Final Quiz Material Flashcards
Equation for BP
BP = CO x SVR
Equation for CO
CO = SV x HR
3 things that contribute to stroke volume
- preload
- afterload
- contractility
2 centrally acting antihypertensive agents
1) a-Methyldopa
2) Clonidine/Dex
Clonidine shares a structure-activity relationship with which catecholamine
Norepi
MOA of Methyldopa and Clonidine
decreases SVR and CO 2* to decreased sympathetic outflow
SE of Methyldopa
- CNS effects
- hyperprolactinemia
- Coombs test w/ or w/o hemolytic anemia
Which centrally acting antihypertensive can be given transdermally? Why?
Clonidine - highly lipid soluble
Problems with centrally acting antihypertensives:
- sedation
- orthostatic hypotension
- endocrine problems
- Na+ and H2O retention
- rebound HTN with abrupt withdrawal
2 peripherally acting adrenergic agents
- Guanethidine
- Reserpine
MOA of peripheral acting adrenergic agents in genreal
- catecholamine depleters
MOA of Guanethidine
- replacement and gradual depletion of NE
- transported across symp membrane by same mech as NE
similar to Guanadrel
SE of Guanethidine
- profound postural hypotension
- drug interactions
MOA of Reserpine
- blocks ability of adrenergic vesicles to take up and store NE, DA, and serotonin
- results in central and peripheral depletion
SE of Reserpine
- depression
- EPS
Problems associated with blocking NE release and storage
- orthostatic hypotension
- nasal stuffiness
- impairment of ejaculation
- increased GI activity
- EPS
2 mixed beta antagonists and their receptor selectivity
- Labetalol and Carvedilol
B1=B2>A1>A2
Problems with B-adrenergic receptor blockers
- HF in pts with cardiac disease
- increased airway resistance
- fatigue
- depression
- rebound HTN
- masking hypoglycemia
Prazosin, Terazosin, Doxazosin receptor selectivity
A1»»A2
A1-selective blockers
Phenoxybenzamine receptor selectivity
A1>A1
irreversible
Phentolamine receptor selectivity
A1=A2
Problems with A-adrenergic receptor blockers
- orthostatic hypotension
- tachycardia w/ non-selectives
- nasal stuffiness
- ejaculation impairment
- Na+ and H2O retention (blocked renin release)
List 3 ACE inhibitors
- Captopril
- Enalapril
- Lisinopril
Most favored ACE inhibitor and why
Lisinopril - pharmacokinetics means it is dosed once daily
Mechanism for why some patients get a cough with ACE inhibitors:
accumulation of bradykinin
MOA of ACE inhibitors
- decreased conversion of AT1 to ATII
- decreased aldosterone
SE of ACE inhibitors
- pregnancy category D
- hyperkalemia
- cough
- caution with renal patients (accumulation, renal artery stenosis, GFR alteration)
SE of ACE inhibitors are worsened with what condition
hypovolemia
MOA of ARBs
- block ATII from binding to ATI receptors
SE of ARBs
- pregnancy category D
- hyperkalemia
- renal effects
Antihypertensive class that can increase SVR
B-blockers
Most reabsorption of water and ions in the renal system occurs in the _______
proximal tubule
Class of diuretics that are most effective at excreting Na+
loop diuretics > metolazone = thiazides > K+ sparing
Class of diuretics working on the proximal tubule
carbonic anhydrase inhibitors
MOA of Acetazolamide
- carbonic anhydrase inhibitor
- causes excretion of bicarb
Uses for carbonic anhydrase inhibitors
- metabolic alkalosis
- urinary alkalization
- glaucoma
- altitude sickness
Problems with carbonic anhydrase inhibitors
- hyperchloremic metabolic acidosis
- ammonia toxicity
- sulfa allergy
Drugs used in open-angle glaucoma therapy:
- pilocarpine
- carbachol
- physostigmine
- echothiophate
- timolol
- acetazolamide
Diuretics that work on the ascending loop of Henle are most effective at doing what?
moving fluid
List 3 loop duretics
- furosemide
- bumetanide
- ethacrynic acid
MOA of Furosemide
- works on inhibition of Na/K/Cl co-transport in in the ascending LoH
- direct vasodilating effect
Uses of Furosemide
- edema
- CHF
- HTN
- hypercalcemia
Problems with Furosemide
- ototoxicity
- hypokalemia/mag/natremia
- hypovolemia
- hyperuricemia
- interstitial nephritis
- hypokalemic metabolic acidosis
- sulfa allergies?
