Browsing by Author "Neal, Matthew D."

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    Hemorrhagic Resuscitation Guided by Viscoelastography in Far-Forward Combat and Austere Civilian Environments: Goal-Directed Whole-Blood and Blood-Component Therapy Far from the Trauma Center
    (MDPI, 2022-01-12) Lantry, James H.; Mason, Phillip; Logsdon, Matthew G.; Bunch, Connor M.; Peck, Ethan E.; Moore, Ernest E.; Moore, Hunter B.; Neal, Matthew D.; Thomas, Scott G.; Khan, Rashid Z.; Gillespie, Laura; Florance, Charles; Korzan, Josh; Preuss, Fletcher R.; Mason, Dan; Saleh, Tarek; Marsee, Mathew K.; Vande Lune, Stefani; Ayoub, Qamarnisa; Fries, Dietmar; Walsh, Mark M.; Emergency Medicine, School of Medicine
    Modern approaches to resuscitation seek to bring patient interventions as close as possible to the initial trauma. In recent decades, fresh or cold-stored whole blood has gained widespread support in multiple settings as the best first agent in resuscitation after massive blood loss. However, whole blood is not a panacea, and while current guidelines promote continued resuscitation with fixed ratios of blood products, the debate about the optimal resuscitation strategy-especially in austere or challenging environments-is by no means settled. In this narrative review, we give a brief history of military resuscitation and how whole blood became the mainstay of initial resuscitation. We then outline the principles of viscoelastic hemostatic assays as well as their adoption for providing goal-directed blood-component therapy in trauma centers. After summarizing the nascent research on the strengths and limitations of viscoelastic platforms in challenging environmental conditions, we conclude with our vision of how these platforms can be deployed in far-forward combat and austere civilian environments to maximize survival.
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    Immuno-Thrombotic Complications of COVID-19: Implications for Timing of Surgery and Anticoagulation
    (Frontiers Media, 2022-05-04) Bunch, Connor M.; Moore, Ernest E.; Moore, Hunter B.; Neal, Matthew D.; Thomas, Anthony V.; Zackariya, Nuha; Zhao, Jonathan; Zackariya, Sufyan; Brenner, Toby J.; Berquist, Margaret; Buckner, Hallie; Wiarda, Grant; Fulkerson, Daniel; Huff, Wei; Kwaan, Hau C.; Lankowicz, Genevieve; Laubscher, Gert J.; Lourens, Petrus J.; Pretorius, Etheresia; Kotze, Maritha J.; Moolla, Muhammad S.; Sithole, Sithembiso; Maponga, Tongai G.; Kell, Douglas B.; Fox, Mark D.; Gillespie, Laura; Khan, Rashid Z.; Mamczak, Christiaan N.; March, Robert; Macias, Rachel; Bull, Brian S.; Walsh, Mark M.; Surgery, School of Medicine
    Early in the coronavirus disease 2019 (COVID-19) pandemic, global governing bodies prioritized transmissibility-based precautions and hospital capacity as the foundation for delay of elective procedures. As elective surgical volumes increased, convalescent COVID-19 patients faced increased postoperative morbidity and mortality and clinicians had limited evidence for stratifying individual risk in this population. Clear evidence now demonstrates that those recovering from COVID-19 have increased postoperative morbidity and mortality. These data-in conjunction with the recent American Society of Anesthesiologists guidelines-offer the evidence necessary to expand the early pandemic guidelines and guide the surgeon's preoperative risk assessment. Here, we argue elective surgeries should still be delayed on a personalized basis to maximize postoperative outcomes. We outline a framework for stratifying the individual COVID-19 patient's fitness for surgery based on the symptoms and severity of acute or convalescent COVID-19 illness, coagulopathy assessment, and acuity of the surgical procedure. Although the most common manifestation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is COVID-19 pneumonitis, every system in the body is potentially afflicted by an endotheliitis. This endothelial derangement most often manifests as a hypercoagulable state on admission with associated occult and symptomatic venous and arterial thromboembolisms. The delicate balance between hyper and hypocoagulable states is defined by the local immune-thrombotic crosstalk that results commonly in a hemostatic derangement known as fibrinolytic shutdown. In tandem, the hemostatic derangements that occur during acute COVID-19 infection affect not only the timing of surgical procedures, but also the incidence of postoperative hemostatic complications related to COVID-19-associated coagulopathy (CAC). Traditional methods of thromboprophylaxis and treatment of thromboses after surgery require a tailored approach guided by an understanding of the pathophysiologic underpinnings of the COVID-19 patient. Likewise, a prolonged period of risk for developing hemostatic complications following hospitalization due to COVID-19 has resulted in guidelines from differing societies that recommend varying periods of delay following SARS-CoV-2 infection. In conclusion, we propose the perioperative, personalized assessment of COVID-19 patients' CAC using viscoelastic hemostatic assays and fluorescent microclot analysis.
