Download M06 Antihypertensives

Antihypertensive
Lori Kenavan
NUR- 304 Pharmacology
Prof. Lynn McNall
Fall 2012
ESC
Learning objectives
• Describe the role of Antihypertensives and its actions.
• Discuss whom receives Antihypertensive medications.
• List categories and subcategories of Antihypertensive
Drugs.
Classification
• Drugs used in the management of primary HTN
belong to several different groups:
•
•
•
•
•
Angiotensin-converting enzyme ACE inhibitors
Angiotension II receptor blockers ARBS
Calcium channel blockers
Diuretics
Vasodilators
These drugs act to decrease blood pressure by
decreasing cardiac output or peripheral vascular
resistance.
Introduction
Hypertension
> 140 mmHg
> 90 mmHg
Systolic Blood
Pressure (SBP)
Diastolic Blood
Pressure (DBP)
HTN
Types of
Hypertension
Essential
Secondary
A disorder of unknown origin affecting the
Blood Pressure regulating mechanisms
Secondary to other disease processes
Environmental
Factors
Stress
Na+ Intake
Obesity
Smoking
WHY TREAT HTN?
• Treatment is mandatory when symptomatic:
• Damage to the vascular epithelium, paving the path for
atherosclerosis (CVA) or nephropathy due to high intraglomerular pressure.
• Increased load on heart due to high BP. Can cause CHF.
• HTN, even asymptomatic needs interventions.
Antihypertensive Drugs and
Its mechanism of Action
• Diuretics:
• Thiazides: Hydrochlorothiazide, chlorthalidone
• High ceiling: Furosemide
• K+ sparing: Spironolactone, triamterene and amiloride
MOA: Acts on Kidneys to increase excretion of Na and
H2O- decrease in blood volume = decreased BP.
Angiotensin- converting Enzyme (ACE) inhibitors:
• Captopril, lisinopril, enalapril, ramipril and fosinopril
M0A: Inhibit synthesis of Angiotensin II- decrease in
peripheral resistance and blood volume.
Angiotensin (AT1) blockers:
• Losartan, candesartan, valsartan and telmisartan
Anti-HTN M.O.A
•
MOA: Blocks binding of Angiotensin II to its receptors.
• Centrally acting:
-Clonidine, methyldopa
• MOA: Act on central receptors to decrease sympathetic
outflow- fall in BP
•
B-adrenergic blockers:
Non-selective: Propranolol (nadolol, timolol, pindolol,
labetolol)
Cardioselective: Metoprolol (atenolol, esmolol, betaxolol)
• MOA: Bind to beta adrenergic receptors and blocks the
activity
B and a- adrenic blockers:
Labetolol and carvedilol
a-adrenergic blockers:
Prazosin, terazosin, doxazosin, phenoxybenzamine and
phentolmine.
Anti-htn m.o.a
• MOA: Blocking of alpha adrenergic receptors in
smooth muscles- vasodilation.
• Calcium Channel Blockers (CCB):
• Verapamil, diltiazem, nifedipine, felodipine, amlodipine,
nimodipine etc.
• MOA: Blocks influx of Ca++ in smooth muscle cellsrelaxation of SMCs = decrease BP
• K+ Chanel activators:
• Diazoxide, minoxidil, pinacidil and nicorandil
Anti-Htn M.O.a
• MOA: Leaking of K+ due to opening- hyper
polarization of SMCs = relaxation of SMCs
• Vasodilators:
• Arteriolar- Hydralazine (also CCB and K+ channel
activators)
• Arterio- venular: Sodium Nitroprusside.
antihypertensives
Indications for use
1. Significant hypertension
• Infants >80 mm Hg DBP
• Children >86 mm Hg DBP
• Adolescents >90 mm Hg DBP
2. Evidence of target organ damage
3. Symptoms or signs related to elevated blood pressure
Allergic and adverse
effects
• Common side effects:
• slight dizziness, fatigue, cough and headache.
• Serious side effects:
• insomnia, decreased sex drive, shortness of breath and
depressed mood.
Contact physician and stop medication.
• Severe side effects:
• chest pain, difficulty breathing, fainting, irregular
heartbeat and rash. Swelling of the face, lips, tongue or
extremities may be the sign of an allergic reaction to the
medication. For these symptoms, treatment should not be
delayed and seek medical help.
