Two inherited bleeding disorders—hemophilia A and hemo-philia B—are clinically indistinguishable, although they can be distinguished by laboratory tests. Hemophilia A is caused by a genetic defect that results in deficient or defective factor VIII; he-mophilia B (also called Christmas disease) stems from a genetic de-fect that causes deficient or defective factor IX.
Hemophilia is a relatively rare disease; hemophilia A, which occurs in 1 of every 10,000 births, is three times more common than hemophilia B. Both types of hemophilia are inherited as X-linked traits, so al-most all affected people are males; females can be carriers but are almost always asymptomatic. The disease is recognized in early childhood, usually in the toddler age group. However, patients with mild hemophilia may not be diagnosed until they experience severe trauma (eg, a high-school football injury) or surgery. He-mophilia occurs in all ethnic groups.
The disease, which can be severe, is manifested by hemorrhages into various parts of the body. Hemorrhage can occur even after minimal trauma. The frequency and severity of the bleeding de-pend on the degree of factor deficiency as well as the intensity of secondary to trauma. In contrast, spontaneous hemorrhages, par-ticularly hemarthroses and hematomas, can frequently occur in patients with severe factor VIII deficiency (ie, less than 1% of nor-mal levels). These patients require frequent factor replacement therapy.
About 75% of all bleeding in patients with hemophilia occurs into joints. The most commonly affected joints are the knees, elbows, ankles, shoulders, wrists, and hips. Patients often note pain in a joint before they are aware of swelling and limitation of mo-tion. Recurrent joint hemorrhages can result in damage so severe that chronic pain or ankylosis (fixation) of the joint occurs. Many patients with severe factor deficiency are crippled by the joint dam-age before they become adults. Hematomas can be superficial or deep hemorrhages into muscle or subcutaneous tissue. With severe factor deficiency, they can occur without known trauma and pro-gressively extend in all directions. When the hematomas occur within muscle, particularly in the extremities, peripheral nerves can be compressed. Over time, this compression results in decreased sensation, weakness, and atrophy of the area involved. Spontaneous hematuria and gastrointestinal bleeding can occur. Bleeding is also common in other mucous membranes, such as the nasal passages. The most dangerous site of hemorrhage is in the head (intracranial or extracranial). Any head trauma requires prompt evaluation and treatment. Surgical procedures typically result in excessive bleeding at the surgical site. Because clot formation is poor, wound healing is also poor. Such bleeding is most commonly associated with den-tal extraction.
In the past, the only treatment for hemophilia was infusion of fresh frozen plasma, which had to be administered in such large quantities that patients experienced fluid volume overload. Now factor VIII and factor IX concentrates are available to all blood banks. Recombinant forms of these factors have been made avail-able and may diminish the use of factor concentrates. Patients are given concentrates when they are actively bleeding or as a pre-ventive measure before traumatic procedures (eg, lumbar punc-ture, dental extraction, surgery). The patient and family are taught how to administer the concentrate intravenously at home at the first sign of bleeding. It is crucial to initiate treatment as soon as possible so that bleeding complications can be avoided. A few patients eventually develop antibodies to the concentrates, so their factor levels cannot be increased. Treatment of this problem is extremely difficult and often unsuccessful.
Aminocaproic acid (EACA; Amicar) is a fibrinolytic enzyme inhibitor that can slow the dissolution of blood clots that do form; it is very effective as an adjunctive measure after oral surgery. It is also useful in treating mucosal bleeding. Another agent, desmo-pressin (eg, DDAVP), induces a transient rise in factor VIII lev-els; the mechanism for this response is unknown. In patients with mild forms of hemophilia A, desmopressin is extremely useful, significantly reducing the amount of blood products required. However, desmopressin is not effective in patients with severe fac-tor VIII deficiency. the precipitating trauma. For example, patients who have a mild factor VIII deficiency (ie, 6% to 50% of normal levels) rarely develop hemorrhage spontaneously; hemorrhage tends to occur
Most patients with hemophilia are diagnosed as children. They often require assistance in coping with the condition because it is chronic, places restrictions on their lives, and is an inherited dis-order that can be passed to future generations. From childhood, patients are helped to accept themselves and the disease and to iden-tify the positive aspects of their lives. They are encouraged to be self-sufficient and to maintain independence by preventing un-necessary trauma that can cause acute bleeding episodes and tem-porarily interfere with normal activities. As they work through their feelings about the condition and progress to accepting it, they can assume more and more responsibility for maintaining optimal health.
Patients with mild factor deficiency may not be diagnosed until adulthood if they do not experience significant trauma or surgery as children. These patients need extensive teaching about activity restrictions and self-care measures to diminish the chance of hemorrhage and complications of bleeding. The nurse should emphasize safety at home and in the workplace.
Patients with hemophilia are instructed to avoid any agents that interfere with platelet aggregation, such as aspirin, NSAIDs, herbs, nutritional supplements, and alcohol. This restriction ap-plies to over-the-counter medications such as cold remedies. Dental hygiene is very important as a preventive measure because dental extractions are so hazardous. Applying pressure may be sufficient to control bleeding resulting from minor trauma if the factor deficiency is not severe. Nasal packing should be avoided, because bleeding frequently resumes when the packing is re-moved. Splints and other orthopedic devices may be useful in pa-tients with joint or muscle hemorrhages. All injections should be avoided; invasive procedures (eg, endoscopy, lumbar puncture) should be minimized or performed after administration of ap-propriate factor replacement. Patients with hemophilia should be encouraged to carry or wear medical identification.
During hemorrhagic episodes, the extent of bleeding must be assessed carefully. Patients who are at risk for significant com-promise (eg, bleeding into the respiratory tract or brain) warrant close observation and systematic assessment for emergent com-plications (eg, respiratory distress, altered level of consciousness). If the patient has had recent surgery, the nurse frequently and carefully assesses the surgical site for bleeding. Frequent vital sign monitoring is needed until the nurse is certain that there is no ex-cessive postoperative bleeding.
Analgesics are commonly required to alleviate the pain associated with hematomas and hemorrhage into joints. Many patients report that warm baths promote relaxation, improve mobility, and lessen pain. However, during bleeding episodes, heat, which can accen-tuate bleeding, is avoided; applications of cold are used instead.
Although recent technology (ie, the formulation of heat-solvent or detergent-treated factor concentrates) has rendered fac-tor VIII and IX preparations free from viruses such as HIV and hepatitis, many patients have already been exposed to these infec-tions. These patients and their families may need assistance in cop-ing with the diagnosis and the consequences of these infections.
Between 15% and 50% of patients with hemophilia A and be-tween 1% and 3% of patients with hemophilia B develop anti-bodies (inhibitors) to factor concentrates, complicating factor replacement management (Lusher, 2000; White, Greenwood, Escobar, & Frelinger, 2000). These patients may require plasma-pheresis or concurrent immunosuppressive therapy, particularly in the setting of significant bleeding. Patients with severe factor deficiency should be screened for antibodies, particularly before major surgery.
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