Sympatholytics(BABs)-ATI pharm Flashcards
BAB’s
Beta Adrenergic Blockers
Meds
Prototypes= 1-Cardioselective: Beta -Metoprolol -Atenolol -Esmolol 2-Nonselective: beta1 and beta2(heart&lungs) -Propranolol -Nadolol 3-Alpha and Beta Blockers -Carvedilol -Labetalol
Expected pharm action
1-cardiac conditions=result of beta1-adrenergic blockade in myocardium and in electrical conduction system of heart
2-decreased HR
3-decreased myocardial contractility;decreases CO
4-decreased rate of conduction through AV node
5-alpha blockade adds vasodilation in meds such as carvedilol and labetalol
6-reduces release of renin;decreases angiotensin II and causes vasodilation and promotes excretion of sodium/water
Therapeutic uses
1-primary hypertension
2-angina,tachydysrhythmias, heart failure,MI
3-suppresses reflex tachycardia due to vasodilators
Other uses:
-hyperthyroidism,migraine,pheochromocytoma,glaucoma
Complications:Beta1 Blockade(Metoprolol/propranolol)
1-bradycardia 2-decreased CO 3-AV block 4-orthostatic hypotension 5-rebound myocardium excitation
Bradycardia
1-monitor pulse, if below 50/min hold med/notify provider
2-use cautiously in pts w/ diabetes,med can mask tachycardia,an early manifestation of low BG
Decreased CO
1-use cautiously w/ pts who have heart failure
2-observe for manifestations of worsening heart failure
AV block
Obtain baseline ECG and monitor
Rebound myocardium excitation
1-myocardium becomes sensitized to catecholamines w/ long term use of beta-blockers
2-do not stop taking beta blockers abruptly, discontinue over 1-2 wks
Complications: Beta2 Blockade(propranolol)
1-Bronchoconstriction=avoid in pts w/ asthma(give them beta1 selective agent)
2-Glycogenolysis is inhibited=pts who have diabetes rely on the breakdown of glycogen into glucose to manage low BG(can happen w/ insulin overdose)
3-decreased HR can mask low BG(pts w/ diabetes should receive a beta1 selective agent)
Contraindications/precautions
-contraindicated with those who AV block and sinus bradycardia
Nonselective=contraindicated in those who have asthma,bronchospasm,&heart failure
Cardioselective=use cautiously in those who have asthma
In general, use cautiously in pts who have myasthenia gravis,hypotension,peripheral vascular disease,diabetes,depression,and older adults who have hx of severe allergies
Interactions:Beta1(metoprolol,propranolol)
1-CCB verapamil/diltiazem intensify effects(decreased HR,myocardial contractility,rate of conduction through AV node)
2-antihypertensive meds=intensifies hypotensive effect of both meds;monitor for drop in BP
Interactions:beta2(propranolol)
1-can mask hypoglycemic effect of insulin and prevent breakdown of fat in response to hypoglycemia;monitor BG levels
Nursing admin
1-orally once or twice a day
2-can be IV=atenolol,metoprolol,labetalol,propranolol
3-do not crush or chew extended release tablets
4-teach pts to self monitor HR and BP at home daily
5-take w/ food to increase absorption
Nursing Evaluation of med effectiveness
1-Absence of chest pain
2-Absence of cardiac dysrhythmias
3-Normotensive BP readings
4-Control of heart failure manifestations