anti-hypertensive drugs for nursing students

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Page 1: Anti-hypertensive drugs for Nursing Students
Page 2: Anti-hypertensive drugs for Nursing Students

INTRO

Hypertension is defined as either a sustained systolic blood pressure (SBP)of greater than 140 mm Hg or a sustained diastolic blood pressure of greater than 90 mm of Hg.

An agent that reduces high blood pressure is called as an ANTIHYPERTENSIVE.

Page 3: Anti-hypertensive drugs for Nursing Students

Prehypertension-systolic between 120 to 139 mm/Hg and diastolic between 80 to 89 mm/Hg.

Effects of Hypertension Increases risk of heart disease , heartfailure, kidney

disease, blindness, and stroke. Primary Hypertension- No known reason.Secondary Hypertension-due to some cause such as

kidney disease, abnormalities of adrenal glandswill try nonpharmacological methods first.

Page 4: Anti-hypertensive drugs for Nursing Students

CLASSIFICATION DIURETICS Thiazide Type:

Hydrochlorothiazide,Chlorothalidone,Bendroflume-thiazide,Trichloromethazide

Potassium Sparing: Spironolactone,Amiloride,Triamterene

Loop Diuretics: Furosemide,Ethacrynic Acid,Bumetanide,Torasemide

ACE INHIBITORSCaptopril,enalapril,lisinopril,perindopril,r

amipril.ANGIOTENSIN ANTAGONISTSLosartan,irbesartan,candesartan

Page 5: Anti-hypertensive drugs for Nursing Students

CLASSIFICATION (Cont...)Sympatholytics:Centrally acting drugs – Clonidine and

Methyl dopa.Ganglionic blockers – TrimethaphanAdrenergic Neuron Blockers – Resperpine,

Guanithidine.ß - ADRENERGIC BLOCKERSPropranolol,metaprolol,atenolol.+ß ADRENERGIC BLOCKERSLabetalol,carvedilol. - ADRENERGIC BLOCKERSprazosin.,terazosin,phentolamine

Page 6: Anti-hypertensive drugs for Nursing Students

CLASSIFICATION (Cont....)CALCIUM CHANNEL BLOCKERSVerapamil,diltiazam,nifedipine,felodipine,

amlodipine,lacidipineVASODILATORSHydralazine,minoxidil, sodium

nitroprusside.

Page 7: Anti-hypertensive drugs for Nursing Students

DIURETICS

It enhance the excretion of Na and Water resulting in in plasma volume - Cardiac Output - BP Body Na – Relaxation of vascular smooth muscles

- BP Thiazides are the first line anti hypertensives and

are in expensive, it combined with K+ sparing diuretics is the best way to avoid hypokalemia.

Page 8: Anti-hypertensive drugs for Nursing Students

Loop Diuretics – It is a powerful diuretics their antihypertensive effect is low. It is used only in hypertension with chronic renal failure or congestive cardiac failure.

ACE (Angiotensin Converting Enzyme Inhibitors)

Angiotensin II is a powerful vasoconstrict aldosterone also raises the BP by increasing the blood plasma volume.

ACE inhibitor prevent the formation of angiotensin II and (indirectly Aldosterone) there is vasodilation and decreased in peripheral vascular resistance, resulting in BP fall.

Page 9: Anti-hypertensive drugs for Nursing Students

Vasoconstriction

Increase in BP

Salt & water retention

Blood Volume

Page 10: Anti-hypertensive drugs for Nursing Students

Pharmacokinetics

ACE inhibitors well absorbed(except captopril and lisinopril)

ACE Inhibitors are excreted through

kidney

Page 11: Anti-hypertensive drugs for Nursing Students

AE 1.Persistent dry cough due to bradykinin level is

more common in women. 2.Hypotension,head ache,nausea, abdominal pain 3.Hyperkalemia ,proteinuria,neutropenia 4.Dysgeusia (an altered taste sensation) is more

common in captopril. 5.Angioneurotic edema- ACE inhibitors rarely

cause angioedema with swelling in the lips ,nose, larynx and airway obstruction.

6.skin rashes 7.Teratogenicity

Page 12: Anti-hypertensive drugs for Nursing Students

USES 1.Hypertension

2.congestive cardiac failure (CCF )

3.myocardial infarction

4.coronary artery disease

5.chronic renal failure

6.Scleroderma renal crisis

Page 13: Anti-hypertensive drugs for Nursing Students

PRECAUTION AND CONTRAINDICATION ACE Inhibitors are contraindicated in

pregnancy.

It should not be combined with K Sparing

diuretics.

At the first sign of angioedema ,ACE should be

stopped.

ACE Inhibitors may enhance the plasma level of

digoxin.

Page 14: Anti-hypertensive drugs for Nursing Students

Angiotensin II Receptor Blocker Losartan was the 1st orally effective AT 1 receptor

antagonist. There are 2 sub types of Angiotensin - II

receptors – AT1 & AT2 AT1 receptor are present in vascular and

myocardial tissue, brain, kidney and adrenal glomerular cells.

Losartan has high affinity for AT1 receptors when compared to AT2 receptors.

By blocking AT1 receptors Losartan blocks the effect of angiotensin II.

Page 15: Anti-hypertensive drugs for Nursing Students

Angiotensin II Receptor Blocker (Cont....) It relaxes vascular smooth muscles,

promotes salt and water excretions and reduces plasma volumes, hence the BP also decreased.

