Pharmacology Exam 3
HMG-CoA Reductase Inhibitors Prototype: Atorvastatin (Lipitor)
MOA: Blocks HMG-CoA reductase from completing synthesis of cholesterol in the liver (lowers cholesterol)
Admin: At HS (highest rates cholesterol synthesis)
Caution: Renal impairment, liver disease, heavy alcohol use, pregnancy category X
AE: GI effects (cramping, diarrhea, constipation), liver damage, myalgias; toxic: rhabdomyolysis with AKI
Nursing: Monitor liver and kidney function (toxicity); teach to report myalgias, no grapefruit juices (increases
levels-toxicity), lifestyle modification
Antiplatelet Agent/Salicylate Prototype: Aspirin (ASA)
MOA: Inhibit platelet aggregation (COX inhibitor)
Indication: Prevention of MI, TIA, ischemic CVA in high-risk populations (primary or secondary prevention)
Dose: 81-325mg PO daily (81mg is a “baby aspirin”)
AE: GI irritation (N/V, epigastric pain); bleeding – GI bleeding, hematuria, easy bruising; tinnitus (with toxicity)
Nursing: Take as directed, take with food, hold 1 week prior to procedure, monitor for s/s GI bleed (dark/bloody
stools)
Antiplatelet Agent Prototype: Clopidogrel (Plavix)
MOA: Inhibit platelet aggregation (alters signaling)
Indications: Prevent blood clot with hx of MI, ischemic stroke, or PAD; prevent clot with cardiac stent or graft
AE: Bleeding, flulike syndrome, dizziness, bruising, rash, pruritus
Nursing: Hold 5 days prior to procedure, bleeding precautions
Nursing Considerations/Antiplatelet Agents
Assessment
- Indication for medication (prevention blood clots)
- Clinical manifestations of bleeding
Interventions
- Bleeding precautions
- Avoid injury and falls
- Hold prior to procedure/surgery
- Educate patient on medication
Anticoagulants
Disrupt clotting cascade making it difficult for blood to clot
(They do not break up blood clot – they prevent them from growing)
Clotting Disorders/Complications/Treatment Goals
Clotting Disorder Chronic atrial Ischemic stroke Deep vein thrombosis Pulmonary embolism
fibrillation (embolus) (DVT) (PE)
Complication Ischemic stroke Tissue hypoxia/death Pulmonary embolism Tissue hypoxia/death
(embolus) (PE)
Treatment goals Prevent blood clot in Clot lysis: restore Slow clot growth: Slow clot growth:
atria perfusion inhibit propagation; inhibit new clots; clot
inhibits new clots lysis – surgical
,Diagnostic Lab: Clotting Time
Test Ref. Range Significance for Pharmacology
Prothrombin time (PT): Measures 11-12.5 seconds Prolonged: Warfarin therapy
clotting time of extrinsic pathway;
clotting factors II, V, VII, X
International Normalized Ratio (INR) 0.7-1.8 Measurement for adjusting warfarin
therapy
Therapeutic goal: 2.0-3.0
Activated Partial Thromboplastin 21-35 seconds Prolonged: Heparin therapy
Time (aPTT): Assess intrinsic clotting Measurement for adjusting heparin
cascade; clotting factors II, V, VIII, therapy
IX, XI, XII Therapeutic goal: 45-70 seconds
Anticoagulants/Thrombolytics: General Nursing Considerations
All anticoagulants have adverse effect of bleeding (non-fatal and fatal)
- Non-fatal: hematuria, epistaxis, bruising
- Fatal: hemorrhagic stroke, internal bleeding, GI bleeding (older adult high risk)
Reduce risk for injury and falls
Implement bleeding precautions
Contraindications:
- Pregnancy (except heparin/enoxaparin), bleeding disorders, hx of bleed, thrombocytopenia
Drug-drug:
- Antiplatelet agents, NSAIDS, herbals (all increase bleeding)
