulopathy Before Tunneled Central Venous Access in Critically Ill Patients With Liver Disease: A Propensity Score-Matched Study

Importance

Optimal blood product transfusion strategies before tunneled central venous catheter (CVC) placement are required in critically ill coagulopathic patients with liver disease to reduce exposure to allogeneic blood products and mitigate bleeding and thrombotic complications.

Objectives

This study evaluated the safety and efficacy of a thromboelastography-guided transfusion strategy for the correction of coagulopathy in patients with liver disease compared with a conventional transfusion strategy (using international normalized ratio, platelet count, and fibrinogen) before tunneled CVC insertion.

Design Setting and Participants

A retrospective propensity score-matched single-center cohort study was conducted at a quaternary care academic medical center involving 364 patients with liver disease (cirrhosis and acute liver failure) who underwent tunneled CVC insertion in the ICU. Patients were stratified into two groups based on whether they received blood product transfusions based on a thromboelastography-guided or conventional transfusion strategy.

Main Outcomes and Measures

Primary outcomes that were evaluated included the volume, units and cost of blood products (fresh frozen plasma, cryoprecipitate, and platelets) when using a thromboelastography-guided or conventional approach to blood transfusions. Secondary outcomes included the frequency of procedure-related bleeding and thrombotic complications.

Results

The total number of units/volume/cost of fresh frozen plasma (12 U/3,000 mL/$684 vs. 32 U/7,500 mL/$1,824 [p = 0.019]), cryoprecipitate (60 U/1,500 mL/$3,240 vs. 250 U/6,250 mL/$13,500 [p < 0.001]), and platelets (5 U/1,500 mL/$2,610 vs. 13 units/3,900 mL/$6,786 [p = 0.046]) transfused were significantly lower in the thromboelastography-guided transfusion group than in the conventional transfusion group. No differences in the frequency of bleeding/thrombotic events were observed between the two groups.

Conclusions and Relevance

A thromboelastography-guided transfusion strategy for correction of coagulopathy in critically ill patients with liver disease before tunneled CVC insertion, compared with a conventional transfusion strategy, reduces unnecessary exposure to allogeneic blood products and associated costs without increasing the risk for peri-procedural bleeding and thrombotic complications.

A Review of Thromboelastography for Nurses

BACKGROUND

Thromboelastography is a viscoelastic test with multiple potential advantages over conventional coagulation tests in various disease states. Thromboelastography rapidly provides qualitative and quantitative information related to a patient's coagulation status.

OBJECTIVE

To describe recent studies of the use of thromboelastography in various clinical states and how thromboelastography is used in coagulation management.

METHODS

A literature review using the MEDLINE and PubMed databases was conducted. The updated methodology for integrated reviews by Whittemore and Knafl was followed. Coauthors evaluated separate areas that were independently reviewed by other coauthors to ensure appropriateness for inclusion.

RESULTS

The use of thromboelastography for various clinical conditions with challenging hemostatic profiles has increased. This integrative review covers the use of thromboelastography in patients with trauma, medication-induced coagulopathy, acute and chronic liver failure, and cardiothoracic surgery. Potential future directions are also discussed.

DISCUSSION

Thromboelastography has numerous potential benefits over conventional coagulation tests for assessing coagulation status in patients in various clinical states. Nurses can support clinical decisions to use the most appropriate test for their patients.

CONCLUSIONS

Each team member should be involved in assessing the usefulness of thromboelastography. Critical care nurses and the multidisciplinary team must identify patients in whom its use is warranted, interpret the results, and provide appropriate interventions in response to the results and clinical status of the patient.

Coagulation Tests and Bleeding Classification After Cardiopulmonary Bypass: A Prospective Study

OBJECTIVE

No recent prospective studies have analyzed the accuracy of standard coagulation tests and thromboelastography (TEG) to identify patients with excessive microvascular bleeding following cardiopulmonary bypass (CPB). The aim of this study was to assess the value of coagulation profile tests, as well as TEG, for the classification of microvascular bleeding after CPB.

DESIGN

A prospective observational study.

SETTING

At a single-center academic hospital.

PARTICIPANTS

Patients ≥18 years of age undergoing elective cardiac surgery.

INTERVENTIONS

Qualitative assessment of microvascular bleeding post-CPB (surgeon and anesthesiologist consensus) and the association with coagulation profile tests and TEG values.

MEASUREMENTS AND MAIN RESULTS

A total of 816 patients were included in the study-358 (44%) bleeders and 458 (56%) nonbleeders. Accuracy, sensitivity, and specificity for the coagulation profile tests and TEG values ranged from 45% to 72%. The predictive utility was similar across tests, with prothrombin time (PT) (62% accuracy, 51% sensitivity, 70% specificity), international normalized ratio (INR) (62% accuracy, 48% sensitivity, 72% specificity), and platelet count (62% accuracy, 62% sensitivity, 61% specificity) displaying the highest performance. Secondary outcomes were worse in bleeders versus nonbleeders, including higher chest tube drainage, total blood loss, transfusion of red blood cells, reoperation rates (p < 0.001, respectively), readmission within 30 days (p = 0.007), and hospital mortality (p = 0.021).

CONCLUSIONS

Standard coagulation tests and individual components of TEG in isolation agree poorly with the visual classification of microvascular bleeding after CPB. The PT-INR and platelet count performed best but had low accuracy. Further work is warranted to identify better testing strategies to guide perioperative transfusion decisions in cardiac surgical patients.

Thromboelastometry-guided haemostatic resuscitation in severely injured patients: a propensity score-matched study

BACKGROUND

To accelerate the diagnosis and treatment of trauma-induced coagulopathy (TIC), viscoelastic haemostatic assays (VHA) are increasingly used worldwide, although their value is still debated, with a recent randomised trial showing no improvement in outcome. The objective of this retrospective study was to compare 2 cohorts of injured patients in which TIC was managed with either a VHA-based algorithm or a conventional coagulation test (CCT)-based algorithm.

METHODS

Data were retrieved from 2 registries and patients were included in the study if they received at least 1 unit of red blood cell in the first 24 h after admission. A propensity score, including sex, age, blunt vs. penetrating, systolic blood pressure, GCS, ISS and head AIS, admission lactate and PT_ratio, tranexamic acid administration, was then constructed. Primary outcome was the proportion of subjects who were alive and free of massive transfusion (MT) at 24 h after injury. We also compared the cost for blood products and coagulation factors.

