Thrombocytopenia is likely if petechiae are abundant or if clotted blood fails to retract within an hour or so. Conirmation is provided by a low platelet count. Ifsevere preeclampsia syndrome is comorbid, there may also be qualitative platelet dysfunction (Chap. 40, p. 719).
are standard coagulation tests. Prolongation may stem from very 256 ... .
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FIGURE 41 -30 Quantification offibrin-split products in various obstetrical syndromes that cause disseminated intravascular coagulation. AFLP = Acute fatty liver of pregnancy; HELLP = hemolysis, elevated liver enzyme levels, low platelet count. (Reproduced with permission from Cunningham FG, Nelson DB: Disseminated intravascular coagulation syndromes in obstetrics. Obstet Gynecol. 2015 Nov;126(5):999-101o1.) low fibrinogen concentrations, from appreciably reduced levels of the procoagulants needed to generate thrombin, or from large amounts of circulating fibrinogen-ibrin degradation products.
Thromboelastomety and thromboelastography are point-of care tests used as adjuncts to conventional laboratory studies (Abdul-Kadir, 2014). Their current role may serve to guide blood product replacement, discussed later (p. 791).
Using many of these tests, several organizations have attempted to establish a more uniform deinition of DIC. One is the International Society on Thrombosis and Haemostasis (ISTH) scoring system. The score is used ony ater a condition known to cause intravascular coagulation is identiied and is calculated using a combination of laboratory tests. Composite
ISTH-DIC scores <5 suggest nonovert DIC, whereas scores �5 are compatible with overt DIC. Other than one report of acute fatty liver of pregnancy, this scoring system has not been applied widely in obstetrics (Nelson, 2014).
To halt ongoing deibrination, prompt identiication and removal of the inciting source of the coagulopathy is a priority. With surgical incisions or extensive lacerations accompanied by severe hemorrhage, rapid replacement of procoagulants is usually indicated. Vigorous restoration and maintenance of the circulation to treat hypovolemia cannot be overemphasized. Adequate perfusion restores hepatic and endothelial synthesis of procoagulants and permits prompt removal of activated coagulation factors, ibrin, and ibrin degradation products by the reticuloendothelial system.
Aside from these fundamental steps, few other agents have proven soundly efective. Although seemingly counterintuitive, unfractionated heparin had been recommended but has now been abandoned. Other examples include use of antiibrinolytic agents-either tranexamic acid or epsilon-aminocaproic acid (micar) (American College of Obstetricians and Gynecologists, 2017 d; Pacheco, 2017). Currently, use of these two agents is not recommended because the ibrinolytic system is necessary for dissolution of widespread ibrin thromboses caused by generalized intravascular coagulation (Hunt, 2014). Discussed later (p. 790), recombinant factor VIla (rFVIIa) has been used to help control severe obstetrical hemorrhage from other causes. However, current clinical evidence is insuicient to make irm recommendations on its administration for obstetrical coagulopathies.