ROTEM diagnostic capacity for measuring fibrinolysis in neonatal sepsis

Neonatal hemostasis and the use of thromboelastography/rotational thromboelastometry in the neonatal period

Developmental hemostasis refers to age-related alterations related to the progressive maturation of the hemostatic system. Although the conventional coagulation tests, such as prothrombin time (PT) and activated partial thromboplastin time (aPTT), are indeed helpful in coagulation workup, they do not accurately delineate the hemostasis in vivo. The viscoelastic tests, namely thromboelastography (TEG) and rotational thromboelastometry (ROTEM), seem to reflect hemostasis more accurately since they measure various clot parameters without excluding the cellular coagulation components. TEG and ROTEM have shown redaction in blood product administration when used in therapeutic algorithms in older children and adults, but their use in neonates is limited. This review summarizes the current literature regarding using these tests in the neonatal population. Several studies tried to resolve the lack of neonatal reference values of the TEG/ROTEM parameters by publishing neonatal reference ranges for various gestational age groups. Moreover, few studies concerning therapeutic hypothermia, neonates undergoing surgery, and critically ill neonates have shown some predictive value of these tests regarding bleeding events. Even though their results seem promising, larger studies of higher quality are needed to clarify any discrepancies and point out whether these tests have significant predictive value. In conclusion, viscoelastic tests need to be increasingly part of the NICUs' clinical routine and should be used along with conventional coagulation tests in transfusion therapy.

Assessment of hemostatic profile in neonates with necrotizing enterocolitis using Rotational Thromboelastometry (ROTEM)

BACKGROUND

This study aimed to explore the hemostatic profile of neonates with necrotizing enterocolitis (NEC) using Rotational Thromboelastometry (ROTEM) and to investigate if ROTEM parameters have the capacity to play a role in the differentiation of NEC from sepsis at the disease onset.

METHODS

This observational study included 62 neonates (mean gestational age 31.6 weeks and mean birth weight 1620g) hospitalized in a neonatal intensive care unit. The neonates were categorized in three groups: neonates with NEC (Bell stage II and above), neonates with sepsis and healthy neonates and they were matched 1:1:1 with regards to gestational age, delivery mode, and sex. Clinical, laboratory data as well as measurements of ROTEM parameters at disease onset were recorded.

RESULTS

ROTEM parameters differed between neonates with NEC and neonates with sepsis, indicating that NEC results in accelerated clot formation and higher clot strength compared to sepsis. The EXTEM CFT and A10 parameters demonstrated the highest diagnostic performance for NEC in terms of discrimination between NEC and sepsis (AUC, 0.997; 95% CI: 0.991-1.000 and 0.973; 95% CI: 0.932-1.000, respectively).

CONCLUSIONS

Neonates with NEC manifested accelerated clot formation and higher clot strength compared to septic and healthy neonates, as these were expressed by ROTEM parameters.

IMPACT

This work reports data on the hemostatic profile of neonates with necrotizing enterocolitis (NEC) using Rotational Thromboelastometry (ROTEM) and the capacity of ROTEM parameters in differentiating of NEC from sepsis at the disease onset. Neonates with NEC present acceleration of coagulation and exhibit a hypercoagulable profile, as this is expressed by ROTEM parameters, in comparison to septic and healthy neonates. ROTEM parameters demonstrated a good diagnostic capacity in differentiating NEC from sepsis at the disease onset.

Contemporary tools for evaluation of hemostasis in neonates. Where are we and where are we headed?

The assessment of hemostatic disorders in neonates is crucial, but remains challenging for clinicians. Although the concept of developmental hemostasis is widely accepted among hemostasis specialists globally, it is probably under-recognized by clinicians and laboratory practitioners. In parallel with age-dependent hemostatic status maturation, comprehension of the differences between normal values is crucial for the accurate diagnosis of potential hemorrhagic and thrombotic disorders of the vulnerable neonatal population. This review outlines the basics of developmental hemostasis and the features of the available coagulation testing methods, with a focus on novel tools for evaluating the neonatal hemostatic profile. Common errors, issues, and pitfalls during the assessment of neonatal hemostasis are discussed, along with their impact on patient management. Current knowledge gaps and research areas are addressed. Further studying to improve our understanding of developmental hemostasis and its reflection on everyday clinical practice is warranted.