RESULTS

From 2012 to 2019, 7250 patients were admitted in the 2 trauma centres, and among these 624 were included in the study (CCT group: 380; VHA group: 244). After propensity score matching, 215 patients remained in each study group without any significant difference in demographics, vital signs, injury severity, or laboratory analysis. At 24 h, more patients were alive and free of MT in the VHA group (162 patients, 75%) as compared to the CCT group (112 patients, 52%; p < 0.01) and fewer patients received MT (32 patients, 15% vs. 91 patients, 42%, p < 0.01). However, no significant difference was observed for mortality at 24 h (odds ratio 0.94, 95% CI 0.59-1.51) or survival at day 28 (odds ratio 0.87, 95% CI 0.58-1.29). Overall cost of blood products and coagulation factors was dramatically reduced in the VHA group as compared to the CCT group (median [interquartile range]: 2357 euros [1108-5020] vs. 4092 euros [2510-5916], p < 0.001).

CONCLUSIONS

A VHA-based strategy was associated with an increase of the number of patients alive and free of MT at 24 h together with an important reduction of blood product use and associated costs. However, that did not translate into an improvement in mortality.

Risk Factors for Hypocoagulability After Cardiac Surgery: A Retrospective Study

Hemostatic disturbances after cardiac surgery can lead to excessive postoperative bleeding. Thromboelastography (TEG) was employed to evaluate perioperative coagulative alterations in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB), investigating the correlation between factors concomitant with cardiac surgery and modifications in coagulation. Coagulation index as determined by TEG correlated significantly with postoperative bleeding at 24-72 h after cardiac surgery (P < .001). Among patients with a normal preoperative coagulation index, those with postoperative hypocoagulability showed significantly lower nadir temperature (P  =  .003), larger infused fluid volume (P  =  .003), and longer CPB duration (P  =  .033) than those with normal coagulation index. Multivariate logistic regression showed that nadir intraoperative temperature was an independent predictor of postoperative hypocoagulability (adjusted OR: 0.772, 95% CI: 0.624-0.954, P  =  .017). Multivariate linear regression demonstrated linear associations of nadir intraoperative temperature (P  =  .017) and infused fluid volume (P  =  .005) with change in coagulation index as a result of cardiac surgery. Patients are susceptible to hypocoagulability after cardiac surgery, which can lead to increased postoperative bleeding. Ensuring appropriate temperature and fluid volume during cardiac surgery involving CPB may reduce risk of postoperative hypocoagulability and bleeding.

The importance of liver function assessment before cardiac surgery: A narrative review

The demand for cardiac surgery procedures is increasing globally. Thanks to an improvement in survival driven by medical advances, patients with liver disease undergo cardiac surgery more often. Liver disease is associated with the development of heart failure, especially in patients with advanced cirrhosis. Cardiovascular risk factors can also contribute to the development of both cardiomyopathy and liver disease and heart failure itself can worsen liver function. Despite the risk that liver disease and cirrhosis represent for the perioperative management of patients who undergo cardiac surgery, liver function is often not included in common risk scores for preoperative evaluation. These patients have worse short and long-term survival when compared with other cardiac surgery populations. Preoperative evaluation of liver function, postoperative management and close postoperative follow-up are crucial for avoiding complications and improving results. In the present narrative review, we discuss the pathophysiological components related with postoperative complications and mortality in patients with liver disease who undergo cardiac surgery and provide recommendations for the perioperative management.

Bloodless surgery in urologic oncology: A review of hematologic, anesthetic, and surgical considerations

The urologic oncology patient who refuses blood transfusion can present unique challenges in perioperative blood management. Since blood loss and associated transfusion can be expected in many complex urologic oncology surgeries, a multidisciplinary approach may be required for optimal outcomes. Through collaboration with the hematologist, anesthesiologist, and urologist, various techniques can be employed in the perioperative phases to minimize blood loss and the need for transfusion. We review the risks and benefits of these techniques and offer recommendations specific to the urologic oncology patient.

Viscoelastic Testing Prior to Non-surgical Procedures Reduces Blood Product Use Without Increasing Bleeding Risk in Cirrhosis

BACKGROUND/AIMS

Thromboelastography (TEG) and Rotational Thromboelastometry (ROTEM) analyze hemostatic function in patients with coagulopathy. We sought to quantify the impact of TEG and ROTEM-guided transfusion algorithms on blood product utilization in patients with cirrhosis undergoing non-surgical procedures.

METHODS

We performed a systematic review and meta-analysis on the utility of viscoelastic testing prior to non-surgical procedures to determine their impact on pre-procedural blood product use and post-procedural bleeding events. Studies comparing TEG or ROTEM-guided transfusions with standard-of-care (SOC) prior to non-surgical procedures in adult patients with cirrhosis were included. Primary outcomes were fresh frozen plasma (FFP) and platelet transfusion and secondary outcomes of post-procedure bleeding, transfusion-related complications, and mortality; and were reported as standardized mean differences (SMD) and risk ratios (RR).

RESULTS

Six studies (five randomized controlled trials and one cohort study) involving 367 patients met inclusion criteria. Compared with SOC, TEG/ROTEM-guided transfusions led to an overall decreased number of patients who received FFP transfusions (SMD = -0.93, 95% CI [-1.54, -0.33], p < 0.001) and platelets transfusions (SMD = -1.50, CI [-1.85, -1.15], p < 0.001). Total amount of FFP (SMD-0.86, p < 0.001) and platelet (SMD = -0.99, p < 0.001) transfused in the TEG/ROTEM group were also lower. Decreased pre-procedure transfusion in the TEG/ROTEM group did not result in increased post-procedure bleeding (RR = 0.61, p = 0.09) or in mortality (RR = 0.91, p = 0.93).

CONCLUSION

In patients with cirrhosis, TEG or ROTEM significantly reduces blood product utilization prior to non-surgical procedures, with no increase in post-procedure bleeding or mortality. TEG and ROTEM utilization can promote high-value care and improve transfusion stewardship in this population.

