Clinical Aspects of and Therapy for Hemophilia A. Incidence. Clinical Severity, страница 8

The common side effects of DDAVP include facial warmth and flushing during the infusion. Insignificant variations in blood pressure may be noted. Headaches may occur as late as 6–8 hours after the infusion. Abdominal cramping with diarrhea and generalized myalgias have rarely been noted. In very ill patients, fluid retention resulting in congestive heart failure has been reported. MLID85223521  44 In small children receiving large fluid volumes, seizures induced by severe hyponatremia after DDAVP infusion have recently occurred. MLID90053541  45 In the young pediatric age group serum sodium levels should be monitored and large amounts of intravenous fluid avoided if DDAVP is used, especially if repeated doses are given. Myocardial infarction temporally related to DDAVP infusion has been reported, MLID88094560  46 although whether DDAVP truly causes a hypercoagulable state is unclear. These serious side effects are very uncommon. In summary, DDAVP is the treatment of choice in persons with mild hemophilia A if they respond adequately.

Surgery And Hemophilia

Both elective and emergency surgery can be done in  a patient with hemophilia A unless an inhibitor is present.  Before surgery (1) a hematologist and diagnostic  coagulation laboratory should be available; (2) the surgeon  should feel comfortable handling a patient with a  coagulation disorder; (3) there should be a blood bank or  pharmacy capable of providing adequate amounts of the  appropriate replacement material; (4) an appropriate  rehabilitation team should be available for postoperative  management, especially with orthopaedic surgery; and  (5) no inhibitor should be present. An inhibitor level  must be checked immediately prior to surgery. Surgery  should be scheduled on Monday or Tuesday to allow for  availability of laboratory services for factor level assays  and best access to consultants.

Preoperative orders should include “No IM  medication” and “No ASA-containing compounds such as  Darvon, Empirin or percodan.” For major surgery, the factor  VIII level should be brought to the 80 - 100% range (40–50  U/kg) about 1 hour prior to surgery and then kept  >30–50% for 10–14 days. The theoretical calculations  should be checked every 2–3 days with factor VIII assays  and the dose adjusted accordingly.

Postoperatively, pain management should be  aggressive, with patient-assisted narcotic delivery systems  (PCA) or constant infusional narcotic dosing.

For oral surgery such as impacted wisdom teeth  removal, the factor level prior to surgery is raised to 100%  with infusions. Postoperatively e-aminocaproic acid (1 g  PO every 4 hours) for 7–10 days is given. If the dental  procedure is minor, e-aminocaproic acid may be used  alone.

Patients with mild hemophilia may be able to utilize  DDAVP. If there is a poor response to DDAVP, some  physicians use cryoprecipitate. However, if DDABP cannot be  used, we recommend factor concentrate since it can be  treated with viricidal methods and is thus currently safer  than cryoprecipitate.

Complications of factor use include hepatitis C, which  has largely been eliminated by the new production  methods and hemolysis due to anti-A or anti-B in the  concentrate preparation. If hemolysis occurs, blood loss should  be replaced by type O packed red cells, and concentrates  with low isoagglutinin titers should be obtained and  utilized.

Health Care Delivery

The keystone of therapy in hemophilia is to provide the patient with access to immediate and adequate correction of the hemostatic defect at the earliest symptom suggestive of hemorrhage. For most persons with severe and moderately severe hemophilia, the achievement of this goal is through a combination of intensive education of the patient and family, plus the institution of a carefully supervised self-therapy program.

Self-Therapy Program