Different drug regularity bodies in different countries.
8. hypotension & hypertension
1. Drugs for the management of hypotension &
hypertension
2. Introduction
Hypotension:
•BP below 100 / 60 mm Hg in women and less than 110 / 70
mm Hg in men.
•orthostatic hypotension (orthostasis = standing upright), the
blood rushes into the lower parts of the body when sitting down
or standing up fast.
4. Drugs used to treat hypotension
If cerebral, renal, and cardiac perfusion is maintained,
hypotension itself does not usually require vigorous direct
treatment
Sympathomimetic agents
Used in a hypotensive emergency to preserve cerebral &
coronary blood flow. The treatment is usually of short duration
while the appropriate intravenous fluid or blood is being
administered.
Direct-acting α agonists
• Norepinephrine,
• Phenylephrine, & Methoxamine
5. Direct-acting α agonists
Norepinephrine (Noradrenaline) is an agonist at
•both α 1, α 2, & β 1 receptors.
•↑peripheral resistance = ↑diastolic & systolic BP.
Phenylephrine pure α 1 agonist.
•longer duration of action than the catecholamines.
•↑peripheral resistance = ↑diastolic & systolic BP.
Methoxamine α 1 -receptor agonist.
• prolonged duration of action
•vagally mediated bradycardia.
6. Shock
• Complex acute cardiovascular syndrome that results in a
critical ↓ in perfusion of vital tissues & a wide range of
systemic effects.
• Usually associated with hypotension, an altered mental state,
oliguria, & metabolic acidosis.
• If untreated, it progresses to a refractory deteriorating state &
death.
Mechanisms responsible for shock :
• Hypovolemia, cardiac insufficiency, & altered vascular
resistance.
Volume replacement & treatment of the underlying disease are
the mainstays of the treatment of shock.
7. Shock
Cardiogenic shock and acute heart failure, usually due to
massive myocardial infarction, has a poor prognosis.
•Dopamine or dobutamine : positive inotropic drugs
•Dopamine acts on
β1 receptors ( cardiac stimulation)
dopaminergic receptors (renal & mesenteric vasodilation)
α1 receptors (vasoconstriction)
•Dobutamine acts on β1 ( cardiac stimulation)
8. Shock
Anaphylactic shock :
•Type I hypersensitivity reaction that affects both the respiratory
& the cardiovascular systems causing
•bronchospasm, mucous membrane congestion, angioedema, and
severe hypotension
•Inj Adrenaline, 0.3–0.5 mg IM
•Activates α, β1, and β2 receptors, all of which may be important
in reversing the pathophysiologic processes underlying
anaphylaxis
•Glucocorticoids and antihistamines (both H 1 - and H 2
-receptor antagonists) may be useful as secondary therapy in
anaphylaxis.
9. Introduction
Hypertension is the most common cardiovascular disease.
Sustained hypertension damages blood vessels in kidney, heart,
& brain and leads to an ↑incidence of renal failure, coronary
disease, cardiac failure, and stroke.
Normal Blood Pressure : Systolic 120 -129 mm Hg
Diastolic 80 – 84 ,,,,,,,,,,,
Mild Hypertension : 140 -159/90-99 ,,,,,,,,,,,,
Moderate Hypertension 160 -179/100-109 ,,,,,,,,,,
Severe Hypertension : >180/>110 ,,,,,,,,,,,
10. Introduction - III
Etiology:
• > 90% Unknown – Essential Hypertension ( so called because
it was originally thought the raised BP was essential to
maintain adequate tissue perfusion)
• Secondary to known organic diseases such as Renovascular
disease, Coarctation of aorta, Pheochromocytoma, Cushing’s
disease, Hyperaldosteronism, etc.
– The therapy is directed towards correction of underlying disease.
Risk factors:
• Smoking, Hyperlipidaemia, Diabetes mellitus, Obesity &
history of any cardiovascular disease.