Assessment of Hemostatic Profile in Neonates with Intrauterine Growth Restriction: A Systematic Review of Literature

Intrauterine growth restriction (IUGR) affects nearly 10 to 15% of pregnancies and is responsible for many short- and long-term adverse consequences, including hemostatic derangement. Both thrombotic and hemorrhagic events are described in the perinatal period in these neonates. The aim of this study was to systematically review the literature on the laboratory studies used to evaluate the hemostatic system of the IUGR small for gestational age neonate. We reviewed the current literature via PubMed and Scopus until September 2022. Following our inclusion/exclusion criteria, we finally included 60 studies in our review. Thrombocytopenia, characterized as hyporegenerative and a kinetic upshot of reduced platelet production due to in utero chronic hypoxia, was the main finding of most studies focusing on growth-restricted neonates, in most cases is mild and usually resolves spontaneously with the first 2 weeks of life. In regard to coagulation, growth-restricted newborns present with prolonged standard coagulation tests. Data regarding coagulation factors, fibrinolytic system, and anticoagulant proteins are scarce and conflicting, mainly due to confounding factors. As thromboelastography/rotational thromboelastometry (TEG/ROTEM) provides a more precise evaluation of the in vivo coagulation process compared with standard coagulation tests, its use in transfusion guidance is fundamental. Only one study regarding TEG/ROTEM was retrieved from this population, where no difference in ROTEM parameters compared with appropriate for gestational age neonates was found. Despite the laboratory aberrations, no correlation could be achieved with clinical manifestations of bleeding or thrombosis in the studies included. More studies are needed to assess hemostasis in IUGR neonates and guide targeted therapeutic interventions.

Thromboelastometry and prediction of in-hospital mortality in neonates with sepsis

INTRODUCTION

This study aimed at evaluating the role of rotational thromboelastometry (ROTEM) assays in the prediction of in-hospital mortality of neonates with sepsis.

METHODS

Over a 6-year period, 129 neonates with confirmed sepsis, hospitalized in our neonatal intensive care unit (NICU) were included in the study. Demographics, clinical, and laboratory data were recorded at the sepsis onset and ROTEM assays were performed. Modified neonatal multiple organ dysfunction (NEOMOD) and neonatal sequential organ failure assessment (nSOFA) were calculated simultaneously. Mortality during in-hospital stay was the main outcome measure.

RESULTS

In-hospital mortality was associated with patient intense hypocoagulability expressed by lower ROTEM MCF in the INTEM assay. The INTEM MCF demonstrated the best prognostic performance for NICU mortality in septic neonates among the other ROTEM parameters but without statistical significance (area under the curve [AUC] = 0.731; 95% confidence interval [CI]: 0.593-0.869).

CONCLUSION

Our results indicate that ROTEM INTEM MCF parameter has good predictive capacity for in-hospital mortality of septic neonates, similar to that of modified NEOMOD score, nSOFA score, and platelet count, highlighting the integral role of coagulation in sepsis pathophysiology. Hence, ROTEM could serve as a valuable monitoring tool to identify neonates at risk.

Coagulation profiles in patients with sepsis/septic shock identify mixed hypo-hypercoagulation patterns based on rotational thromboelastometry: A prospective observational study

INTRODUCTION

Sepsis-induced hemostatic disturbances are common and are associated with poor outcomes. Additionally, conventional coagulation tests (CCTs) overdiagnose hypocoagulation and cannot detect hypercoagulation and hyperfibrinolysis. The aim of this study was to describe the coagulation profiles of patients with sepsis/septic shock using rotational thromboelastometry (ROTEM) and to compare coagulation states between sepsis and septic shock groups and between surviving and non-surviving groups.

MATERIALS AND METHODS

This prospective, observational, single-center study was conducted in the intensive care unit (ICU) of the University Medical Center Ho Chi Minh City, from 6/2020-12/2021. Patients aged ≥18 years with sepsis or septic shock according to the Sepsis-3 criteria were included. ROTEM and CCTs were concurrently performed within the first 24 h of ICU admission.

RESULTS

In total, 161 patients were enrolled. Based on ROTEM, 72.7 % of patients with sepsis/septic shock had coagulation disorders, including 25.5 % hypercoagulation, 54.7 % hypocoagulation, 13.6 % mixed hypo-hypercoagulation patterns, and 18.6 % hyperfibrinolysis. A common mixed disorder subtype was characterized by prolonged initial clotting time (CT) with subsequently increased clot firmness. Fibrinogen levels and maximum clot formation (MCF)-fibtem were strongly correlated (rho = 0.73, p < 0.05). Hypocoagulation was observed more in the septic shock group than in the sepsis group. Compared to survivors, non-survivors had more prolonged CT-extem.