Choice of drug
• Choice of drugs in treating hypertension:
• Patients with diabetes – ACEI
• Patients with congestive heart failure or left ventricular dysfunction- ACEI
• Patients with angina pectoris – a beta adrenoceptor blocker
• Patients with migraine - a beta adrenoceptor blocker
• Patients with myocardial infarction – a beta adrenoceptor blocker, ACEI
• Patients with hyperlipidemia – ACEIs, -adrenoceptor antagonists, and
Ca channel blockers
• Black patients – diuretics and Ca channel blockers are more effective
Older patients with isolated systolic hypertension – diuretics,
dihydropyridine Ca channel blockers.
Some Herbal
Solutions
• Garlic - Garlic is beneficial for those with hypertension. By thinning the
blood garlic can lower blood pressure by 5 to 10 percent. It can also lower
cholesterol and discourage clot formation. Unfortunately, garlic has a
reputation for being an "anti-social" food, but with all of the health benefits
that garlic provides, bad breath should be the least of your worries.
• Fish oil – Fish oil may have a modest effect on high blood pressure.
Although fish oil supplements often contain both DHA (docohexaenoic
acid) and EPA (eicosapentaenoice acid), there is some evidence that DHA is
the ingredient that lowers high blood pressure.
• Folic acid - Folate is a B vitamin necessary for formation of red blood cells.
It may help to lower high blood pressure in some people, possibly by
reducing elevated homocysteine levels. One small study of 24 cigarette
smokers found that four weeks of folic acid supplementation significantly
lowered blood pressure.
Herbal cont.
• There are many more such as: Vit C, Celery, Cayenne,
Ayurveda, Black Cumin Seeds, Rauwolfia serpentina,
Ca Mg K, high fiber foods, seaweeds.
• Avoid natural licorice products.
Yoga and
meditation
• Yoga can fight off the causes of the abnormal blood
pressure. It helps both type of blood pressure and stabilizes
blood pressure.
• Some yoga poses for high blood pressure include- Easy Pose
(Sukhasana), Shoulder Stretches, Stand spread leg forward
fold, Cat Pose (Bidalasana) and many more.
• If you do transcendental meditation, it reduces your blood
pressure as it decreases the constriction of the blood vessels.
• By doing meditation daily, you not only keep your blood
pressure under control but also avoid the complications that
you might develop because of hypertension. So, meditation
is one of the best ways to prevent and treat your abnormal
BP!
Dietary Solutions
• A low sodium low calorie diet.
• Hydration is key. Adequate fluid intake is necessary.
• Limit alcohol use.
• Watch intake of Grapefruit: can potentiate
antihypertensives- Calcium channel blockers.
O.T.C
• Many over-the-counter painkillers can push blood pressure
higher.
• Some types of nonsteroidal anti-inflammatory drugs
(NSAIDs) can be risky.
• ibuprofen., naproxen sodium, and ketoprofen, the active
ingredients in meds like Advil and Aleve.
• Some of these NSAIDs reduce the blood flow to the
kidneys. The kidneys -- which filter your blood -- work more
slowly, and so fluid builds up in your body. The increased
fluid drives up your blood pressure.
• Other options: Ice packs, heat, physical activity, relaxation,
acupuncture.
Nursing considerations:
Diuretics
• Diuretics can increase serum glucose and cholesterol
levels, monitor for hyperglycemia and
hypercholesterolemia.
• Teach patients to take diuretics in the morning to avoid
nocturnal diuresis and urination.
• Caution patients to stand up slowly to minimize the
risk of dizziness from orthostatic hypotension.
• Monitor for signs of hypokalemia, such as muscle
weakness and changes in mental status, including
confusion and irritability.
NC: Diuretics con’t.
• Patients taking a potassium-sparing diuretic are at risk
for hyperkalemia. The risk is especially high in patients
also taking an angiotensin-converting enzyme (ACE)
inhibitor.
• Weigh patients daily at the same time using the same
scale. Report a significant weight gain, 3 pounds in 3
days.
• Remind your patient that even if he feels fine, he
should keep appointments with the healthcare provider
because renal function must be monitored.
Nursing Considerations
Beta-Blockers
• Teach patients that they shouldn’t suddenly stop therapy
because of the risk of rebound tachycardia and
hypertension.
• Beta blockers can cause transient increases in serum lipid
and glucose levels.
• Monitor for symptoms of hypoglycemia in patients with
diabetes who use insulin.
• Some older beta blockers such as propranolol can cause
bronchoconstriction and asthma symptoms.
• Check for common adverse effects of beta blockers, such as
dizziness, slowing of the pulse, fatigue, and hypotension.
Nursing Considerations
alpha-blockers
• Warn patients about the risk of orthostatic
hypotension, which can cause falls.