Traumatized triad of complementopathy, endotheliopathy, and coagulopathy ˗ Impact on clinical outcomes in severe polytrauma patients

Complementopathy, endotheliopathy, and coagulopathy following a traumatic injury are key pathophysiological mechanisms potentially associated with multiple-organ failure (MOF) and mortality. However, the heterogeneity in the responses of complementopathy, endotheliopathy, and coagulopathy to trauma, the nature and extent of their interplay, and their relationship to clinical outcomes remain unclear. Fifty-four poly-trauma patients were enrolled and divided into three subgroups based on their ISS. Biomarkers in blood plasma reflecting complement activation, endothelial damage, and coagulopathy were measured starting from admission to the emergency department and at 3, 6, 12, 24, and 120 hours after admission. Comparative analyses showed that severely injured patients (ISS>24) were associated with longer days on mechanical ventilation, in the intensive care unit and hospital stays, and a higher incidence of hyperglycemia, bacteremia, respiratory failure and pneumonia compared to mildly (ISS<16) or moderately (ISS=16-24) injured patients. In this trauma cohort, complement was activated early, primarily through the alternative complement pathway. As measured in blood plasma, severely injured patients had significantly higher levels of complement activation products (C3a, C5a, C5b-9, and Bb), endothelial damage markers (syndecan-1, sTM, sVEGFr1, and hcDNA), and fibrinolytic markers (D-dimer and LY30) compared to less severely injured patients. Severely injured patients also had significantly lower thrombin generation (ETP and peak) and lower levels of coagulation factors (I, V, VIII, IX, protein C) than less severely injured patients. Complement activation correlated with endothelial damage and hypocoagulopathy. Logistic regression analyses revealed that Bb >1.57 μg/ml, syndecan-1 >66.6 ng/ml or D-dimer >6 mg/L at admission were associated with a higher risk of MOF/mortality. After adjusting for ISS, each increase of the triadic score defined above (Bb>1.57 µg/ml/Syndecan-1>66.6 ng/ml/D-dimer>6.0mg/L) was associated with a 6-fold higher in the odds ratio of MOF/death [OR: 6.83 (1.04-44.96, P=0.046], and a 4-fold greater in the odds of infectious complications [OR: 4.12 (1.04-16.36), P=0.044]. These findings provide preliminary evidence of two human injury response endotypes (traumatized triad and non-traumatized triad) that align with clinical trajectory, suggesting a potential endotype defined by a high triadic score. Patients with this endotype may be considered for timely intervention to create a pro-survival/organ-protective phenotype and improve clinical outcomes.

Thromboelastography-Guided Therapy Enhances Patient Blood Management in Cirrhotic Patients: A Meta-analysis Based on Randomized Controlled Trials

Patients with cirrhosis often have abnormal hemostasis, with increased risk of hemorrhage and thrombosis. Thromboelastography provides a rapid assessment of the coagulation status and can guide product transfusions in adult patients with cirrhosis. This study aimed to determine whether the use of thromboelastography in adult patients with cirrhosis decreases blood product use and impacts adverse events or mortality compared with standard practice. A registered (PROSPERO CRD42020192458) systematic review and meta-analysis was conducted for randomized controlled trials (RCTs) comparing thromboelastography-guided hemostatic management versus standard practice (control). Co-primary outcomes were the number of transfused platelet units and fresh frozen plasma (FFP) units. Secondary outcomes were mortality, adverse events, utilization of individual blood products, blood loss or excessive bleeding events, hospital/intensive care unit stay, and liver transplant/intervention outcomes. The search identified 260 articles, with five RCTs included in the meta-analysis. Platelet use was five times lower with thromboelastography versus the control, with a relative risk of 0.17 (95% confidence interval [CI]: [0.03–0.90]; p = 0.04), but FFP use did not differ significantly. Thromboelastography was associated with less blood product (p < 0.001), FFP + platelets (p < 0.001), and cryoprecipitate (p < 0.001) use. No differences were reported in bleeding rates or longer term mortality between groups, with the thromboelastography group having lower mortality at 7 days versus the control (relative risk [95% CI] = 0.52 [0.30–0.91]; p = 0.02). Thromboelastography-guided therapy in patients with cirrhosis enhances patient blood management by reducing use of blood products without increasing complications.

Role of Viscoelastic and Conventional Coagulation Tests for Management of Blood Product Replacement in the Bleeding Patient

An important aim of viscoelastic testing (VET) is to implement transfusion algorithms based on coagulation test results to help reduce transfusion rates and improve patient outcomes. Establishing a rapid diagnosis and providing timely treatment of coagulopathy is the cornerstone of management of severely bleeding patients in trauma, postpartum hemorrhage, and major surgery. As the nature of acute bleeding and trauma leads to an unstable and tenuous physiologic state, conventional coagulation tests (CCTs) are too slow to diagnose, manage, and also course correct any hemostatic abnormalities that accompany an acute critical illness. Viscoelastic point-of-care tests strongly correlate with results from standard laboratory tests but are designed to enable clinicians to make timely, informed bleeding management decisions when time to intervene is critical. These assays provide an individualized and goal-oriented approach to patient blood management and are increasingly becoming involved in transfusion algorithms. The scope of this review aims to evaluate the current literature on VETs and their impact on actionable outputs in clinical decision making and their relationship to CCT.

The Choice between Plasma-Based Common Coagulation Tests and Cell-Based Viscoelastic Tests in Monitoring Hemostatic Competence: Not an either-or Proposition

There has been a significant interest in the last decade in the use of viscoelastic tests (VETs) to determine the hemostatic competence of bleeding patients. Previously, common coagulation tests (CCTs) such as the prothrombin time (PT) and partial thromboplastin time (PTT) were used to assist in the guidance of blood component and hemostatic adjunctive therapy for these patients. However, the experience of decades of VET use in liver failure with transplantation, cardiac surgery, and trauma has now spread to obstetrical hemorrhage and congenital and acquired coagulopathies. Since CCTs measure only 5 to 10% of the lifespan of a clot, these assays have been found to be of limited use for acute surgical and medical conditions, whereby rapid results are required. However, there are medical indications for the PT/PTT that cannot be supplanted by VETs. Therefore, the choice of whether to use a CCT or a VET to guide blood component therapy or hemostatic adjunctive therapy may often require consideration of both methodologies. In this review, we provide examples of the relative indications for CCTs and VETs in monitoring hemostatic competence of bleeding patients.

