UNIT 4 Cardiovascular System Flashcards
Arrhythmia: Causes
CHF, CAD, MI, drug therapy
Arrhythmia: Symptoms
mild palpitations, cardiac arrest, asymptomatic, fatigue
Arrhythmia: Types
bradycardia, tachycardia, atrial flutter, atrial fibrillation, ventricular fibrillation, premature atrial contraction, premature ventricular contraction
Antiarrhythmics: Goal
return to a normal sinus rhythm;
does not cure the underlying cause;
affects the membrane and movement ions to improve cardiac function
Cardiac Arrest
heart stops beating suddenly
Antiarrhythmics: Classes
Class I: blocks Na+ channels;
Class II: beta blockers
Class III: blocks K+ channels
Class IV: CCBs
Miscellaneous Antiarrhythmic
Antiarrhythmics: Class I
MOA: block Na+ channels, decrease influx of Na+ during repolarization, decrease rate, decrease conduction, prolong refractory period
USES: ventricular and supraventricular arrhythmias
DRUGS: quinidine (Quinaglute)
procainamide (Pronestyl)
lidocaine (Xylocaine)
PATIENT TEACHING/SIDE EFFECTS: N, D, tremors, restlessness, anorexia
Antiarrhythmics: Class II
Beta-Blockers
MOA: bind to beta-1 receptors, slow down HR, slow down velocity of conduction
USES: increased sympathetic nervous system activity; ventricular and supraventricular tachyarrhythmias
DRUGS: propranolol (Inderal) - non-selective beta blocker
PATIENT TEACHING/SIDE EFFECTS: drowsiness, GI upset, CNS depression, mental depression, monitor serum lipid levels, monitor glucose levels in diabetics, bradycardia, do not use with asthma patients - bronchoconstriction
Antiarrhythmics: Class III
K+ channel blockers
MOA: blocks K+ channels, delays repolarization, prolongs refractory period
USES: ventricular tachycardia, ventricular fibrillation
DRUGS: bretylium (Bretylol)
amiodarone (Cordarone) - potent, while others are not effective, contains iodine, may interfere with thyroid fxn
PATIENT TEACHING/SIDE EFFECTS: may affect thyroid fxn - contains iodine, hypotension, dizziness, GI upset, tremors, skin discoloration
Antiarrhythmics: Class IV
CCBs
MOA: blocks entry of Ca2+ into cells; decreases HR and velocity of conduction, decreases FOC (watch our for CHF patients)
USES: tachyarrhythmias (SVT)
DRUGS: verapamil (Calan)
diltiazem (Cardizem)
PATIENT TEACHING/SIDE EFFECTS: hypotension, dizziness, xerostomia, facial flushing, HA, constipation
Miscellaneous Antiarrhythmic
MOA: decreases activity Ca2+ in SA and AV nodes, decreases conduction and rate
DRUGS: adenosine (Adenocard) - emergent or acute situations
USES: SVT
PATIENT TEACHING/SIDE EFFECTS: respiratory difficulty/bronchospasm, hypotension
Anemia
insufficient RBCs or Hbg
insufficient levels of O2
Anemia: Symptoms
weakness, fatigue, increased HR, SOB, pallor, irritability
Anemia: Causes
genetic, blood loss, bone marrow suppression, destruction of RBCs, lack of vitamins and minerals, drugs
Anemia: Types
Iron Deficiency Anemia, Vitamin B12 Anemia/Pernicious Anemia, Folic Acid Deficiency Anemia
Iron Deficiency Anemia (Fe+)
lack of iron causing decreased Hgb
DIET: fish, meat, soy, beans, green veggies
-give supplement (Vitamin C to increase intestinal absorption)
DRUGS: ferrous sulfate
ferrous gluconate
ferrous fumarate
PATIENT TEACHING/SIDE EFFECTS: N, constipation, darkened stools, gastric irritation, discoloration of teeth (use a straw or mix with juice)
Vitamin B12 Deficiency Anemia/Pernicious Anemia
DIET: meats, eggs, milk, seafood
not enough in diet (not common); stomach lacks an intrinsic factor for absorption of the vitamin (B12)
may lead to production of megablastic RBCs (too large and have a short lifespan)
Vitamin B12 USES: DNA synthesis, cell division, RBC production, myelin sheath protection
DRUGS: cyanocabalamin (Vitamin B12)
PATIENT TEACHING/SIDE EFFECTS: invasive, injections are for lifetime, monitor injection site for reactions
Folic Acid Deficiency Anemia
USES OF FOLIC ACID: cell growth, cell reproduction, protein synthesis
DIET: leafy greens, fortified cereals, citrus fruits
-may lead to megablastic anemia (RBCs are too large and have a short lifespan)
DRUGS: folic acid
Erythropoietin (EPO)
protein produced by the kidneys that is responsible RBC production
MOA: increases number of RBCs, increases H&H
DRUG: epoietin alpha (Epogen, Procrit)
PATIENT TEACHING/SIDE EFFECTS: N, D, HA, joint pain
Thromboembolism
moving clot becomes lodged
Coagulation
1) Thromboplastin is an enzyme that secreted by platelets (clotting factors); it is a tissue extract (substance released from injured cells)
2) Prothrombin is converted into thrombin with the use of thromboplastin
3) Thrombin converts fibrinogen into fibrin (a mesh responsible for forming a clot; it folds platelets together; is the main component of a clot)
Ca2+ and K+ are required for formation and functioning of clotting factors
4) Plasminogen is converted into plasmin by tissue plasminogen activator (tPA);
plasmin - an enzyme that makes fibrin a more soluble product
5) balance between clot formation and clot breakdown occurs due to homeostasis
Anticoagulants
used against clot formation when the clotting mechanism becomes too active
USES: Deep Vein Thrombosis, Thrombophlebitis, Pulmonary Embolism, Stroke, MI, atrial fibrillation
Anticoagulants: Types
1) High Molecular Weight
2) Low Molecular Weight
3) Oral Vitamin K Antagonist
Anticoagulants: High Molecular Weight
MOA: interferes with platelet aggregation; binds to platelets and thromboplastin, preventing thrombin formation
given IV and SubQ
do not administer IM (hematoma) or orally (too acidic for stomach)
do not cross placenta
antidote: protamine sulfate
DRUGS: heparin
PATIENT TEACHING/SIDE EFFECTS: risk for hemorrhage, alopecia, thrombocytopenia, osteoporosis, fever, petechiae, do not massage the injection site, rotate the injection, do not administer where there is bruising from previous injection, epistaxis, easy bruising
Anticoagulants: Low Molecular Weight
MOA: binds to factor X
DRUGS: enoxaparin (Lovenox)
given subQ
does not cross placenta
antidote: protamine sulfate
PATIENT TEACHING/SIDE EFFECTS: risk for hemorrhage, petechiae, do not massage the injection site, rotate the injection, do not administer where there is bruising from previous injections, easy bruising
Anticoagulants: Vitamin K Antagonist
MOA: prevents formation of platelets and prothrombin;
slow onset, long duration of action (oral)
benefits: oral administration, inexpensive
antidote: Vitamin K
DRUG: warfarin (Coumadin)
PATIENT TEACHING/SIDE EFFECTS: easy bruising, bleeding of the gums, N, V, HA, hematuria, fatigue, cannot administer during pregnancy, epistaxis
