Viscoelastic monitoring in pediatric trauma: a survey of pediatric trauma society members

Thromboelastography and Its Use in Pediatric Trauma Patients

BACKGROUND/PURPOSE

Thromboelastography's (TEG's) use in pediatric trauma patients is not widely studied. Identifying clotting cascade defects can direct decision making regarding blood product transfusion.

METHODS

We performed a single-center retrospective review of all level 1 pediatric trauma patients. Data collected included demographics, diagnoses, Injury Severity Score, intensive care unit length of stay (ICU LOS), mortality, TEG values, and blood products received. We identified TEG values associated with mortality, ICU LOS, and need for blood product transfusion.

RESULTS

A total of 237 trauma 1 patients were identified. After exclusions, 148 patients were included for analysis. Most patients were below TEG transfusion cut points. Patients with elevated reaction time, K value, and fibrinolysis at 30 minutes had increased odds of mortality with odds ratios of 1.71 (95% confidence interval [CI], 1.22-2.40), 1.94 (95% CI, 1.23-3.05), and 1.15 (95% CI, 1.03-1.28), respectively. For ICU LOS, elevated reaction time, K value, and fibrinolysis at 30 minutes, α angle, and maximum amplitude demonstrated hazard ratios of 0.76 (95% CI, 0.65-0.88), 0.82 (95% CI, 0.64-1.0), 0.95 (95% CI, 0.88-0.99), 1.05 (95% CI, 1.02-1.08), and 1.04 (95% CI, 1.01-1.06), respectively. There was no association between TEG and blood product transfusion.

CONCLUSIONS

Coagulopathic patients based on TEG had higher mortality. All TEG values, as they moved toward transfusion-trigger cut points, were associated with increased mortality.

Admission maximum amplitude-reaction time ratio: Association between thromboelastography values predicts poor outcome in injured children

INTRODUCTION

Thromboelastography (TEG)-derived maximum amplitude-reaction time (MA-R) ratio that accounts for both hypocoagulable and hypercoagulable changes in coagulation is associated with poor outcomes in adults. The relationship between these TEG values and outcomes has not been studied in children.

METHODS

In a retrospective cohort study, a level I pediatric trauma center database was queried for children younger than 18 years who had a TEG assay on admission between 2016 and 2020. Demographics, injury characteristics, and admission TEG values were recorded. The MA-R ratio was calculated and divided into quartiles. Main outcomes included mortality, transfusion within 24 hours of admission, and thromboembolism. A logistic regression model was generated adjusting for age, Injury Severity Score, injury mechanism, admission shock, and Glasgow Coma Scale.

RESULTS

In total, 657 children were included, of which 70% were male and 75% had blunt mechanism injury. The median (interquartile range) age was 11 (4-14) years, the median (interquartile range) Injury Severity Score was10 (5-22), and in-hospital mortality was 7% (n = 45). Of these patients, 17% (n = 112) required transfusion. Most R and MA values were within normal limits. On unadjusted analysis, the lowest MA-R ratio quartile was associated with increased mortality (15% vs. 4%, 5%, and 4%, respectively; p < 0.001) and increased transfusion need (26% vs. 12%, 16%, and 13%, respectively; p = 0.002) compared with higher quartiles. In the logistic regression models, a low MA-R ratio was independently associated with increased in-hospital mortality (odds ratio [95% confidence interval], 4.4 [1.9-10.2]) and increased need for transfusion within 24 hours of admission (odds ratio [95% confidence interval], 2.0 [1.2-3.4]) compared with higher MA-R ratio. There was no association between MA-R ratio and venous thromboembolic events (venous thromboembolic event rate by quartile: 4%, 2%, 1%, and 3%).

CONCLUSION

Although individual admission TEG values are not commonly substantially deranged in injured children, the MA-R ratio is an independent predictor of poor outcome. Maximum amplitude-reaction time ratio may be a useful prognostic tool in pediatric trauma; validation is necessary.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level III.

Pediatric traumatic hemorrhagic shock consensus conference research priorities

BACKGROUND

Traumatic injury is the leading cause of death in children and adolescents. Hemorrhagic shock remains a common and preventable cause of death in the pediatric trauma patients. A paucity of high-quality evidence is available to guide specific aspects of hemorrhage control in this population. We sought to identify high-priority research topics for the care of pediatric trauma patients in hemorrhagic shock.