Utility of viscoelastic hemostatic assay to guide hemostatic resuscitation in trauma patients: a systematic review

Objective

Viscoelastic hemostatic assay (VHA) provides a graphical representation of a clot’s lifespan and reflects the real time of coagulation. It has been used to guide trauma resuscitation; however, evidence of the effectiveness of VHAs is still limited. This systematic review aims to summarize the published evidence to evaluate the VHA-guided strategy in resuscitating trauma patients.

Methods

The PubMed, Embase, and Web of Science databases were searched from their inception to December 13, 2021. Randomized controlled trials (RCTs) or observational studies comparing VHA-guided transfusion to controls in resuscitating trauma patients were included in this systematic review.

Results

Of the 7743 records screened, ten studies, including two RCTs and eight observational studies, met the inclusion criteria. There was great heterogeneity concerning study design, enrollment criterion, VHA device, VHA-guided strategy, and control strategy. Thrombelastography (TEG) was used as a guiding tool for transfusion in eight studies, and rotational thromboelastometry (ROTEM), and TEG or ROTEM were used in the other two studies. The overall risk of bias assessment was severe or mild in RCTs and was severe or moderate in observational studies. The main outcomes reported from the included studies were blood transfusion (n = 10), mortality (n = 10), hospital length of stay (LOS) (n = 7), intensive care unit LOS (n = 7), and cost (n = 4). The effect of the VHA-guided strategy was not always superior to the control. Most of the studies did not find significant differences in the transfusion amount of red blood cells (n = 7), plasma (n = 5), platelet (n = 7), cryoprecipitate/fibrinogen (n = 7), and mortality (n = 8) between the VHA-guided group and control group. Notable, two RCTs showed that the VHA-guided strategy was superior or equal to the conventional coagulation test-guided strategy in reducing mortality, respectively.

Conclusion

Although some studies demonstrated VHA-guided strategy probable benefit in reducing the need for blood transfusion and mortality when resuscitating trauma patients, the evidence is still not robust. The quality of evidence was primarily downgraded by the limited number of included studies and great heterogeneity and severe risk of bias in these. Further studies are strongly recommended.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13017-022-00454-8.

Thromboelastography-Guided Therapy Enhances Patient Blood Management in Cirrhotic Patients: A Meta-analysis Based on Randomized Controlled Trials

Patients with cirrhosis often have abnormal hemostasis, with increased risk of hemorrhage and thrombosis. Thromboelastography provides a rapid assessment of the coagulation status and can guide product transfusions in adult patients with cirrhosis. This study aimed to determine whether the use of thromboelastography in adult patients with cirrhosis decreases blood product use and impacts adverse events or mortality compared with standard practice. A registered (PROSPERO CRD42020192458) systematic review and meta-analysis was conducted for randomized controlled trials (RCTs) comparing thromboelastography-guided hemostatic management versus standard practice (control). Co-primary outcomes were the number of transfused platelet units and fresh frozen plasma (FFP) units. Secondary outcomes were mortality, adverse events, utilization of individual blood products, blood loss or excessive bleeding events, hospital/intensive care unit stay, and liver transplant/intervention outcomes. The search identified 260 articles, with five RCTs included in the meta-analysis. Platelet use was five times lower with thromboelastography versus the control, with a relative risk of 0.17 (95% confidence interval [CI]: [0.03-0.90]; p = 0.04), but FFP use did not differ significantly. Thromboelastography was associated with less blood product (p < 0.001), FFP + platelets (p < 0.001), and cryoprecipitate (p < 0.001) use. No differences were reported in bleeding rates or longer term mortality between groups, with the thromboelastography group having lower mortality at 7 days versus the control (relative risk [95% CI] = 0.52 [0.30-0.91]; p = 0.02). Thromboelastography-guided therapy in patients with cirrhosis enhances patient blood management by reducing use of blood products without increasing complications.

Thromboelastography-Guided Therapy Enhances Patient Blood Management in Cirrhotic Patients: A Meta-analysis Based on Randomized Controlled Trials

Patients with cirrhosis often have abnormal hemostasis, with increased risk of hemorrhage and thrombosis. Thromboelastography provides a rapid assessment of the coagulation status and can guide product transfusions in adult patients with cirrhosis. This study aimed to determine whether the use of thromboelastography in adult patients with cirrhosis decreases blood product use and impacts adverse events or mortality compared with standard practice. A registered (PROSPERO CRD42020192458) systematic review and meta-analysis was conducted for randomized controlled trials (RCTs) comparing thromboelastography-guided hemostatic management versus standard practice (control). Co-primary outcomes were the number of transfused platelet units and fresh frozen plasma (FFP) units. Secondary outcomes were mortality, adverse events, utilization of individual blood products, blood loss or excessive bleeding events, hospital/intensive care unit stay, and liver transplant/intervention outcomes. The search identified 260 articles, with five RCTs included in the meta-analysis. Platelet use was five times lower with thromboelastography versus the control, with a relative risk of 0.17 (95% confidence interval [CI]: [0.03-0.90]; p = 0.04), but FFP use did not differ significantly. Thromboelastography was associated with less blood product (p < 0.001), FFP + platelets (p < 0.001), and cryoprecipitate (p < 0.001) use. No differences were reported in bleeding rates or longer term mortality between groups, with the thromboelastography group having lower mortality at 7 days versus the control (relative risk [95% CI] = 0.52 [0.30-0.91]; p = 0.02). Thromboelastography-guided therapy in patients with cirrhosis enhances patient blood management by reducing use of blood products without increasing complications.

Risk stratification for pregnancy-associated venous thromboembolism: Potential role for global coagulation assays

Risk assessment for venous thromboembolism in pregnancy and the puerperium is currently limited to stratifying clinical surrogate risk factors without high-quality evidence. While the absolute risk of pregnancy-associated venous thromboembolism is low for the vast majority of women, associated morbidity and mortality remains significant. As guidelines for thromboprophylaxis vary widely, some women may be under- or over-anticoagulated, contributing to poor outcomes. New global coagulation assays provide a holistic view of coagulation and may have the potential to detect hypercoagulability in pregnancy, unlike clinically available coagulation assays. However, there are major technical challenges to overcome before global coagulation assays can be realistically proposed as an adjunct to risk assessment for pregnancy-associated venous thromboembolism. This review summarises the literature and controversies in the prediction and prevention of pregnancy-associated venous thromboembolism and outlines the new tools in haematology that may assist in our future understanding of hypercoagulability in pregnancy.

