Hypertension (General) Flashcards
How is arterial pressure calculated
Determined by Cardiac Output and Peripheral Resistance
Pressure = Flow x Resistance
Essential Hypertension
No obvious cause
- Most common
- Genetic / Environmental contributes
Secondary Hypertension
Identifiable and correctable cause of hypertension
Much less common
What organ regulates blood pressure
Kidneys
Persistently High BP can cause?
Left Ventricular Hypertrophy (Gets bigger)
Remodeling of resistance arterioles
Predisposition to atherosclerosis
Increase risk of coronary thrombosis, stroke, renal failure
Antihypertensive Treatment starts with what?
RAS Inhibitor (Young / White Person)
Thiazide Diuretic / Ca2+ Inhibitor (Older / African Person)
If Antihypertensive Treatment does not help meet target BP what should be done
Add another class of drug, do not increase dose
Captopril Mechanism of Action
Inhibits ACE, preventing ANG II generation
–> Lowers BP
Captopril Adverse Effects
Hypotension
Cough
Taste Disturbance
Do not take if pregnant
Valsartan Mechanism of Action
Inhibits AT1-Receptors on Vascular Smooth Muscle Cells
–> Prevents action of Ang II
Valsartan Adverse Effects
Hypotension
Reversible Renal Impairment
Do not take if pregnant
Bendroflumethiazide Mechanism of Action
Bind and inhibit distal tubule Na+/Cl- cotransporter
- Decreases reabsorption of Sodium and Chloride
- Increased excretion of sodium, chloride, and water –> Urinate a lot
–> Decrease Blood Volume –> Decrease BP
Dihydropyridine Class
L-Type Voltage Gated Channel Antagonists
Mainly effect selective smooth muscle cells, treat hypertension
Dihydropyridine Mechanism of Action
Reduces Ca2+ entry intro SMC
Causes generalized arterial/arteriole dilation
–> Reduces BP
Dihydropyridine Adverse Side Effects
Flushing
Headache
Ankle Swelling
Prazosin Mechanism of Action
Blocks NE action on vascular smooth muscle cell
- Vasodilation and Fall in Arterial Pressure
–> Reduce BP
Prazosin Adverse Side Effect
Postural Hypotension
Stress Incontinence (Urinate Involuntary)
Impotence
Beta-Adrenoceptor Antagonists Mechanism of Action
Reduces Cardiac Output
Reduce Renin Release from Kidney
Reduce Sympathetic Activity Centrally
–> Reduction in BP takes a few days
Beta-Adrenoceptor Antagonists Adverse Effects
Bronchoconstriction
Cold Extremities
Fatigue
Cardiac Depression
Nitroprusside
- Treats what?
- How is it used?
Treats hypertensive emergencies
- Short Half-Life
- Requires continuous infusion and BP monitoring
- Very Powerful Vasodilator
Nitroprusside Mechanism of Action
NO Donor
- Stimulates cGMP signalling
Acts on both arterial and venous smooth muscles
Nitroprusside Adverse Effects
Generates cyanide
Weakness
Nausea
Inhibition of Thyroid Function
Only use short term (72 hours max)
