Hypertension Flashcards
Define hypertension
A condition where blood pressure is elevated to an extent that lowering is of clinical benefit
What is stage 1 hypertension?
greater than or equal to 140/90 mmHg
What is stage 2 hypertension?
greater than or equal to 160/100 mmHg
What are the complications of hypertension?
- myocardial infarction
- stroke
- HF
- Hypertensive encephalopathy
- Renal Failure
- Hypertensive nephrosclerosis
- Peripheral vascular disease
What thiazide diuretics are used?
Bendroflumethazide, Chlortaldone, Hydrochlorothiazide, Indapamide
What loop duiretic is used?
Furosemide
What Aldosterone antagonist is used?
Spironolactone
What ACEi are used?
Captopril, ramipril, enalapril, imidapril, lisinopril, perindopril, quinapril
What ARBs used?
Candesartan, irbesartan, losartan, temisartan, olmesartan
What renin antagonist is used?
Aliskiren
What is the mechanism of Acei?
block the conversion of angiotensin I to angiotensin II
What is the mechanism of ARBs?
Block the action of angiotensin II at the type 2 receptor
What is the side effect of ACEi?
Persistent dry cough
Rash, renal failure, angioedema
What monitoring is required for ACEi?
- Renal function
- Potassium
- Blood pressure
- Creatinine (until required dose is reached then 6-12 months thereafter)
What is the consequence of antagonism of ACE?
Leads to vasodilation, potassium retention, inhibition of salt and water.
What are some Beta Blockers?
Acebutolol, Atenolol, Bisoprolol, Carvedilol
What is the mechanism of beta blockers?
They block the beta-adrenoreceptors in the heart, peripheral vasculature, bronchi, pancreas and liver.
Beta-1-receptors are predominant in the heart and kidney whereas Beta-2-receptors are predominant in other organs
Kidney: Blocking the beta-1-receptors causes inhibition of renin from juxtaglomerular cells and thereby reduce the activity of angiotensin-aldosterone system.
Heart: blockade of the beta-1-receptors in the sino-atrial node reduces heart rate and blockade of beta-1-receptors in the myocardium decrease cardiac contractility.
Central and peripheral nervous system: blockade of the beta-receptors in the brainstem and the prejunctional beta-receptors in the periphery inhibits release of neurotransmitters and decreases sympathetic NS activity.
What are alpha-adrenoreceptor antagonists
Alpha receptors are used as add on drugs to treat hypertension or where other drugs are poorly tolerated.
They act selectively at post-ganglionic alpha-1-receptors which leads to vasodilation and reduction in BP
What are the adverse effects of Alpha blockers?
First dose postural hypotension
What are some of the names of alpha blockers?
Doxazosin, Indoramin, Prazosin, Terazosin
Name some calcium channel blockers
Dihydropyridine derivatives: amlodipine, felodapine, lacidipine, isradipine, nicardipine
Phenylalkylamine: Verapamil
Benzothiazipine derivative: Diltiazem
What is the mechanism of calcium channel blockers?
They block calcium channels in the peripheral blood vessels/heart. CCBs promote vasodilator activity by reducing calcium influx into vascular smooth muscle cells by interfering with voltage-operated calcium channels in the cell membrane
Dihydro work on L-type calcium channels in peripheral arterioles
What are the adverse effects of dihydro derivative CCBs?
Headache, flushing, swelling of ankles an hands, gum hypertrophy
What are the adverse effects of verapamil? (CCB)
Constipation
What non-pharmacological interventions can help hypertension?
- Weight reduction
- Diet changes - whole gain bread, brown rie. 5 a day, low fat foods, low sodium intake, cut alcohol intake
- Quit smoking
- Encourage exercise
When would you prescribe a loop diuretic for hypertension?
When renal function is significantly impaired
What are inotropic drugs?
Inotropic drugs work on the force of contraction
Positive inotropic drugs increase Ca2+
Negative inotropic drugs decreaseCa2+
What are Chonotropic drugs?
Work on the heart rate
Positive chronotropic drugs increase heart rate
Negative chronotropic drugs decrease heart rate
How does digoxin (positive inotropic) work?
Inhibits the cell membrane Na/K ATPase which leads to reversal of Na/Ca2+ exchange
Increased intracellular Ca2+ results in increased strength of contraction
Also affects electrical physiology of the heart by blocking AV conduction and reducing heart rate
What are the signs and symptoms of digoxin toxicity?
- Bradycardia
- Arrythmia
- Nausea, Vomitting
- Confusion
- Visual disturbances
- Metabolic or electrolyte disturbances
What are the sympathomimetics?
Acts on B1 receptors causes tachycardia and increased force of contraction
Dopamine and dobutamine