Case Report: Thromboelastography for uremic thrombocytopathy in a patient with COVID-19

Uremia causes several biochemical and physiological impairments that result in the accumulation of toxins with multiple clinical effects. Bleeding is one of the most common complications of acute and chronic renal failure. The pathogenesis of uremic bleeding is multifactorial, of which uremic thrombocytopathy is the most described clinically. Various tests have been used to evaluate bleeding diathesis in these patients including bleeding time, prothrombin time, activated partial thromboplastin time, and international normalized ratio, but there are only a few studies that use thromboelastography as a point-of-care test to identify platelet dysfunction. In addition, COVID-19 increases hemorrhagic complications due to platelet dysfunction or hemostasis exhaustion. COVID-19 could also potentially cause platelet dysfunction as a secondary consequence of acute kidney injury. There are only a few studies reporting the use of thromboelastography in COVID-19-induced hypercoagulability, but not in diagnosing or managing platelet-related abnormalities. We present a patient with COVID-19 who developed acute kidney injury in the hospital and retroperitoneal hemorrhage from uremic platelet dysfunction. We used point-of-care thromboelastography with platelet mapping to determine uremic platelet dysfunction.

Prevention of Deep Vein Thrombosis by Panax Notoginseng Saponins Combined with Low-Molecular-Weight Heparin in Surgical Patients

OBJECTIVE

To evaluate the efficacy of deep vein thrombosis (DVT) prevention among real-world surgical inpatients who received panax notoginseng saponins (PNS) combined with low-molecular-weight heparin (LMWH).

METHODS

A prospective cohort study was conducted among surgical patients between January 2016 and November 2018 in Xuanwu Hospital, Capital Medical University, Beijing, China. Participants received LMWH alone or PNS combined with LMWH for preventing DVT. The primary outcome was incidence of lower extremity DVT, which was screened once a week. Participants in the LMWH group were given LMWH (enoxaparin) via hypodermic injection, 4000-8000 AxalU once daily. Participants in the exposure group received PNS (Xuesaitong oral tablets, 100 mg, 3 times daily) combined with LMWH given the same as LMWH group.

RESULTS

Of the 325 patients screened for the study, 281 participants were included in the final analysis. The cohort was divided into PNS + LMWH group and LMWH group with 134 and 147 participants, respectively. There was a significant difference of DVT incidence between two groups (P=0.01), with 21 (15.7%) incident DVT in the PNS + LMWH group, and 41 (27.9%) incident DVT in the LMWH group. Compared with participants without DVT, the participants diagnosed with DVT were older and had higher D-dimer level. The multivariate logistic regression model showed a significant lower risk of incident DVT among participants in the PNS + LMWH group compared with the LMWH group (odds ratio 0.46, 95% confidence interval, 0.25-0.86). There were no significant differences in thromboelaslography values (including R, K, Angle, and MA) and differences in severe bleeding between two groups. No symptomatic pulmonary embolism occurred during the study.

CONCLUSION

Combined application of PNS and LMWH can effectively reduce the incidence of DVT among surgical inpatients compared with LMWH monotherapy, without increased risk of bleeding.

Association Between Thromboelastography and Coronary Heart Disease

BACKGROUND Thromboelastography (TEG) is a novel blood viscoelasticity detection method revealing blood coagulation status and has been reported to be helpful in predicting clinical outcomes in patients with cardiovascular diseases (CVD). In this study, we aimed to investigate the association between TEG and CVD. MATERIAL AND METHODS A single-center case-control study was performed. Individuals who took TEG tests at Tongji Hospital in Wuhan, China from 2015 to 2019 were included. The nearest-neighbor Mahalanobis matching with replacement, within propensity score calipers of 0.25 was used to control the covariate imbalance between CVD patients and controls. Logistic regression analyses were conducted to assess the relationship between TEG and CVD. Subgroup and sensitivity analyses were performed to evaluate the robustness of the association between TEG and CVD. RESULTS After matching, a total of 151 participants were included in this study, with 83 patients having CVD (49 patients having coronary heart disease [CHD] and 34 patients having an ischemic stroke). By comparison, CHD patients had a significantly higher maximum amplitude (MA) (P=0.02) than controls. After multivariable adjustment, MA (OR 1.11, 95% CI 1.01-1.24, P=0.04) was independently associated with CHD. The association between MA and CHD remained robust across subgroups and in sensitivity analyses. CONCLUSIONS The current study suggests that MA is significantly associated with CHD. Enhanced platelet reactivity as described by high MA might be associated with risk of CHD. The exact role of MA in the measurement of CHD risk needs to be further examined in large-scale prospective cohort studies.

The clinical effect and safety of new preoperative fasting time guidelines for elective surgery: a systematic review and meta-analysis

BACKGROUND

Traditional fasting and no drinking schemes (fasting for 8-12 hours and no drinking for 4-6 hours) affect the metabolism of the body. The new guidelines put forward by the American Association of Anesthesiologists (fasting for 6 hours, no drinking for 2 hours) obviously reduce the time of fasting and no drinking, but the clinical efficacy and safety need to be further confirmed. In this study, a meta-analysis of randomized controlled trials (RCTs) using the new guidelines and traditional protocols was conducted to provide an evidence-based foundation for elective surgery.

METHODS

The articles were searched in PubMed, EBSCO, MEDLINE, Science Direct, Cochrane Library, CNKI, China Biomedical Resources Database, Wanfang Database, Weipu, and Western Biomedical Journal Literature Database. RCTs related to fasting before surgery during the screening period were selected. Chinese and English search keywords included elective surgery, preoperative, fasting and no drinking, patient comfort, thirst, hunger, collapse, hypoglycemia, preoperative gastric volume, preoperative gastric juice pH, and intraoperative gastric volume. The RevMan 5.3 software provided by Cochrane collaboration network was used to evaluate the quality of included documents. Two professionals independently screened the literature, extracted data, and assessed the risk of bias.

