Dr. Prism Schneider

• Orthopaedic Surgery
• Thrombosis
• Intimate Partner Violence
• Evaluating Individual Cancer-associated Thrombosis Mechanisms to Inform Personalized Thromboprophyla

Dr. Schneider’s research interests involve understanding the cellular and systemic inflammatory response to injury, including trauma-induced coagulopathy and post-traumatic joint contractures, clinical trials for optimizing surgical outcomes, and using advanced imaging to study the micro-architecture of fracture healing. She also has a particular interest in identifying and assisting patients who are injured due to violence in the home. Dr. Schneider has completed several multi-centre randomized controlled trials in collaboration with the Canadian Orthopaedic Trauma Society, in order to define surgical indications following injury and to determine the optimal surgical techniques to help improve patient outcomes. Dr. Schneider’s trauma-induced coagulopathy research program is funded by the Orthopaedic Research and Education Foundation, the Canadian Institutes for Health Research, and the Canadian Foundation for Innovation. She is an emerging leader in injury-related coagulopathy and her program aims to use a precision medicine approach to prevention of venous thromboembolism.

Evaluating Individual Cancer-associated Thrombosis Mechanisms to Inform Personalized Thromboprophyla

Patients with cancer are at risk of developing pathologic or impending orthopaedic fractures, called metastatic bone disease (MBD), and require surgical intervention. However, cancer, advanced age, and the need for surgery have been identified as risk factors for developing venous thromboembolism (VTE), which includes life-threatening pulmonary embolism and debilitating deep vein thromboses. VTE is the second leading cause of death for patients with cancer. Despite thromboprophylaxis, up to 15% of patients experience VTE and there is limited consensus regarding guidelines for pharmacologic thromboprophylaxis after major orthopaedic surgery. In addition, there is bleeding risk and substantial cost associated with using blood thinners. Therefore, there is a need to better understand who is at increased risk for blood clots, what medication is best, and for how long to prescribe for, in order to balance blood clot prevention with bleeding risk. VTE risk is highly individualized and dependent on cancer type, disease burden, surgical insult, and cancer therapies; therefore, a precision medicine approach to thromboprophylaxis is needed.

Thrombelastography (TEG) technology is a point-of-care assay that uses a small sample of blood to evaluate a person's clotting ability and can identify hypercoagulable states. Maximal amplitude values (MA; measure of clot strength) from TEG analysis is used to quantify duration of hypercoagulability and increased VTE risk. Moreover, TEG and multi-modal analysis can be used to evaluate platelet function and activation to characterize the diverse processes underlying the hypercoagulable state. My research involves following a prospective cohort of MBD patients who require surgery for pathologic fractures. Patients enrolled in the study undergo serial TEG, platelet procoagulant membrane dynamics assessment, coagulation and inflammatory marker measurement, proteomics analysis, and surveillance lower extremity compression ultrasound.

My research has demonstrated that VTE risk in MBD patients is based on platelet-mediated hypercoagulability that varies across individuals and often persists beyond thromboprophylaxis use. Moreover, the degree, duration, and mechanisms of postoperative hypercoagulability may vary among MBD patients. My research aims to evaluate the mechanisms driving cancer-associated thrombosis to inform personalized risk stratification and thromboprophylaxis strategies. The results of the study will be directly translatable to clinical practice and may reveal novel drug targets to reduce VTE-associated morbidity and mortality.