UAB NUR 328: Pharmacology- Perfusion Drugs

how can blood pressure be calculated?

cardiac output x peripheral resistance

what is cardiac output?

heart rate x stroke volume; preload + force of contraction

what is peripheral resistance?

vasoconstriction or lack of vasodilation

what system controls peripheral resistance?

renal; RAAS system

what is primary hypertension?

elevated BP without an identified cause

what is secondary hypertension?

elevated BP with a specific cause

what percent of people with hypertension have primary hypertension?

90%

what is recommended for all patients with hypertension?

medication; all patients with HTN get started on a medication

what is the diagnostic number for hypertension?

140/90

what is good patient education for a patient with hypertension?

diet, exercise

if a patient has acute or chronic renal disease, would their medication dosage be higher or lower?

lower; meds could accumulate and cause toxicity

if a patient has diabetes, why might their medication dosage be different?

diabetes causes vasoconstriction

what patients are more at risk for hypertension?

African Americans, Asians, women (birth control- estrogen vasoconstricts), children and adolescents, elderly (organs are very matured and function poorly)

why can adherence be so difficult to achieve for patients on blood pressure medications?

they may stop their medication if they see that their BP is fixed; they may have side effects that make them feel groggy, dizzy, sexual function sometimes decreases

what are ways to ensure that patients still to their blood pressure medication regimen?

educate the patient, teach self-monitoring, minimize side effects, establish a collaborative relationship, simplify the regimen, reduce cost

how do medications treat hypertension?

reduces circulating volume/edema with diuretics and reduces vasoconstriction of vessels with ACE inhibitors, ARBS, beta blockers, CCBs, and alpha 1 blockers

hypertension is one of the leading causes of what in the brain?

subarachnoid hemorrhages

how long does it take for blood pressure medicine to be in full effect?

4-6 weeks

what time of day should a patient be taking a diuretic?

early morning

what are the COMMON adverse effects of diuretics?

orthostatic hypotension, hypovolemia, fluid & electrolyte imbalances (obtain baseline values for fluid and electrolytes before administering)

what patient population are diuretics cautioned in?

elderly; patients with previous fluid and electrolyte imbalances

what are the therapeutic effects of diuretics?

decreased blood pressure, reduction in edema, decreased dyspnea, diminished crackles in the lungs

what patient teaching do we need to ensure before administering a diuretic?

diet (avoid sodium intake), safety, labs (potassium, magnesium, calcium, sodium, chloride)

what is the prototype of thiazide diuretics?

hydrochlorothiazide

what is the mechanism of action of hydrochlorothiazide?

acts in the distal tubule of the kidney; decreases Na, Cl, and water reabsorption

what is the use of hydrochlorothiazide?

used for long term treatment of heart failure, mild hypertension, and moderate edema

what is hydrochlorothiazide contraindicated with?

sulfa allergies

what is hydrochlorothiazide cautioned with?

patients with renal disease, liver disease, pregnancy, gout, diabetes, lupus

what does hydrochlorothiazide increase?

uric acid levels (relates to gout), blood glucose, risk for kidney disease

patients must have a GFR greater than what in order to administer hydrochlorothiazide?

greater than 30

what is a normal GFR?

greater than 60 mL/min

what are the adverse effects of hydrochlorothiazide?

-electrolyte imbalances:

Ca increases

BG increases

uric acid increases

Na decreases

K decreases

Cl decreases

-muscle cramps

what are the drug interactions of hydrochlorothiazide?

alcohol and beta blockers increase effect of the diuretic, digoxin and lithium increase risk of digoxin toxicity and lithium toxicity, NSAIDs, cholestyramine decreases effectiveness of the diuretic

what are the therapeutic effects of hydrochlorothiazide?

decreases edema, SOB, and sets BP within normal limits

what is a ceiling threshold?

max potential of a certain dose that is individualized for each person; no matter what you raise the dose to it will not work

what are nursing implications for hydrochlorothiazide?

ceiling threshold and labs

what medications might a patient need to take along with hydrochlorothiazide (in terms of HCTZ increasing blood glucose)?

anti diabetic medications/blood sugar medications

what is the prototype for loop diuretics?

furosemide

what is the mechanism of action for furosemide?

acts in the ascending loop of Henle and inhibits reabsorption of Na, Cl, and H2O

what is furosemide used for?

pulmonary edema, hypertension, heart failure, ascites

why are loop diuretics the most common type of diuretic?

they are the most effective and they have rapid effects

what route is furosemide administered?

oral/IV

what is furosemide contraindicated with?

hepatic coma (makes it worse)

what is furosemide cautioned with?

kidney disease, liver disease, pregnancy, gout, diabetes, lupus

what patient population must the nurse carefully monitor while administering furosemide?

children

what are the adverse effects of furosemide?