Indirect Thrombin Inhibitor (Anticoagulant) Prototype: Heparin
MOA: Disrupts clotting cascade; prolongs bleeding time
Route/Dose: 5000 units SQ 8 hours (prevention) or IV drip (protocol)
Indications: Prevent or treat DVT (SQ); treat PE (IV)
Contraindication: Pork allergy; pork abstention religion (Judaism, Muslim)
AE: Bleeding, heparin-induce thrombocytopenia (HIT), bruising at injection site
& usually long term symptom
Nursing: Rotate/monitor injection sites for SQ (do not admin IM), monitor platelet count; monitor aPTT (45-70 sec)
Reversal agent: Protamine sulfate (heparin short half-life, stop infusion)
Low Molecular Weight Heparin (Anticoagulant) Prototype: Enoxaparin (Lovenox)
MOA: Disrupts clotting cascade; prolongs bleeding time
Indications: Prevention or treatment of DVT
Route: 1mg/kg every 12 hours SQ longer given
half life so doesn't have to be
as
,
often as heparin
Contraindication: Pork allergy, pork abstention religion (Judaism, Muslim)
AE: Bleeding; bruising as injection site
Nursing: Admin deep SQ; do not aspirate or massage site; do not remove air bubble from prefilled syringe;
rotate/monitor injection site; monitoring of clotting time not necessary
Reversal agent: Protamine sulfate
Vitamin K Antagonist (Anticoagulant) Prototype: Warfarin (Coumadin)
MOA: Interfere with hepatic synthesis of vitamin K – dependent clotting factors; prolongs bleeding time
Route/Dose: 2-10 mg/day PO based on INR level
Indications: Chronic a-fib; artificial heart valves; prevent/treat DVT/PE
AE: GI effects (n/v), bleeding
Drug-drug: Antibiotics (monitor INR during therapy), amiodarone, herbals
Nursing: Monitor PT/INR (therapeutic INR 2.0-3.0); first oral anticoagulant drug on market
Reversal Agent: Vitamin K
, Warfarin Special Consideration
Dosing
- Daily (usually in the evening)
- If INR is greater than 3.0; HOLD and call prescribing provider
- Expect an order for vitamin K if INR is greater than 4.0 (PO or SQ)
Lab draws
- Dose change = next lab in 3 days
- Long term monitoring = weekly or monthly
Diet
- Teach patient to maintain consistent intake (avoid) vitamin K containing foods (high intake may decrease
warfarin effect)
Herbals to Avoid with Warfarin
St. Johns Wart
Garlic
Gingko
Ginger root
Chamomile
Factor Xa Inhibitor (Anticoagulant) Prototype: Rivaroxaban (Xarelto)
MOA: Disrupt clotting cascade; prolongs bleeding time
Route/Dose: 10mg PO daily (prevention); 15mg PO BID (treatment)
Indications: Chronic a-fib; prevent DVT and PE
AE: Bleeding
Nursing: No blood monitoring required
Reversal agent: Andexxa
Initial Management Anticoagulant Overdose
Assessment
-
Clinical manifestations of bleeding and vital signs (HR/BP/O2 sat)
Interventions
- Notify provider
- Draw labs as ordered: Hemoglobin/hematocrit (bleeding); platelets (bleeding, HIT); clotting times (PT/INR,
aPTT)
- Administer fluids (normal saline) and/or packed red blood cells as ordered
- Administer reversal agent as ordered
Thrombolytic Agent Prototype: Alteplase (Activase; tPA)
MOA: Local fibrinolysis (acute clot lysis)
Indications: Systemic; ischemic (embolic) stroke, PE, coronary thrombosis (MI); local: central venous catheter
occlusion
AE: Bleeding, hypotension, bradycardia, tachycardia
Contraindications: Many
Drugs Affecting Blood Coagulation: Nursing Assessment/Diagnosis/Outcomes
Assessment:
- Physical assessment with focus on cardiovascular and s/s bleeding
