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

Hemostatic Status of Neonates with Perinatal Hypoxia, Studied via NATEM in Cord Blood Samples

BACKGROUND

Perinatal hypoxia may result in coagulation dysfunction. Diminished blood flow or oxygen to the fetus/neonate during the perinatal period can cause bone marrow and liver function impairment, leading to thrombocytopenia, impaired synthesis of clotting and fibrinolytic factors, and increased destruction of platelets in the small blood vessels. The goal of the present study was to evaluate the hemostatic status of newborns with perinatal hypoxia via the non-activated thromboelastometry (NATEM) assay in cord blood samples.

METHODS

134 hypoxic neonates born in our maternity unit over a 1.5-year period were enrolled in this observational cohort study, and 189 healthy neonates served as the control group. Participation in the study was voluntary and parents signed informed consent prior to recruitment. Demographic and clinical data were recorded on admission, and the NATEM method was performed on cord blood samples. The following NATEM values were evaluated: clotting time (CT), alpha angle (α-angle), clot formation time (CFT), clot amplitude at 5 and 10 min. (A5, A10), maximum clot firmness (MCF), clot lysis index at 60 min. after CT (LI60), and maximum clot elasticity (MCE). Statistical analysis was conducted utilizing the SAS for Windows 9.4 software platform.

RESULTS

Neonates with perinatal hypoxia exhibited decreased fibrinolytic potential in comparison to healthy neonates, as indicated by increased LI60, and this difference was statistically significant (LΙ60: 94 (92-96) Vs 93 (91-95), p value = 0.0001). There were no statistically significant differences noted among the remaining NATEM variables.

CONCLUSION

Our findings indicate decreased fibrinolytic potential in hypoxic neonates in comparison to healthy neonates, suggesting that NATEM could serve as an effective tool for promptly identifying hemostasis dysfunction in this group of neonates.

Bleeding Scoring Systems in Neonates: A Systematic Review

We conducted a systematic review aiming to summarize the data on the current hemorrhage prediction models and evaluate their potential for generalized application in the neonatal population. The electronic databases PubMed and Scopus were searched, up to September 20, 2023, for studies that focused on development and/or validation of a prediction model for bleeding risk in neonates, and described the process of model building. Nineteen studies fulfilled the inclusion criteria for the present review. Eighteen bleeding risk prediction models in the neonatal population were identified, four of which were internally validated, one temporally and one externally validated. The existing prediction models for neonatal hemorrhage are mostly based on clinical variables and do not take into account the clinical course and hemostatic profile of the neonates. Most studies aimed at predicting the risk of intraventricular hemorrhage (IVH) reflecting the fact that IVH is the most frequent and serious bleeding complication in preterm neonates. A justification for the study sample size for developing the prediction model was given only by one study. Prediction and stratification of risk of hemorrhage in neonates is yet to be optimized. To this end, qualitative standards for model development need to be further improved. The assessment of the risk of bleeding incorporating platelet count, coagulation parameters, and a set of relevant clinical variables is crucial. Large, rigorous, collaborative cohort studies are warranted to develop a robust prediction model to inform the need for transfusion, which is a fundamental step towards personalized transfusion therapy in neonates.

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.

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.

Hemostasis in Neonates with Perinatal Hypoxia—Laboratory Approach: A Systematic Review

Birth asphyxia, with an estimated prevalence of 1 to 6 per 1,000 live births, may lead to multiorgan dysfunction due to impaired oxygen and/or blood supply to various organ systems, including the hemostatic system. Coagulopathy, a common complication of perinatal asphyxia, has been described since the 1960s. The aim of this study was to systematically review the literature for records on the use of hemostasis tests in the evaluation of coagulation disorders, in neonates who had suffered from perinatal hypoxia or asphyxia. We identified published studies by searching PubMed and Scopus, up until April 2022. The literature search retrieved 37 articles fulfilling the inclusion criteria of the review. According to the bibliography, thrombocytopenia is commonly associated with perinatal hypoxia/asphyxia. The thrombocytopenia is usually described as mild and platelets return to normal levels by the 10th day of life. Additionally, hypoxic neonates usually present with a hypocoagulable profile, as reflected by the prolongation of standard coagulation tests, including prothrombin time, activated partial thromboplastin time, and international normalized ratio, findings commonly associated with disseminated intravascular coagulation, and by the reduction of the levels of the physiologic inhibition of coagulation system. A few studies thus far using ROTEM/TEG in hypoxic neonates have come to the same conclusion as well; hypoxic newborns seem to be characterized by a hypocoagulable profile compared with healthy neonates. It should be emphasized, however, that standard coagulation tests provide only a rough estimation of the true bleeding or thrombotic risk of hypoxic neonates. On the contrary, viscoelastic methods seem to be more precise in the early detection of hemostasis disorders in the neonatal population. However, until now, there was uncertainty as to the most appropriate coagulation assays for diagnosis and management of coagulation derangement in neonates with perinatal hypoxia indicating the need for further research on this field.

