Perioperatively acquired disorders of coagulation

Abstract

Purpose of review: To provide an overview of acquired coagulopathies that can occur in various perioperative clinical settings. Also described are coagulation disturbances linked to antithrombotic medications and currently available strategies to reverse their antithrombotic effects in situations of severe hemorrhage.

Recent findings: Recent studies highlight the link between low fibrinogen and decreased fibrin polymerization in the development of acquired coagulopathy. Particularly, fibrin(ogen) deficits are observable after cardiopulmonary bypass in cardiac surgery, on arrival at the emergency room in trauma patients, and with ongoing bleeding after child birth. Regarding antithrombotic therapy, although new oral anticoagulants offer the possibility of efficacy and relative safety compared with vitamin K antagonists, reversal of their anticoagulant effect with nonspecific agents, including prothrombin complex concentrate, has provided conflicting results. Specific antidotes, currently being developed, are not yet licensed for clinical use, but initial results are promising.

Summary: Targeted hemostatic therapy aims to correct coagulopathies in specific clinical settings, and reduce the need for allogeneic transfusions, thus preventing massive transfusion and its deleterious outcomes. Although there are specific guidelines for reversing anticoagulation in patients treated with antiplatelet agents or warfarin, there is currently little evidence to advocate comprehensive recommendations to treat drug-induced coagulopathy associated with new oral anticoagulants.

FIGURE 1

Points of action for oral anticoagulants on the coagulation cascade. Adapted with permission from [1].

FIGURE 2

Confocal imaging of clot formation. 3D visualization of a human blood clot: fibrin (light grey) was visualized via the detection of a fluorescein isothiocyanate-conjugated antifibrinogen antibody [3] added prior to the initiation of the coagulation process (star-tem/ex-tem). Platelets (dark grey) were stained using a fluorescently labeled wheat germ agglutinin [Real-time live confocal microscopy of a human blood sample stained with TMRM (light grey) and WGA (dark grey)]. The image was acquired by live confocal microscopy using an inverted microscope (Zeiss Observer.Z1; Zeiss, Oberkochen, Germany) in combination with a spinning disc confocal system (UltraVIEW VoX; Perkin Elmer, Waltham, MA). 1 Unit = 10.21 μm; objective: 63 × oil immersion, NA 1.42.

Box 1

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