Hypertension Flashcards
Sympathetic Nervous system
heart rate & contractility
Beta Blockers-beta-adrenergic stimulation.
Decrease stroke volume and lower bp
Propanolol
Calcium channel blockers
Block calcium into the myocardial cells or vascular smooth muscle
A descrease in conttractility, a descreased heart rate and vasoldilation
Ex: nifedipine (Procardia)
Central acting drugs
decrease cardiac output and descrease peripheral resistance. These drugs affect the vasomotor center in the brain by limiting the sympathetic outflow to the heart
Ex: methyldopa (aldomet)
Vascular tone
vasoldilators-alpha adrenergic reptor blockers cause direct vasodilation
Ex: Prazosin
Vascular volume
Diuretics-decrease blood volume and sodium
The different types are classified by what anatomic site in the kidney tuble they exert influence
Three kinds of diuretics
Thiazide diurectics
Loop diuretics
Potassium sparing diuretics
Angiotensis converting Enzyme (ACE) inhibitors
inhibit conversion of angiotensis I into angiotensis II thereby decreasing arterial pressure
Ex: enalapril
Angiotensin receptor blockers
valsartan
Beta blockers
end in olol
Angiotensis receptor blockers
end in “sartin”
Calcium channel blockers
end in “pine”
ACE inhibitors
end in “pril”
beta blockers-Considered 4th line tx in uncomplicated HTN
negative ionotropic effect and used with extreme caution in patients with heart failure
These drugs are cardioselective
Avoid atenolol
Beta blockers
Should be used for 2-3 years after a heart attack.
two most effective are: carvedilol and metoprolol ER
Beta Blockers
Increase triglycerides
Beta 1 predominate in cardiac tissue
Beta 2 predominate in bronchial and vascular smooth muscle and the liver. Both affect bp and Beat 1 have reduced risk of bronchoconstriction
B1 selective
Metoprolol (lopressor) and atenolol
Non selective beta blockers
Timolol and Propanolol
Calcium channel blockers
decreased myocardial contractility, slowed rate of ventricular contractions, coronary artery dilation, and reduced perpheral resistance. They block movement of calcium into the cell membranes of cardiac and smooth muscle
Calcium channel blockers-2 types
dihydropyridines and the non-dihydropyridines
DHP is the largest catefgory
CCBs- dihydropyridines
They do not affect the cardiac conduction system, and thus are not used for cardiac arythmias.
nifedipine, (Procardia), amlodipine (Norvasc)
non-dihydropyridines-Used for hypertension and arrythmias
Verapermil (Calan) and dlitiazem (Cardiazem)
Calcium channel blockers-DO NOT USE IN PATIENTS WITH HEART FAILURE. Cause reflex tacchycardia
Side effects-reflux tachcardia and peripheral edema. Work well with the african american population
Thiazides-used as first choice for most
inhibit reabsorption in the distal tule. Depletes sodium and potassium-conserves calcium. Used for women with osteoporosis. Side effect of hypokalemia. EX: HCT
Loop diurectics
Deplete sodium, potassium, magnesium and calcium in the distal tuble. Most efficient and reserved for those with severe hypertension.
Side effect of hypokalemia, Dangerous if you have heart disease. EX: furosemide (lasix)
Potassium sparing diuretics
Inhibits sodium re-absorption in the collecting duct (as opposed to the distal tubule), sparing potassium. Side effect is most dangerous for clients on ACE inhibitors or those with diabetes or renal impairment
Used in conjuction with thiazide diuretics to counter potassium loss. EX: spironolactone (aldactone)
ACE inhibitors
perevent vasoconstriction of the renal vessles. they potentiate water and sodium loss and tend to spare potassium, making them very effective with a thiazide. Do not combine with potassium sparing for risk of hyperkalemia. ACE’s potentiate BRADYKININ, a vasodilator which enhances insulin sensitivity. Exceelent choice for those with diabetes. In african americans ACEs and ARBs have smaller effects
ACE-examples
Benzapril (Lotensin), Lisinopril
Angiotensin Receptor Blockers (ARBs)
Many advantages of the ACEs only no cough.
They work on AT2 receptors and lead to vasoconstriction., thirst, sodium reabsorption. Blocking the sites decreases vasoconstiction and sodium retention. Have not been studying or available for long. EX: Avapro
Other hypertensives:
Direct vasodilators :hydralazine (Apresoline)
Alpha Blockers: EX: doxazosin (cardura)
Alpha 2 agonists: guanabenz (Wytensin)
Take one hypertensive at night. Not the diuretic
If client is taking three or more, take one at night.
JNC7-tx
Take diuretic first. if not effective add another agent. If the systolic b/p is>160 or diastolic > 100 two agents are needed
ACEs twice as likely for cough in women than men
CCBs more pedal edema in women. Thiazides more likely to cause gou in men. African Americans do not respond well to ACEs but have increased respons to thiazide diuretics
NSAIDS elevate blood pressure when combined with and ACE or ARB
NSAIDS can worsen heart failure
Clients should be counseled not to use
devils claw, ginseng, goldenseal, black licorice, ma huang, squill or yohimbe
While pregnant
bp is lower in the first half of pregnancy. and then increases at the 3rd trimester to pre-pregnancy levels by the end.
ARB and ACE and direct rennin inhibitors (DRI’s) are teratogenic
They are category C in first trimester and D for the remainder. Discontinue if taking. Diuretics and thiazides are contraindicated due to multiple adverse affecdts, decreased plasma volume expansion, reduced amniotic fluid, decreased placental perfusion. Only for pregnant women wit cardiac or renal disease.
ALDOMET (methyldopa)
FDA category B is used the most . Labetalol is category C and used commonly as well.
Beta blockers are the class of anti-hypertensives contraindicated with breastfeeding
Some have been studied like Metoprolol (Lopressor), Propranolol (inderal) and Methyldopa (aldomet) have low levels in breast milk and are considered safe.
Harmful beta blockers while breastfeeding
Atenolol, acebutolol due to extensive secretion in the milk. Some ACE are considered safe in full term babies, but better not to risk.
Calcium channel blockers resul in low breastmilk levels
Prescribe the most studied and safest.
Terbutaline has a selective action on B2 receptors and was used as a drug to delay preterm labor
Due to side effects MgSO4 is currently the preferred drug
Peripheral Alpha 1 blockers-end in azosin
slight decrease in T. Cholesterol, and LDL. Can reduce prostate size so seen given to older men.
