Exam 3 Flashcards
Risk factors for Primary Hypertension aka Essential
Obesity Stress Smoking Age Diet Race
Define Secondary Hypertension
Has definitive cause like stenosis or renal artery, or pheochromocytoma
Complications of HTN
CAD Cardiac/Renal Failure Stroke TIA's MI
Centrally acting hypertensives action
Decrease sympathetic outflow to HRT which decrease HR which decreases myocardial contractility which decreases CO which decreases BP
Centrally acting hypertensives work on which receptor?
A2 receptors in the CNS
Alpha-adrenergic blockers action
Block A1 receptors which cause vasodilation which decreases peripheral resistance which decreases BP
Name an Alpha-adrenergic blocker
Prazosin (Minipress)
Beta-adrenergic Action
Blocks B1 receptors which decreases HR and myocardial contractility with decreases CO which decreases BP
Name Beta adrenergic drugs
Propranolol - B1 &B2 blocker Metoprolol - cardio selective B1 Atenolol - Cardio selective Labetolol - also blocks A receptors Cavedilol - also blocks A receptors
Ganglionic Blocker action
At high doses it blocks ganglia which block the sympathetic outflow to BV’s which decreases BP
Name a Ganglionic Blocker drug
Mecamylamine
Name Postganglionic adrenergic neuronal blockers
Reserpine
Guanethidine
Reserpine Action
Blocks the uptake of dopamine in the synaptic vesicles blocking the formation of norepinephrine (doesn’t work on adrenergic receptors)
Guanethidine Action
Inhibits release of NE
Types of Diuretics?
Thiazide Diuretics
Loop Diuretics
Potassium Sparing Diuretics
Example of Thiazide diuretics?
Hydrochlorothiazide
Example of Loop diuretic?
Furosemide
Example of Potassium Sparing diuretic?
Spironolactone
Structural unit of the kidney?
Nephron
Why are diuretics used?
Decrease blood volume which decreases BP
What’s the action of diuretics?
Blocks reabsorption of NA
Where on the nephron is 65% of Na reabsorbed?
Proximal Convulated Tubule (PCT)
Where on the nephron is 20% of Na reabsorbed?
Loop of Henle
Where on the nephron is 10% of Na reabsorbed?
DCT
Where on the nephron is 1-5% of Na reabsorbed?
Collecting Duct (Spironolactone)
Where on the nephron do Thiazide diuretics work?
DCT = Weak diuretic
Where on the nephron do Loop Diuretics work?
LOH (20%) greater diuresis
Indications of Thiazide Diuretics?
Mild to moderate HTN
MOA of Thiazide diuretics?
Block reabsorption of NA, Cl in the early segment of DCT which blocks reabsorption of H2O (where sodium goes water follow). Will only work with decent renal function
Adverse Effects of Thiazide Diuretics?
- HYPONATREMIA
- HYPOCHLOREMIA
- HYPOKALEMIA (^NA reabsorption at CD, aldosterone secreted, some NA reabsorbed in exchange for K secreted)
- HYPERGLYCEMIA ( inhibition of insulin releases, promotion of glycogenolysis, inhibition of glycogen genesis)
- HYPERURICEMIA (^ urine acid in the blood)
- ALTERATION OF LIPID PROFILE (LDL ^ - high cholesterol, HDL decreases)
Indications of Loop Diuretics?
Pulmonary edema
Edema associated with cardiac, renal or hepatic origin
Adverse effects of Loop Diuretics?
- HYPONATREMIA
- HYPOCHLOREMIA
- HYPOKALEMIA (^NA reabsorption at CD, aldosterone secreted, some NA reabsorbed in exchange for K secreted)
- HYPERGLYCEMIA ( inhibition of insulin releases, promotion of glycogenolysis, inhibition of glycogen genesis)
- HYPERURICEMIA (^ urine acid in the blood)
- ALTERATION OF LIPID PROFILE (LDL ^ - high cholesterol, HDL decreases)
- OTOTOXICITY (damage to ear)
Loop diuretics and other drug interactions?
Patients taking amino glycoside antibiotics (Gentamicin) cause ototoxicity
Potassium sparing diuretics indication?
To avoid side effects, use K sparing diuretics - acts at the level of the Collecting Ducts
Someone on Digoxin what should you give to maintain K levels elevated?
Spironolactone
Action of Spironolactone?
Blocks aldosterone (NA not reabsorbed, is eliminated with H2O, K is retained - K levels should be 3.5-5.5 meq/L)
Name Vasodilators used for HTN?
- Hydralazine
- Minoxidil
- Sodium Nitroprusside
- Calcium Channel Blockers
Hydralazine, Minoxidil MOA?
Hyperpolarize vascular smooth muscle by opening up K channels > away form threshold > no contraction of smooth muscle in the blood > vessels dilate (affects mainly the arteries)
Adverse effects of Hydralazine and Minoxidil?
[] Hydralazine - Lupus like reactions (butterfly rash)
[] Minoxidil - Pericardial effusion (fluid in the pericardium) leading to cardiac tamponade (pressure on the heart)
Indications for Sodium Nitroprusside?
Drug of choice for emergency HTN
Sodium Nitroprusside MOA?
- Increases levels of cGMP > dilates BV’s (both arteries and veins)
- When metabolized cyanide is released > can lead to cyanide poisoning (rhodanese reduces level of toxicity for cyanide poisoning > cyanide detoxification)
Name Calcium Channel Blockers Drugs used to treat HTN?
Verapamil (Calan)
Amlodipine (norvasc)
Nifedipine (Aldolat, Procardia)
Action of Verapamil?
- Dilates peripheral arteries to ↓ BP
- Dilates arteries going to myocardium (coronary vessels)
- Has a cardio suppressant effect → ↓HR, ↓AV nodal conductions, myocardial contraction (but body’s baroreceptors ↑ actions on the heart canceling the effects on the heart)
Adverse effects of Verapamil?
- Constipation
- Edema of ankles and feet
Indications for Verapamil?
- Used for angina pectoris, HTN, cardiac dysrhythmias
Nifedipine action?
- Acts like Verapamil, but it doesn’t suppress the heart
- If we get a baroreceptor reflex → reflex tachycardia (give ß blocker to prevent tachycardia)
Name ACE Inhibitors to treat HTN?
- Captopril (Capoten)
- Enalapril (Vasotec)
Antiotensin → Angiotensin II Mechanism?
Angiotensin converting enzyme (ACE) makes Angiotensin II from Angiotensin I
Systemic Vasoconstrictor that increases BP?
Angiotensin II
Stimulates aldosterone secretion and NA retention by kidneys. ( ↑ H2O reabsorption → ↑blood volume → ↑BP)
Angiotensin II
Stimulates ADH. (↑ H2O reabsorption → ↑blood volume → ↑BP)
Angiotensin II
When you give ACE inhibitors BP decreases because?
Angiotensin II is no longer produced?
What else does ACE work on?
Bradykinin
What’s Bradykinin?
A vessel dilator, won’t be broken down when given ACEi it decreases BP
What is ACE called when working on Bradykinin?
Kinase II