CONCLUSIONS

ROTEM could identify hypocoagulability, hypercoagulability, mixed hypo-hypercoagulability patterns, and hyperfibrinolysis in patients with sepsis/septic shock. Elevated MCF-fibtem and elevated fibrinogen levels were notably common and strongly correlated. The septic shock group had more hypocoagulation than the sepsis group. Lastly, non-survivors had more prolonged CT-extem than survivors.

The Utility of NATEM Assay in Predicting Bleeding Risk in Critically Ill Neonates

We aimed to investigate the hemostatic status of diseased neonates using nonactivated rotational thromboelastometry (ROTEM) assay (NATEM) assay and, in addition, to evaluate the discriminative power of NATEM parameters in predicting the risk of bleeding in critically ill neonates and compare it to that of EXTEM (extrinsically activated ROTEM) parameters. This cohort study included 158 consecutive, critically ill neonates with presumed sepsis, perinatal hypoxia, or respiratory distress syndrome. The EXTEM and NATEM assays were performed on the first day of disease onset. The neonatal bleeding assessment tool was used to record and assess clinical bleeding events on the day of ROTEM analysis. Several EXTEM and NATEM ROTEM parameters differed between neonates with and without clinical bleeding events, indicating a hypo-coagulable state in neonates with clinical bleeding. NATEM parameters had comparable predictive performance for clinical bleeding events with EXTEM parameters for clotting time, clot formation time (CFT), A10 (clot amplitude at 10minutes), maximum clot firmness, lysis index at 60minutes, and maximum clot elasticity (p>0.05). However, NATEM A20, A30, and α angle demonstrated better predictive ability than EXTEM A20, A30, and α angle, respectively (p<0.05). A NATEM CFT value ≥147seconds presented 95.2% sensitivity (95% confidence interval [CI]: 76.1-99.8%) and 65.6% specificity (95% CI: 57.1-73.5%) to detect neonates with clinical bleeding, while a NATEM A10 value ≤42mm had 80.8% sensitivity (95% CI: 71.8-85.9%) and 76.0% specificity (95% CI: 52.8-91.7%) to detect neonates with clinical bleeding events. The NATEM assay has shown remarkable sensitivity in predicting bleeding in critically ill neonates, exceeding EXTEM performance in some selected parameters. The incorporation of NATEM test parameters in predictive models for neonatal hemorrhage seems promising.

Fibrinolysis shutdown and elevated D-dimer levels have high prognostic capacity for postoperative thromboembolic complications in patients with bone tumors

Surgical resection of malignant bone tumors is associated with a high risk of venous thromboembolism (VTE). The purpose of this study was to evaluate the association between rotational thromboelastometry (ROTEM) parameters and VTE following oncologic resections, and to evaluate their prognostic capacity for this complication. A prospective observational study was conducted including 113 patients who underwent surgical resection of malignant bone tumors. ROTEM analysis and conventional coagulation studies were performed preoperatively and on the 2nd postoperative day, while patients were followed for the development of VTE. Logistic regression was used to assess the association between ROTEM parameters and occurrence of VTE. The area under the receiver operating characteristic curve (AUC), sensitivity and specificity were calculated as measures of discrimination and predictive accuracy. Fourteen patients (12.4%) developed symptomatic VTE. Development of VTE was associated with shortened INTEM CFT (Odds Ratio [OR] 0.90, 95% Confidence Interval [CI] 0.84 - 0.96, p = 0.004), higher INTEM A10 (OR 1.21, 95% CI 1.07 - 1.36, p = 0.002), higher INTEM MCF (OR 1.22, 95% CI 1.08 - 1.37, p = 0.001) and higher INTEM LI60 (OR 2.10, 95% CI 1.38 - 3.21, p = 0.001). An INTEM LI60 value indicative of fibrinolysis shutdown (≥ 98%) had the best predictive accuracy for VTE (AUC = 0.887, 95% CI 0.824 - 0.951, sensitivity = 100%, specificity = 67.0%), higher than that of D-dimer levels (p = 0.028). ROTEM parameters were promising predictors of symptomatic VTE. Fibrinolysis shutdown as reflected by ROTEM LI60 and high D-dimer levels can aid the identification of high-risk patients. Future studies should evaluate whether the addition of ROTEM findings to an expanded risk-assessing model can improve the predictive capacity and provide better guidance in thromboprophylaxis.

