antilipemics lilley, reading & workbook: chap 28 cardiovascular system
TRANSCRIPT
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 DiseasePositive 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 CHDCurrent cigarette smokerHypertension
BP 140/90 or higher, or on antihypertensive medication
Low HDL levels: less than 35 mg/dLDiabetes 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 (HMGs, or statins)
Bile acid sequestrantsNiacin (nicotinic acid)Fibric acid derivativesCholesterol absorption inhibitorCombination 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 disturbancesRashHeadacheMyopathy (muscle pain), possibly leading to
the serious condition rhabdomyolysisElevations 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 actionPrevent resorption of bile acids from small intestineBile acids are necessary for absorption
of cholesterol
IndicationsType II hyperlipoproteinemiaRelief 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 actionIncreases activity of lipase, which breaks down lipidsReduces the metabolism of cholesterol and
triglycerides
IndicationsEffective in lowering triglyceride, total serum
cholesterol, and LDL levelsIncreases HDL levelsEffective in the treatment of types IIa, IIb, III, IV, and
V hyperlipidemias
Fibric Acid Derivatives
Mechanism of actionActivate lipase, which breaks down cholesterolSuppress 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
IndicationsTreatment of types III, IV, and V hyperlipidemias
Drug EffectsDecrease the triglyceride levelsIncrease HDL by as much as 25%
Fibric Acid Derivatives
Adverse effects
Abdominal discomfort, diarrhea, nauseaBlurred vision, headacheIncreased risk of gallstonesProlonged prothrombin timeLiver 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 levelsWorks 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 andmonounsaturated 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.