RESULTS

A total of 6 studies were included. The incidence of hunger in patients undergoing elective surgery in the experimental group and control group was significantly different [Z=3.90; relative risk (RR) =0.58; 95% confidence interval (CI): 0.44, 0.76; P<0.0001]. The incidence of thirst was significantly different between the experimental group and control group (Z=7.22; RR =0.21; 95% CI: 0.13, 0.32; P<0.00001).

DISCUSSION

Meta-analysis results confirmed that the new guidelines can significantly reduce the hunger and thirst of patients, improve their satisfaction after surgery, and can be applied clinically.

Viscoelastic haemostatic point-of-care assays in the management of postpartum haemorrhage: a narrative review

Viscoelastic haemostatic assays provide rapid testing at the bed-side that identify all phases of haemostasis, from initial fibrin formation to clot lysis. In obstetric patients, altered haemostasis is common as pregnancy is associated with coagulation changes that may contribute to bleeding events such as postpartum haemorrhage, as well as thrombosis events. In this narrative review, we examine the potential clinical utility of viscoelastic haemostatic assays in postpartum haemorrhage and consider the current recommendations for their use in obstetric patients. We discuss the clinical benefits associated with the use of viscoelastic haemostatic assays due to the provision of (near) real-time readouts with a short turnaround, coupled with the identification of coagulation defects such as hypofibrinogenaemia. The use of viscoelastic haemostatic assay-guided algorithms may be beneficial to diagnose coagulopathy, predict postpartum haemorrhage, reduce transfusion requirements and monitor fibrinolysis in women with obstetric haemorrhage. Further studies are required to assess whether viscoelastic haemostatic assay-guided treatment improves clinical outcomes, and to confirm the utility of prepartum viscoelastic haemostatic assay measurements for identifying patients at risk of postpartum haemorrhage.

Role of Value-Added Care by Cardiothoracic Anesthesiology and Impact on Outcomes After Cardiac Surgery

The medical community is increasingly aware of the need for high-quality and high-value patient care. Anesthesiologists in particular have long demonstrated leadership in the field of quality and safety. Cardiothoracic anesthesiologists can improve the quality of care delivered to cardiac patients both with anesthesia-specific practices and in a team-based approach with other perioperative care providers. Collecting large volumes of multicentered data to study, measure, and improve anesthesia care is one of the many commitments of cardiothoracic anesthesiologists to this cause. This article reviews this and other aspects of the work of cardiothoracic anesthesiologists to improve value-added care to cardiac patients.

Optimizing fresh-frozen plasma transfusion in surgical neonates through thromboelastography: a quality improvement study

Fresh frozen plasma (FFP) is largely misused in the neonatal setting. The aim of the study is to evaluate the impact of a Thromboelastography (TEG)-based Quality Improvement (QI) project on perioperative FFP use and neonatal outcomes. Retrospective pre-post implementation study in a level-III NICU including all neonates undergoing major non-cardiac surgery before (01-12/2017) and after (01-12/2019) the intervention. In 2018, the intervention included the following: (1) Training on TEG, (2) Implementation of TEG, and (3) Algorithm for TEG-directed FFP administration in surgical neonates. We compared pre- vs post-intervention patient characteristics, hemostasis, and clinical management. Linear and logistic regression models were used to evaluate the impact of the project on main outcomes. We analyzed 139 neonates (pre-intervention: 72/post-intervention: 67) with a mean (± SD) gestational age (GA) 34.9 (± 5) weeks and birthweight 2265 (± 980) grams which were exposed to 184 surgical procedures (pre-intervention: 91/post-intervention: 93). Baseline characteristics were similar between periods. In 2019, prothrombin time (PT) was longer (14.3 vs 13.2 s; p < 0.05) and fibrinogen was lower (229 vs 265 mg/dl; p < 0.05), if compared to 2017. In 2019, the intraoperative exposure to FFP decreased (31% vs 60%, p < 0.001), while the pre-operative FFP use did not change. The reduction of intraoperative FFP did not impact on mortality and morbidity. Intraoperative FFP use was lower in the post-intervention even after controlling for GA, American Society of Anesthesiologists score, PT, and fibrinogen (Odds ratio: 0.167; 95% CI: 0.070, 0.371).   Conclusion: The TEG-based QI project for the management of FFP during neonatal surgery reduced intraoperative FFP exposure. What is Known: • PT and aPTT are poor predictors of bleeding risk in acquired neonatal coagulopathy, leading to likely unnecessary fresh frozen plasma (FFP) transfusion in the Neonatal Intensive Care Setting.  • As neonatal hemostasis is a delicate balance between the concomitant reduction of pro- and anti-coagulants drivers, thromboelastography (TEG) is a promising alternative for coagulation monitoring. What is New: • The implementation of TEG, training, and shared protocols contributed to reduced intraoperative FFP use, which was not associated with increased mortality or bleeding events. • These findings inform future research showing that there is clinical equipoise to allow for larger studies to confirm the use of TEG in NICUs and to identify TEG cut-offs for transfusion practice.

The Role of TEG and ROTEM in Damage Control Resuscitation

ABSTRACT

Trauma-induced coagulopathy is associated with very high mortality, and hemorrhage remains the leading preventable cause of death after injury. Directed methods to combat coagulopathy and attain hemostasis are needed. The available literature regarding viscoelastic testing, including thrombelastography (TEG) and rotational thromboelastometry (ROTEM), was reviewed to provide clinically relevant guidance for emergency resuscitation. These tests predict massive transfusion and developing coagulopathy earlier than conventional coagulation testing, within 15 min using rapid testing. They can guide resuscitation after trauma, as well. TEG and ROTEM direct early transfusion of fresh frozen plasma when clinical gestalt has not activated a massive transfusion protocol. Reaction time and clotting time via these tests can also detect clinically significant levels of direct oral anticoagulants. Slowed clot kinetics suggest the need for transfusion of fibrinogen via concentrates or cryoprecipitate. Lowered clot strength can be corrected with platelets and fibrinogen. Finally, viscoelastic tests identify fibrinolysis, a finding associated with significantly increased mortality yet one that no conventional coagulation test can reliably detect. Using these parameters, guided resuscitation begins within minutes of a patient's arrival. A growing body of evidence suggests this approach may improve survival while reducing volumes of blood products transfused.