Sepsis-Induced Coagulopathy: An Update on Pathophysiology, Biomarkers, and Current Guidelines

Significant cross talk occurs between inflammation and coagulation. Thus, coagulopathy is common in sepsis, potentially aggravating the prognosis. Initially, septic patients tend to exhibit a prothrombotic state through extrinsic pathway activation, cytokine-induced coagulation amplification, anticoagulant pathways suppression, and fibrinolysis impairment. In late sepsis stages, with the establishment of disseminated intravascular coagulation (DIC), hypocoagulability ensues. Traditional laboratory findings of sepsis, including thrombocytopenia, increased prothrombin time (PT) and fibrin degradation products (FDPs), and decreased fibrinogen, only present late in the course of sepsis. A recently introduced definition of sepsis-induced coagulopathy (SIC) aims to identify patients at an earlier stage when changes to coagulation status are still reversible. Nonconventional assays, such as the measurement of anticoagulant proteins and nuclear material levels, and viscoelastic studies, have shown promising sensitivity and specificity in detecting patients at risk for DIC, allowing for timely therapeutic interventions. This review outlines current insights into the pathophysiological mechanisms and diagnostic options of SIC.

Assessment of agreement between EXTEM and NATEM thromboelastometry measurement assays in critically ill neonates

OBJECTIVES

To investigate the agreement between the EXTEM and NATEM measurements.

METHODS

In this retrospective observational study, EXTEM and NATEM analyses were performed on blood samples from 162 ill neonates, providing 324 paired measurements. The agreement between EXTEM and NATEM measurements was evaluated by the nonparametric spearman's rank correlation to assess the correlation between the paired measurements, by the Bland-Altman analysis for the graphical presentation of the agreement, and by the Deming regression model to assess the significance of the agreement. The agreement between the two methods for the detection of bleeding events was determined by kappa statistic.

RESULTS

Strong correlations were found between EXTEM and NATEM measurements for A10, MCF. The Bland-Altman plots showed good agreement for A10, MCF, LI60, and alpha angle parameters, while CT showed a nearly linear slope indicating that bias increased with the mean. The highest agreement for bleeding events was found for the A10 parameter (κ = 0.70, p < .001), while the lowest for the CT parameter (κ = 0.36, p = .94).

CONCLUSIONS

NATEM parameters that reflect clot firmness and fibrinolytic activity are strongly correlated with the corresponding EXTEM measurements with a good agreement between them, indicating that these two methods could be used interchangeably.

Neonatal Sepsis and Hemostasis

Neonatal sepsis is considered critical for a significant increase in neonatal morbidity and mortality among hospitalized neonates. Neonatal sepsis, in most cases, coexists with coagulopathy, which can prove to be life-threatening. Complex molecular and cellular systems are involved in the cross-talk between inflammation and hemostasis during sepsis. Disturbances in the regulating systems of the vascular endothelium, and platelet–endothelial and platelet–neutrophil interactions play a pivotal role in both inflammation and coagulation. This complex process is poorly understood in neonates. In addition to the developmental maturation of hemostasis and the immune response in neonatal sepsis, a cellular model of hemostasis during sepsis should be taken into account. This review focused on the molecular and cellular mechanisms underlying inflammation and hemostasis during neonatal sepsis, taking the developmental immune response and developmental hemostasis into account in order to provide future diagnostic approaches to be applied in everyday clinical settings. Regarding the diagnostic modalities, we briefly provide the limitations of the currently used conventional coagulation assays, focusing on viscoelastic tests and platelet flow cytometry.

Development and validation of a sepsis diagnostic scoring model for neonates with suspected sepsis

BACKGROUND

We aimed to develop and validate a diagnostic model for sepsis among neonates evaluated for suspected sepsis, by incorporating thromboelastometry parameters, maternal/neonatal risk factors, clinical signs/symptoms and laboratory results.

METHODS

This retrospective cohort study included 291 neonates with presumed sepsis, hospitalized in a NICU, from 07/2014 to 07/2021. Laboratory tests were obtained on disease onset and prior to initiating antibiotic therapy. Τhromboelastometry extrinsically activated (EXTEM) assay was performed simultaneously and Tοllner and nSOFA scores were calculated. Sepsis diagnosis was the outcome variable. A 10-fold cross-validation least absolute shrinkage and selection operator logit regression procedure was applied to derive the final multivariable score. Clinical utility was evaluated by decision curve analysis.

RESULTS

Gestational age, CRP, considerable skin discoloration, liver enlargement, neutrophil left shift, and EXTEM A10, were identified as the strongest predictors and included in the Neonatal Sepsis Diagnostic (NeoSeD) model. NeoSeD score demonstrated excellent discrimination capacity for sepsis and septic shock with an AUC: 0.918 (95% CI, 0.884-0.952) and 0.974 (95% CI, 0.958-0.989) respectively, which was significantly higher compared to Töllner and nSOFA scores.