The impact of maternal smoking during pregnancy on hemostatic profile of neonates using thromboelastometry (ROTEM). A pilot observational study

INTRODUCTION

In adults, the negative effect of smoking on hemostasis has been well established. Contrarily, data regarding the hemostatic status of neonates exposed to tobacco during pregnancy are limited. This study aimed to investigate the influence of antenatal tobacco exposure on the hemostatic profile of neonates using Thromboelastometry (ROTEM).

METHODS

This observational study included 92 healthy full-term neonates born in the maternity department of our hospital over a 5-year period. The neonates were categorized in 2 groups: neonates born to mothers who reported smoking during the entire pregnancy and neonates born to non-smoking mothers. Neonates were matched 1:1 with regards to gestational age, delivery mode, and gender. ROTEM EXTEM assay was performed on the 2nd-3rd day of life and clotting time (CT); clot formation time (CFT); clot amplitude recorded at 10 and 30 min (A10, A30); a angle (a^o); maximum clot firmness (MCF, mm); lysis index at 30 and 60 min (LI30, LI60, %); maximum clot elasticity (MCE), were measured.

RESULTS

Neonates with antenatal exposure to tobacco had shorter CT (p < 0.001) and CFT (p = 0.035), higher A10 (p = 0.043), A30 (p = 0.028) and MCE (p = 0.028) compared to those not exposed to tobacco during pregnancy. The multivariable regression analysis adjusted for gestational age, gender, birth weight and delivery mode showed that maternal tobacco use during pregnancy is associated with an accelerated activation of coagulation in neonates expressed by shorter EXTEM CT values (coefficient: -8.68, 95%,CI: -13.51--3.85, p = 0.001) while no association was found with the remaining ROTEM parameters.

DISCUSSION

Smoking during pregnancy results in a hypercoagulable profile of neonates, expressed by shorter ROTEM CT. Antenatal exposure to tobacco appears to be an aggravating factor for the hemostatic status of neonates.

The Hypercoagulable Profile of Patients with Bone Tumors: A Pilot Observational Study Using Rotational Thromboelastometry

Introduction: A detailed evaluation of the malignancy-associated coagulopathy (MAC) in surgical patients with bone tumors may allow for more effective thromboprophylactic measures. The purpose of this study was to assess the perioperative hemostatic changes in patients with bone tumors, using rotational thromboelastometry (ROTEM). Methods: An observational study was performed, including 50 patients with bone tumors who underwent oncologic resection and 30 healthy controls, matched for age and gender. The preoperative and postoperative laboratory evaluation of coagulation in both groups included conventional coagulation tests and a ROTEM analysis. The results of the conventional coagulation tests and the ROTEM analysis were compared between the two groups. Results: The results of the conventional coagulation tests were comparable between the tumor patients and the healthy controls. However, compared to the healthy adults, the tumor patients had lower CT (p < 0.001) and CFT (p < 0.001) values suggesting a rapid induction of the coagulation cascade, elevated A10 (p < 0.001) and MCF (p < 0.001) values indicating a higher clot strength and platelet activation, and elevated LI60 (p < 0.001) values indicating hypofibrinolysis in patients with bone tumors. The multiple linear regression analysis (controlling for potential confounding factors) confirmed the independent association of bone tumors with these hemostatic changes. Conclusions: Our results support the advantageous use of a ROTEM in patients with bone tumors over conventional coagulation tests because the qualitative changes in the hemostatic profile of these patients that can be detected by a ROTEM analysis cannot be identified by conventional tests. The ROTEM results indicate that the hypercoagulable state in patients with bone tumors is caused by the malignancy-associated activation of the coagulation cascade, platelet activation, and hypofibrinolysis.

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.

The Non-Activated Thromboelastometry (NATEM) Assay's Application among Adults and Neonatal/Pediatric Population: A Systematic Review

The non-activated thromboelastometry (NATEM) assay is a point-of-care assay that can provide a comprehensive insight into the actual hemostatic mechanism. However, there are very limited data about its use in clinical practice. The aim of this study was to systematically review the literature for any data regarding the use of NATEM in several clinical settings. A systematic review of PubMed and Scopus databases was conducted through 20 January 2022 for studies evaluating the use of the NATEM assay in different clinical settings. The literature search yielded a total of 47 publications, 30 of which met the eligibility criteria for this review. Evaluation of NATEM’s detecting ability for hemostasis disorders is limited in the literature. The results of the included studies indicate that NATEM seems to be a sensitive method for the detection of hyperfibrinolysis and may have an advantage in the diagnosis of hemostatic disorders. It could be more informative than the other ROTEM assays for detecting changes in coagulation parameters in patients who receive anticoagulants. However, the reported outcomes are highly varying among the included studies. NATEM has a high sensitivity to detect hypo- or hypercoagulability and provides a detailed insight into the whole hemostatic process from clot formation to clot breakdown. It could be a useful technique in variable fields of medicine, not only in adults, but also in pediatric and neonatal populations, to guide different hemostatic treatments and predict coagulation disorders or mortality/morbidity; this issue remains to be further investigated.

