Anticoagulants

• One type of blood clotting disorders is increased blood clotting: thrombophilia
• With an increased blood clotting tendency


  Blood clots can form within the blood vessel without any damage to the vessel
• These blood clots can then drift further and block the narrowed blood vessels
• When blood vessels are blocked

  The supply of nutrients and oxygen to the surrounding tissue ceases and the tissue dies
• Consequences of thrombosis


  • Deep vein thrombosis
  • Pulmonary embolism
  • Stroke
  • Heart attack
• Thrombocytes


  Also known as platelets, play an important role in blood clotting
• Thrombocytes are the shaped elements of blood
• Thrombocytes are formed in

  The bone marrow
• Main task of thrombocytes


  To close the injury by colliding with each other, thus stopping the bleeding
• A different amount of thrombocytes than normal can indicate blood clotting problems
• Conditions indicated by abnormal thrombocyte levels

  • Blood clotting problems
  • Bone marrow diseases
  • Certain tumors
  • Folic acid/vitamin B12 deficiency
• INR regular monitoring is important for those who take older types of anticoagulants (coumarin derivatives)
• INR


  A parameter used to test blood coagulation and check the effectiveness of anticoagulant therapy
• A value that is too high


  Can cause bleeding
• A value that is too low


  Increases the chance of blood clots
• In patients with a moderate risk of thrombus formation, the therapeutic INR value is set between 2 and 3
• Conditions with moderate risk of thrombus formation


  • Deep vein thrombosis
  • Atrial fibrillation
  • Dilated cardiomyopathy
  • Cerebrovascular event
  • Carotid and peripheral vascular diseases
• For those with a high risk of thrombus formation, the therapeutic value is set between 2.5 and 3.5
• Conditions with high risk of thrombus formation

  • Artificial valve
  • Hypercoagulable conditions
• An INR above 4 is not necessary even with an artificial valve
• Prothrombin time (PI)


  The time in seconds between the addition of tissue thromboplastin to the blood plasma to be tested and the formation of a clot
• The method for measuring prothrombin time was developed by Quick et al. in 1935
• 1. dimer


  Formed during the dissolution of the formed blood clot, plays a significant role in the diagnosis of venous thrombosis
• The value of D-dimer can be influenced by many factors
• Factors influencing D-dimer value

  • Autoimmune diseases
  • Underlying tumor diseases
  • Inflammatory processes
• High levels of homocysteine can increase the chance of both arterial and venous thrombosis
• Homocysteine


  An amino acid that can cause great damage to the vessel wall
• Folic acid and vitamin B12 are needed for the breakdown of homocysteine
• APTI


  The Activated Partial Thromboplastin Time shows the time until clotting
• Prolongation of APTI results in bleeding
• Hemostasis


  Ensures that blood circulates within the vasculature
• If the balance of the processes is disturbed

  Blood clotting and bleeding develops
• Medicines that affect blood clotting

  • Anticoagulants
  • Platelet inhibitors
  • Fibrinolytics
• Stages of blood coagulation

  • Vasoconstriction
  • Platelet phase
  • Coagulation cascade
  • Fibrinolysis
• Heparin


  A standard anticoagulant produced in mast cells, effective both in vivo and in vitro
• Heparin amplifies antithrombin III's effect (3500x), which inactivates thrombin and activated factors
• Heparin cannot be given to pregnant women
• Indications for heparin


  • Deep vein thrombosis
  • Acute coronary syndrome
  • Pulmonary embolism
• Side effects of heparin

  • Blood sensitivity
  • Decrease in platelet count
  • HIT
  • Osteoporosis
• In case of bleeding, the effect of heparin can be suspended by giving protamine sulfate