CONCLUSIONS

The NeoSeD score is simple, accurate, practical, and may contribute to a timely diagnosis of sepsis in neonates with suspected sepsis. External validation in multinational cohorts is necessary before clinical application.

Hemostasis in neonatal ECMO

Extracorporeal membrane oxygenation (ECMO) is a life-saving support for cardio-respiratory function. Over the last 50 years, the extracorporeal field has faced huge technological progress. However, despite the improvements in technique and materials, coagulation problems are still the main contributor to morbidity and mortality of ECMO patients. Indeed, the incidence and survival rates of the main hemorrhagic and thrombotic complications in neonatal respiratory ECMO are relevant. The main culprit is related to the intrinsic nature of ECMO: the contact phase activation. The exposure of the human blood to the non-endothelial surface triggers a systemic inflammatory response syndrome, which chronically activates the thrombin generation and ultimately leads to coagulative derangements. Pre-existing illness-related hemostatic dysfunction and the peculiarity of the neonatal clotting balance further complicate the picture. Systemic anticoagulation is the management's mainstay, aiming to prevent thrombosis within the circuit and bleeding complications in the patient. Although other agents (i.e., direct thrombin inhibitors) have been recently introduced, unfractionated heparin (UFH) is the standard of care worldwide. Currently, there are multiple tests exploring ECMO-induced coagulopathy. A combination of the parameters mentioned above and the evaluation of the patient's underlying clinical context should be used to provide a goal-directed antithrombotic strategy. However, the ideal algorithm for monitoring anticoagulation is currently unknown, resulting in a large inter-institutional diagnostic variability. In this review, we face the features of the available monitoring tests and approaches, mainly focusing on the role of point-of-care (POC) viscoelastic assays in neonatal ECMO. Current gaps in knowledge and areas that warrant further study will also be addressed.

The use of thromboelastography (TEG) and rotational thromboelastometry (ROTEM) in neonates: a systematic review

"Developmental hemostasis" refers to the dynamic process of gradual hemostatic maturation. Conventional coagulation tests seem to fail to accurately depict the in vivo hemostasis, while viscoelastic tests, thromboelastography (TEG), and rotational thromboelastometry (ROTEM) appear very promising as they provide insight more rapidly and accurately into the hemostatic potential. We systematically reviewed the literature in PubMed to examine the use of TEG and ROTEM in neonates. Our search yielded 34 studies, of which 18 concerned healthy neonates and 16 sick neonates. These viscoelastic tests have shown accelerated initiation of coagulation, increased clot strength, and increased fibrinolysis in healthy neonates compared to children and adults. Cord blood leads to a hypercoagulable state as compared to whole blood when testing is performed with TEG. Pre-term neonates have a more hypocoagulable profile, but balanced hemostasis, related to term neonates, that evolves to a more procoagulant phenotype over the first month of life. Critically ill neonates exhibit a more hypocoagulable profile as compared to healthy neonates. TEG and ROTEM have shown predictive value for bleeding events in critically ill neonates and neonates undergoing cardiopulmonary bypass or therapeutic hypothermia.Conclusion: TEG and ROTEM need to become part of the standard coagulation assessment in clinical settings in which hemostatic abnormalities are involved, as they seem to provide more rapid and accurate information regarding the hemostatic profile of the neonates. Their predictive value for bleeding events in critically ill neonates could lead to a more targeted therapy optimizing utilization of blood products. What is Known: • Conventional coagulation tests seem to fail to accurately depict the in vivo hemostasis. • TEG and ROTEM delineate more rapidly and accurately the hemostatic potential. What is New: • TEG and ROTEM have shown predictive value for bleeding events. • TEG and ROTEM may lead to a more targeted transfusion therapy optimizing utilization of blood products.

Fibrinolytic Impairment and Mortality in Pediatric Septic Shock: A Single-Center Prospective Observational Study

OBJECTIVES

Fibrinolytic shutdown is associated with poor prognosis in adult sepsis, but data in the pediatric population are sparse. This study aimed to identify the association between impaired fibrinolysis and mortality in pediatric septic shock.

DESIGN

A prospective, observational study conducted between August 2019 and August 2020.

SETTING

PICU at a pediatric tertiary hospital in Hanoi, Vietnam.

