dr wesa
مشرف
عدد الرسائل : 65
العمر : 38
تاريخ التسجيل : 09/11/2007
 | | موضوع: hypertension treatment الخميس مارس 06, 2008 5:42 pm | |
| Hypertension Treatment Difintion
hypertension: a sustained blood pressure above 140/90 which has to be detected by at least three measurment under the same circumstances you must consider the age and the sex of the patient when you wan't to assian a pateint as hypertensive so 140/90 is not a fixed value Normal blood pressure
Optimum blood pressure 120/80
Normal blood pressure 130/85
High normal blood pressure 139/89 so the range of blood pressure varies from 120-139/80-89 Types of Hypertension
Primary or secondary
Primary hypertension
also called essential hypertension
the actual cause of the hypertension is unknown
most patinet suffring from this type of hypertension
Secondary hypertension
hyprtension result from a disease from a disease or drug therapy Treatment of hypertension
the treatment of hypertension could be pharmological or non-pharmacological
the nonpharmacological tretament includes reduction of body mass index (weight) salt intake, lipids, alcohol, smoking Important point
Arterial Blood pressure = Cardiac Output X Peripheral resistence so by affecting the cardiac output or the peripheral resistence we can treat Hypertension Peripheral ResistenceResistence is the friction or tension or hindrance, against which the blood flows and this friction is remarkable in the peripheral vessels particulary in arterioles
so when pheripheral resistence is decreased , diastolic pressure is less and when
peripherial resistence is more the diastolic pressure rise
for example if the diameter of the blood vessesls decrease the peripheral resistance increase so the pressure increase Cardiac output
cardiac output is the amount of blood pumbed from each ventricle, usually it refers to the left ventricle output through the aorta into various organs of the body
whenever the cardiac output is increased, the systolic pressure pressure is increased, and when cardiac output is less, the systolic pressure is reduced
cardiac out is directly proportional to blood volume. when blood volume increase, ventricular filling is more, cardiac output is more and presseure rise. when the blood
volume reduced , the cardiac output is less and blood pressure falls Regulation of Arterial Blood pressure
Body has four mechanisms to maintain the blood pressure within normal limits
- nervous mechanism or short term regulatory mechanism
- renal mechanism or long term regulatory mechanism
- hormonal mechanism
- local mechanism
Antihypertensive drugs
Diuretics , which cause reduction in the ECF volume and blood volume , so the blood pressure is decreased
Beta blockers , block the sympathetic beta receptors, so that there are reduction in cardica output and inhibition of the vascoconstriction leading to fall in blood pressure
calciume channel blockers , drugs that blood block calcium channel in the myocardium , causing a decreas in the bood pressure
inhibitors of angiotension converting enzyme, these drug reduceblood pressure by blocking the formation of angiotensin
vasodilators, these agent reduce blood pressure by causing vasodilatation So in general the treamtment of hyprtension could be by one of the following mechanism
Diuretics
drug that interfer with the renin angiotension system
drugs that decrease the peripherial resistence or cardiac outputDiuretics Diuretics : are drugs that increase the excretion of water and slats into the urine
Diuretics include the following
Thiazides
Loop diuretics
Potassium sparing diuretics Mechanism of action
initially the blood pressure falls because of decrease in blood volume , venous return, and cardiac output. Gradullay the cardiac out put returns to normal but the hypotensive effect remains because the peripheral resistence has in the mean time decreased, an. indrict consequence of persisting Na and voulme defict . in general each type of diuretics affect different type of the kidney Thiazides
E.g,. hydrochlorothiazides
Used for mild to moderate cases
reduce blood pressure by 10-15 mmHg
have direct vasodilator effect
adverse effect
Hypokalemia (decrease the level of potassium
Hyperglycemia
Hyperuricemia
hypercalcimia
hyperlipidemia
from the above side effects we can see that Thiazides causes hyperuricemia, so this drug should not be used in persons suffers from gouty arthritis (gout
Also it cause Hyperglycemia (increase the level of glucose in the blood ) so must condricated in the patient with diabetes because it will aggrevate their condition
affecting the distal convoluted tubule
Loop Diuretics
e.g., Furosemide
the word Loop used to donate the structre of the kidney which affected by this type of diuretics which in this case is Loop of helene
most powerful antihypertensive than Thiazides
used in emergency cases ; because it has short duration of action
could be admenistrated by injection intravenously in case od edema
Adverse effect
* hypokalemia
*hyperglycemia
*Ototoxicity
*hypocalcemiaaffect the asecending loop of henle
Potassium Sparing Diuretics
e.g., spironolactone
weakest diuretics also called low efficacy diuretics
always used in combinations
used by the patient under the long treatment of thiazides or loop duretics to replace potassium loss
adverse effect
Hyprkalemia *
Gynaecomastia increase of the breast size *
affect the collocting tubede wesa  | |
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