Anti-Hypertensive Drugs, Blood Pressure & Blood Clotting Drugs Flashcards
Blood pressure equation
BP= TPR x CO
What determines Cardiac Output
Venous return,blood volume, stroke volume, heart rate
Hypertension value (constant)
140/90
Ischaemic Heart Disease, Strokes, Peripheral Vascular Disease caused by high or low bp
High BP
Causes of high BP
ethnic predisposition, genetic factors, low birth weight, environmental factors, drugs, kidney and cardiovascular disease.
Initial treatment
lifestyle change
baroreceptors in carotid sinus cause a response via the S.A node by sending information to
the medulla
ACE Inhibitors end in…..
pril…..e.g, captopril, lisinopril
Normally renin causes angiotensinogen into angiotensin 1 then ACE in lungs convert it to angiotensin 2 leading to
aldosterone secretion and vasoconstriction.
If ACE is blocked
vasodilation occurs, bp lowers. TPR lowers.
Side affects of ACE Inhibitors
hypotension, renal problems, dry cough, rash
Renin-angiotensin systems responsible for
long term BP control
Angiotensin receptor antagonists end in
artan….e.g- losartan, valsartan (less side effects than ACE Inhibitors)
Beta blockers end in
olol….e.g- Atenolol, propranolol
Beta blockers (B1) reduce
Cardiac Output & Renin release
Atenolol
reduce vasoconstriction in sympathetic system
Propranolol
reduce HR/ force, increase renal blood flow
Side effects of Beta Blockers
lethargy, aching limbs, erectile dysfunction.
Alpha Blockers block action of
adrenaline & N adrenaline causing vasodilation
Alpha Blockers end in
osin….e.g- Doxazosin, Prazosin
Thiazide like diuretics end in
ide….e.g- bendroflumethiazide, indapamide
Effect of thiazide like diuretics
increase urine output, lower BP & blood volume
Calcium Channel Blockers end in
pine…e.g- Nifredipine, nicardipine
effect of CCB’s
raise HR, cause vasoconstriction
Potassium sparing diuretics given alongside
Thiazide diuretics
Loop diuretics used in which cases only
severe cases
Heparin & warfarin are
anticoagulants
Heparin + and -‘s
present in liver, increases rate of complex formation, risk of haemorrhage, can only be given IV or Subcutaneously.
Heparin activates antithrombin which….
works against thrombin to form complexes with activated clotting factors
Warfarin + and -‘s
oral, factors 2 (prothrombin), broader effect, slow onset, influenced by vitamin k and foods, risk of haemorrhage and must be strictly monitored.
Rivaroxiban used with patients who have
warfarin resistance
Aspirin is an
anti platelet drug
Aspirin irreversibly blocks
COX enzyme which reduces TXA2 Synthesis and platelets cannot synthesis the new enzyme
Anti platelet drugs increase…..
cAMP levels in platelets
anti platelet drugs decrease….
glycoprotein 2b & 3a on platelets, reduces synthesis of TXA2 in platelets
