TEG Use in Children Undergoing Procedures With High Anticipated Blood Loss

Thromboelastography (TEG) and Intraoperative Coagulation Management of Pediatric Patients Undergoing Procedures With High Anticipated Blood Loss

The research team proposes a prospective, observational study to better understand how TEG can be useful in guiding clinical practice in the Main OR for subject's undergoing high transfusion risk surgeries.

Intraoperatively, transfusion of blood products is frequently required to restore oxygen carrying capacity, perfusion and improve coagulation. Both under and over transfusion pose significant risks, particularly to pediatric patients with small starting intravascular volumes. Thromboelastography (TEG) is a validated method of dynamically assessing intraoperative coagulopathy via functional assay. However, while FDA approved and widely used in the adult setting, TEG is not commonly utilized in the setting of bleeding pediatric patients.

Recently, TEG has been made available at BCH for clinical purposes and is being used solely in the cardiac surgery setting. The investigators aim to provide TEG data for non-cardiac pediatric surgical cases with a high risk of intraoperative blood loss in order to assess the impact of this tool on intraoperative management.

Intraoperatively, transfusion of blood products is frequently required to restore oxygen carrying capacity, perfusion and improve coagulation. Both under and over transfusion pose significant risks, particularly to pediatric patients with small starting intravascular volumes. Thromboelastography (TEG) is a type of Viscoelastic testing (ROTEM is another example) and is a validated point of care method of dynamically assessing intraoperative coagulopathy via functional assay. It provides more useful information than the commonly used laboratory values of INR, PT, PTT and Fibrinogen. However, while FDA approved and widely used in the adult setting, TEG is not commonly utilized in the setting of bleeding pediatric patients. Recently, TEG has been made available at Boston Children's Hospital (BCH) for clinical purposes exclusively in the cardiac surgery setting. The investigators aim to provide TEG data for general main operating room (MOR) pediatric surgical cases with a high risk of intraoperative blood loss in order to assess the impact of this tool on intraoperative management of the bleeding patient.

Primary Aim:

Assess the efficacy of providing real time viscoelastic testing (TEG) to anesthesiologists managing of pediatric patients with hemostatic bleeding undergoing procedures with high historical rates of blood transfusions. The outcome will be perioperative (intraoperative and within 24 H postoperative) hemostatic blood product transfusion (type of blood product and volume mL/g) within specific high blood loss surgical procedures. Data will be compared to matched cohorts using historical data from the same surgery types available in the Department of Anesthesia Blood Management Database.

Secondary Aim:

Assess the feasibility of providing real time and interpreting TEG data in a busy, academic, pediatric main OR at relevant clinical time points. Pre-operative and post-operative surveys will be administered to clinicians to gauge interest and knowledge in using TEG.

Hypothesis

The hypothesis is that the availability of TEG to help the management of pediatric surgical patients at a high risk for blood loss will improve targeted transfusion management, decrease overall intraoperative blood product utilization, and decrease variability in care. This data may ultimately yield future BCH viscoelastic test-guided (VET) transfusion protocols allowing a goal-directed approach. Benefits from this approach might translate into:

I. less exposure of the pediatric patient to blood products, thereby reducing the inherent risks of transfusion such as transfusion reactions, blood product associated infections and TRALI/TACO II. a reduction in costs, and III. Identification of clinical processes, such as fibrinolysis, that might otherwise be missed, leading to specific interventions (e.g. use of antifibrinolytics).

Although different blood product transfusion algorithms have been described in different clinical settings, there are no current VET (TEG or ROTEM) protocols in use for pediatric MOR surgical patients at this single center. See Appendix A for both existing BCH massive hemorrhage guidelines (MHG) and a massive hemorrhage protocol (MHP) including VET guided care - published as a supplement to the 2019 Society for the advancement of blood management administrative and clinical standards for patient blood management programs publication6.

These VET MHG will be available to the providers to help diagnosis and guide hemostatic blood product transfusion management intraoperatively.

Inclusion Criteria:

• Pediatric patients undergoing non-cardiac surgery at BCH with a high likelihood of blood transfusion. Specifically these are defined as a surgery with greater than 25% likelihood of transfusion of any non-albumin blood product.
• Eligible surgeries include:
• spinal surgery
• laparotomy
• liver transplant
• craniofacial surgery
• esophageal atresia
• craniotomy/hemispherectomy
• major abdominal surgery
• major hip surgery
• major plastic surgery

Exclusion Criteria:

• Patients undergoing cardiac surgery or ECMO cannulation, as these surgeries are generally considered outside the scope of general pediatric surgery.
• Patients presenting for emergent surgery
• Patients undergoing surgeries off hours (between 8pm and 8 am), when TEG analysis is unobtainable