Test 1: Wk2: Vasodialators - Salisbury Flashcards
BP =
TPR x CO
Arteriodilation ➡⬇TPR
Venodialation ➡⬇CO
both lead to ⬇BP
Vasodilators compensatory mechanisms
⬆HR and ⬆fluid retention
Ca channel blockers (2)
Dihydropyridines and non
Dihydropyridines (1)
amlodipine
non-Dihydropyridines (2)
verapamil and Diltiazem
K channel opener (1)
Minoxidil
Dopamine D1 Receptor Antagonist (1)
Fenoldopam
Guanylate Cyclase Activators (5)
Nitroprusside Nitroglycerine Isosorbide Dinitrate Isosorbide Mononitrate Nitric Oxide
Phosphodiesterase inhibitors (2)
Sildenafil and Tadalafil
Ca Channel Blocker suffix
-dipine
All Ca channel blockers share what mechanisms
⬇Ca influx through voltage gated L type Ca Channels
Ca Channel Blockers targets (2)
blood vessels ion arterial system
heart
Vascular effects of Ca Channel Blockers
arteriodilation
⬇TPR➡⬇BP
are dihydropyridines stronger than non
yes, much stronger
Ca Channel Blockers Cardiac Effects
inhibit L-type Ca channels
Ca Channel Blockers inhibit what at the SA and AV nodes
phase 0 depol
Ca Channel Blockers inhibit what in cardiomyocytes
phase 2 action potential
Inhibition of L-type Ca channels leads to what 3 cardiac effects
⬇firing rate of SA node ➡⬇HR
⬇conduction velocity in AV node➡ block
⬇contractility of A and V muscles
Verapamil Diltiazem and Dihydropyridines cardiac effects
see chart
Ca Channel Blockers metabolized by
liver - hepatic metabolism
Ca Channel Blockers are effective through what administration
orally
Ca Channel Blockers uses
angina
Tx of angina
⬆ Coronary blood flow
⬇ MVO2 demand
how do Ca Channel Blockers ⬇ MVO2 demand
2 ways
⬇ afterload (all)
⬇ CO (verapamil and diltiazam)
what drug treats Supraventricular Tachyarrhythmias
verapmil - Ca Channel Blockers
how does verapamil treat Supraventricular Tachyarrhythmias (3 ways)
⬇ AV nodal conduction
control V and A flutter and A fib
⬇ PSVT
Ca Channel Blockers are used for — by — and —
hypertension
⬇ TPR
⬇ CO
which Ca Channel Blockers decrease CO
verapamil and diltiazem
Ca Channel Blockers adverse effects
see chart
Ca Channel Blockers contraindications (3)
avoid short term acting agents (Nifefipine)
Severe hepatic dysfunction
LV Dysfuntion
Short acting agents given with Ca Channel Blockers and increase
mortality and risk if MI
Ca Channel Blockers precautions (3)
Hypotension (all)
AV block (verapamil and diltiazem)
Sick sinus syndrome (verapamil and diltiazem)
Ca Channel Blockers drug interactions (4)
CYP3A4 inhibitors/ inducers
B blockers (verapamil diltiazem)
Digoxin (verapamil)
Antiarrhythmic drugs
Minoxidil is a
K channel opener
Minoxidil increases — efflux from vascular SM cells ➡ —➡ — ⬇ — ➡ ⬇—
Minoxidil increases K+ efflux from vascular SM cells ➡ hyperpol ➡ relaxation ⬇ TPR ➡ ⬇ BP
Minoxidil compensatory mechanism
increase HR CO and fluid accumulation
Minoxidil is a potent —
vasodilatior
Minoxidil therapeutic uses (2)
refractory/malignant hypertension
alopecia
Minoxidil adverse effects (4)
fluid retention
tachycardia
pericardial effusion/ cardiac tamponade
hypertrichosis
Guanylyl Cyclase Activators mechanisms
activate GC
⬆ cGMP formation
⬆cGMP ➡ vasodilation
Nitroprusside effects on arteriodilation and venodilation
they are balanced
Nitroprusside Arteridilation ➡