METHODS

A panel of 16 consensus multidisciplinary committee members from the Pediatric Traumatic Hemorrhagic Shock Consensus Conference developed research priorities for addressing knowledge gaps in the care of injured children and adolescents in hemorrhagic shock. These ideas were informed by a systematic review of topics in this area and a discussion of these areas in the consensus conference. Research priorities were synthesized along themes and prioritized by anonymous voting.

RESULTS

Eleven research priorities that warrant additional investigation were identified by the consensus committee. Areas of proposed study included well-designed clinical trials and evaluations, including increasing the speed and accuracy of identifying and treating hemorrhagic shock, defining the role of whole blood and tranexamic acid use, and assessment of the utility and appropriate use of viscoelastic techniques during early resuscitation. The committee recommended the need to standardize essential definitions, data elements, and data collection to facilitate research in this area.

CONCLUSION

Research gaps remain in many areas related to the care of hemorrhagic shock after pediatric injury. Addressing these gaps is needed to develop improved evidence-based recommendations for the care of pediatric trauma patients in hemorrhagic shock.

Pediatric traumatic hemorrhagic shock consensus conference recommendations

ABSTRACT

Hemorrhagic shock in pediatric trauma patients remains a challenging yet preventable cause of death. There is little high-quality evidence available to guide specific aspects of hemorrhage control and specific resuscitation practices in this population. We sought to generate clinical recommendations, expert consensus, and good practice statements to aid providers in care for these difficult patients.The Pediatric Traumatic Hemorrhagic Shock Consensus Conference process included systematic reviews related to six subtopics and one consensus meeting. A panel of 16 consensus multidisciplinary committee members evaluated the literature related to 6 specific topics: (1) blood products and fluid resuscitation for hemostatic resuscitation, (2) utilization of prehospital blood products, (3) use of hemostatic adjuncts, (4) tourniquet use, (5) prehospital airway and blood pressure management, and (6) conventional coagulation tests or thromboelastography-guided resuscitation. A total of 21 recommendations are detailed in this article: 2 clinical recommendations, 14 expert consensus statements, and 5 good practice statements. The statement, the panel's voting outcome, and the rationale for each statement intend to give pediatric trauma providers the latest evidence and guidance to care for pediatric trauma patients experiencing hemorrhagic shock. With a broad multidisciplinary representation, the Pediatric Traumatic Hemorrhagic Shock Consensus Conference systematically evaluated the literature and developed clinical recommendations, expert consensus, and good practice statements concerning topics in traumatically injured pediatric patients with hemorrhagic shock.

Rotational thromboelastometry in children presenting to an Australian major trauma centre: A retrospective cohort study

Objective

This retrospective cohort study aims to describe patterns of rotational thromboelastometry (ROTEM™) results in paediatric trauma following the implementation of a ROTEM‐guided critical bleeding algorithm and major haemorrhage protocol (MHP).

Methods

This retrospective observational study was conducted in a tertiary trauma hospital in Queensland, Australia, where point‐of‐care ROTEM was introduced for paediatric patients in 2014. All children aged less than 18 years who had a ROTEM test during their presentation between January 2014 and December 2017 for a traumatic injury were included in the dataset. Other children with a record in the hospital's trauma registry in the same period were also screened for blood product usage. Data were collected for frequency of ROTEM testing, pathology and ROTEM results, blood product and antifibrinolytic use along with injury related data. Compliance with recommended treatment thresholds for detected coagulopathy was also reviewed.

Results

A total of 1039 children were listed in the trauma registry, including 167 children having a ROTEM test for trauma. Factors significantly associated with having a ROTEM test were older age, higher injury severity score (ISS >12) and penetrating injury. A result exceeding a treatment threshold was returned for 122 (73.1%) of 167 children, with hyperfibrinolysis identified in 88 (52.6%) of 167 and hypofibrinogenaemia identified in 54 (32.3%) of 167. Adherence with the recommended treatments for those children where a treatment threshold was exceeded was low in this cohort.

Conclusion

The use of ROTEM‐guided blood component replacement is an emerging practice in children for both traumatic and non‐traumatic bleeding. Targeted replacement of identified coagulation defects guided by rapid point‐of‐care testing is an emerging alternative to fixed‐ratio‐based protocols. Further research is required to validate treatment thresholds in the paediatric population and further investigate the clinical outcomes for patients as a result of early correction of trauma‐induced coagulopathy.

