NRSG 220 Week 6: Alphas, BB and CCB

adrenergic agonists

alpha and beta blockers - block effect of NE at adrenergic receptors

alpha adrenergic antagonists are used to treat

HTN and BPH

first dose phenomenon

- when SNS is blocked, PSNS predominates

- hypotension, orthostatic hypotension (decreased blood to brain and syncope)

- prevention by initial therapy started at low doses and given at bedtime

- reflex tachycardia and nasal congestion

What do selective alpha 1 blockers block?

Peripheral catecholamines

How do selective alpha 1 blockers affect arterioles?

They block vasoconstriction on vascular smooth muscles, which decreases blood pressure.

What effect do selective alpha 1 blockers have on veins?

They block vasoconstriction, which decreases venous return to the heart and lowers blood pressure indirectly.

Can alpha blockers be used concurrently with other drugs?

Yes, they can be used concurrently with drugs like diuretics.

What effect do selective alpha 1 blockers have on smooth muscles of the bladder and prostate?

They relax smooth muscles of the bladder and prostate.

What is the effect of selective alpha 1 blockers on urine flow?

They increase urine flow.

therapeutic uses of alpha 1 blockers

BPH, HTN and pheochromocytoma

BPH and alpha 1 blockers

- 2 selective agents used in BPH

- alfuzosin and tamsulosin

- alpha 1 blockers do not sure condition (need surgery)

alpha 1 blockers and HTN

treat severe HTN

alpha 1 blockers and pheochromocytoma

- small tumor of adrenal medulla (causes irregular secretion of E and NE)

- excessive secretions of catecholamine in this condition causes severe HTN

selective beta adrenergic antagonists (beta blockers)

- block only beta 1

- cardioselective

- fewer non cardiac side effects

- little effect on bronchial smooth muscle

- can be given to client with asthma and COPD

non selective beta adrenergic antagonists (beta blockers)

- block beta 1 and 2

- produce more side effect then selective beta 1 antagonists

- serious SE is bronchoconstriction (caution with COPD and asthma)

therapeutic uses of beta adrenergic antagonists (beta blockers)

- slow conduction velocity through AV node

- decrease HR (chronotropic)

- decrease force of contraction (inotropic)

- during stress/exercise prevent normal SNS stimulation fo heart

- caution when administering CCBs concurrently (potentiate HF)

therapeutic uses of beta blockers

HTN, angina, glaucoma

ADR of beta blockers

- prevent hyperglycaemic effects of catecholamines (dangerous for DM patients, cause and mask hypoglycaemia)

- decrease amount of free FA available during metabolic stress

- bronchoconstriction

- rebound cardiac excitability may occur if stopped abruptly

non-selective beta blockers

work on beta 1 and 2 receptors

considerations for propranolol

- monitor VS q15 min-q1 hour

- hx and px - asthma and COPD

- review lab tests for kidney, liver, hematologic and cardiac functions

- watch for ADRs in older adults and impaired renal function

- monitor intake, output and daily weights

- decrease salt intake

- do not stop suddenly

- examine for impaired circulation - IRR, SOB, BLE, edema

- watch for widening QRS

nonselective beta blockers names

"-olol" and carvedilol and labetalol

what to watch for with sotalol

widening QRS complex

considerations for metoprolol

- monitor BP and HR frequently

- baseline ECG and repeat if elementary changes or CP

- monitor s/s HF

- record input, output, daily weights and bilateral breath sounds

- take radial pule

- do not administer if Hr less then 60 or SBP below 100

- do not omit, increase or decrease dosage

- avoid late evening doses

- watch s/s depression

- watch for masked hyperthyroidism

- report visual problems and cold, painful, tender hands/feet

- cation with DM patients

- discontinue drug slowly

- do stop breast feed without consulting provider

Calcium channel blockers (CCBs) effects

heart and vascular smooth muscle

vascular smooth muscle effects

- prevents contraction fo peripheral arteries

- afterload reduced

- dilation fo coronary arteries

how to CCV reduce after load

decrease peripheral resistance and decreases preload

CCB myocardium effects

reduced force of myocardial contraction (negative inotropic effect) - reduced influx of calcium during plateau phase of action potential

CCB conduction effects

- negative chronotropic effects

- SA node generated few action potentials

- slows automaticity

- decreases HR

nifedipine drug class

Dihydropyridine CCB

nifedipine drug interactions

- may interact with drugs that induce/inhibit CYP3A4

- additive effect with other antihypertensives

- increase risk of BHF and BB

- increase serum dig - bradycardia

- syncope/drop in BP with alcohol

nifedipine OD tx

- rapid acting vasopressors such as dopamine/dobutamine

- calcium infusions

Verapamil drug class

Nondihydropyridine CCB

verapamil drug interactions

- increase dig - bradycardia

- additive hypotension or bradycardia with other antihypertensives

- 3x plasma concentration of busiprone

- risk of myopathy increases significantly with statins

- increases carbsmezipine levels = neurotoxicity

- grapefruit juice may increase levels

verapamil considerations

- monitor BP before admin and 30min-1hour after

- withholding if SBP less than 90 or symptomatic

- monitor for edema

- keep patient recumbent for at least 1 hour after administration

- monitor for heart block or bradycardia with dig use

- monitor intake and output

- monitor elementary continuously if parenteral

drugs similar to verapamil

Diltiazem (Cardizem, Dilacor, Taztia XR, Tiazac)

Treatment of atrial dysrhythmias and HTN, stable and vasospastic angina

Same profile as verapamil

Migraine prophylaxis off-label

diltazem

- tx atrial dysrhythmias, HTN, stable and vasospastic angina

- same profile as verapamil

- migraine prophylaxis

adrenergic antagonists uses

- rest and digest, HTN management, BPH (limited role_