Chapter 059. Bleeding and Thrombosis (Part 5)

Epistaxis is a common symptom, particularly in children and in dry climates, and may not reflect an underlying bleeding disorder. However, it is the most common symptom in hereditary hemorrhagic telangiectasia and in boys with vWD. Clues that epistaxis is a symptom of an underlying bleeding disorder include lack of seasonal variation and bleeding that requires medical evaluation or treatment, including cauterization. Bleeding with eruption of primary teeth is seen in children with more severe bleeding disorders, such as moderate and severe hemophilia. It is uncommon in children with mild bleeding disorders. Patients with disorders of primary hemostasis (platelet...
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Chapter 059. Bleeding and Thrombosis (Part 5) Chapter 059. Bleeding and Thrombosis (Part 5) Epistaxis is a common symptom, particularly in children and in dryclimates, and may not reflect an underlying bleeding disorder. However, it is themost common symptom in hereditary hemorrhagic telangiectasia and in boys withvWD. Clues that epistaxis is a symptom of an underlying bleeding disorderinclude lack of seasonal variation and bleeding that requires medical evaluation ortreatment, including cauterization. Bleeding with eruption of primary teeth is seenin children with more severe bleeding disorders, such as moderate and severehemophilia. It is uncommon in children with mild bleeding disorders. Patientswith disorders of primary hemostasis (platelet adhesion) do have increasedbleeding after dental cleanings and other procedures that involve gummanipulation. Menorrhagia is defined quantitatively as a loss of >80 cc of blood percycle, based on blood loss required to produce iron-deficiency anemia. Acomplaint of heavy menses is subjective and has a poor correlation with excessiveblood loss. Predictors of menorrhagia include bleeding resulting in iron-deficiencyanemia or a need for blood transfusion, excessive pad or tampon use, menseslasting longer than 8 days, passage of clots, bleeding through protection, orflooding at night. Menorrhagia is a common symptom in women with underlyingbleeding disorders and is reported in the majority of women with vWD and factorXI deficiency and in symptomatic carriers of hemophilia A. Women withunderlying bleeding disorders are more likely to have other bleeding symptoms,including bleeding after dental extractions, postoperative bleeding, and postpartumbleeding, and are much more likely to have menorrhagia beginning at menarchethan women with menorrhagia due to other causes. Postpartum hemorrhage is a common symptom in women with underlyingbleeding disorders. This occurs most commonly in the first 48 h after delivery, butit may also be manifest by prolonged or excessive bleeding after discharge fromthe hospital. Women with a history of postpartum hemorrhage have a high risk ofrecurrence with subsequent pregnancies. Rupture of ovarian cysts withintraabdominal hemorrhage has also been reported in women with underlyingbleeding disorders. Tonsillectomy is a major hemostatic challenge, as intact hemostaticmechanisms are essential to prevent excessive bleeding from the tonsillar bed.Bleeding may occur early after surgery or after approximately 7 dayspostoperatively, with loss of the eschar at the operative site. Similar delayedbleeding is seen after colonic polyp resection by cautery. Gastrointestinal (GI)bleeding and hematuria are usually due to underlying pathology and procedures toidentify and treat the bleeding site should be undertaken, even in patients withknown bleeding disorders. vWD, particularly types 2 and 3, has been associatedwith angiodysplasia of the bowel and GI bleeding. Hemarthroses and spontaneous muscle hematomas are characteristic ofmoderate or severe congenital factor VIII or IX deficiency. They can also be seenin moderate and severe deficiencies of fibrinogen, prothrombin, and of factors V,VII, and X. Spontaneous hemarthroses occur rarely in other bleeding disordersexcept for severe vWD, with associated FVIII levels from another cause or even unmask a previously occult mild bleeding disordersuch as vWD. All NSAIDs, however, can precipitate gastrointestinal bleeding,which may be more severe in patients with underlying bleeding disorders. Theaspirin effect on platelet function as assessed by aggregometry can persist for upto 7 days, although it has frequently returned to normal by 3 days after the lastdose. The effect of other NSAIDs is shorter, as the inhibitor effect is reversedwhen the drug is removed. Many herbal supplements can impair hemostatic function (Table 59-2).Some have been more convincingly associated with a bleeding risk than others.Fish oil or concentrated omega 3 fatty acid supplements impair platelet activation.They alter platelet biochemistry to produce more PGI3, a more potent plateletinhibitor than prostacyclin (PGI2), and more thromboxane A3, a less potentplatelet activator than thromboxane A2. In fact, diets naturally rich in omega 3fatty acids can result in a prolonged bleeding time and abnormal plateletaggregation studies, but the actual associated bleeding risk is unclear. Vitamin Eappears to inhibit protein kinase C–mediated platelet aggregation and nitric oxideproduction. In patients with unexplained bruising or bleeding, it is prudent toreview any new medications or supplements and discontinue those that may beassociated with bleeding. Table 59-2 Herbal Supplements Associated with In ...