diuretics

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Pathophysiology of & rsquo; essential hypertension :

The average blood pressure is the product of cardiac output by systemic arterial resistance.

Cardiac output is, his, depending on product volume & rsquo; systolic ejection heart rate. L & rsquo; constant abnormality of & rsquo; blood pressure established is represented by & rsquo; increased systemic arterial resistance.

* Beta-blockers :

Mechanism & rsquo; action and physiological effects :

The d & rsquo mechanism; action of beta blockers n & rsquo; is not cleared, three main hypotheses are put forward for the & rsquo; action of beta-blockers :

  • decreased cardiac contractility.
  • decreasing renin release.
  • action on the nervous system.

molecules :

generations : atenolol, acebutolol, bisoprolol…

against indications :

Full Bav or degree unaided . asthma . Advanced arterial stage Raynaud's phenomenon.

preferential indications :

Myocardial infarction, angina, failure .troubles cardiac rhythm and pregnancy.

Avoid especially in combination with diuretics if metabolic sd.

Side effects :

Metabolic disorders bradycardia, Raynaud's phenomenon, incapacity

* Calcium channel blockers :

Mechanism & rsquo; Action :

Calcium channel blockers appear to act by inhibiting transmembrane calcium transfer. They thus reduce the rate of intracellular free Ca, which has the effect of reducing the muscle tone vascular smooth.

molecules :

Les dihydropyridines : exp amlodipine and non-dihydropyridine : exp diltiazem.

Indications preferentielles :

HVG, elderly, about black, pregnancy, angina, angor the Prinzmetal, pregnancy…

Side effects :

headaches, vasomotor crisis, tachycardia for HPD and conduction disorders for non-DHP, leg edema…

* THE IEC :

Mechanism & rsquo; Action :

Inhibit the secretion of & rsquo; converting enzyme.

preferential indications :

Diabetes ,metabolic sd , kidney damage, heart failure

molecules :

Captopril, ramipril….

Contraindication :

Pregnancy,bilateral stenosis of the renal arteries, association with ARB

Side effects :

cough…

* LES ARAII :

preferential indications :

Diabetes ,metabolic sd, kidney damage, heart failure

molecules :

LOSARTAN, IRBESARTAN ….

Contraindication :

Pregnancy,bilateral stenosis of the renal arteries, combination with ACE inhibitors. Side effects : well tolerated.

* THE diuretic :

INTRODUCTION :

  • INCREASING THE VOLUME OF URINE.
  • THREE MAJOR CLASSES CLASSES.
  • CARDIOVASCULAR INDICATIONS : Hypertension and heart failure

MECHANISM & rsquo; ACTON :

  • Increase urine output.
  • Inhibit sodium reabsorption, with increase in & rsquo; osmolarity intra tubular and a reduction in water reabsorption.
Figure 1. Schematic representation of the nephron and pharmacological targets different diuretics.

KEY MOLECULES :

  • Diuretics L & rsquo; cove henle : furosemide
  • thiazide diuretics : hydrochlothiazide ,indapamide (thiazide related).
  • Diuretics d & rsquo; potassium-sparing :

– Anti aldostérone : spironolactone,eplerenone.
– Amiloride: blocks the epithelial sodium channel

  • Associations diuretics or diuretics or IEC + + ARAII.

OTHER EFFECTS :

  • Kaliémie :

hypokalaemia and metabolic alkalosis. Especially loop diuretics, but thiazide diuretics.
hyperkaliémie diuretics & rsquo; potassium-sparing

  • paint it : especially with thiazide
  • urinary calcium :

– diuretic s & rsquo; cove : hyper calciurie
– thiazide diuretics: hypocalciurie

  • Hyperuricémie : Diuretics of & rsquo; loop and thiazide diuretics.
  • lipids : increase cholesterol and triglycerides.
  • intolerance CARBOHYDRATES especially if metabolic syndrome
  • OTHER SIDE EFFECTS : gynecomastia (spironolactone), ototoxicité , allergic reaction.

INDICATIONS CARDIOLOGY :

  • essential hypertension : thiazides
  • resistant hypertension : spironolactone
  • Renal failure : Diuretics of & rsquo; cove.
  • Heart failure : Especially loop diuretics, but thiazide diuretics and aldosterone antagonists

CONTRAINDICATIONS : the most important

  • Diuretics of & rsquo; cove : acute renal failure, kidney failure on low barrier.
  • thiazides : severe renal impairment.
  • spironolactone : moderate renal impairment, pregnancy ,feeding with milk

MONITORING TRT :

  • edema , weight , TA, hydration
  • lonogramme especially serum potassium
  • blood creatinine.
  • metabolic balance.

/Users/adlane/Downloads/médecine/4ème année/Cardiologie/Constantine/Cours de 2015:2016/2/media / image4.jpeg
MECHANISM sodium reabsorption : TUBULE PROXIMALE
MECHANISM sodium reabsorption : BRANCH UP OFF Henle
MECHANISM sodium reabsorption : TUBUUE DBTAL
MECHANISM sodium reabsorption : COLLECTOR CHANNEL

Dr Djeghri's course – Faculty of Constantine