Hypertension Flashcards
Hypertension
Flow increases leading to pressure increase. Flow can be raised in two ways, such as fluid regulation by kidneys and higher sodium concentration in blood. Resistance increases leading to pressure increase. Resistance can increase through narrow lumen of vessels (vasoconstriction) or widening of the vessels(vasodilation) and stiffening off vessels can also increase resistance(atherosclerosis)
Stages of hypertension
Pre-hypertension(120-140 and 80-90)
Hypertension stage one (140-160, 90- 100)
Hypertension stage two (more than or equal to 160 and more than or equal to 100)
Isolated systolic, hypertension(systolic > 140, diastolic< 90, more common in elderly, cardiovascular complications)
Isolated, diastolic hypertension (Systolic < 140, diastolic> 90, more common and younger obese individuals)
Hypertension types and causes
Primary-: can be caused by indirect(smoking, obesity, hyperlipidemia, diabetes), more prevalent, develops gradually overtime and has no known cause, but are linked mostly to the risk factors (age, smoking, alcohol, consumption, obesity, no physical activity, poor diet(high salt), genetics)
Secondary can be caused by direct (kidney disease, aortic coarctation(pinched aorta)), less prevalent, causes are known, occurs due to other disease diseases(renal disease disease(PKD, glomerular disease, renovascular hypertension) , Cushing syndrome, primary aldosteronism, Pheochromocytoma, sleep apnea, obesity, brain tumor/encephalitis).
Hypertension effects on vessels
Arteries can become stiff(atherosclerosis, arteriosclerosis) ,vessel walls start weakening(aneurysm), kidney damage, retinopathy (eye damage), organ damage
Under normal circumstance, endothelium in blood vessels makes blood flow, relaxed, and resist clots in blood, but under high blood pressure, the endothelium gets microscopic tears, when the tears heal, they turn into scar tissues, which becomes site of plaque deposits leading to atherosclerosis. High blood pressure can also cause a bulging of very weak endothelium area, causing aneurysm.
Hypertension effect on heart
(The difference of arterial and venal pressure ) delta P = Q(flow) x R(resistance) , pressure goes up if flow or resistance or both go up. Pressure increase leads to heart to pump harder, build more muscle.( example left ventricular hypertrophy - risk of MI due to lack of perfusion to increased muscle mass), left heart failure(occurs if heart doesn’t build more muscle to provide for the body)
Complications of hypertension
Hypertensive retinopathy(vision issue because retina won’t receive oxygen due to damaged and weekend blood vessels) , stroke, heart failure(left ventricular hypertrophy), coronary artery disease, peripheral artery disease(arthrosclerosis elsewhere in body leads to neurosis, scar tissue).
Hypertensive crisis
Two categories: hypertensive urgency(above 180 and 110), doesn’t affect any target organs, symptoms: anxiety, headache, nosebleed, shortness of breath, management-oral medication, outpatient clinic.
Hypertensive emergency: ( above 180 and 120) , affect target organs, symptoms: chest pain, shortness of breath, back pain, numbness/weakness, vision, change, and difficulty speaking, can also cause encephalopathy(high blood pressure causes cerebral arterioles loose capacity to balance pressure in cerebral capillary beds leading to fluid or blood leaks out in cerebral space, causing edema and increased pressure in skull, can result in brain dysfunction), management vasodilator, calcium channel blockers, beta blockers through IV, intensive care unit.
Diagnosis of hypertension
Sphygmomanometer (blood pressure cuff), blood test-detect or damage, cause of secondary hypertension, blood urea nitrogen(BUN) levels and creatinine levels (together tell about kidney function), glucocorticoids level can indicate Cushing syndrome, blood glucose level, indicate diabetes, lipid profile, EKG: tall R waves(left ventricular hypertrophy), chest x-ray: to confirm left ventricular hypertrophy.
Treatment of hypertension
> 60 years-< 150 and< 90-(guidelines)- dietary changes: whole grains, fruits, vegetables, low salt(lifestyle changes)
< 60 years-< 140 and< 90(guidelines)- lower alcohol consumption(lifestyle changes)
18 years-< 140 and< 90(guidelines) include physical activity of at least 30 minutes(lifestyle changes).
Without CKD, diabetes :
First line treatment: Thiazide diuretics(eliminate salt and water to reduce fluid/flow), calcium channel blockers(block, calcium from entering smooth muscles of arterial walls, resulting in less contractions and relaxing vessels), ACE inhibitors(prevent renin angiotensin aldosterone system leading to block formation of angiotensin II (vasoconstrictor) -> widens the blood vessel-> reduces resistance, prevent production of aldosterone-> prevent retention of fluid-> reduce blood pressure), angiotensin II receptor blockers(blocks receptors that respond to angiotensinII)
Second line treatment: aldosterone receptor blockers(block receptors that respond to aldosterone), renin inhibitors ( inhibit renin -> no conversion of angiotensinogen to angiotensinI -> prevent formation of angiotensinII and aldosterone), alpha - adrenergic blockers( blocks receptors that are on smooth muscles of vessels-> vessels widen-> reduces resistance), central adrenergic inhibitors(prevents brain from sending signals to sympathetic nervous system system-> avoid fast, heart rate and vasoconstriction)
Four ways to manage hypertension
Dietary changes, exercise(aerobic)
