Hypertension

Hypertension


Hypertension

-For adults over 18 defined as SBP > 140 mm Hg and DBP > 90 mmHg
-Diagnosis requires elevated reading on 3 separate visits
-Essential HTN known as Primary Hypertension
-Defined as hypertension with no identifiable cause

-Secondary Hypertension
-Caused by an underlying problem
-Renal Parenchymal Disease
-Renal Artery Stenosis
-Aortic Coarctation
-Carcinoid Syndrome
-Pregnancy
-Hypothyroid or Hyperthyroidism
-Hyperparathyroidism
-Cushing Syndrome
-Pheochromocytoma
-Hormone Replacement Therapy
-Brain Tumor
-Pain, stress, and anxiety
-Sleep Apnea
-Porphyria
-Lead Poisoning
-Hypoglycemia
-Alcohol withdrawal
-NSAIDS
-Alcohol
-Ephedrine
-MAO inhibitors
-Corticosteroids


-HTN Treatment

-Lifestyle Modifications

-JNC Guidelines

-Stage I HTN (SBP 140-159 or DBP 90-99) Thiazide Diuretics first
-May also consider ACE inhibitors, ARB’s, Beta Blockers or Calcium Channel Blockers
-Stage 2 HTN (SBP >160 mmHg or DBP >100 mmHg)
-2 Drug Combination for most
-Combination with ACE inhibitor, ARB, Beta Blocker or Calcium Channel Blockers


-Accelerated HTN
-Also known as hypertensive urgency
-SBP >200 mmHg and DBP >120 mmHg.
-May need admitted


-Hypertensive Emergency
-Also known as malignant hypertension
-When patients have elevated blood pressure (>200 SBP and DBP > 120 mmHg) and have evidence of end organ damage
-May reverse when BP is lowered


-HTN Treatment

-Diuretics
-Loop Diuretics (High Ceiling)
-Thiazide Diuretics
-Potassium Sparring Diuretics
-Loop Diuretics
-Furosemide and Bumex
-Mechanism-works on the ascending loop of Henle to block reabsorption of sodium and chloride
-This then prevents passive reabsorption of water
-Reserved for when there is a need for fluid removal
-Adverse Effects-hyponatremia, dehydration, hypotension, hypokalemia, ototoxicity, hyperglycemia, and elevated uric acid levels

-Thiazide Diuretics
-Hydrochlorothiazide (Hctz)
-Mechanism-blocks the reabsorption of sodium and chloride in the early segment of the distal convoluted tubule
-This passively causes an increase of flow of water and increased urinary output
-Generally considered first line in essential hypertension
-Other indication is benign peripheral edema
-Adverse effects-low Na, Cl, and low K.  Also dehydration, hyperglycemia, and elevated uric acid levels

-Potassium Sparing Diuretics
-Spironolactone and Triamterene
-Mechanism-blocks the sodium potassium exchange in the distal nephron
-Indicated for hypertension or benign peripheral edema
-Adverse Effects-hyperkalemia, leg cramps, and dizziness
Caution when in use with ACE inhibitors

-Osmotic Diuretics
-Mannitol
-Mechanism-creates osmotic force within the lumen of the nephron
-Indications reduction of intracranial pressure (ICP), intraocular pressure, and prophylaxis of renal failure
-Adverse Effects
-Adverse Effects
-Headache
-nausea and vomiting
-fluid and electrolyte imbalances


-ACE Inhibitors

-Mechanism-blocks ACE which inhibits production of angiotensin II
-Prevents the breakdown of Bradykinnin a vasodilator.
-Elevates Prostaglandins  (vasodilator)

-Indications
-HTN
-Heart Failure
-Nephropathy

-Adverse Effects-dry cough (bradykinnin), hyperkalemia, first dose hypotension, renal failure, and angioedema

-Angioedema can be from C1 Esterase Deficiency

-Angiotensin Receptor Blockers (ARB's)
-Block Angiotensin II Receptor
-No elevated Bradykinnin Elevation
-Vasodilator

-Indications
-Hypertension
-Heart Failure
-Myocardial Infarction
-Renal Impairment
-Adverse Effects
-Dizziness
-No dry cough because of  no Bradykinnin elevation


-Calcium Channel Blockers
-Classifications
-Dihydropyridines (Nifedipine)
-Non Dihydropyridines
-Phenylalkamines (Verapamil)
-Benzothiazepines (Diltazem)

-Dihydropyridines-dilate arterioles. Nifedipine, Amlodipine, Nicardipine, and Felodipine
-Non Dihydropyridines- diltazem and verapmil block calcium channels in the heart and arterioles (slows heart and dilates arterioles)

-Adverse Effects-constipation, bradycardia, edema, AV Blocks
-Can also cause gingival hyperplasia
-Diltazem and Verapmil good for rate control with Atrial Fibrillation
-Verapmil used for Prinzmetal’s Angina


-Vasodilators
-Hydralazine-selectively dilates arterioles
-Indications-HTN, Hypertensive crisis, and Heart Failure
-Adverse effects-reflex tachycardia, increase in blood volume, and hypotension, and dizziness

-Nitroprusside-dilates the venous and arterial systems.
-Used for hypertensive urgency
-Metabolizes can accumulate and cause cyanide poisoning.
-Adverse effect-hypotension, cyanide poisoning and thiocyanate toxicity

-Nitroglycerin-mainly causes dilation of veins
-Used to treat angina, heart failure and myocardial infarction
-oral form is isosorbide

-Alpha Adrenergic Blocking Agents- (Prazosin)
-prevent stimulation of alpha adrenergic receptors on veins and arterioles
-Used in HTN, Peripheral Vascular Disease, and pheochromocytoma

-Centrally Acting Agents-(methyldopa and clonidine) inhibit outflow of impulses along sympathetic nerves
-Used for hypertension
-Can cause rebound hypertension if discontinued abruptly.

-Beta Blockers
-work by blocking primary Beta 1 receptors in the heart and slow heart rate (Propranol, Atenolol, Metoprolol)
-Indications-HTN, MI, CAD, CHF, Tachycardia, SVT, severe recurrent VT, migraines, and stage fright
-Adverse effects-AV block, bradycardia, bronchospasm, heart failure