HMG-CoA Reductase Inhibitors Prototype: Atorvastatin (Lipitor)
MOA: Blocks HMG-CoA reductase from completing synthesis of cholesterol in the liver (lowers cholesterol)
Admin: At HS (highest rates cholesterol synthesis)
Caution: Renal impairment, liver disease, heavy alcohol use, pregnancy category X
AE: GI effects (cramping, diarrhea, constipation), liver damage, myalgias; toxic: rhabdomyolysis with AKI
Nursing: Monitor liver and kidney function (toxicity); teach to report myalgias, no grapefruit juices (increases
levels-toxicity), lifestyle modification
Antiplatelet Agent/Salicylate Prototype: Aspirin (ASA)
MOA: Inhibit platelet aggregation (COX inhibitor)
Indication: Prevention of MI, TIA, ischemic CVA in high-risk populations (primary or secondary prevention)
Dose: 81-325mg PO daily (81mg is a “baby aspirin”)
AE: GI irritation (N/V, epigastric pain); bleeding – GI bleeding, hematuria, easy bruising; tinnitus (with toxicity)
Nursing: Take as directed, take with food, hold 1 week prior to procedure, monitor for s/s GI bleed (dark/bloody
stools)
Antiplatelet Agent Prototype: Clopidogrel (Plavix)
MOA: Inhibit platelet aggregation (alters signaling)
Indications: Prevent blood clot with hx of MI, ischemic stroke, or PAD; prevent clot with cardiac stent or graft
AE: Bleeding, flulike syndrome, dizziness, bruising, rash, pruritus
Nursing: Hold 5 days prior to procedure, bleeding precautions
Nursing Considerations/Antiplatelet Agents
Assessment
- Indication for medication (prevention blood clots)
- Clinical manifestations of bleeding
Interventions
- Bleeding precautions
- Avoid injury and falls
- Hold prior to procedure/surgery
- Educate patient on medication
Anticoagulants
Disrupt clotting cascade making it difficult for blood to clot
(They do not break up blood clot – they prevent them from growing)
Clotting Disorders/Complications/Treatment Goals
Clotting Disorder Chronic atrial Ischemic stroke Deep vein thrombosis Pulmonary embolism
fibrillation (embolus) (DVT) (PE)
Complication Ischemic stroke Tissue hypoxia/death Pulmonary embolism Tissue hypoxia/death
(embolus) (PE)
Treatment goals Prevent blood clot in Clot lysis: restore Slow clot growth: Slow clot growth:
atria perfusion inhibit propagation; inhibit new clots; clot
inhibits new clots lysis – surgical
,Diagnostic Lab: Clotting Time
Test Ref. Range Significance for Pharmacology
Prothrombin time (PT): Measures 11-12.5 seconds Prolonged: Warfarin therapy
clotting time of extrinsic pathway;
clotting factors II, V, VII, X
International Normalized Ratio (INR) 0.7-1.8 Measurement for adjusting warfarin
therapy
Therapeutic goal: 2.0-3.0
Activated Partial Thromboplastin 21-35 seconds Prolonged: Heparin therapy
Time (aPTT): Assess intrinsic clotting Measurement for adjusting heparin
cascade; clotting factors II, V, VIII, therapy
IX, XI, XII Therapeutic goal: 45-70 seconds
Anticoagulants/Thrombolytics: General Nursing Considerations
All anticoagulants have adverse effect of bleeding (non-fatal and fatal)
- Non-fatal: hematuria, epistaxis, bruising
- Fatal: hemorrhagic stroke, internal bleeding, GI bleeding (older adult high risk)
Reduce risk for injury and falls
Implement bleeding precautions
Contraindications:
- Pregnancy (except heparin/enoxaparin), bleeding disorders, hx of bleed, thrombocytopenia
Drug-drug:
- Antiplatelet agents, NSAIDS, herbals (all increase bleeding)
