Term
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Definition
| inherited coagulation disorders from rare defects in single coagulation proteins; Hemophilia A-lacks Factor VIII; Hemophila B lacks Factor IX. the 2 X-linked disorders account for almost all known defects.Sex linked diseases where female is the carrier and males are affected. |
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Term
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Definition
| factor VIII deficiency known as classical hemphilia. acounts fo 85% of hempohilias.25/100,000 males are affected. Clinical bleeding correlates with degree of deficiency: <1% are severe hemopheliacs; 1-5% are moderate; amd >5% are mild. Most bleeding is associated with muscle or joint hemorrhage after trauma or surg. |
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Term
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Definition
| aPTT sensitive to factor deficiencies states 30% actvity. Pt with normal PT, but abnormal PTT have deficiencies in intrinsic factors (VIII,IX,XI, XII). need specific factor essay to Check VIII or IX to reveal appropriate defect. Except with hempohliaBm, both PT and PTT are prolonged. All pts with factor VIII deficiency should be tested for vonWillebrands disease. |
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Term
| Treatment of Hemophilia A |
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Definition
severe or moderate disease-tx with cryoprecipitate or Factor VIII concentrate. 2 sources of factor VIII are plasma derived and recombinant (nostimulation of immune response).
1 Unit factor VIII = 1 ml of pooled plasma. |
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Term
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Definition
depends on severity and desired plasma concentration; half life depends on body wt and plasma volume;
each unit factor VIII/Kg raises plasma level 2%.
Factor VIII units=desired-actual x .5 body wt. Give 50% of loading dose Q12 hrs until desired level reached. |
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Term
| Treatment plan for hemophiliacs undergoing surgery |
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Definition
Desired AFactor VIII levels should be 100% 1 hr prior to surg; 50% until wound healing begins; and 30% until healing complete. Dose 50Units/Kg, then Q12hr.peri-op and post-op plan must be in place pre-operatively so evaluation for factors established and needed doses are available.
Before surg:coag workup, test for inhibitors, stockpile therapeutic materials, and type RBC/crossmatch |
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Term
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Definition
| rich in factor VIII, fibrinigen, and vonWillebrands. Each bag contains 70-100 units of factor VIII/20ml, batches vary. |
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Term
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Definition
| DDAVP-used to tx mild factor VIII deficiencies. TRANSIENTLY increases factor VIII and vW to short bleeding time. DDAVP is a synthetic analog of the antidiuretic hormone vasopressin. Give IV over 15 min to treat mild bleeding episodes. Effects ^4-6fold and last 6 hrs. repeat Q12-24hrs. response attenuates with each dose. also available SC or transnasal (test dose). |
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Term
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Definition
| flushing, milf headache, increased HR, decreased BP, water retention may lead to severe hyponatremia (SIADH) DDAVP also increases plasminogen activator (Given with aminocaproic acid to inhibit potential fibrinolysis) |
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Term
| Treatment of inhibotors (antibodies) to factor VIII and IX |
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Definition
Should be suspected when calculated dose does not result in desired increase in factor level.
Treatment:reducce inhibitors with immunosuppresent therapy (cyclophosphamide), gamma-globulin, plasmaphoresis, or by tolerance with high doses or frequent administration of factors. |
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Term
| Hemophilia-acute bleeding or during surgery. |
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Definition
pts with low titers <5BU/ml-give double usual dose of factor.
pts with higher titer >10BU/ml give PCC (prothrombin complex conc) or APCC activated prothrombin complex conc.
Porcine factor VIII usual dose 50-75 units/kg Q12. alternative is recominant factor VIIa |
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Term
| Hemophilia B-factor IX deficiency |
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Definition
| Christmas factor-discovered in 1947 by accident. |
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Term
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Definition
| one of several varient of factor IX def.; Characterized by a long PT, most B pts are normal. Pt has the IX molecule, but not the protein for normal coagulation. believed that the abnormal protein interfers with factor VII-tissue factor activation of factor X which prolongs PT. |
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Term
| treatment of hemophilia B |
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Definition
highly purified factor IX plasma concentrate is tx of choice. 1/2 life 24 hrs, with normal hemostasis occurs at plasma levels of 10-25%.
Each unit Factor IX in infused/Kg increases factor IX 1%. |
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Term
| vonWillebrands disease-a glycoprotein that complexes with factor VIII |
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Definition
most common inheritable coagulopathy.
Caused by abnormality, qualitative, or quantitative of vW factor which results in both abnormal platelet function and defective plasma clotting. vWF has duel role in heostasis-facilitates platelet adhesion to injured vessel wall and servesas a carrier for factor VIII in plasma. vWF referred to as ristocetin cofactor. High molecular wt vWF more effective than factor VIII products because they have low molecular wt vWF |
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Term
| vonWillebrands presentation |
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Definition
mucosal bleeding, easy bruising, menorrhea, post-surgical bleeding esp after tonsillectomy, vaginal surg, or dental surgery.
Diagnosed by qual, quant. or both due to variants of vWF. vWF activity measured by platelet function study, bleeding time, and ristocetin induced platelet aggregation RIPA. Factor VIII activity can be low or almost normal. |
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Term
| treatment of vonWillebrands disease |
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Definition
Goal:improve vWF to improve bleeding time. gice cryoprecipitate. txs for hemophilia A lack high molecular wt vWF and do not work as well. Humate P, Koate HS and Koate HP acheive clinical hemostasis prior to surgery and can be used instead of cryoprecipitate.
MILD vW:DDAVP will help vW and factor VIII increasing 4-6fold for 4-8 hrs. Repeat dose Q12. DDAVP should not be used before the type of Vw is known. In type 2BvW disease, DDAVP can cuase platelet aggregation and severe thrombocytopenia. |
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