PATIENTS

Fifty-six pediatric patients who met septic shock criteria were enrolled.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Conventional coagulation tests and rotational thromboelastometry were performed at diagnosis. The fibrinolytic activity on extrinsic pathway thromboelastometry was negatively correlated with the Vasoactive-Inotropic Score at 24 hours post-PICU admission, peak lactate level during the first 24 hours, Pediatric Logistic Organ Dysfunction-2 score, and Pediatric Risk of Mortality-III score (all p < 0.05). Compared with patients with nonovert disseminated intravascular coagulation, dysfunction of less than two organs, and who survived, patients with overt disseminated intravascular coagulation, dysfunction of greater than two organs, and who died showed significantly lower fibrinolytic activity, represented by significantly higher lysis indexes (%) and lower maximum lysis (%) (all p < 0.05). The threshold values for prediction of mortality were lysis index 60 minutes greater than 97.5 (area under the curve = 0.86; sensitivity = 73%; specificity = 90%), maximum lysis less than 6.5 (area under the curve = 0.83; sensitivity = 73%; specificity = 87%), and lysis index 45 minutes greater than 99.5 (area under the curve = 0.83; sensitivity = 73%; specificity = 85%). Hypofibrinolysis was associated with prolonged PICU length of stay in survivors and with early mortality in nonsurvivors.

CONCLUSIONS

Fibrinolytic shutdown in pediatric septic shock is associated with an increase in disease severity and mortality. This highlights the need for further investigations regarding whether fibrinolytic therapy improved the outcome of pediatric septic shock.

Thromboelastometry in Neonates with Respiratory Distress Syndrome: A Pilot Study

BACKGROUND

Although respiratory distress syndrome (RDS) constitutes a postnatal risk factor for bleeding and thromboembolic events in neonates, few studies have addressed this issue. We aimed to evaluate the hemostatic profile of neonates with RDS using rotational thromboelastometry (ROTEM).

METHODS

An observational study was conducted from November 2018 to November 2020 in the NICU of General Hospital of Nikaia "Aghios Panteleimon". Preterm and term neonates with RDS hospitalized in the NICU were included and EXTEM (tissue factor-triggered extrinsic pathway), INTEM (ellagic acid activated intrinsic pathway), and FIBTEM (with platelet inhibitor cytochalasin D) assays were performed at the onset of the disease.

RESULTS

A hypocoagulable profile was noted in neonates with RDS compared to controls, expressed as significant prolongation of EXTEM CT (clotting time) and CFT (clot formation time), lower EXTEM A10 (amplitude at 10 min), MCF (maximum clot firmness), and LI60 (lysis index). Furthermore, prolongation of INTEM CFT and FIBTEM CT, and decreased INTEM and FIBTEM A10 and MCF were found in neonates with RDS. Multivariable logistic regression analysis showed that RDS is an independent factor for the recorded alterations in ROTEM variables.

CONCLUSIONS

RDS is associated with a hypocoagulable profile and greater hyperfibrinolytic potential compared to healthy neonates.

The Safety and Efficacy of Tranexamic Acid in Oncology Patients Undergoing Endoprosthetic Reconstruction and a ROTEM-Based Evaluation of Their Hemostatic Profile: A Pilot Study

Simple Summary

Tranexamic acid can be an effective and safe way to reduce perioperative bleeding following an endoprosthetic reconstruction of a lower limb after a bone tumor resection. Tranexamic acid does not result in a complete shutdown of the fibrinolysis, supporting its safe use without increasing the risk of thromboembolic complications.

Abstract

Background: An endoprosthetic reconstruction in musculoskeletal oncology patients is associated with significant blood loss. The purpose of this study is to evaluate the safety and efficacy of tranexamic acid (TXA) for these patients and to assess any changes in their hemostatic profile using rotational thromboelastometry (ROTEM). Methods: A retrospective observational study was performed including 61 patients with primary or metastatic bone tumors who underwent surgery. Group A (n = 30) received both intravenous and local TXA whereas Group B (n = 31) was the control group. The primary outcomes were perioperative blood loss and blood unit transfusions and the secondary outcomes included the incidence of thromboembolic complications and a change in blood coagulability as reflected by ROTEM parameters. Results: The median difference in blood loss between the two groups was 548.5 mL, indicating a 29.2% reduction in the 72 h blood loss following TXA administration (p < 0.001). TXA also led to a reduced transfusion of 1 red blood cell (RBC) unit per patient (p < 0.001). The two groups had similar rates of thromboembolic complications (p = 0.99). The antifibrinolytic properties of TXA were confirmed by the significantly higher INTEM, FIBTEM and EXTEM LI60 (p < 0.001, p = 0.005 and p < 0.001, respectively) values in the TXA group. Conclusion: Tranexamic acid was associated with a significant reduction in perioperative blood loss and transfusion requirements without a complete shutdown of the fibrinolysis. Larger studies are warranted to assess the frequency of these outcomes in musculoskeletal oncology patients.

