Hypertension Flashcards
(45 cards)
Diagnosis of hypertension
- Two or more measurements of blood pressure with diastolic pressure > 90 mmHg
- Systolic pressure > 140 mmHg
- Pulse pressure >65 mmHg
- > 50 yo, SBP >140 mmHg
Essential or primary hypertension
85-90% of cases, no identifiable cause, increased peripheral vascular resistance; normal cardiac output
Blood pressure =
CO X PVR
Diuresis
increase in urine volume
Natriuresis
increase in renal sodium excretion
why do many diuretics cause K+ loss (hypokalemia)?
sodium reabsorption triggers K+ secretion into the urine
Diuretics that act in the proximal tubule
carbonic anhydrase inhibitors
why are carbonic anhydrase inhibitors not very efficacious?
they work so early on in the nephron (not a mainstay treatment for hypertension)
Effects of long-term administration of diuretics on total peripheral resistance
decreased
Effects of long-term administration of diuretics on plasma volume
decreased or unchanged
Effects of long-term administration of diuretics on plasma renin activity
increased (works against you)
Diuretics that act in the loop of henle
loop diuretics
Name some loop diuretics
furosemide
bumetanide
ethacrynic acid
What do loop diuretics inhibit
inhibits the Na+/K+/2Cl- cotransporter in the thick ascending limb
Clinical uses of loop diuretics in cardiovascular disease
edematous conditions
acute pulmonary edema
Toxicities of loop diuretics
dehydration, hypokalemic metabolic alkalosis, ototoxicity, hyperuricemia, hypomagnesemia
More effective antihypertensive than loop diuretics in patients with normal renal function
thiazides
Diuretics that act in the distal convoluted tubule
thiazides
Name some thiazide diuretics
chlorthiazide, hydrochlorothiazide, trichlormethiazide, methyclothiazide, polythiazide, cyclothiazide
Name some thiazide-like diuretics
chlorthalidone, indapamide, metolazone
What is the difference between thiazide and thiazide-like diuretics
they are structurally unique but target the same Na+/Cl- transporter
Thiazides enhance the reabsorption of what
enhance Ca2+ reabsorption in the kidney
What do thiazides inhibit
inhibit NaCl reabsorption in the distal convoluted tubule
What might thiazides open that leads to vasodilation
may open Ca2+ -activated K+ channels leading to vasodilation