for a given clinical situation are limited in children due to the rarity of this diagnosis An individualized treatment plan for patients with additional thrombotic risk factors is appropriate DISORDERS OF HEMOSTASIS Goals of Treatment Achieving hemostasis in the setting of spontaneous or traumatic bleeding is paramount Additionally, taking appropriate preemptive steps prior to procedural intervention for patients with ongoing or potential hemorrhage is critical CLINICAL PEARLS AND PITFALLS Factor replacement is the primary goal in any hemophilia patient with suspected or known bleeding Measured levels of factor VIII and factor IX typically predict clinical severity; however, levels for other factor deficiencies including VII and XI not reliably correlate with bleeding phenotype Current Evidence The most common inherited bleeding disorders are VWD, factor VIII deficiency (hemophilia A), and factor IX deficiency (hemophilia B) These bleeding disorders are reviewed in more detail in the following sections Other rare inherited disorders include isolated defects or deficiencies in specific factor proteins which contribute to the initiation of clot formation such as factor II, factor V, factor VII, factor X, factor XI, proteins responsible for clot stabilization such as factor XIII, and proteins which counter the fibrinolytic pathway such as plasminogen activator inhibitor type-1 (PAI-1) Each of these deficiencies has a clinically variable phenotype This combined with their rarity has hindered the development of clinical practice guidelines for rare bleeding disorders Once a diagnosis is made, therapeutic decisions must be tailored to the individual patient based on bleeding severity and location Acquired defects of hemostasis are uncommon in the pediatric population, but consider these disorders in the setting of acute onset of an unexpected bleeding episode in the absence of any personal or family history of bleeding Among the more common acquired causes are DIC, which can arise in the setting of sepsis or severe trauma, uremia and drug-induced platelet dysfunction, and decreased factor synthesis due to liver disease and cholestasis Clinical Considerations Clinical Recognition Severe congenital disorders of hemostasis typically present during infancy Mild and moderate disorders may go undetected until later childhood or even adulthood when patients sustain a challenge that exceeds the capability of their hemostatic system, such as major surgery or trauma, invasive dental procedure or extraction, or menarche Emergency physicians may encounter patients who are referred for an abnormal coagulation laboratory result obtained by a primary care physician, often because of an expressed concern for bleeding or easy bruising, or because of a family history of a bleeding disorder Consider underlying coagulation disorders in patients who return with postoperative and traumatic bleeding that seems out of proportion to the clinical situation Infants may present to the ED with prolonged bleeding from the site of circumcision or the umbilical stump Older children may present with a pattern of mucosal bleeding including epistaxis or menorrhagia, or with deep muscle or joint bleeds, usually trauma associated Triage If a child presents with active bleeding, initial assessment should focus on the site and severity of hemorrhage and prioritize therapeutic interventions to achieve hemostasis Evidence of hemodynamic compromise should prompt rapid resuscitation efforts to reestablish circulating volume Consider the need for prompt surgical involvement if clinically indicated Clinical Assessment A detailed history of the patient’s prior bleeding events and a thorough family history are necessary to determine the level of concern for an underlying bleeding disorder Pertinent history includes: Are bleeding episodes related to mild–moderate trauma or procedures or they occur spontaneously? Is the bleeding typically a mucocutaneous pattern (e.g., epistaxis, oral bleeding, petechiae, easy bruising, GI bleeding, or menorrhagia)? Is there bleeding into the deep muscles or joints? Is there a history of poor wound healing? Are bleeding episodes more likely to occur hours versus days after a procedure or injury? Additionally, family history of responses to hemostatic challenges may suggest an inherited defect of hemostasis Mucocutaneous bleeding is usually associated with defects of primary hemostasis such as platelet count (see section on thrombocytopenia above) or dysfunction, or VWD Bleeding into deep muscles or joints, especially when spontaneous, is characteristic of hemophilia Poor wound healing or delayed bleeding following a procedure has been described with factor XI, factor XIII, and PAI-1 deficiencies A physical examination should focus on findings of active or recent bleeding including a careful HEENT and dermatologic examination Diagnostic Testing The initial screening laboratories to investigate for hemostatic abnormalities should include CBC, examination