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    Preventing Thrombohemorrhagic Complications of Heparinized COVID-19 Patients Using Adjunctive Thromboelastography: A Retrospective Study
    (MDPI, 2021-07-14) Bunch, Connor M.; Thomas, Anthony V.; Stillson, John E.; Gillespie, Laura; Khan, Rashid Z.; Zackariya, Nuha; Shariff, Faadil; Al-Fadhl, Mahmoud; Mjaess, Nicolas; Miller, Peter D.; McCurdy, Michael T.; Fulkerson, Daniel H.; Miller, Joseph B.; Kwaan, Hau C.; Moore, Ernest E.; Moore, Hunter B.; Neal, Matthew D.; Martin, Peter L.; Kricheff, Mark L.; Walsh, Mark M.; Medicine, School of Medicine
    BACKGROUND: The treatment of COVID-19 patients with heparin is not always effective in preventing thrombotic complications, but can also be associated with bleeding complications, suggesting a balanced approach to anticoagulation is needed. A prior pilot study supported that thromboelastography and conventional coagulation tests could predict hemorrhage in COVID-19 in patients treated with unfractionated heparin or enoxaparin, but did not evaluate the risk of thrombosis. METHODS: This single-center, retrospective study included 79 severely ill COVID-19 patients anticoagulated with intermediate or therapeutic dose unfractionated heparin. Two stepwise logistic regression models were performed with bleeding or thrombosis as the dependent variable, and thromboelastography parameters and conventional coagulation tests as the independent variables. RESULTS: Among all 79 patients, 12 (15.2%) had bleeding events, and 20 (25.3%) had thrombosis. Multivariate logistic regression analysis identified a prediction model for bleeding (adjusted R2 = 0.787, p < 0.001) comprised of increased reaction time (p = 0.016), decreased fibrinogen (p = 0.006), decreased D-dimer (p = 0.063), and increased activated partial thromboplastin time (p = 0.084). Multivariate analysis of thrombosis identified a weak prediction model (adjusted R2 = 0.348, p < 0.001) comprised of increased D-dimer (p < 0.001), decreased reaction time (p = 0.002), increased maximum amplitude (p < 0.001), and decreased alpha angle (p = 0.014). Adjunctive thromboelastography decreased the use of packed red cells (p = 0.031) and fresh frozen plasma (p < 0.001). CONCLUSIONS: Significantly, this study demonstrates the need for a precision-based titration strategy of anticoagulation for hospitalized COVID-19 patients. Since severely ill COVID-19 patients may switch between thrombotic or hemorrhagic phenotypes or express both simultaneously, institutions may reduce these complications by developing their own titration strategy using daily conventional coagulation tests with adjunctive thromboelastography.
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    Viscoelastic Hemostatic Assays: A Primer on Legacy and New Generation Devices
    (MDPI, 2022-02-07) Volod, Oksana; Bunch, Connor M.; Zackariya, Nuha; Moore, Ernest E.; Moore, Hunter B.; Kwaan, Hau C.; Neal, Matthew D.; Al-Fadhl, Mahmoud D.; Patel, Shivani S.; Wiarda, Grant; Al-Fadhl, Hamid D.; McCoy, Max L.; Thomas, Anthony V.; Thomas, Scott G.; Gillespie, Laura; Khan, Rashid Z.; Zamlut, Mahmud; Kamphues, Peter; Fries, Dietmar; Walsh, Mark M.; Medicine, School of Medicine
    Viscoelastic hemostatic assay (VHAs) are whole blood point-of-care tests that have become an essential method for assaying hemostatic competence in liver transplantation, cardiac surgery, and most recently, trauma surgery involving hemorrhagic shock. It has taken more than three-quarters of a century of research and clinical application for this technology to become mainstream in these three clinical areas. Within the last decade, the cup and pin legacy devices, such as thromboelastography (TEG® 5000) and rotational thromboelastometry (ROTEM® delta), have been supplanted not only by cartridge systems (TEG® 6S and ROTEM® sigma), but also by more portable point-of-care bedside testing iterations of these legacy devices (e.g., Sonoclot®, Quantra®, and ClotPro®). Here, the legacy and new generation VHAs are compared on the basis of their unique hemostatic parameters that define contributions of coagulation factors, fibrinogen/fibrin, platelets, and clot lysis as related to the lifespan of a clot. In conclusion, we offer a brief discussion on the meteoric adoption of VHAs across the medical and surgical specialties to address COVID-19-associated coagulopathy.