UNIT 4 Hypertension Flashcards
(46 cards)
ThiaSystolic Blood Pressure
contraction phase; highest amount of pressure
Hypertension
increased pressure on arterial walls;
“silent killer”;
asymptomatic;
may lead to other complications: heart failure, cerebral hemorrhage - stroke, kidney failure, MI
Diastolic Pressure
relaxation phase; lowest amount of pressure
Normal Blood Pressure
Systolic: less than 120
Diastolic: less than 80
Two Types of Hypertension
Primary Hypertension/Essential Hypertension (most common)
Secondary Hypertension (a medical condition present)
Primary Hypertension/Essential Hypertension
most common;
cause is unknown;
risk factors: smoking, obesity, racial predisposition, family history, stress, sedentary lifestyle, high-fat diet
Seondary Hypertension
a medical condition present;
pregnancy, renal disease, drug-induces
Risk Factors for Hypertension
Stress, age: over 60, family history, gender: men and postmenopausal women, increased cholesterol, high sodium diet, sedentary lifestyles, smoking, diabetes
Baroreceptors
located in the internal walls of carotid arteries and the aortic arch and other vessels in the body sense the change in BP;
sensors that control BP
Blood Pressure Control
if BP decreases, baroreceptors sense the change; EPI and NE are released to constrict smooth muscle of the vessels; this increases BP
if BP increases, baroreceptors sense the change; vagus nerve is stimulated; HR, FOC, CO decrease; vasodilation occurs; this decreases BP
Renin-Angiotensin-Aldosterone System (RAAS)
maintains normal BP and blood volume
Angiotensin I is secreted by the kidney (is a vasoconstrictor; increases TPR and BP)
ACE is secreted by the liver
Angiotensin II is formed in the plasma; works on adrenal cortex and is a potent vasoconstrictor
Aldosterone is released by the adrenal cortex
Aldosterone works on the kidneys to conserve Na+ and H2O; this increases blood volume and BP
Angiotensin II stimulates the release of Antidiuretic hormone from the posterior lobe of the pituitary gland;
this stimulates the thirst center (higher fluid intake -> higher volume of blood)
this hormone also stimulates the kidney to pull water from the urine back into blood (higher blood volume); it is also a potent vasoconstrictor
Kidney
filter the blood, maintain water and electrolyte balance, maintains the acid-base balance, secretes urine, allows the blood to gain the necessary nutrients (water and electrolytes), is composed of nephrons
Nephron
a structure of the kidney;
consists of a glomerulus, a proximal collecting tubule, a loop of Henle, a distal convoluted tubule and a collecting duct
Rules with ions in kidneys
If Na+ goes out, so does H2O
If Na+ goes in, K+ comes out
If H+ goes in, Na+ goes out
If Cl- goes in, Na+ goes out
Urine Formation
Filtration - H2O, salts, sugars, acids, drugs, nitrogenous wastes leave the blood; large particles stay (proteins and blood cells)
Tubular Reabsorption - body retains H2O, salts, sugars
Tubular Secretion - substances from blood go back into the renal tubule (drugs, acids, nitrogenous wastes, salts and H2O) as wastes products to be excreted
Reabsorption
Glomerulus - filtration occurs
Tubular Reabsorption -
PCT & DCT - H+ is secreted; Na+ and H2O is reabsorbed
DCT - Aldosterone is secreted along with K+; Na+ and H2O are reabsorbed (increase in aldosterone may cause hyperkalemia)
Loop of Henle - CL- is reabsorbed along with Na+ and H2O
Collecting duct - ADH maintains the water balance, decrease in urine output, increase in blood volume
- No ADH: increase in urine output and decrease in blood volume
Tubular Secretion - occurs when ions from blood go into the tubules
Non-pharmacological Treatment of HTN
decrease sodium input, reduce fat intake, decrease stress, increase physical activity, rest, moderate alcohol intake, weight loss
Antihypertensive Pharmacological Treatment
Vasodilators, CCB, BB, diuretics, ACE inhibitors, ARB, renin inhibitors, combo therapy
Diuretics
USES: CHF, HTN, edema, anuria, renal disease
Types: Osmotic Diuretics, Thiazide/Thiazide-like Diuretics, Loop Diuretics (Organic Acid Diuretics)
Osmotic Diuretic
decreased ICP; pulls water from tissues (changes plasma osmolality)
mannitol (Osmitrol)
Thiazide/Thiazide-like Diuretics
do not spare K+;
block reabsorption of Na+, diuresis, Na+ and H2O loss
- sulfa derivative, if allergic to sulfonamides, these are contradicted
Thiazide Diuretic:
hydrochlorothiazide (HCTZ) (Hydrodiuril)
Thiazide-like Diuretic:
chlorthalidone (Hygroton)
indapamide (Lozol)
metolazone (Zaroxolyn)
Loop Diuretics (Organic Acid Diuretics)
do not spare K+ (secreted through urine)
USES: edema, HTN, pulmonary congestion, liver and kidney disease
MOA: inhibit Na+ and Cl- transport in Loop of Henle -> this increases Na+, Cl- and H2O secretion
DRUGS:
furosemide (Lasix)
torsemide (Demadex)
Potassium Sparing Diuretics (Aldosterone Receptor Antagonists)
control K+ depletion through urine
DRUGS:
amiloride (Midamor)
sprinolactane (Aldactone)
triamterene (Dyrenium)
(possible hyperkalemia and gynecomastia)
Diuretics (Common Side Effects)
Hypotension,
orthostatic hypotension,
reflex tachycardia,
thirsty/dry mouth,
nausea
