Point‐of‐care viscoelastic assay devices (rotational thromboelastometry and thromboelastography): a primer for surgeons

Abstract

Background: Bleeding is a common occurrence in surgery. Point-of-care testing with viscoelastic (VE) assays such as thromboelastography (TEG) and rotational thromboelastometry (ROTEM) has become more common place. TEG and ROTEM have the potential to guide management of coagulopathy. Many healthcare professionals still rely upon standard laboratory tests (SLTs) to manage a bleeding patient. It was our aim to investigate the literature surrounding management of the surgically bleeding patient via VE assays. Methods: Literature review of Embase, MEDLINE, PubMed and the Cochrane Library using 'TEG, ROTEM and surgery' search terms was conducted. Results: Through the literature search and reference lists reviewed by both authors, a total of 62 articles have been evaluated, 35 of these have been included in this review. Conclusion: VE assays are used most commonly during orthotopic liver transplantation, trauma, postpartum haemorrhage and cardiac surgery. Although the evidence is not overwhelming, we have identified recurrent themes where VE assays seem to be beneficial. VE assay use, especially when incorporated into an algorithm, appears to reduce blood product administration which in turn reduces cost and potential adverse events. They are quicker than SLTs and they can detect hyperfibrinolysis, the hallmark of coagulopathy, via in vivo clot analyses which SLTs are unable to do. Ultimately more randomized controlled trials are required.

Establishment of normal reference intervals in dogs using a viscoelastic point‐of‐care coagulation monitor and its comparison with thromboelastography

“…The VCM Vet analyzer could serve as a bedside test for the global assessment of coagulation in veterinary patients presenting with an array of hemostatic abnormalities. In human patients, one of the largest uses of viscoelastic tests is hemostasis monitoring in hypocoagulable patients requiring blood product transfusions secondary to trauma or invasive surgical procedures 9,10,11,12 . Viscoelastic tests in these patient populations have resulted in the use of fewer blood products and associated adverse events.…”

Intraoperative thromboelastography-guided transfusion in a patient with factor XI deficiency: A case report

“…Study results from trauma[ 7 ], liver transplant[ 8 ] and cardiac surgeries[ 9 ] have shown that the goal-directed allogeneic transfusion strategy is believed to provide better hemostatic competence. This was possibly due to the more timely administration of blood products such as plasma and platelets, which in turn resulted in less blood loss[ 3 ], reduced blood transfusion needs[ 10 ], lower costs, and fewer adverse events[ 11 ] in the TEG-guided transfusion group than in the conventional transfusion group. One study also suggested that TEG-guided transfusion could substantially affect patient outcomes, including length of hospital stay, odds of reoperation, and short-term mortality[ 9 ].…”

The Pathophysiology and Management of Hemorrhagic Shock in the Polytrauma Patient

“…A viscoelastic assay (VEA), by either thromboelastography (TEG) ( Figure 4 ) or rotational thromboelastometry (ROTEM), assesses several parameters of fibrin formation and HF and/or FS in whole blood [ 165 , 166 , 167 , 168 ]. VEA-based assessment of coagulation provides a rapid, integrated measure of clot formation and dissolution in blood compared to conventional coagulation tests (CCT) of individual coagulation pathways performed on prepared plasma and therefore in the absence of platelets and red cells.…”