The Procoagulant Effect of COVID-19 on the Thrombotic Risk of Patients with Hip Fractures Due to Enhanced Clot Strength and Fibrinolysis Shutdown

Introduction: Coronavirus disease 2019 (COVID-19) in patients with hip fractures is associated with increased incidence of venous thromboembolism (VTE). The purpose of this study was to evaluate the hemostatic alterations of COVID-19 that are associated with a higher thrombotic risk using rotational thromboelastometry (ROTEM). Methods: A retrospective observational study was performed including 20 COVID-19 patients with hip fractures. To compare the coagulopathy of patients with mild COVID-19 and hip fractures with the coagulopathy associated with each of these two conditions separately, we used two previously recruited groups of patients; 198 hip fracture patients without COVID-19 and 21 COVID-19 patients without hip fractures. The demographics, clinical parameters, conventional coagulation parameters and ROTEM findings of the three groups were analyzed and compared. Results: COVID-19 hip fracture patients had higher amplitude of clot firmness at 10 min (p < 0.001), higher alpha angle (p < 0.001), higher lysis index at 60 min (p < 0.001), and shorter clot formation time (p < 0.001) than non-COVID-19 hip fracture patients, indicating increased clot strength and impaired fibrinolysis due to COVID-19. The value of lysis index at 60 min (99%) in COVID-19 patients with hip fractures was consistent with fibrinolysis shut down. Multivariable linear regression analysis further confirmed that COVID-19 resulted in increased amplitude of clot firmness at 10 min (p < 0.001), increased maximum clot firmness (p < 0.001), increased lysis index at 60 min (p < 0.001) and increased alpha angle (p < 0.001), but significantly shortened clot formation time (p < 0.001). Discussion: The higher thrombotic risk in COVID-19 patients with hip fractures is characterized by increased clot strength and fibrinolysis shutdown, as shown by ROTEM findings. Further prospective studies are warranted to evaluate the need for modification of thromboprophylaxis to balance the hemostatic derangements of COVID-19 patients with hip fractures.

Rotational Thromboelastometry in Neonates Admitted to a Neonatal Intensive Care Unit: A Large Cross-sectional Study

The aim of the present study was to assess the coagulation profile in neonatal critical illness using rotational thromboelastometry (ROTEM), and to investigate its association with disease severity and its potential prognostic role in this clinical setting. Over a period of 67 months (July 2014-February 2020) 423 critically ill neonates with confirmed or suspected sepsis, perinatal hypoxia, or respiratory distress syndrome, hospitalized in our neonatal intensive care unit were included in the study. Demographic, clinical, and laboratory data were recorded on admission day and arterial blood was analyzed on ROTEM analyzer using the standard extrinsically activated rotational thromboelastometry assay (EXTEM). Neonatal illness severity scores (Modified NEOMOD [Neonatal Multiple Organ Dysfunction] and SNAPPE [Score for Neonatal Acute Physiology with Perinatal Extension]) were calculated at the same time as ROTEM analysis. Mortality during in-hospital stay was the main outcome measure. Multivariable analyses showed that a 10 mm decrease in EXTEM clot amplitude recorded at 10 minutes (A10) is significantly associated with a higher mortality (odds ratio [OR] = 1.69, 95% confidence interval [CI]: 1.33-2.08). Higher modified NEOMOD (OR = 1.36, 95% CI: 1.26-1.47) and higher SNAPPE scores (OR = 1.06, 95% CI: 1.04-1.08) were also associated with increased mortality. The CT and A10 variables demonstrated the best prognostic performance among the EXTEM parameters for mortality (area under the curve [AUC] = 0.78; 95% CI: 0.69-0.86 and AUC = 0.76; 95% CI: 0.66-0.85, respectively), showing an optimal cut-off CT ≥63 seconds and A10 ≤37 mm. Using optimal cut-off values of the EXTEM parameters for prediction of mortality, neonates with CT ≥63 seconds were 7.4 times more likely to die (OR = 7.40, 95% CI: 3.50-15.65), while neonates with A10 ≤37 mm were 5.8 times more likely to die (OR = 5.88, 95% CI: 2.94-12.50). An EXTEM hypocoagulable profile on disease onset was shown to be an independent risk factor for in-hospital mortality in neonatal critical illness.