-fluid and electrolyte imbalances:

Na decreases

Ca decreases

K decreases

Cl decreases

BG increases

uric acid increases

-irreversible ototoxicity

what happens if furosemide is not pushed slowly?

irreversible ototoxicity

what are the drug interactions of furosemide?

oral hypoglycemics, warfarin; anticoagulant effect increases, aminoglycosides; risk for ototoxicity and nephrotoxicity, NSAIDs; decrease effect of the diuretic because it inhibits prostaglandins, digoxin; causes increased risk of hypokalemia

what are nursing implications for furosemide?

give loading dose then titrate infusion, monitor labs, may need supplemental potassium (20 milliequivalents)

what are other medications are also known as loop diuretics?

bumetanide, torsemide

what is the prototype for potassium sparing diuretics/aldosterone antagonists?

spironolactone (usually used in combination with another drug, UNLESS it's used for something other than HTN)

what is the mechanism of action for spironolactone?

acts at the distal tubule, blocks effects of aldosterone which promotes retention of K/Mg

what is spironolactone used for?

heart failure, ascites, hypokalemia, HTN, hyperaldosteronism, acne

what is spironolactone contraindicated with?

hyperkalemia; bc it promotes retention of potassium, renal disease, pregnancy

what is the BLACK BOX WARNING for spironolactone?

elevated K levels

what are the adverse effects of spironolactone?

deepening of voice (females), gynecomastia, menstrual irregularities, testicular atrophy, GI bleeding, electrolyte imbalances

what are the drug interactions of spironolactone?

ACE and ARBs also have a risk for hyperkalemia, salt substitutes bc they take the sodium out and the potassium in, BBs increase risk of hyperglycemia and increases triglycerides, digoxin lithium both increase risk for toxicity

what are the therapeutic effects of spironolactone?

blood pressure within normal limits, decreased acne

what are the nursing implications for spironolactone?

takes several days for full effects

what patient education is necessary for spironolactone?

avoid K rich foods like bananas, avocado, and broccoli, medication may take up to 6 weeks for full BP control, educate on adverse effects

what are commonalities for hypertension medications?

most are taken PO

HTN is related to kidney issues

CTX in conditions that may be exacerbated by decreased BP such like CAD or HF, look for history of cerebral insufficiency

AE: decreased BP, orthostatic hypotension (safety), labs (electrolytes)

avoid taking with grapefruit juice

avoid caffeine/nicotine/ OTC cold medications/ alcohol

caution with hot showers and strenuous exercise

should be taken EVERY DAY, do not stop abruptly

DI: if taken with other BP meds, BP may decrease

why do patients need to avoid grapefruit juice when taking hypertension medications?

it changes the acid in your gut which changes the absorption of the medication

why do patients need to avoid caffeine, nicotine, OTC medications, and alcohol when taking hypertension medications?

all promote vasoconstriction

what is the prototype of alpha-specific adrenergic agonists?

clonidine

what is the only cold medication available that is safe to use with blood pressure medications?

coricidin

what is the mechanism of action for clonidine?

arterial vasodilation and inhibits SNS

what is clonidine used for?

BP control and narcotic withdrawal

what route is clonidine administered?

transdermal/oral

what is clonidine contraindicated with?

narrow-angle glaucoma

what is clonidine cautioned with?

pregnancy, thyrotoxicosis, diabetes

what pregnancy category is clonidine?

C

how often does a clonidine patch need to be changed?

every 7 days

what are the adverse effects of clonidine?

CNS effects: related to SNS, strange dreams, sedation, anxiety; cardiac arrhythmias, ECG changes; changes in sexual function

what are the drug interactions of clonidine?

BBs increase BP, TCAs decrease effectiveness, adrenergic antagonists block what the agonist is trying to do

what are the nursing implications for clonidine?

must be tapered, SEVERE rebound HTN and tachycardia

what is the prototype for nonselective beta-adrenergic blocking agents?

propanolol

what is the mechanism of action for propanolol?

blocks beta-adrenergic receptors in the SNS

what are the off label uses of propanolol?

migraines, anxiety

what is propanolol contraindicated in?

bradycardia, heart block, bronchospasms, COPD, acute asthma, pregnancy (decreased BG, neonatal apnea, neonatal bradycardia, and neonatal hypoglycemia)

what is propanolol cautioned with?

diabetes/hypoglycemia; BBs block the SNS so patients will be hypoglycemic and not know

what are the adverse effects of propanolol?

CNS effects: depression, headache, fatigue, lethargy (especially elderly)

CV effects: decreased HR, decreased BP, decreased oxygen demand

pulmonary effects: bronchospasm

sexual dysfunction

what are the drug interactions of propanolol?

clonidine makes BP increase, NSAIDs decrease effectiveness, insulin/diabetic meds watch for hypoglycemia

what are the nursing implications of propanolol?

check pulse prior to administration because the BB will decrease HR, food increases bioavailability

what is the prototype of beta1-selective adrenergic blocking agents?

atenolol

what does beta 1 effect?

the heart

what does beta 2 effect?

the lungs

since atenolol only blocks beta 1 receptors what does it NOT effect?

the lungs

what is the mechanism of action for atenolol?

block beta 1 receptors

what are the contraindications of atenolol?

bradycardia, heart block, cardiogenic shock, HF, hypotension

what is atenolol cautioned with?

diabetes, thyroid disorders, COPD, pregnancy, lactation

what are the adverse effects of atenolol?

bradycardia, CNS effects: depression, CV effects: low HR, decreased BP, decreased sexual function

what are the drug interactions of atenolol?

NSAIDs decrease effectiveness, rifampin, barbiturates, clonidine all decrease effectiveness, vasoconstrictors

what are the nursing implications of atenolol?

must be tapered

what is the prototype for angiotensin-converting enzyme (ACE) inhibitors?

captopril

what is the mechanism of action for captopril?

interrupts the RAAS system, prevents conversion of angiotensin I into angiotensin II

what is the use of captopril?

blood pressure and heart failure management, renal protection for diabetes

what route is captopril administered?

oral

what does captopril reduce that helps patients with diabetes?

proetinuria

what is captopril cautioned in?

pregnancy and heart failure

what pregnancy category is captopril?

D