Coagulation profiles and viscoelastic testing in multisystem inflammatory syndrome in children

OBJECTIVE

To characterize viscoelastic testing profiles of children with multisystem inflammatory syndrome in children (MIS-C).

METHODS

This single-center retrospective review included 30 patients diagnosed with MIS-C from March 1 to September 1, 2020. Thromboelastography (TEG) with platelet mapping was performed in 19 (63%) patients and compared to age- and sex-matched controls prior to cardiac surgery. Relationships between TEG parameters and inflammatory markers were assessed using correlation.

RESULTS

Patients with MIS-C had abnormal TEG results compared to controls, including decreased kinetic (K) time (1.1 vs. 1.7 minutes, p < .01), increased alpha angle (75.0° vs. 65.7°, p < .01), increased maximum amplitude (70.8 vs. 58.3 mm, p < .01), and decreased lysis in 30 minutes (Ly30) (1.1% vs. 3.7%, p = .03); consistent with increased clot formation rate and strength, and reduced fibrinolysis. TEG maximum amplitude was moderately correlated with erythrocyte sedimentation rate (ESR) (r = 0.60, p = .02), initial platelet count (r = 0.67, p < .01), and peak platelet count (r = 0.51, p = .03). TEG alpha angle was moderately correlated with peak platelet count (r = 0.54, p = .02). Seventeen (57%) patients received aspirin (ASA) and anticoagulation, five (17%) received only ASA, and three (10%) received only anticoagulation. No patients had a symptomatic thrombotic event. Six (20%) patients had a bleeding event, none of which was major.

CONCLUSIONS

Patients with MIS-C had evidence of hypercoagulability on TEG. Increased ESR and platelets were associated with higher clot strength. Patients were prophylactically treated with ASA or anticoagulation with no symptomatic thrombosis or major bleeding. Further multicenter study is required to characterize the rate of thrombosis and optimal thromboprophylaxis algorithm in this patient population.

Viscoelastic monitoring in trauma resuscitation

BACKGROUND

Traumatic injury results in both physical and physiologic insult. Successful care of the trauma patient depends upon timely correction of both physical and biochemical injury. Trauma-induced coagulopathy is a derangement of hemostasis and thrombosis that develops rapidly and can be fatal if not corrected. Viscoelastic monitoring (VEM) assays have been developed to provide rapid, accurate, and relatively comprehensive depictions of an individual's coagulation profile. VEM are increasingly being integrated into trauma resuscitation guidelines to provide dynamic and individualized guidance to correct coagulopathy.

STUDY DESIGN AND METHODS

We performed a narrative review of the search terms viscoelastic, thromboelastography, thromboelastometry, TEG, ROTEM, trauma, injury, resuscitation, and coagulopathy using PubMed. Particular focus was directed to articles describing algorithms for management of traumatic coagulopathy based on VEM assay parameters.

RESULTS

Our search identified 16 papers with VEM-guided resuscitation strategies in adult patients based on TEG, 12 such protocols in adults based on ROTEM, 1 protocol for children based on TEG, and 2 protocols for children based on ROTEM.

CONCLUSIONS

This review presents evidence to support VEM use to detect traumatic coagulopathy, discusses the role of VEM in trauma resuscitation, provides a summary of proposed treatment algorithms, and discusses pending questions in the field.

Use of viscoelastic monitoring and prothrombin complex concentrate in a paediatric patient with polytrauma and severe traumatic brain injury

Viscoelastic monitoring (VEM) tools, such as rotational thrombelastometry, have been used extensively to measure coagulopathy in adults but have received less attention in paediatric care. The presented case involves a 5-year-old boy who was brought to the emergency department after a motor vehicle collision with a Glasgow Coma Scale score of 6T and extensive injuries, including a subdural hematoma. VEM was used to monitor the patient's coagulopathy and to inform treatment measures by allowing real-time visualisation of the patient's coagulation status. VEM was additionally used to direct blood product replacement in preparation for neurosurgical intervention, and 4-factor prothrombin complex concentrate (PCC) was used to help reverse the coagulopathy. The patient underwent successful hemicraniectomy after improvement of his coagulopathy. In paediatrics, VEM and PCC are increasingly being used for post-trauma coagulopathy, and this case highlights their potential promise and the need for further research.

Rotational thromboelastometry predicts transfusion and disability in pediatric trauma

BACKGROUND

Trauma-induced coagulopathy seen on rotational thromboelastometry (ROTEM) is associated with poor outcomes in adults; however, this relationship is poorly understood in the pediatric population. We sought to define thresholds for product-specific transfusion and evaluate the prognostic efficacy of ROTEM in injured children.