Indirect Thrombin Inhibitor (Anticoagulant) Prototype: Heparin
MOA: Disrupts clotting cascade; prolongs bleeding time
Route/Dose: 5000 units SQ 8 hours (prevention) or IV drip (protocol)
Indications: Prevent or treat DVT (SQ); treat PE (IV)
Contraindication: Pork allergy; pork abstention religion (Judaism, Muslim)
AE: Bleeding, heparin-induce thrombocytopenia (HIT), bruising at injection site
& usually long term symptom
Nursing: Rotate/monitor injection sites for SQ (do not admin IM), monitor platelet count; monitor aPTT (45-70 sec)
Reversal agent: Protamine sulfate (heparin short half-life, stop infusion)
Low Molecular Weight Heparin (Anticoagulant) Prototype: Enoxaparin (Lovenox)
MOA: Disrupts clotting cascade; prolongs bleeding time
Indications: Prevention or treatment of DVT
Route: 1mg/kg every 12 hours SQ longer given
half life so doesn't have to be
as
,
often as heparin
Contraindication: Pork allergy, pork abstention religion (Judaism, Muslim)
AE: Bleeding; bruising as injection site
Nursing: Admin deep SQ; do not aspirate or massage site; do not remove air bubble from prefilled syringe;
rotate/monitor injection site; monitoring of clotting time not necessary
Reversal agent: Protamine sulfate
Vitamin K Antagonist (Anticoagulant) Prototype: Warfarin (Coumadin)
MOA: Interfere with hepatic synthesis of vitamin K – dependent clotting factors; prolongs bleeding time
Route/Dose: 2-10 mg/day PO based on INR level
Indications: Chronic a-fib; artificial heart valves; prevent/treat DVT/PE
AE: GI effects (n/v), bleeding
Drug-drug: Antibiotics (monitor INR during therapy), amiodarone, herbals
Nursing: Monitor PT/INR (therapeutic INR 2.0-3.0); first oral anticoagulant drug on market
Reversal Agent: Vitamin K
, Warfarin Special Consideration
Dosing
- Daily (usually in the evening)
- If INR is greater than 3.0; HOLD and call prescribing provider
- Expect an order for vitamin K if INR is greater than 4.0 (PO or SQ)
Lab draws
- Dose change = next lab in 3 days
- Long term monitoring = weekly or monthly
Diet
- Teach patient to maintain consistent intake (avoid) vitamin K containing foods (high intake may decrease
warfarin effect)
Herbals to Avoid with Warfarin
St. Johns Wart
Garlic
Gingko
Ginger root
Chamomile
Factor Xa Inhibitor (Anticoagulant) Prototype: Rivaroxaban (Xarelto)
MOA: Disrupt clotting cascade; prolongs bleeding time
Route/Dose: 10mg PO daily (prevention); 15mg PO BID (treatment)
Indications: Chronic a-fib; prevent DVT and PE
AE: Bleeding
Nursing: No blood monitoring required
Reversal agent: Andexxa
Initial Management Anticoagulant Overdose
Assessment
-
Clinical manifestations of bleeding and vital signs (HR/BP/O2 sat)
Interventions
- Notify provider
- Draw labs as ordered: Hemoglobin/hematocrit (bleeding); platelets (bleeding, HIT); clotting times (PT/INR,
aPTT)
- Administer fluids (normal saline) and/or packed red blood cells as ordered
- Administer reversal agent as ordered
Thrombolytic Agent Prototype: Alteplase (Activase; tPA)
MOA: Local fibrinolysis (acute clot lysis)
Indications: Systemic; ischemic (embolic) stroke, PE, coronary thrombosis (MI); local: central venous catheter
occlusion
AE: Bleeding, hypotension, bradycardia, tachycardia
Contraindications: Many
Drugs Affecting Blood Coagulation: Nursing Assessment/Diagnosis/Outcomes
Assessment:
- Physical assessment with focus on cardiovascular and s/s bleeding
