CHP. 22 Disorders of Hemostasis
Vitamin __________ is most closely associated with the physiology of hemostasis.
K
Platelet plug formation involves adhesion and __________ of platelets.
aggregation
__________ is the term used to describe the state of exaggerated hemostasis that predisposes individuals to thrombosis and blood vessel occlusion.
Hypercoagulability
The __________ is the organ most closely associated with platelet storage and destruction.
spleen
A 55-year-old man has begun taking one 81-mg aspirin tablet daily on the recommendation of his physician. The physician had told him that this would help to prevent heart attack and stroke. A. What is the desired action of aspirin in terms of heart attack and stroke prevention?
A. The desired action of aspirin in heart attack and stroke prevention is its ability to reduce platelet aggregation and thereby prevent the formation of blood clots that could block arteries and cause these cardiovascular events.
Which medication is an example of an antiplatelet? Atropine Clopidogrel Warfarin Alteplase
Clopidogrel Clopidogrel is an example of an antiplatelet, as is aspirin. Atropine is for symptomatic bradycardia, warfarin is an anticoagulant, and alteplase is a thrombolytic.
The intrinsic and extrinsic clotting pathways result in two different types of clots. T/F
False
Which intervention should be implemented for patients on any medications that increase the risk of bleeding? Utilize basic razors. Encourage intramuscular (IM) injections. Monitor for dark stools. Disregard fall precautions.
Monitor for dark stools. For patients on medications that increase the risk for bleeding, the patient should be alert for signs of bleeding, which may include bleeding gums, bruising, dark stools. Other interventions include maintaining fall precautions, avoiding IM injections, and using electric razors.
How should intravenous (IV) heparin be administered? By gravity, counting drips By an advanced practice RN On a pump with guardrails On a pressure bag
On a pump with guardrails Heparin is a high-alert drug that should be administered on a pump with guardrails. It should never be hung to gravity, does not need to be administered by an advanced practice nurse, and should never be administered on a pressure bag.
Which factor is an absolute contraindication to receiving a thrombolytic? Ischemic stroke Pregnancy Appendectomy 2 years ago Controlled hypertension
Pregnancy Contraindications for thrombolytics include pregnancy, recent gastrointestinal bleed, hemorrhagic stroke, a known bleeding disorder, recent major surgery or trauma, history of intracranial vessel malformation, and uncontrolled hypertension. Ischemic stroke, appendectomy in the past, and controlled hypertension are not contraindications for thrombolytic administration.
A patient is on a heparin infusion. How does the nurse know if the medication is infusing at a therapeutic rate? The international normalized ratio (INR) is between 2 and 3. The prothrombin time (PT) is 1.5 to 2 times the normal time. The activated partial thromboplastin clotting time (aPTT) is 1.5 to 2.5 times the normal time. The potassium level is between 3.5 and 5.
The activated partial thromboplastin clotting time (aPTT) is 1.5 to 2.5 times the normal time. Heparin is trended using the aPTT. INR and PT trends warfarin. Potassium is not trended for anticoagulant use.
How do anticoagulants work? Thin the blood to prevent clots and stop clots from getting bigger. Prevent platelets from sticking to stents. Dissolve clots. Decrease bleeding times.
Thin the blood to prevent clots and stop clots from getting bigger. Anticoagulants work by thinning the blood to prevent clots and to stop them from getting bigger. Antiplatelets prevent platelets from sticking to stents, and thrombolytics dissolve clots.
Clots must be dissolved in a timely fashion to ensure appropriate hemostasis. T/F
True
Persons with hemophilia often require transfusions of clotting factors. T/F
True
The liver is responsible for the production of the majority of clotting factors. T/F
True
The drug most closely associated with inhibition of platelet aggregation is __________.
aspirin
What type of medication is heparin? Antiplatelet Anticoagulant Thrombolytic Antihypertensive
Anticoagulant Heparin is an anticoagulant. It "thins" the blood to prevent new blood clots from forming and keeps current clots from getting bigger.
A patient is ordered subcutaneous heparin every 8 hours. When the patient asks what this medication is for, what is the nurse's best answer? "It is to prevent you from developing a blood clot." "It will keep your current clots from getting bigger." "Everyone is on this medication." "It allows us to trend your aPTT levels."
"It is to prevent you from developing a blood clot." Subcutaneous heparin every 8 hours is given to prevent clots. Intravenous (IV) heparin is administered to prevent clots and to keep current clots from getting bigger. It is not accurate that everyone is on heparin and saying so does not address the question. Activated partial thromboplastin clotting time (aPTT) is monitored with IV infusion only and not a reason for administering heparin.
The new mother is admitted to the intensive care unit and started on low-molecular-weight heparin and warfarin. She is told that she will be discharged in a day or 2 and will remain on the heparin for 5 days and the warfarin for at least 3 months. A. Anticoagulation with heparin and warfarin is not a definitive treatment for clot removal in pulmonary embolism but a form of secondary prevention. Explain.
A. Anticoagulation with heparin and warfarin does not remove the existing clot but prevents it from growing and stops new clots from forming, allowing the body's natural clot-dissolving mechanisms to work effectively. This approach reduces the risk of further complications and recurrent pulmonary embolism, which is why it is considered secondary prevention.
A 29-year-old new mother, who delivered her infant 3 days ago, is admitted to the hospital with chest pain and is diagnosed as having venous thrombosis with pulmonary emboli. A. What factors would contribute to this woman's risk of developing thromboemboli?
A. The risk of thromboemboli in this postpartum woman is due to a combination of physiological changes associated with pregnancy and delivery, potential immobility, and other individual risk factors. (hypercoagulable state of pregnancy and the postpartum period, venous stasis, endothelial injury from delivery, hormonal changes, physical stress and immobility, potential cesarean section, personal or family history of thrombosis, obesity, and other medical conditions like thrombophilias, preeclampsia, and gestational diabetes)
A patient is on a heparin infusion. Which lab value is used to titrate this medication? International normalized ratio (INR) Prothrombin time (PT) Activated partial thromboplastin clotting time (aPTT) Hemoglobin
Activated partial thromboplastin clotting time (aPTT) aPTT is used to guide titration in patients receiving heparin. PT and INR are monitored in patients receiving warfarin. Hemoglobin is monitored with all anticoagulants but does not impact titration.
What is the antidote for heparin? Vitamin K Protease inhibitors Vitamin D Protamine sulfate
Protamine sulfate Protamine sulfate is the antidote for heparin. Vitamin K is the antidote for warfarin. Protease inhibitors and vitamin D are unrelated to the action of heparin.
Thrombocytopenia predisposes an individual to inappropriate bleeding. T/F
True