Hemostatic Challenges in Neonates

The neonatal hemostatic system is strikingly different from that of adults. Among other differences, neonates exhibit hyporeactive platelets and decreased levels of coagulation factors, the latter translating into prolonged clotting times (PT and PTT). Since pre-term neonates have a high incidence of bleeding, particularly intraventricular hemorrhages, neonatologists frequently administer blood products (i.e., platelets and FFP) to non-bleeding neonates with low platelet counts or prolonged clotting times in an attempt to overcome these "deficiencies" and reduce bleeding risk. However, it has become increasingly clear that both the platelet hyporeactivity as well as the decreased coagulation factor levels are effectively counteracted by other factors in neonatal blood that promote hemostasis (i.e., high levels of vWF, high hematocrit and MCV, reduced levels of natural anticoagulants), resulting in a well-balanced neonatal hemostatic system, perhaps slightly tilted toward a prothrombotic phenotype. While life-saving in the presence of active major bleeding, the administration of platelets and/or FFP to non-bleeding neonates based on laboratory tests has not only failed to decrease bleeding, but has been associated with increased neonatal morbidity and mortality in the case of platelets. In this review, we will present a clinical overview of bleeding in neonates (incidence, sites, risk factors), followed by a description of the key developmental differences between neonates and adults in primary and secondary hemostasis. Next, we will review the clinical tests available for the evaluation of bleeding neonates and their limitations in the context of the developmentally unique neonatal hemostatic system, and will discuss current and emerging approaches to more accurately predict, evaluate and treat bleeding in neonates.

The haemostatic profile in critically ill COVID-19 patients receiving therapeutic anticoagulant therapy: An observational study

Hypercoagulability and thrombosis remain a challenge in severe coronavirus disease 2019 (COVID-19) infections. Our aim is to investigate the hemostatic profile of critically ill COVID-19 patients on therapeutic anticoagulant treatment.Forty one patients were enrolled into the study. We recruited 11 consecutive, COVID-19, patients who received therapeutic anticoagulant treatment on intensive care unit (ICU) admission. Disease severity indexes, biochemical, hematological and haemostatic parameters, endogenous thrombin potential (ETP), plasminogen activator inhibitor-1 (PAI-1) activity and extrinsically activated rotational thromboelastometry assay (EXTEM) were recorded on days 1, 3, 7. We also enrolled 9 ICU non-COVID-19, 21 non-ICU COVID-19 patients and 20 healthy blood donors as control populations.Critically ill COVID-19 patients demonstrated a more hypercoagulable and hypofibrinolytic profile related to those with COVID-19 mild illness, based on EXTEM amplitude at 10 min (A10), maximum clot firmness (MCF) and lysis index at 60 min (LI60) variables (p = 0.020, 0.046 and 0.001, respectively). Similarly, a more hypercoagulable state was detected in COVID-19 ICU patients related to non-COVID-19 ICU patients based on A10 and MCF parameters (p = 0.03 and 0.04, respectively). On the contrary, ETP and EXTEM (clotting time) CT values were similar between patients with severe and mild form of the COVID-19 infection, probably due to anticoagulant treatment given.Critically ill COVID-19 patients showed a hypercoagulable profile despite the therapeutic anticoagulant doses given. Due to the small sample size and the study design, the prognostic role of the hypercoagulability in this clinical setting remains unknown and further research is required in order to be assessed.

COVID-19 Infection-Related Coagulopathy and Viscoelastic Methods: A Paradigm for Their Clinical Utility in Critical Illness

Hypercoagulability and thrombosis remain a challenge to diagnose and treat in severe COVID-19 infection. The ability of conventional global coagulation tests to accurately reflect in vivo hypo- or hypercoagulability is questioned. The currently available evidence suggests that markedly increased D-dimers can be used in identifying COVID-19 patients who may need intensive care unit (ICU) admission and close monitoring or not. Viscoelastic methods (VMs), like thromboelastography (TEG) and rotational thromboelastometry (ROTEM), estimate the dynamics of blood coagulation. The evaluation of coagulopathy by VMs in severe COVID-19 infection seems an increasingly attractive option. Available evidence supports that COVID-19 patients with acute respiratory failure suffer from severe hypercoagulability rather than consumptive coagulopathy often associated with fibrinolysis shutdown. However, the variability in definitions of both the procoagulant profile and the clinical outcome assessment, in parallel with the small sample sizes in most of these studies, do not allow the establishment of a clear association between the hypercoagulable state and thrombotic events. VMs can effectively provide insight into the pathophysiology of coagulopathy, detecting the presence of hypercoagulability in critically ill COVID-19 patients. However, it remains unknown whether the degree of coagulopathy can be used in order to predict the outcome, establish a diagnosis or guide anticoagulant therapy.