⬇TPR➡⬇BP
Nitroprusside venodilation ➡
⬇Preload➡ ⬇CO ➡⬇BP
⬇BP ➡ Reflex ➡
⬆HR
Nitroprusside overall effects
⬇TPR
⬇BP
⬇CO
⬆HR
Nitroprusside t1/2 and onset
2min
immediate
Nitroprusside administration
IV only
— sensitivity with Nitroprusside
light
Nitroprusside therapeutic uses (3)
hypertensive emergencies
CHF
MI
Nitroprusside acute adverse effects
hypotension
Nitroprusside chronic effects
CN- toxicity
what can be given with Nitroprusside to reduce CN- toxicity
Thiosulfate
Organic Nitrates (3)
Nitroglycerin
Longer acting
ISDN
ISMN
Effects of Organic Nitrates are
dose related
Organic Nitrates Low Dose
venodilation
see slide for more info
Organic Nitrates High Dose
Venodilation
Arteriodilation
Reflex ⬆HR
what Organic Nitrates have extensive first pass HM
nitroglycerin and ISDN
what enzyme denitrations Organic Nitratesin HM
Glutathione-organic nitrate reductase
what Organic Nitrates experience Vascular Metabolism
nitroglycerin
how is nitroglycerin metabolized in vasulature
nitroglycerine ➡ ALDH2 ➡ NO
Organic Nitrates tolerance
tx for >24 hrs
nitrate free period of 8-12 hrs
nitroglycerin ointment dosing interval
3-4x day remove for 12 hr
nitroglycerin patch dosing
1x daily remove for 12 hr
ISDN oral sustained relase dosing
1-2x daily, 14hr tablet free interval
ISMN
1x daily
Organic Nitrates therapeutic uses (3)
angina
CHF
Acute MI
Organic Nitrates adverse effects (2)
excessive hypotension
tolerance
excessive hypotension effects
headache
tachycardia
orthostatic hypotension
angina
Organic Nitrates with PDE5 inhibitors will result in
extreme hypotension
Nitric oxide administration and t1/2
inhalation
very short
nitrate and nitrite excreted in
urine
Nitric oxide therapeutic uses
reverse hypoxic respiratory failure in neonates with pulmonary hypertension
Nitric oxide adverse effects (2)
pulmonary edema
hypoxemia
Hydralazine is a strong
arterial dialator
Hydralazine therapeutic uses
CHF
Hypertension
Hydralazine metabolism
hepatic and renal
Hydralazine adverse effects (5)
fluid retention tachycardia headache hypotension drug induced lupus-like syndrome
antinuclear antibody positve is caused by what drug
hydralazine
drug induced lupus-like syndrome risk factors
slow acetylates and female
Fenoldopam is a
peripheral dopamine D1 receptor agonist
Fenoldopam induces
systemic and renal arterial vasodilation
Fenoldopam adminstration
IV - rapid acting 15-20 min
lasts 1-4 hrs
Fenoldopam uses
hypertensive emergency
Fenoldopam adverse effects (3)
hypersensitivity to sodium metabisulfate
tachycardia
hypotension
PDE inhibitors (3)
sildenafil, tadalafil, verdenafil
PDE Inhibitors inhibit — resulting in —
PDE type 5 resulting in ⬆ NO cGMP
PDE Inhibitors relax SM in — and — resulting in — and —-
corpus cavernosum and lower urinary tract
erection and urination
sildenafil, verdenafil, tadalafil time to peak conc.
1
1
1.5 hrs
sildenafil, verdenafil, tadalafil t1/2
3-4
4-5
18
sildenafil, verdenafil, tadalafil uses
erectile dysfunction
BPG - tadalafil
sildenafil, verdenafil, tadalafil kinetics
orally
HM metabolized
sildenafil, verdenafil, tadalafil adverse effects
hypotension
sildenafil, verdenafil, tadalafil contraindications (4)
organic nitrates
a-blockers
CYP3A4 drugs
hepatic dysfunction