Obstetrical Hemorrhage

Obstetric hemorrhage is a leading cause of morbidity and mortality. Prevention includes identifying patients with risk factors and actively managing the third stage of labor. The anesthesiologist should be ready to manage hemorrhage with general strategies as well as strategies tailored to the specific cause of hemorrhage. Both neuraxial anesthesia and general anesthesia are appropriate in different situations. Treatments proven to be effective include increasing the oxytocin infusion, administering tranexamic acid early, guiding transfusion with point-of-care tests, and using cell salvage. Utilization of protocols and checklists within systems that encourage effective communication between teams should be implemented.

Adult liver transplant anesthesiology practice patterns and resource utilization in the United States: Survey results from the society for the advancement of transplant anesthesia

INTRODUCTION

Liver transplant anesthesiology is an evolving and expanding subspecialty, and programs have, in the past, exhibited significant variations of practice at transplant centers across the United States. In order to explore current practice patterns, the Quality & Standards Committee from the Society for the Advancement of Transplant Anesthesia (SATA) undertook a survey of liver transplant anesthesiology program directors.

METHODS

Program directors were invited to participate in an online questionnaire. A total of 110 program directors were identified from the 2018 Scientific Registry of Transplant Recipients (SRTR) database. Replies were received from 65 programs (response rate of 59%).

RESULTS

Our results indicate an increase in transplant anesthesia fellowship training and advanced training in transesophageal echocardiography (TEE). We also find that the use of intraoperative TEE and viscoelastic testing is more common. However, there has been a reduction in the use of veno-venous bypass, routine placement of pulmonary artery catheters and the intraoperative use of anti-fibrinolytics when compared to prior surveys.

CONCLUSION

The results show considerable heterogeneity in practice patterns across the country that continues to evolve. However, there appears to be a movement towards the adoption of specific structural and clinical practices.

The role of viscoelastic testing in assessing peri-interventional platelet function and coagulation

We carried out a literature search in MEDLINE (PubMed) and EMBASE literature databases to provide a concise review of the role of viscoelastic testing in assessing peri-interventional platelet function and coagulation. The search identified 130 articles that were relevant for the review, covering the basic science of VHA and VHA in clinical settings including cardiac surgery, cardiology, neurology, trauma, non-cardiac surgery, obstetrics, liver disease, and COVID-19. Evidence from these articles is used to describe the important role of VHAs and platelet function testing in various peri-interventional setups. VHAs can help us to comprehensively assess the contribution of platelets and coagulation dynamics to clotting at the site-of-care much faster than standard laboratory measures. In addition to standard coagulation tests, VHAs are beneficial in reducing allogeneic transfusion requirements and bleeding, in predicting ischemic events, and improving outcomes in several peri-interventional care settings. Further focused studies are needed to confirm their utility in the peri-interventional case.

Trauma-induced coagulopathy

Uncontrolled haemorrhage is a major preventable cause of death in patients with traumatic injury. Trauma-induced coagulopathy (TIC) describes abnormal coagulation processes that are attributable to trauma. In the early hours of TIC development, hypocoagulability is typically present, resulting in bleeding, whereas later TIC is characterized by a hypercoagulable state associated with venous thromboembolism and multiple organ failure. Several pathophysiological mechanisms underlie TIC; tissue injury and shock synergistically provoke endothelial, immune system, platelet and clotting activation, which are accentuated by the 'lethal triad' (coagulopathy, hypothermia and acidosis). Traumatic brain injury also has a distinct role in TIC. Haemostatic abnormalities include fibrinogen depletion, inadequate thrombin generation, impaired platelet function and dysregulated fibrinolysis. Laboratory diagnosis is based on coagulation abnormalities detected by conventional or viscoelastic haemostatic assays; however, it does not always match the clinical condition. Management priorities are stopping blood loss and reversing shock by restoring circulating blood volume, to prevent or reduce the risk of worsening TIC. Various blood products can be used in resuscitation; however, there is no international agreement on the optimal composition of transfusion components. Tranexamic acid is used in pre-hospital settings selectively in the USA and more widely in Europe and other locations. Survivors of TIC experience high rates of morbidity, which affects short-term and long-term quality of life and functional outcome.

Assessing in-hospital cardiovascular, thrombotic and bleeding outcomes in patients with chronic liver disease undergoing left ventricular assist device implantation

INTRODUCTION

Chronic liver disease (CLD) and advanced heart failure (HF) often co-exist with coagulopathy and hematologic abnormalities being major concerns in this cohort. Perioperative outcomes of patients undergoing LVAD implantation can be affected by coagulopathy, associated with a higher International Normalized Ratio (INR) and cytopenias, as well as pre-operative use of antiplatelet therapy and systemic anticoagulation. Our study is aimed at evaluating the in-hospital mortality and clinical outcomes of patients with CLD who underwent LVAD implantation compared to patients who underwent LVAD implantation without CLD.

METHODS

The National Inpatient Sample Database was queried from 2012 to 2017 for relevant International Classification of Diseases (ICD)-9 and ICD-10 procedural and diagnostic codes. Baseline characteristics and in-hospital outcomes were compared in patients with chronic liver disease and those without, who underwent LVAD implantation.

RESULTS

A total of 22,955 patients underwent LVAD implantation, 2200 of which had CLD. There was no difference in mean age between those with and without CLD (52.8 ± 14.2 vs. 55.7 ± 15.4 years old, p < 0.001), and 23.7% of patients were female. The proportion of patients with CLD undergoing LVAD implantation trended downward between 2012 and 2017 (average annual growth rate: "-14.8%"). In-hospital post-LVAD outcomes revealed: all-cause inpatient mortality (14.8% vs. 11.1%), major bleeding (34.3% vs. 30.2%), transfusion of platelets (18.0% vs. 14.0%), subarachnoid hemorrhage (1.6% vs. 0.7%) and hospital length of stay were greater in patients with CLD (p < 0.001 for all values). LVAD thrombosis (6.6% vs. 9.4%) and postoperative ischemic stroke (3.4% vs. 6.1%) occurred less in patients with CLD (p < 0.001 for both). There were no statistically significant differences in occurrence of post-LVAD gastrointestinal bleeding and transfusion of fresh frozen plasma or packed red blood cells (p > 0.05 for all). Using a multivariate logistic regression model to adjust for confounding factors, CLD was predictive of increased in-hospital all-cause mortality in patients undergoing LVAD implantation (adjusted odds ratio: 1.29, 95% confidence interval [CI]; 1.06 to 1.56, p = 0.010).