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.

Hemostatic Evaluation With Viscoelastic Coagulation Monitor: A Nicu Experience

BACKGROUND

Viscoelastic coagulation tests provide valuable information in neonatal intensive care units (NICUs), but the lack of reference intervals still limits their decision-making power according to gestational age. The aim of the present study is to evaluate the hemostasis of a cohort of full-term (FT) and late-preterm (LP) infants using the viscoelastic coagulation monitor (VCM®) system, a new portable device that uses untreated whole blood.

METHODS

An observational study was performed to identify non-coagulopathic FT and LP infants admitted to III° level NICU (January 2020 to December 2021) with a VCM test in the first 72 h of life.

RESULTS

Forty-five patients were enrolled, 26 FT and 19 LP. No statistical differences in hemostatic parameters were observed between FT and LP nor between stable and unstable neonates. Clotting time (CT) was positive correlated with PT (p = 0.032), not with aPTT (p = 0.185). From linear regression, platelet resulted associated with: clot formation time (CTF, p = 0.003), alpha angle (Alpha, p = 0.010), amplitude at 10 (A10, p = 0.001), amplitude at 20 min (A20, p < 0.001), maximum clot firmness (MCF, p < 0.001); and fibrinogen was associated with: A10 (p = 0.008), A20 (p = 0.015) and MCF (p = 0.024). Compared to the adult reference population, neonates showed shorter CT (mean (SD): 5.3 (1.4) vs. 7.0 (0.9) min, p < 0.001), CFT (2.4 (0.7) vs. 2.8 (0.6) minutes, p < 0.001) and higher Alpha (60.8 (6.3) vs. 55 (5)°, p < 0.001). In addition, the neonatal cohort showed an early transient difference in amplitude and fibrinolysis, as follows: A10 (28.0 (5.0) vs. 26 (4) VCM units, p =0.004), A20 (34.8 (5.0) vs. 33 (4) VCM units, p =0.012), and LI30 (99.8 (0.5) vs. 99 (1)%, p <0.001).

CONCLUSIONS

The viscoelastic profile of FT and LP infants assessed with VCM showed a hemostatic competence characterized by accelerated coagulation and clot formation time, in line with other viscoelastic techniques. VCM system provides promising applications in the NICU setting.

Comparative Performance of Four Established Neonatal Disease Scoring Systems in Predicting In-Hospital Mortality and the Potential Role of Thromboelastometry

BACKGROUND

To compare the prognostic accuracy of the most commonly used indexes of mortality over time and evaluate the potential of adding thromboelastometry (ROTEM) results to these well-established clinical scores.

METHODS

The study population consisted of 473 consecutive term and preterm critically-ill neonates. On the first day of critical illness, modified Neonatal Multiple Organ Dysfunction (NEOMOD) scoring system, Score for Neonatal Acute Physiology (SNAP II), Perinatal extension of SNAP (SNAPPE), and SNAPPE II, were calculated and ROTEM standard extrinsically activated (EXTEM) assay was performed simultaneously. Time-to-event methodology for competing-risks was used to assess the performance of the aforementioned indexes in predicting in-hospital mortality over time. Time-dependent receiver operator characteristics curves for censored observation were compared across indexes. The addition of EXTEM parameters to each index was tested in terms of discrimination capacity.

RESULTS

The modified NEOMOD score performed similarly to SNAPPE. Both scores performed significantly better than SNAP II and SNAPPE II. Amplitude recorded at 10 min (A10) was the EXTEM parameter most strongly associated with mortality (A10 < 37 mm vs. ≥37 mm; sHR = 5.52; p < 0.001). Adding A10 to each index apparently increased the prognostic accuracy in the case of SNAP II and SNAPPE II. However, these increases did not reach statistical significance.

CONCLUSION

Although the four existing indexes considered showed good to excellent prognostic capacity, modified NEOMOD and SNAPPE scores performed significantly better. Though larger studies are needed, adding A10 to well-established neonatal severity scores not including biomarkers of coagulopathy might improve their prediction of in-hospital mortality.