Vitamin K Treatment for Bleeding

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Questions and Answers

Which of the following conditions is most likely treated with thrombopoietin receptor agonists like Romiplostim?

Bladder hemorrhage secondary to radiation

Hyperplasminaemic bleeding state

Chronic Idiopathic thrombocytopenic purpura (ITP) (correct)

Acute attacks of Idiopathic thrombocytopenic purpura (ITP)

What is a significant contraindication for the use of treatments aimed at managing clotting issues?

Total thrombocytopenia

Prior allergic reactions to medications

Recent surgery

Genitourinary bleeding of the upper tract (correct)

Which of the following is NOT an adverse effect associated with Protamine sulfate?

Bradycardia

Flushing

Abdominal discomfort (correct)

Hypersensitivity

How do corticosteroids assist in the treatment of Idiopathic thrombocytopenic purpura (ITP)?

Through immune suppression Signup and view all the answers

What is the primary action of Rho (D) immune globulin in ITP treatment?

The mechanism of action is not fully understood Signup and view all the answers

Which of the following is typically used as a second-line treatment for ITP?

Dapsone Signup and view all the answers

What type of bleeding scenarios are managed with the use of vitamin K related treatments?

Trauma and postpartum hemorrhage Signup and view all the answers

Which vitamin form is synthesized by intestinal bacteria?

Vitamin K2 (menaquinone) Signup and view all the answers

What adverse effect is common with the rapid injection of Protamine sulfate?

Dyspnea Signup and view all the answers

What is the onset of action for intravenous administration of phytomenadione (Vitamin K1)?

12 hours Signup and view all the answers

Why should intravenous vitamin K1 be administered slowly?

To avoid potential adverse reactions like dyspnea Signup and view all the answers

Which condition is NOT an indication for vitamin K treatment?

Hemolytic anemia in neonates Signup and view all the answers

What is the primary mechanism of action of aminocaproic acid and tranexamic acid?

Inhibit plasmin activation Signup and view all the answers

What is a potential side effect of both aminocaproic acid and tranexamic acid?

Intravascular thrombosis Signup and view all the answers

Which vitamin requires bile salts for absorption?

Vitamin K1 (phylloquinone) Signup and view all the answers

Which vitamin is preferred for patients with malabsorption syndrome?

Menadiol sodium phosphate (K3) Signup and view all the answers

Study Notes

Vitamin K Treatment of Bleeding

Vitamin K is a fat-soluble vitamin.
Two forms exist: Vitamin K1 (phylloquinone) and Vitamin K2 (menaquinone).
Vitamin K1 is found in food, while Vitamin K2 is found in human tissues and synthesized by intestinal bacteria.
Both Vitamin K1 and K2 require bile salts for absorption from the intestines.
Vitamin K is available in oral and parenteral (injectable) forms.
Onset of effect is delayed for 6 hours, but complete effect is seen within 24 hours.
Used to treat reduced prothrombin activity caused by excess warfarin or Vitamin K deficiency.
Intravenous administration must be slow to prevent dyspnea, chest/back pain, and even death.

Mechanism of Action

Vitamin K is crucial for the final stage of synthesis of 6 clotting factors in the liver.
This involves γ-carboxylation of glutamic acid residues in factors 2, 7, 9, and 10, and anticoagulant proteins S and C.

Vitamin K Preparations

Phytomenadione (Vitamin K1): Acts within 12 hours, and intravenous formulations are used in emergencies.

Menaquinone (Vitamin K2)

Menaquinone-7 is a form of Vitamin K2.
It is water-soluble and doesn't require bile salts for absorption, making it preferred in malabsorption syndromes.
However, it takes 24 hours to act, so it isn't used for treating warfarin overdose.
It may cause hemolytic anemia, so it is avoided in neonates, especially those with G6PD deficiency.

Menadiol Sodium Phosphate (Vitamin K3)

Water-soluble, and doesn't need bile salts for absorption.
Preferred in conditions with malabsorption.
Takes 24 hours to act, not used to treat warfarin overdose.
Can cause hemolytic anemia, so it's not recommended for neonates, especially those with G6PD deficiency.

Indications for Vitamin K Therapy

Hemorrhage due to coumarin anticoagulants
Hemorrhagic disease of the newborn
Hypoprothrombinemia (due to malabsorption)
Vitamin K deficiency (frequently seen in hospitalized patients with poor diet, parenteral nutrition, recent surgery, multiple antibiotic therapy, and uremia).
Blood transfusion may be used for severe hemorrhage.

Aminocaproic Acid and Tranexamic Acid

Both are synthetic, orally active, and excreted in the urine
Inhibit plasminogen activation.
Tranexamic acid is 10 times more potent than aminocaproic acid.
Potential side effect: intravascular thrombosis

Bleeding Due to Idiopathic Thrombocytopenic Purpura (ITP)

Corticosteroids are a first-line treatment.
Rho (D) immune globulin (Human; Anti-D): mechanism of action isn't fully understood.
Immunosuppressants (like Azathioprine)
Mycophenolate mofetil
Intravenous immunoglobulin (IVIg)
Thrombopoietin receptor agonists (Romiplostim and Eltrombopag): stimulate platelet production in the bone marrow.

Dapsone

Anti-infective sulfone drug used as a second-line treatment for ITP.

Rituximab

Chimeric monoclonal antibody against the B-cell surface antigen CD20.
Alternative treatment to splenectomy.

Protamine Sulfate

Antagonizes the anticoagulant effects of heparin.
Potentially causes hypersensitivity, dyspnea, flushing, bradycardia, and hypotension when injected rapidly. -Contraindicated in patients with DIC or genitourinary bleeding of the upper tract.

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Description

Explore the role of Vitamin K in treating bleeding conditions. Learn about its forms, mechanism of action, and preparations used in clinical settings. This quiz covers essential information on the administration and effects of Vitamin K.