CONCLUSION

LVAD implantation in patients with chronic liver disease was associated with increased mortality and post-LVAD major bleeding with increased utilization of platelet products yet comparable thrombotic complications. Further studies are needed to evaluate the balance and pathophysiology of bleeding risks when compared to thrombosis, as well as predictors in patients with chronic liver disease.

Comparison of three common whole blood platelet function tests for in vitro P2Y12 induced platelet inhibition

In the context of interventional cardiology, platelet function testing may identify patients treated with P2Y12-inhibitors at an increased risk of mortality, thrombosis and bleeding. Several whole blood point-of-care platelet function analyzers are available; however, inter-device differences have not been examined systematically. To compare three platelet function tests under standardized in vitro conditions. Healthy volunteer (n = 10) blood samples were spiked with increasing concentrations of ticagrelor (0–7500 ng/mL) and/or ASA (0–3280 ng/mL), measured on three platelet function analyzers (TEG^®6s, Multiplate^®, and VerifyNow^®) and respective Effective Concentration (EC) levels EC10, EC50 and EC90 were calculated. Repeatability was assessed in a separate group of pooled blood samples (n = 10) spiked with ticagrelor at EC10, EC50 and EC90. ASA had no impact on ADP-activated channels for all three devices. TEG^®6s was able to distinguish (p ≤ 0.05) between all ticagrelor EC zones; VerifyNow^® and Multiplate^® were able to distinguish between three and two zones, respectively. Multiplate^® showed the largest window between EC10 and EC90 (19–9153 ng/mL), followed by TEG^®6s (144–2589 ng/mL), and VerifyNow^® (191–1100 ng/mL). Drug effect models distribution of disagreements were identified for TEG^®6s (5.0%), VerifyNow^® (8.3%), and Multiplate^® (13.3%). TEG^®6s showed the smallest average coefficient of variation between EC conditions (5.1%), followed by Multiplate^® (14.1%), and VerifyNow^® (17.7%). Linear models could be generated between TEG^®6s and Multiplate^®, but not VerifyNow^®. Significant differences were found between whole blood point-of-care platelet function analyzers and the clinical impact of these differences needs to be further investigated.

When and how should I transfuse during obstetric hemorrhage?

The incidence of maternal hemorrhage and blood transfusion has increased over time. Causes of massive hemorrhage, defined as a transfusion > 10 units of erythrocytes, include abnormal placental insertion, preeclampsia, and placental abruption. Although ratio-based transfusion has been described for managing massive hemorrhage, a goal-directed approach using laboratory or point-of-care data may lead to better outcomes. Autotransfusion, which involves the collection, washing, and filtration of maternal shed blood, avoids many of the complications associated with allogeneic blood transfusion. In this review, we provide an overview of transfusion practices related to the management of obstetric hemorrhage.

Viscoelastic Haemostatic Assays in Cardiovascular Critical Care

The initiation and management of anticoagulation is a fundamental practice for a wide variety of indications in cardiovascular critical care, including the management of patients with acute MI, stroke prevention in patients with AF or mechanical valves, as well as the prevention of device thrombosis and thromboembolic events with the use of mechanical circulatory support and ventricular assist devices. The frequent use of antiplatelet and anticoagulation therapy, in addition to the presence of concomitant conditions that may lead to a propensity to bleed, such as renal and liver dysfunction, present unique challenges. The use of viscoelastic haemostatic assays provides an additional tool allowing clinicians to strike a delicate balance of attaining adequate anticoagulation while minimising the risk of bleeding complications. In this review, the authors discuss the role that viscoelastic haemostatic assay plays in cardiac populations (including cardiac surgery, heart transplantation, extracorporeal membrane oxygenation, acute coronary syndrome and left ventricular assist devices), and identify areas in need of further study.

Massive Transfusion in Pediatric Patients

Massive transfusion in pediatric patients is infrequent but associated with much higher mortality than in adults. Blood transfusion and hematology has conceptualized ideas such as blood failure and the interplay of the blood-endothelium interface to understand coagulopathy in the context of hemorrhagic shock. Researchers are still searching for an appropriate definition of what constitutes a pediatric massive transfusion. There is no universally accepted protocol for massive transfusion and how to address the many complications that can arise. Pharmacologic adjuncts to resuscitation may prove beneficial in reducing coagulopathy during pediatric massive transfusion, but high-quality evidence has not yet emerged.

Detection of hypofibrinogenemia during cardiac surgery: a comparison of resonance-based thrombelastography with the traditional Clauss method

: Bleeding after cardiac surgery is associated with significant morbidity and mortality. Hypofibrinogenemia is a crucial factor for bleeding in this setting and may be rapidly detected using point-of-care viscoelastic tests (POC-VET). However, the correlation of POC-VET with conventional coagulation assays is still unclear. The current study aimed to correlate resonance-based POC-VET assays (Haemonetics TEG 6s) with the traditional nonrapid Clauss method. Another aim was to identify a cut-off value for the detection of hypofibrinogenemia (fibrinogen plasma level below 150 mg/dl) focusing on the maximum amplitude of the TEG 6s citrated functional fibrinogen (CFF) assay. Adult patients undergoing cardiac surgery were screened for inclusion in this single-centre retrospective cohort study. Inclusion criteria were the availability of a TEG assay and timely corresponding laboratory results. Calculation of a CFF-maximum amplitude (CFF-MA) cut-off value was performed using receiver operating curve analysis in the baseline cohort and validated in the control cohort. The best correlation with the Clauss method was observed for the CFF-MA (r = 0.77; P < 0.0001) compared with the citrate kaolin maximum amplitude assay (r = 0.57; P < 0.0001) and the citrate kaolin heparinase maximum amplitude assay (r = 0.67; P < 0.0001). A cut-off value of 19.9 mm for the CFF-MA was calculated [area under the curve 0.87 (95% confidence interval: 0.82-0.92; P < 0.0001)]. This cut-off value had a sensitivity of 81.8% and a specificity of 71.1% for identification of hypofibrinogenemia in the control cohort. The resonance-based thrombelastography analyser can identify hypofibrinogenemia. Future clinical studies should investigate whether cut-off value guided coagulation therapy with POC-VET may improve patient outcomes in patients who suffer from bleeding complications.