• Teach patients to take their first dose at bedtime and to
move slowly from a sitting to a standing position.
Nursing Considerations
calcium channel blockers
• Tell patients to report dizziness and symptoms of an
irregular heart rate.
• Teach your patients to avoid grapefruit juice because it
inhibits the hepatic metabolism of calcium channel
blockers and may lead to increased blood drug levels
and increased pharmacologic effects.
• All calcium channel blockers should be used cautiously
in patients with heart failure.
Nursing Considerations
ACE-Inhibitors and
angiotensions
• Assess patient for hyperkalemia.
• Rare adverse effects include: agranulocytosis,
proteinuria, glomerulonephritis, acute kidney failure,
and angioedema.
• Assess for angioedema, which can lead to airway
swelling and requires emergent treatment.
• A history of angioedema contraindicates the use of
ACE inhibitors.
Nursing
Considerations
• Tell patients not to stop taking these drugs on their own because an
abrupt withdrawal can result in rebound hypertension.
• Teach to take own blood pressure daily and record it, bringing the
record to scheduled clinic visits.
• Teach name, dose, action, and side effects of
antihypertensive medication.
•
Instruct patient to develop a daily exercise routine.
•
Discuss strategies for maintaining a healthy weight.
• Refer for a dietary consultation for further teaching about the DASH
diet.
• Discuss stress-reducing techniques, helping identify possible choices.
Video’s
• http://youtu.be/4jRy-YlZONA
(Understanding HTN)
• http://youtu.be/9zTFVmUK1gk
(Antihypertensive Meds)
• http://youtu.be/wqJA2FfTPwk
(Guide to lowering HTN)
PLEASE CLICK ON LINK’S
FOR SHORT VIDEOS
Questions
• 1. When giving antihypertensive drugs, the nurse must
consider giving the first dose at bedtime for which of
the fallowing classes of drugs?
A.
B.
C.
D.
a-Blockers such as prazosin (Minipress)
Diuretics such as furosemide (Lasix)
ACE inhibitors such as captopril (Capoten)
Vasodilators such as hydralazine (Apresoline)
Questions
• 2. A 56 yr. old man started anti-hypertensive drug therapy 3
months earlier and is in the office for a follow- up visit.
While the nurse is taking his blood pressure, he informs the
nurse that he has had some problems with sexual
intercourse. Which of the following would be the most
appropriate response by the nurse?
A. “Not to worry. Tolerance will develop”
B. “The physician can work with you on changing the dose
and/or drugs”
C. “Sexual dysfunction happens with this therapy, and you must
learn to accept it.”
D. “This is an unusual occurance, but it is important to stay on
your medications.”
Questions
• 3. Which of the following adverse effects is most
concern for the older adult patient taking
antihypertensive drugs?
A.
B.
C.
D.
Dry mouth
Hypotension
Restlessness
Constipation
References
Abrams, A.C., Pennington, S.S., & Lammon, C.B. (2009). Clinical
Drug Therapy; Rationales for Nursing Practice. (9th ed).
Philadelphia, PA: Wolters Kluwer. Lippincott Williams &
Wilkins.
Frohlich E.D., Apstein C., Chobanian A.V., et al. (1992) The heart
in hypertension. New Engl J Med 327:998–1008.
Ganau A., Devereux R.B., Roman M.J., et al. (1992). Patterns
of left ventricular hypertrophy and geometric
remodelling in essential hypertension. J Am Coll Cardiol
19:1550–1558.
Koffland M.J.M., van der Lee C., ten Cate F.J., Roelandt J.R.T.C.
(1998). Hypertrophic cardiomyopathy: update and new
perspectives. Cardiologie 5:511–524.
References
Pegram B.L., Ishise S., Frohlich E.D. (1982). Effect of methyldopa,
clonidine and hydralazine on cardiac mass and
haemodynamics in Wistar Kyoto and spontaneously
hypertensive rats. Cardiovasc Res 16:40–46.
Pluim B.M., Vliegen H.W., van der Laarse A., van der Wall E.E.
(1998). Pathological left ventricular hypertrophy. Cardiologie
5:574–582.
Savage D.D., Garrison R.J., Kannel W.B., et al. (1987). The
spectrum of left ventricular hypertrophy in a general
population sample: the Framingham study. Circulation
75(suppl.I):I26–I33.
Spirito P., Pelliccia A., Proschan M.A., et al. (1994). Morphology of
the ‘athlete's heart’ assessed by echocardiography in 947
elite athletes representing 27 sports. Am J Cardiol 74:802–806.