METHODS

Demographics, ROTEM, and clinical outcomes from severely injured children (age, < 18 years) admitted to a Level I trauma center between 2014 and 2018 were retrospectively analyzed. Receiver operating characteristic curves were plotted and Youden indexes were calculated against the endpoint of packed red blood cell transfusion to identify thresholds for intervention. The ROTEM parameters were compared against the clinical outcomes of mortality or disability at discharge.

RESULTS

Ninety subjects were reviewed. Increased tissue factor-triggered extrinsic pathway (EXTEM) clotting time (CT) >84.5 sec (p = 0.049), decreased EXTEM amplitude at 10 minutes (A10) <43.5 mm (p = 0.025), and decreased EXTEM maximal clot firmness (MCF) <64.5 mm (p = 0.026) were associated with need for blood product transfusion. Additionally, EXTEM CT longer than 68.5 seconds was associated with mortality or disability at discharge.

CONCLUSION

Coagulation dysregulation on thromboelastometry is associated with disability and mortality in children. Based on our findings, we propose ROTEM thresholds: plasma transfusion for EXTEM CT longer than 84.5 seconds, fibrinogen replacement for EXTEM A10 less than 43.5 mm, and platelet transfusion for EXTEM MCF less than 64.5 mm.

LEVEL OF EVIDENCE

Prognostic, Level III; Therapeutic, Level IV.

Trauma induced clotting factor depletion in severely injured children: a single center observational study

Background

Coagulopathy following severe trauma contributes significantly to mortality. Impaired clotting factors have been observed in adult trauma patients, but in pediatric trauma victims their activity has not yet been investigated.

Methods

Sixteen pediatric trauma patients were evaluated according to the ISS and assigned to two cohorts. An additional control group (CO; n = 10) was formed. Routine coagulation parameters and the soluble clotting factors (F) were tested. Nonparametric data was analyzed using the Mann-Whitney U test. Results are reported as median and interquartile range.

Results

The ISS of severely (SI, n = 8) and mildly (MI, n = 8) injured children differed significantly (25 [19–28] vs. 5 [4–6]; p < 0.001). INR was elevated in the SI cohort only when compared to the CO (1.21 [1.04-1.58] vs. 0.96 [0.93-1.00]; p = 0.001). Differences between SI and MI were found for FII (67 [53-90] vs. 82 [76-114] %; p = 0.028), FV (76 [47-88] vs. 92 [82-99] %; p = 0.028), and FXIII (67 [62-87] vs. 90 [77-102] %; p = 0.021). Comparison of the SI with the CO (FII 122 [112-144] %; p < 0.001; FV 123 [100-142] %; p = 0.002; and FXIII 102 [79-115] %; p = 0.006) also revealed a reduction in the activity of these factors. Furthermore, fibrinogen (198 [80-242] vs. 296 [204-324] mg/dl; p = 0.034), FVII (71 [63-97] vs. 114 [100-152] %; p = 0.009), FIX (84 [67-103] vs. 110 [90-114] %; p = 0.043), and FX (70 [61-85] vs. 122 [96-140] %; p = 0.001) were reduced in the SI in comparison with the CO. Finally, FVIII was considerably, yet not significantly, increased in both patient cohorts (235 [91-320] % and 197 [164-238] %, respectively).

Conclusions

This study proves that children suffer a depletion of clotting factors following severe injury which basically reflects the findings for adult trauma patients. Attempts to correct the impaired clotting factor activity could be based on a specific hemostatic therapy involving administration of coagulation factors. Nevertheless, therapeutic implications need to be investigated in future studies.

Viscoelastic haemostatic assays and fibrinogen in paediatric acute traumatic coagulopathy: A comprehensive review

OBJECTIVE

Haemorrhage in paediatric trauma remains a significant cause of morbidity and mortality. Over recent years there has been increasing attention to the role of fibrinogen in traumatic haemorrhage and the association of low fibrinogen levels with poor patient outcomes. In addition, there has been a move towards using viscoelastic haemostatic assays (VHAs) to rapidly assess coagulation status and guide clinicians in the replacement of coagulation factors, including fibrinogen. In the paediatric population, there has been limited uptake of these principles and a paucity of data to support a change in practice. This paper summarises the available evidence in the published literature through a systematic review, presented in narrative format.

