Hemostatics: Nursing pharmacology

Hemostatics are medications used to induce hemostasis, which is a physiological process that results in clot formation to prevent or stop a hemorrhage.

Primary hemostasis first starts when platelets are activated and aggregate to form a platelet plug at the site of an injured blood vessel.

Next, secondary hemostasis starts with the coagulation cascade, when clotting factors become consecutively activated to ultimately activate prothrombin into thrombin.

The activated thrombin then cleaves fibrinogen into fibrin, which binds with other fibrin proteins to form a fibrin mesh that reinforces the platelet plug.

Now, when the tissue has healed, the endothelial cells produce an enzyme called tissue plasminogen activator, or tPA, which in turn converts plasminogen into its active form plasmin.

Plasmin then acts as a protease by cutting fibrin into smaller pieces, called fibrinolysis, and ultimately dissolving the clot.Now, the most commonly used hemostatics include antifibrinolytics, such as aminocaproic acid and tranexamic acid, and vitamin K analogues like phytonadione, which can be administered orally, intravenously, intramuscularly, or subcutaneously; as well as topical hemostatic agents, such as gelatin, microfibrillar collagen, bovine thrombin, and human fibrin sealant, which are applied topically.

Let’s first focus on antifibrinolytics, which work by inhibiting the conversion of plasminogen to plasmin, which ultimately prevents fibrinolysis.

Now, aminocaproic acid is primarily used as prophylaxis to prevent bleeding after cardiac surgeries, like coronary artery bypass surgery, or CABG, as well as to prevent bleeding in clients with cirrhosis, in which the liver is unable to synthesize clotting factors, and to prevent recurrence of subarachnoid hemorrhage.

Some side effects of aminocaproic acid include malaise and muscle weakness, bradycardia, hypotension, as well as injection site reactions.

Less commonly, aminocaproic acid can cause gastrointestinal side effects like abdominal cramps, nausea, and diarrhea. Finally, prolonged use of aminocaproic acid may lead to myopathy with rhabdomyolysis, which may ultimately result in acute renal failure.

As far as contraindications go, aminocaproic acid is contraindicated in clients who experience disseminated intravascular coagulation, or DIC; this is a state of widespread clot formation in the body associated with platelet consumption and thrombocytopenia, making the client more prone to severe hemorrhage.Caution should also be taken in clients with cardiac, renal and hepatic diseases, as well as during pregnancy, as its effects on the fetus are not well known.Alright, the next antifibrinolytic is tranexamic acid, which can be used to stop or prevent bleeding in clients with hemophilia, as well as in clients with menorrhagia, or heavy menstrual bleeding.

Now, side effects of tranexamic acid include headache, seizures, impaired color vision, as well as abdominal pain, nausea, diarrhea.

On rare occasions, it can result in excessive clotting, which increases the risk of deep vein thrombosis and pulmonary embolism.

For these reasons, tranexamic acid is contraindicated in clients who already have impaired color vision and a history of thromboembolism, as well as active intravascular clotting.

Next, we have vitamin K analogues, such as phytonadione, which is used by the liver as cofactor for the synthesis and activation of certain clotting factors.

Phytonadione is typically administered to clients with vitamin K deficiency, which makes them more susceptible to bleeding.

Specifically, phytonadione is given shortly after birth intramuscularly as prophylaxis to prevent hemorrhagic disease of the newborn.

Vitamin K analogues can cause side effects like dyspnea, chest tightness, and injection site reaction. When given intravenously or intramuscularly, phytonadione has a boxed warning for severe anaphylaxis that can result in shock.

Now, phytonadione is contraindicated in clients with hereditary hypoprothrombinemia, since it may cause a hypercoagulable state.

In addition, it is contraindicated in clients with severe hepatic disease, and during the final weeks of pregnancy. Precautions should be taken during pregnancy and in neonates, as well as when administering intravenously.Alright, now moving on to topical or local hemostatic agents, such as gelatin, microfibrillar collagen, bovine thrombin, and human fibrin sealant.

These are available as a sponge, spray, or solution that can be applied directly to bleeding tissues from injury or surgery, and work by activating the coagulation cascade locally.The main side effects of these agents are an increased risk of wound infection and impaired wound healing.

In addition, bovine thrombin has a boxed warning for severe bleeding and thrombosis, which may result from the development of antibodies.

Finally, clients with allergy to bovine meat or products should not use bovine thrombin, as it may cause anaphylaxis.Now, if your client is experiencing bleeding after receiving fibrinolytic therapy, they can be prescribed a systemic hemostatic agent like aminocaproic acid.

Before administering the hemostatic medication, be sure to assess the location and amount of bleeding, as well as signs of blood loss, such as pallor, cyanosis, and sluggish capillary refill, as well as hypotension, tachycardia, and weak peripheral pulses.

Then, review your client’s laboratory test results, including CBC, CPK, BUN and creatinine, along with coagulation studies.

Also, be sure to confirm there are no client contraindications to receiving the hemostatic agent, such as allergies or religious conflict.

Next, explain to your client how the medication will help stop their bleeding by counteracting the excess fibrinolysis, allowing their body to form a clot effectively.

Lastly, confirm your client has a patent IV site, prepare and administer the medication as ordered.During administration of aminocaproic acid, closely monitor your client’s coagulation studies and observe for signs of thromboembolic complications such as chest pain, dyspnea, or leg pain.

Also monitor for signs of muscle breakdown, such as reddish brown urine and a client report of muscle pain or weakness. After administration, evaluate for the therapeutic effect of controlled bleeding, laboratory values within normal limits, and the absence of side effects.On the flip side, if your client is experiencing uncontrolled bleeding during a surgical procedure, a topical hemostatic such as thrombin can be applied after other hemostatic methods such as pressure, sutures or thermal energy fail to achieve complete hemostasis.

During the procedure, assist the surgeon by ensuring the prescribed hemostatic agent is prepared and delivered to the surgeon for use while maintaining the sterile environment.

Then, assist with suctioning or sponging the bleeding area before applying the medication. Postoperatively, continue to monitor your client for signs of hemorrhage as well as thrombosis.

Alright, as a quick recap, hemostatic agents are prescribed to clients to induce hemostasis and prevent hemorrhage. They act on specific components of the clotting cascade, and can be administered systemically or topically.

When caring for a client receiving a hemostatic agent, nursing considerations center around client assessment, including baseline laboratory values and physical assessment findings that indicate hemorrhage or side effects like thrombosis.

hemorrhage, as well as thrombosis All right, as a quick recap hemostatic agents are prescribed to clients to induce hemostasis and prevent Hemorrhage.

They act on specific components of the clotting Cascade, and can be administered systemically or topically, when caring for a client receiving, a hemostatic agent.

Nursing consideration center around client assessment including Baseline laboratory values and physical assessment findings