of the peripheral blood smear, prothrombin time (PT), and activated partial thromboplastin time (aPTT), von Willebrand panel, thrombin time (TT), and fibrinogen Save blood for additional assays of specific factors An approach to initial interpretation of these tests is presented in Figure 93.5 The CBC reveals the platelet count, aids in recognition of associated anemia resulting from bleeding, and reveals white blood cell count abnormalities that may suggest underlying sepsis or malignancy Review of a peripheral blood smear enables verification of the platelet count and also allows for visualization of platelet morphology, such as the presence of normal granulation necessary for platelet function Other elements seen on the peripheral smear may also yield clues to the underlying diagnosis such as RBC fragments seen with microangiopathic coagulopathy or peripheral blasts suggestive of an underlying hematologic malignancy The PT evaluates factors II, V, VII, X and fibrinogen, while aPTT evaluates factors II, V, VIII, IX, X, XI, and fibrinogen Factor XII deficiency will also prolong the aPTT but is not associated with a bleeding phenotype These initial tests can help emergency physicians narrow the differential diagnosis, but more extensive evaluation is usually needed to make a final diagnosis Such tests may include a von Willebrand panel, assays for specific factor levels, inhibitor assays, platelet function (aggregometry) studies; these tests are almost never available in real time for clinical use in an emergency department Fortunately, initial steps in management are not hindered by the lack of a precise diagnosis It is important to note that proper collection of the blood sample for these specialized coagulation studies is paramount for accurate results Samples that are drawn through heparinized indwelling catheters, overshaken, or not promptly processed often yield erroneous results Management Establishment of a specific hemostatic disorder diagnosis should not take precedence over the timely management of a serious bleeding episode Where applicable, use local measures such as pressure dressings and nasal packing, as well as other adjuncts such as estrogen with or without progesterone in the case of menorrhagia In cases of trauma in the setting of underlying disorder of hemostasis, multidisciplinary management is appropriate Agents useful for achieving hemostasis are reviewed in Table 93.2 Specific management strategies for treating VWD and hemophilia A and hemophilia B are detailed below Rare Inherited Coagulation Factor Deficiencies There are no clinical practice guidelines for managing the rare, inherited coagulation factor deficiencies, in part because of small patient numbers and in part due to the clinical heterogeneity of these disorders For patients with known deficiencies, implementation of their bleeding management plan or consultation with their hematologist is advised For severe bleeding episodes, major trauma, or an emergent operative procedure, replacement of the missing factor protein is generally advised For factors VII and XIII, recombinant products are available; plasma-derived protein concentrates are also available for these factors and for factor XI in some countries Cryoprecipitate contains concentrated quantities of factor XIII, fibrinogen, factor VIII, and VWF Fresh-frozen plasma may be used for any factor deficiency; however, large volumes of product are often required to achieve hemostatic levels If patients have primarily mucosal bleeding, antifibrinolytic therapies may provide sufficient hemostasis FIGURE 93.5 Approach to diagnosis of a bleeding disorder Disseminated Intravascular Coagulopathy Treatment of the inciting disease process is critical Therapy to correct the coagulopathy is appropriate in an actively bleeding patient; however, it provides only a temporary solution Infusion of platelets, fresh-frozen plasma, and cryoprecipitate (see Table 93.2 ) may be trialed to improve hemostasis; however, replacement therapy should not be continued if there is no clinical benefit The role of heparin therapy for DIC remains controversial and should only be initiated in consultation with a hematologist The use of agents such as antithrombin, rFVIIa, and direct thrombin inhibitors has been reported in the adult literature, but there are presently no data to support their use in the pediatric population with DIC ... hemostatic system, such as major surgery or trauma, invasive dental procedure or extraction, or menarche Emergency physicians may encounter patients who are referred for an abnormal coagulation laboratory... also prolong the aPTT but is not associated with a bleeding phenotype These initial tests can help emergency physicians narrow the differential diagnosis, but more extensive evaluation is usually... (aggregometry) studies; these tests are almost never available in real time for clinical use in an emergency department Fortunately, initial steps in management are not hindered by the lack of a