Rotational Thromboelastometry (ROTEM)-guided Diagnosis and Management of Amniotic Fluid Embolism

There has been a significant interest in the last decade in the use of viscoelastic tests (VETs) to determine the hemostatic competence of bleeding patients. Previously, common coagulation tests (CCTs) such as the prothrombin time (PT) and partial thromboplastin time (PTT) were used to assist in the guidance of blood component and hemostatic adjunctive therapy for these patients. However, the experience of decades of VET use in liver failure with transplantation, cardiac surgery, and trauma has now spread to obstetrical hemorrhage and congenital and acquired coagulopathies. Since CCTs measure only 5 to 10% of the lifespan of a clot, these assays have been found to be of limited use for acute surgical and medical conditions, whereby rapid results are required. However, there are medical indications for the PT/PTT that cannot be supplanted by VETs. Therefore, the choice of whether to use a CCT or a VET to guide blood component therapy or hemostatic adjunctive therapy may often require consideration of both methodologies. In this review, we provide examples of the relative indications for CCTs and VETs in monitoring hemostatic competence of bleeding patients.

“…Fibrinogen replacement targets FIBTEM MCF to prevent coagulopathy. 9 133 164 165 166 167 168 170 171 172 173 174 175 176 177 178 179 180…”

Section: Relative Pathologic Indications For Ccts Versus Vetsmentioning

confidence: 99%

Section: Relative Pathologic Indications For Ccts Versus Vetsmentioning

confidence: 99%

The Choice between Plasma-Based Common Coagulation Tests and Cell-Based Viscoelastic Tests in Monitoring Hemostatic Competence: Not an either–or Proposition

Bunch

Berquist

Ansari

et al. 2022

“…Use of POC-VHA has been described in several case reports. 64 65 66 POC-VHA results have enabled early diagnosis during maternal collapse, differentiating amniotic fluid embolus (AFE) from other causes of maternal collapse such as pulmonary embolus. Prompt POC-VHA algorithm-guided treatment has probably contributed to successful maternal outcomes.…”

Section: Incidence Of Coagulation Abnormalities In Pphmentioning

confidence: 99%

“…The appropriate use of POC-VHA to inform FFP transfusion is unknown, partly due to the very low incidence of PT/aPTT abnormalities during PPH. 49 53 Early FFP to treat significant hypofibrinogenemia is also unlikely to be helpful because of its low fibrinogen content of around 2 g/L and the very large amounts of fibrinogen sometimes required to correct PPH-related hypofibrinogenemia, sometimes up to 16 g. 58 65 78 79 There are no studies that have been specifically designed to test possible thresholds for clot initiation time in the ROTEM or TEG and neither the Extem CT nor the Kaolin R time appears to be useful in identifying abnormalities in PT/aPTT or directing FFP transfusion. 52 77 The Kaolin K parameter may be useful if the PT/aPTT is >1.5× the upper reference range value, but this requires further evaluation.…”

Section: Poc-vha Pph Algorithmsmentioning

confidence: 99%

The Role of Thromboelastography during the Management of Postpartum Hemorrhage: Background, Evidence, and Practical Application

Collis

Bell

2022

Postpartum hemorrhage (PPH) is a common cause of significant maternal morbidity and mortality that can be associated with coagulopathy, especially hypofibrinogenemia. There is interest in point-of-care viscoelastic hemostatic assays (POC-VHA) in PPH because prompt knowledge of coagulation status can aid diagnosis, identify cases of severe coagulopathy, and allow ongoing monitoring during rapid bleeding. The incidence of coagulopathy in most cases of PPH is low because of the procoagulant state of pregnancy, including raised fibrinogen levels of around 4 to 6 g/L. A Clauss fibrinogen of >2 g/L or POC-VHA equivalent has been found to be adequate for hemostasis during PPH. POC-VHA has been used successfully to diagnose hypofibrinogenemia (Clauss fibrinogen of ≤2 g/L) and guide fibrinogen treatment which has reduced bleed size and complications of massive transfusion. There are uncertainties about the use of POC-VHA to direct fresh frozen plasma and platelet administration during PPH. Several POC-VHA algorithms have been used successfully incorporated in the management of many thousands of PPHs and clinicians report that they are easy to use, interpret, and aid decision making. Due to the relative cost of POC-VHA and lack of definitive data on improving outcomes, these devices have not been universally adopted during PPH.

“…25 27 VET-guided resuscitation with blood products and hemostatic agents successfully manages AFE DIC-like coagulopathy. 35 36…”

Section: Management Of Bleeding Patientsmentioning

confidence: 99%

Role of Viscoelastic and Conventional Coagulation Tests for Management of Blood Product Replacement in the Bleeding Patient

Matkovic

Lindholm

2022

An important aim of viscoelastic testing (VET) is to implement transfusion algorithms based on coagulation test results to help reduce transfusion rates and improve patient outcomes. Establishing a rapid diagnosis and providing timely treatment of coagulopathy is the cornerstone of management of severely bleeding patients in trauma, postpartum hemorrhage, and major surgery. As the nature of acute bleeding and trauma leads to an unstable and tenuous physiologic state, conventional coagulation tests (CCTs) are too slow to diagnose, manage, and also course correct any hemostatic abnormalities that accompany an acute critical illness. Viscoelastic point-of-care tests strongly correlate with results from standard laboratory tests but are designed to enable clinicians to make timely, informed bleeding management decisions when time to intervene is critical. These assays provide an individualized and goal-oriented approach to patient blood management and are increasingly becoming involved in transfusion algorithms. The scope of this review aims to evaluate the current literature on VETs and their impact on actionable outputs in clinical decision making and their relationship to CCT.