Exam 2 Flashcards
What protein prevents clot formation?
Anti-thrombin III
What is heparin used for?
Prophylaxis and treatment of thromboembolic events
Prevents formation of new clots and prevents enlargement of existing clots
What route and frequency is heparin usually given for PROPHYLACTIC anticoagulation?
subcutaneous, q8-12hrs
What route is heparin given for THERAPEUTIC anticoagulation?
Intermittent or continuous IV infusion
What is the dosing of heparin based on when used for therapeutic anticoagulation?
weight-based dosing, and a bolus (loading dose) is given first
What lab needs to be monitored when giving heparin for therapeutic anticoagulation?
aPTT
What does Activated Partial Thromboplastin Time (aPTT) measure?
Time, in seconds, it takes for a clot to form
What is the normal range for aPTT?
30-40 seconds
What is the therapeutic range for aPTT? What value would be concering?
Therapeutic range 1.5-2.5x the control
Concerning if greater than 70 seconds
How often is aPTT drawn for an INTERMITTENT infusion?
aPTT drawn 30 min before each dose initial therapy and then periodically
How often is aPTT monitored for continuous infusions? What do you do if aPTT is above theraputic?
q4-6 hrs
If above therapeutic stop heparin for 1 hr and redraw aPTT
What type of heparin is Heparin-Induced Thrombocytopenia (HIT-Type I) common with?
Unfractionated heparin (UFH) rather than enoxaparin (low-molecular-weight heparin, LMWH)
What is the onset time for HIT-Type 1?
Within 2 days of starting Heparin
What happens to the platelet count in HIT-Type 1?
Drops slightly but normalizes on its own
What is the management for HIT-Type 1?
Heparin therapy can continue, as this form is not dangerous.
What is the cause of HIT-Type 2?
It is an immune reaction where heparin binds to platelet factor, triggering antibody formation
What is the onset time for HIT-Type 2?
Develops 5-14 days after starting heparin
What are the effects of HIT-Type 2?
Hypercoagulable state - increased risk of blood clots despite low platelet count.
Increased platelet activation - antibody coated platelets become overactive, leading to clot formation.
Macrophages remove platelets.
Thrombotic complications.
What is the management of HIT-Type 2?
Stop heparin immediately.
Use a non-heparin anticoagulant.
What is enoxaparin (Lovenox) used for?
VTE prophylaxis or Tx of DVT/PE
“Bridge therapy”
What is the MOA of enoxaparin?
inhibits factor 10a
What should you assess for when giving enoxaparin?
Thrombocytopenia and bleeding
What is the dose and frequency of enoxaparin when given prophylacticly?
30-40mg daily or q12 h
What is the dose for enoxaparin when given for the Tx of DVT or PE?
1mg/kg q12h or 1.5mg/kg q24hr (weight based)
What are the nursing implications for Heparin and enoxaparin (Lovenox)?
Never use heparin and enoxaparin concurrently.
Assess for signs of bleeding, and stop medication if found.
Contraindicated w hemorrhagic stroke and uncontrolled HTN.
Monitor platelet count for thrombocytopenia (more critical with heparin).
D-D interactions: NSAIDS, antiplatetes
Herbal products such as, ginger, ginko, green tea, ginseng, increase risk of bleeding
What is the antidote for Heparin?
protamine sulfate IV
What is the primary function of neutrohils?
Neutrophils respond to bacterial infections and have phagocytic fuction
How long do neutrophils live?
1-2 days
What do neutrophil granules contain?
Granules contain antimicrobial proteins that help kill bacteria
When are band cells (immature neutrophils) produced and what is their function?
The body stimulates band cells (immature neutrophils) during a severe inflammatory response. Band cells are capable of phagocytosis.
What does an increased number of band cells indicate?
An increase in band cells is called a “left shift,” which suggests an active infection or inflammation.
What is the normal range for band cells?
Band cells normally range from 0-5%
What is the primary function of lymphocytes?
Lymphocytes provide immunity against pathogens and help destroy invading viruses and some bacteria.
What are the functions of monocytes?
Migrate into tissues and transform into macrophages
Phagocytic cells
Ingest bacteria, debris, and old/defective RBCs
What is the role of C-reactive protein (CRP)?
CRP is a non-specific inflammatory marker that is present in tissue injury & acute inflammation.
When does CRP appear after an inflammatory response? When does CRP peak?
CRP appears 6-10 hours after inflammation begins.
CRP peaks 48-72 hours after the start of inflammation.
What conditions can elevate CRP levels?
CRP may be elevated with hypertension (HTN), smoking, and cardiovascular disease (CVD).
What is the normal CRP level?
Less than 3 mg/dL.
What are non-modifiable risk factors for CAD?
Age and gender - greater than 45 years for males and greater than 55 years for females
Ethnicity - African Americans, Native Americans
Genetic predisposition and family hx
What are the modifiable risk factors for CAD?
Abnormal cholesterol & lipid levels
HTN
DM
Tobacco use
Physical inactivity
Obesity
What contributes to high triglycerides?
Excess sugars and calories
Where are triglycerides stored in the body?
in adipose tissue
How is cholesterol produced?
It is made by the liver and comes from animal dietary sources
How does excess cholesterol affect health?
Excess cholesterol contributes to atherosclerosis
When is cholesterol biosynthesis higher?
Cholesterol biosynthesis is higher in the evening
What are the indications for the use of Penicillin (PCN)?
empiric therapy, respiratory therapy, intra-abdominal infection
What are the adverse effects with Penicillin?
cross-reactivity with cephalosporins allergy
