Download Cardiovascular System

Cardiovascular System
ANTILIPEMICS
LILLEY, READING & WORKBOOK: CHAP 28
Antilipemics
Drugs used to lower lipid levels
Triglycerides and Cholesterol
 Two primary forms of lipids in the blood
 Water-insoluble fats that must be bound to
apolipoproteins, specialized lipid-carrying proteins
 Lipoprotein is the combination of triglyceride or
cholesterol with a polipoprotein
Lipoproteins
 Very-low-density lipoprotein (VLDL)
 Produced by the liver
 Transports endogenous lipids to the cells
 Low-density lipoprotein (LDL)
 High-density lipoprotein (HDL)
 Responsible for “recycling” of cholesterol
 Also known as “good cholesterol”
Coronary Heart Disease
The risk of CHD in patients with cholesterol levels of
300 mg/dL is three to four times greater than that in
patients with levels less than 200 mg/dL
Coronary Heart Disease
Positive Risk Factors
 Age
 Male 45 years or older
 Female 55 years or older, or women with premature
menopause not on estrogen replacement therapy
 Family history: history of premature CHD
 Current cigarette smoker
 Hypertension
 BP 140/90 or higher, or on antihypertensive medication
 Low HDL levels: less than 35 mg/dL
 Diabetes mellitus
Treatment Guidelines
 Antilipemic drugs are used as an adjunct to diet
therapy
 Drug choice based on the specific lipid profile of the
patient
 All reasonable non-drug means of controlling blood
cholesterol levels (e.g., diet, exercise) should be tried
for at least 6 months and found to fail before drug
therapy is considered
Antilipemics
 HMG-CoA reductase inhibitors
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(HMGs, or statins)
Bile acid sequestrants
Niacin (nicotinic acid)
Fibric acid derivatives
Cholesterol absorption inhibitor
Combination drugs
Antilipemics: HMG-CoA Reductase
Inhibitors (HMGs, or statins)
Most potent LDL reducers
 lovastatin (Mevacor)
 pravastatin (Pravachol)
 simvastatin (Zocor)
 atorvastatin (Lipitor)
 fluvastatin (Lescol)
HMG-CoA Reductase Inhibitors
(statins)
Indications
 First-line drug therapy for hypercholesterolemia
 Treatment of types IIa and IIb hyperlipidemias
 Reduce LDL levels by 30% to 40%
 Increase HDL levels by 2% to 15%
 Reduce triglycerides by 10% to 30%
HMG-CoA Reductase Inhibitors (statins)
Adverse effects
 Mild, transient GI disturbances
 Rash
 Headache
 Myopathy (muscle pain), possibly leading to the
serious condition rhabdomyolysis
 Elevations in liver enzymes or liver disease
Bile Acid Sequestrants
 cholestyramine (Questran)
 colestipol hydrochloride (Colestid)
 colesevelam (tablet form)
 Also called bile acid–binding resins and
ion-exchange resins
Bile Acid Sequestrants
Mechanism of action
 Prevent resorption of bile acids from small intestine
 Bile acids are necessary for absorption
of cholesterol
Indications
 Type II hyperlipoproteinemia
 Relief of pruritus associated with partial
biliary obstruction (cholestyramine)
 May be used along with statins
Bile Acid Sequestrants
Adverse effects
 Constipation
 Heartburn, nausea, belching, bloating
 These adverse effects tend to disappear over
time
Niacin (Nicotinic Acid)
 Vitamin B3
 Lipid-lowering properties require much higher doses
than when used as a vitamin
 Effective, inexpensive, often used in combination
with other lipid-lowering drugs
Niacin (Nicotinic Acid)
Mechanism of action
 Increases activity of lipase, which breaks down lipids
 Reduces the metabolism of cholesterol and triglycerides
Indications
 Effective in lowering triglyceride, total serum cholesterol,
and LDL levels
 Increases HDL levels
 Effective in the treatment of types IIa, IIb, III, IV, and V
hyperlipidemias
Niacin (Nicotinic Acid)
Adverse effects
 Flushing (due to histamine release)
 Pruritus
 GI distress
Fibric Acid Derivatives
Also known as fibrates
 gemfibrozil (Lopid)
 fenofibrate (Tricor)
Fibric Acid Derivatives
Mechanism of action
 Activate lipase, which breaks down cholesterol
 Suppress release of free fatty acid from the adipose tissue,
inhibit synthesis of triglycerides in the liver, and increase the
secretion of cholesterol in the bile
Indications
 Treatment of types III, IV, and V hyperlipidemias
Drug Effects
 Decrease the triglyceride levels
 Increase HDL by as much as 25%
Fibric Acid Derivatives
Adverse effects
 Abdominal discomfort, diarrhea, nausea
 Blurred vision, headache
 Increased risk of gallstones
 Prolonged prothrombin time
 Liver studies may show increased function
Cholesterol Absorption Inhibitor
ezetimibe (Zetia)
 Inhibits absorption of cholesterol and related
sterols from the small intestine
 Results in reduced total cholesterol, LDL, triglylceride
levels
 Also increases HDL levels
 Works well when taken with a statin drug
Nursing Implications
Patient Education
 Before beginning therapy, obtain a thorough health
and medication history
 Assess dietary patterns, exercise level, weight, height,
VS, tobacco and alcohol use, family history
 Assess for contraindications, conditions that require
cautious use, and drug interactions
Nursing Implications
Patient Education
 Contraindications include biliary obstruction, liver
dysfunction, active liver disease
 Obtain baseline liver function studies
 Patients on long-term therapy may need
supplemental fat-soluble vitamins (A, D, K)
 Take with meals to decrease GI upset
Nursing Implications
Patient Education
 Patient must be counseled concerning diet and nutrition on
an ongoing basis
 Instruct on proper procedure for taking the medications
 Powder forms must be taken with a liquid, mixed
thoroughly but not stirred, and NEVER taken dry
Nursing Implications
Patient Education
 Other medications should be taken 1 hour
before or 4 to 6 hours after meals to avoid
interference with absorption
 Clofibrate often causes constipation; instruct
patients to increase fiber and fluid intake to
offset this effect
Nursing Implications
Patient Education
 To minimize adverse effects of niacin, start on low
initial dose and gradually increase it, and take with
meals
 Small doses of aspirin or NSAIDs may be taken
30 minutes before niacin to minimize cutaneous
flushing
 Inform patients that these drugs may take several
weeks to show effectiveness
Nursing Implications
Patient Education
 Instruct patients to report persistent GI upset,
constipation, abnormal or unusual bleeding, and
yellow discoloration of the skin
 Monitor for adverse effects, including increased liver
enzyme studies
 Monitor for therapeutic effects
 Reduced cholesterol and triglyceride levels
Review
In addition to drug therapy, the patient should be
encouraged to do which of the following to treat
hyperlipidemia? (Select all that apply.)
1. Reduce cholesterol and fats in diet.
2. Reduce weight.
3. Decrease exercise.
4. Increase use of polyunsaturated and
monounsaturated fats.
Review
Before initiating a statin drug, the premedication
assessment should include:
1. complete blood count (CBC).
2. liver function studies.
3. bleeding time.
4. gastrointestinal (GI) series.
Review
Ezetimibe (Zetia) acts by:
1. an unknown mechanism of action.
2. binding bile acids in the intestines.
3. removing fat-soluble vitamins.
4. blocking absorption of cholesterol by
the small intestines.