Rosen & Barkin's 5-Minute Emergency Medicine Consult (779 page)

Direct pressure for control of hemorrhage

Resuscitation with crystalloid and packed RBCs as needed

• As with all significant bleeding, apply direct pressure to site of bleeding
  
• 3 treatment strategies:
  
  • Increase endogenous vWF
    
  • Replacement of vWF
    
  • Agents that generally promote hemostasis but do not alter levels of vWF
    
• Desmopressin acetate (DDAVP):
  
  • Promotes release of vWF from endothelial cells, increases factor VIII levels
    
  • Maximal levels obtained at 30–60 min, with duration of 6–8 hr
    
  • Effective for type 1; variable effectiveness for type 2; not indicated for type 3
    
  • Patients may use intranasal spray at home before menses or minor procedures
    
• vWF replacement therapy:
  
  • Humate-P factor VIII concentrate with vWF:
    
    • Treated to reduce virus transmission risks
      
    • Indicated for type 3 vWD and severe bleeding in all types
      
    • Doses, length of treatment depend on severity of bleeding
      
    • Cryoprecipitate is no longer a treatment of choice as it carries risk of virus transmission. If no other treatments are available and patient having life-threatening hemorrhage, it can be used
      
• Antifibrinolytic therapy:
  
  • Aminocaproic acid (Amicar) and tranexamic acid (Cyklokapron)
    
  • Block plasmin formation to prevent clot degradation
    
• Topical agents—applied directly to bleeding site:
  
  • Gelfoam or Surgicel soaked in thrombin
    
  • Micronized collagen
    
  • Fibrin sealant
    
• Avoid antiplatelet agents
  

• Minor bleeding (epistaxis, oropharyngeal, soft tissue):
  
  • IV or intranasal desmopressin
    
• Major bleeding (intracranial, retroperitoneal):
  
  • Replace vWF and factor VIII so activity level is at least 100 IU/dL
    

• Minor bleeding:
  
  • vWF concentrate:
    
    • Given if desmopressin is ineffective
      
    • Should be given in consultation with a hematologist
      
  • Aminocaproic acid or tranexamic acid:
    
    • For mild mucocutaneous bleeding
      

• Aminocaproic acid: 50–60 mg/kg PO/IV q4–q6h
  
• Cryoprecipitate: 10–12 U initial dose or 2–4 bags/10 kg
  
• Desmopressin (DDAVP):
  
  • 0.3 μg/kg IV, max. 20 μg
    
  • 0.3 μg/kg SQ, max. 20 μg
    
  • 300 μg (1 spray each nostril) intranasal
    
  • Peds: <50 kg—150 μg (1 spray in each nostril) intranasal
    
• Antihemophilic factor/vWF complex, human (Humate-P): 20–40 U/kg IV
  
• Tranexamic acid: 20–25 mg/kg PO, IV q8h
  
• Fresh frozen plasma (FFP)—10–20 mL/kg IV
  

FOLLOW-UP

• Patients with significant bleeding requiring further IV medical management
  
• Observation after major trauma for types 2 and 3 vWD
  
• Consider transferring patients with major bleeding events to a center with round-the-clock lab capability, and a care team that includes a hematologist and a surgeon skilled in management of bleeding disorders
  

• Control of hemorrhage
  
• Adequate follow-up and access to medical therapy
  

Hematology:

• Severe, difficult-to-manage bleeding
  
• Prior to elective/semielective procedures
  
• Definitive workup of suspected cases
  

Patients may not know their type of hemophilia:

• Consider FFP for the patient with unknown type of hemophilia in the setting of trauma or bleeding
  

• Mannucci P. Treatment of von Willebrand disease.
  N Engl J Med
  . 2004;351:683–694.
  
• Nichols WL, Hultin MB, James AH, et al. von Willebrand disease (vWD): Evidence-based diagnosis and management guidelines, the National Heart, Lung and Blood Institute (NHLBI) Expert Panel report (USA).
  Haemophilia
  . 2008;14:171–232.
  
• Pacheco L, Costantine M, Saade G, et al. von Willebrand disease and pregnancy: A practical approach for the diagnosis and treatment.
  Am J Obstet Gynecol.
  2010;203(3):194–200.
  
• Robertson J, Lillicrap D, James P. Von Willebrand disease.
  Pediatr Clin North Am.
  2008;55(2):377–392.
  
• The Diagnosis, Evaluation and Management of von Willebrand Disease. National Heart, Lung and Blood Institute.
  Available at
  http://www.nhlbi.nih.gov/guidelines/vwd./
  Accessed January 14, 2013.
  

See Also (Topic, Algorithm, Electronic Media Element)

Hemophilia

CODES

286.4 Von Willebrand's disease

BASICS

• Most commonly prescribed oral anticoagulant
  
• Inhibits vitamin K metabolism required for activation of factors II, VII, IX, and X
  
• Blocks the coagulation cascade’s extrinsic system and common pathway
  
• Commonly used for venous thromboembolism and prevention of embolism with prosthetic heart valves or atrial fibrillation
  
• Adjustments based on the international normalization ratio (INR)
  
  • Typical therapeutic range 2–3
    
  • 2.5–3.5 for mechanical valves and antiphospholipid syndromes
    
• Contraindications include any condition in which the risk of hemorrhage or adverse reaction outweighs clinical benefit
  
  • Prior hypersensitivity
    
  • Skin reactions
    
  • Recent surgeries
    
  • Active or potential GI, intracerebral, or genitourinary bleeding
    
  • Fall risk
    

• Bleeding complications:
  
  • 15% of patients/yr
    
    • 4.9% major bleeding events
      
    • Up to 0.8% fatal, most commonly intracranial hemorrhage (ICH)
      
  • Bleeding risk is directly related to INR
    
    • Increases dramatically above 4
      
• Risk factors for nontherapeutic INR:
  
  • Age >75 yr
    
  • Hypertension, cerebrovascular disease, severe heart disease
    
  • Diabetes, renal insufficiency
    
  • Alcoholism or liver disease
    
  • Hypermetabolic states, fever
    
  • Hyperthyroidism
    
  • Cancer
    
  • Collagen vascular disease
    
  • Hereditary warfarin resistance
    
  • Cytochrome P450 polymorphism
    

• Pregnancy class X
  
• Crosses the placenta causing spontaneous abortion and birth defects
  

DIAGNOSIS

• Presentation may be occult or dramatic:
  
  • High index of suspicion required to detect potentially life-threatening complications
    
• Subtherapeutic/low INR: Breakthrough thrombosis
  
• Therapeutic and supratherapeutic: GI, CNS, retroperitoneal bleeding
  
• Skin necrosis and limb gangrene:
  
  • Classic lesions of warfarin skin necrosis and limb gangrene begin on the 3rd–8th day of therapy
    
  • Capillary thrombosis in subcutaneous fat (skin necrosis) and obstruction of venous circulation of the limb (limb gangrene)
    
  • Often associated with protein C deficiency
    
  • Eschar in center differentiates lesions from ecchymosis
    
• Intentional overdose
  
  • May be asymptomatic
    
  • Superwarfarin (rat poison) can result in prolonged bleeding risk (months)
    
  • Follow serial INR
    
  • Do not start vitamin K empirically, may mask late development of INR elevation
    
  • Consider activated charcoal