Pharmacokinetics Given Orally

Bioavailability is < than 50 %

All extensively protein bound

Excreted by kidney

Page 16: Anti-hypertensive drugs for Nursing Students

Angiotensin II Receptor Blocker (Cont....) Adverse Effects – Hypotension,

Hypokalemia, Angioedema is rare. Uses:

HT (First line drug of choice) Cardiac Failure

Renin Antagonist Aliskiren is a direct renin inhibitor

and was recently introduced. It blocks the effect of renin and there by reducing the BP.

Dose: 150 – 300 mg once daily.

Page 17: Anti-hypertensive drugs for Nursing Students

Sympatholytics These are the drugs acting centrally. Clonidine is a selective 2 agonist. Stimulation of 2 receptors in the CNS. (in the

vasomotor center and hypothalamus) Decrease the central sympathetic outflow, blocks

the release of NA from the nerve terminals, leading to fall in BP.

AE includes drowsiness, dryness of mouth, nose and eyes. Swelling of parotid gland and pain.

Uses – Mild – Moderate HT, Opioid Withdrawal, diabetic neuropathy, with anaesthetics.

Page 18: Anti-hypertensive drugs for Nursing Students

Methyl Dopa is a pro drug, is metabolized in the body to methyl nor ephinephrine, which is an 2 agonist. It reduces central symapthetic outflow leading to a fall in BP.

Uses – Mild - Moderate HT along with Diuretics. It is safe in HT during pregnancy.

Ganglionic Blockers This drugs blocks both symathetic and para

sympathetic ganglions resulting in decreased sympathetic tone and a fall in BP. Trimethaphan is the only ganglion blocker.

Used for surgeries in IV route.

Page 19: Anti-hypertensive drugs for Nursing Students

Adrenergic Neuron Blocker Guanethidine depletes the stores of NA

in the adrenergic neuron and also blocks its release.

It is not used because of its AE. Reserpine is an alkaloid obtained from

‘Rauwolfia serpentina’. It destroys vesicles that store NA and thus depletes the store of these mono amines and reduces the BP.

Adrenergic Receptor Blockers Blockers 1. Non – Selective Blockers like Phenoxybenzamine and

phentolamine are used in the treatment of HT.

Page 20: Anti-hypertensive drugs for Nursing Students

Adrenergic Receptor Blockers Blockers 2. Selective 1 Blockers like Prazosin, Terazosin dilates

both aterioles and venules. Peripheral vascular resistance is decreased leading in fall in BP.

These are mild anti hypertensives. It blocks the 1 receptors results in decreased myocardial contractility and cardiac output. Thus they reduce the BP.

Atenolol is the preferred Beta blockers.

- Blockers

Page 21: Anti-hypertensive drugs for Nursing Students

Advantage of atenelol is once a day dosing.

Absence of CNS side effects is other advantage

Esmolol is the short acting beta blockers, used in intra

operative and post operative hypertension.

& Blockers

Labetalol and Carvedilol block 1 and receptors.

It is used in IV, in the treatment of Hypertensive

emergencies.

Page 22: Anti-hypertensive drugs for Nursing Students

Calcium Channel BlockersThey are another important group of anti hypertensives.They dilate the arterioles resullting in reduced

peripheral vascular resistance.Nifedipine produce some refelex bradycardia while this

is not seen with Verapamil and Diltiazem as they are cardiac depressants.

Uses: it is effective particularly in elderly patients.It may be used in monotherapy in moderate to severe

HT.It is used in sub lingual route for Hypertensive

emergencies.

Page 23: Anti-hypertensive drugs for Nursing Students

Vasodilators It relax the vascular smooth muscles. Thus

reducing the BP. Due to decreased peripheral vascular resistances.

Hydralazine is directly acting arteriolar dilators. The fall in BP is associated with Tachycardia. Adverse Effects Headache, Nausea, Hypotension, Flushings, dizziness and

Palpitation , water retention.

Uses: It is used with beta blockers and diuretics in moderate – severe HT.

Page 24: Anti-hypertensive drugs for Nursing Students

Vasodilators (Cont...) Minoxidil is directly acting arteriolar dilators. In

severe HT not responding to other drugs. It acts by opening K + channel in the smooth muscles resulting in reuced BP.

Diazoxide is directly acting potent arteriolar dilators. It can cause hyperglycemis because it inhibits the insulin secretion

Sodium Nitroprusside is the rapidly acting vasodilators. It relaxes both arterioles and veneules.

AE – Palpitations, Sweating. Nausea and vomiting, Hypotension.

Uses - drug of choice for HT emergencies. MI

Page 25: Anti-hypertensive drugs for Nursing Students

NURSING IMPLICATIONS Risk of fall is evident as vasodilators can cause

postural hypotension. So the patients must be guarded while getting up.

Palpitations can be due to reflex tachycardia induced by a vasodilators.

Sodium nitroprusside acts with in a seconds. BP monitored constantly. It should be disolved in 2 ml of 5 % dextrose

solution. And than diluted in IV fluids.

Page 26: Anti-hypertensive drugs for Nursing Students

NURSING IMPLICATIONS

It is light sensitive, so protected from light by an opaque wrapping.

If color changes infusion should be discarded.

Infusion is prolonged blood level of CN and thiocyanate should be checked.

It should not be prolonged for more than 2 – 3 days.

Page 27: Anti-hypertensive drugs for Nursing Students