RESULTS

There is limited high-quality prospective data on the use of VHA in the management of acute traumatic coagulopathy in the paediatric population. While the use of fibrinogen early in major haemorrhage is becoming standard practice, there are currently no randomised prospective studies comparing fibrinogen concentrate to cryoprecipitate.

CONCLUSIONS

The early identification of hypo-fibrinogenemia and acute traumatic coagulopathy in paediatric trauma using VHA testing and subsequent early fibrinogen replacement with a concentrated off the shelf product is an attractive treatment option. However, there is currently insufficient high-level evidence to support the use of fibrinogen concentrate over cryoprecipitate in the paediatric trauma population. Pilot studies currently under way will go some way to addressing this important knowledge gap, and facilitate the design of larger definitive multi-centre randomised trials.

Pediatric trauma transfusion and cognitive aids

PURPOSE OF REVIEW

Trauma is the most common cause of pediatric mortality. Much of the research that led to life-saving interventions in adults, however, has not been replicated in the pediatric population. Children have important physiologic and anatomic differences from adults, which impact hemostasis and transfusion. Hemorrhage is a leading cause of death in trauma, and children have important differences in their coagulation profiles. Transfusion strategies, including the massive transfusion protocol and use of antifibrinolytics, are still controversial. In addition to the blood that is lost from the injury itself, trauma leads to inflammation and to a dysfunction in hemostasis, causing coagulopathy.

RECENT FINDINGS

In one study in which children suffered from mainly blast and penetrating injuries in a combat setting (PEDTRAX trial), the early administration of tranexamic acid was associated with decreased mortality. Some authors suggest that this result may not apply to blunt trauma, which is much more common in children in noncombat settings. Using thromboelastography to guide the administration of recombinant Factor VIIa has been done in selected cases and may represent a future avenue of research.

SUMMARY

This article explores new research from the past year in pediatric trauma, starting with the physiologic differences in pediatric red blood cells and coagulation profiles. We also looked at the dramatic change in thinking over the past decade in the tolerable level of anemia in critically ill pediatric patients, as well as scales for determining the need for massive transfusion and exploring if the concepts of damage control resuscitation apply to children. Other strategies, such as avoiding hypothermia, and the selective administration of antifibriniolytics, are important in pediatric trauma as well. Future research that is pediatric focused is needed for the optimal care of our youngest patients.

Recommendations on RBC Transfusion in Critically Ill Children With Nonlife-Threatening Bleeding or Hemorrhagic Shock From the Pediatric Critical Care Transfusion and Anemia Expertise Initiative

OBJECTIVES

To present the recommendations and supporting literature for RBC transfusions in critically ill children with bleeding developed by the Pediatric Critical Care Transfusion and Anemia Expertise Initiative.

DESIGN

Consensus conference series of international, multidisciplinary experts in RBC transfusion management of critically ill children.

METHODS

The panel of 38 experts developed evidence-based and, when evidence was lacking, expert-based clinical recommendations as well as research priorities for RBC transfusions in critically ill children. The bleeding subgroup included five experts. Electronic searches were conducted using PubMed, EMBASE, and Cochrane Library databases from 1980 to May 2017. Agreement was obtained using the Research and Development/UCLA Appropriateness Method. Results were summarized using the Grading of Recommendations Assessment, Development, and Evaluation method.

RESULTS

Transfusion and Anemia Expertise Initiative Consensus Conference experts developed a total of six recommendations focused on transfusion in the critically ill child with acute bleeding. In critically ill children with nonlife-threatening bleeding, we recommend giving a RBC transfusion for a hemoglobin concentration less than 5 g/dL, and be considered for a hemoglobin concentration between 5 and 7 g/dL. In critically ill children with hemorrhagic shock, we suggest that RBCs, plasma and platelets transfusion ratio between 2:1:1 to 1:1:1 until the bleeding is no longer life-threatening. We recommend future studies to develop physiologic and laboratory measures to indicate the need for RBC transfusions, and to determine if goal directed hemostatic resuscitation improves survival. Finally, we recommend future studies to determine if low titer group O whole blood is more efficacious and safe compared with reconstituted whole blood in children with hemorrhagic shock.

CONCLUSIONS

The Transfusion and Anemia Expertise Initiative Consensus Conference developed pediatric specific recommendations regarding RBC transfusion management in the critically ill child with acute bleeding, as well as recommendations to help guide future research priorities.