MOA of Ethacrynic acid
- works on inhibition of Na/K/Cl co-transport in in the ascending LoH
NOT a sulfonamide
Uses of Ethacrynic acid
diuretic for patients with sulfa allergy (cannot get Lasix)
Problems with Ethacrynic acid
- ototoxicity
- hypokalemia/mag/natremia
- hypovolemia
- interstitial nephritis
- hypokalemic metabolic acidosis
NO hyperuricemia, NO sulfa allergy
MOA of hydrochlorothiazide
- inhibits NaCl reabsorption in the early distal tubule
- direct vascular effects
Uses of HCTZ
- HTN
- CHF
- nephrogenic DI
- renal calcium stone formation
- osteoporosis
Problems with HCTZ
- hypokalemic metabolic alkalosis
- hyponatremia
- hyperglycemia
- hyperlipidemia
- hyperuricemia
- hypercalcemia
Mechanism for how thiazide diuretics cause hypokalemia
inhibition of the NaCl pump dumps extra Na+ into the lumen; Na+ is later exchanged for K+, so the excess Na+ causes excess K+ to be kicked out
Where do potassium sparing diuretics work?
collecting tubule
MOA of Spironolactone
competitive aldosterone antagonist
(4-ring structure)
MOA of Triamterene and Amiloride
block Na+ channels in collecting tubule
List 3 potassium sparing diuretics
- Spironolactone
- Triamterene
- Amiloride
Uses for potassium sparing diuretics
- hyperaldosteronism (cirrhosis & ascites)
- CHF
- often added to non-K-sparing agents
Problems with potassium sparing diuretics
- hyperkalemia
- endocrine effects (Spironolactone)
Where do osmotic diuretics work?
- proximal convoluted tubule
- descending LoH
- collecting duct
attract water in areas of tubule that are freely permeable to H2O
Mannitol is a…..
osmotic diuretic
Uses for mannitol
- increase urine volume
- prevent anuria in hemolysis or rhabdo
- reduce ICP or IOP
Problems with osmotic diuretics
- extracellular volume expansion
- dehydration
- hypernatremia
List 2 ADH antagonists
- Lithium
- Demeclocycline
MOA of ADH antagonists
inhibit the effects of ADH on the collecting tubule (thought to decrease cAMP response to ADH)
Uses of ADH antagonists
SIADH when water restriction failed
Problems with ADH antagonists
- nephrogenic DI
- hypernatremia
- acute renal failure
Which diuretics have the greatest impact on HCO3-
carbonic anhydrase inhibitors
BB can interact with which class of diuretics? to create what problem?
- interact with thiazides
- problem: increase in blood glucose, urates, lipids
Digitalis glycosides can interact with which class of diuretics? to create what problem?
- interact with thiazides and loop diuretics
- problem: hypokalemia –> dig toxicity
ACE inhibitors can interact with which class of diuretics? to create what problem?
- interact with K-sparing
- problem: hyperkalemia, cardiac effects
Aminoglycosides can interact with which class of diuretics? to create what problem?
- interact with loop diuretics
- problem: ototoxicity, nephrotoxicity
Adrenal steroids can interact with which class of diuretics? to create what problem?
- interact with thiazides and loop diuretics
- problem: enhanced hypokalemia
Chlorpropamide can interact with which class of diuretics? to create what problem?
- interact with thiazides
- problem: hyponatremia
Formula and normal value for cardiac output
CO = HR x SV
4-8L/min
Formula and normal value for cardiac index
CI = CO / BSA
2.5-4 L/min/m2
Normal value for MAP
70-90 mmHg
Formula and normal value for coronary perfusion pressure
CPP = DBP - PAWP
60-70 mmHg
Formula and normal value for rate pressure product
RPP = HR x SBP
<12,000
MOA of nitrates (in general)
- nitric oxide activates guanylyl cyclase
- increased cGMP
- sarcoplasmic reticulum sequesters Ca2+
- decreased smooth muscle contraction
- vasodilation
MOA of Nitroglycerin
increased NO production –> increased cGMP
Effects of Nitroglycerin
- primarily preload reduction
- afterload effects @ higher doses
Advantages of Nitroglycerin
- very titratable
- more specific for preload
Disadvantages of Nitroglycerin
- HA
- nitrate tolerance
- withdrawal
- special tubing & glass vials d/t diffuses into plastic
MOA of Isosorbide Dinitrate
- increased NO production –> increased cGMP