CASE ON HTN Flashcards
defined as sustained abnormal elevation of the
arterial blood pressure
HYPERTENSION
• BP of >140/90 (average of 2 or more readings taken on 2 or more visits)
• DBP ≥90 on a single occasion
Repeated, Elevated Blood Pressure Levels
Often asymptomatic until overt organ damage is imminent or has occurred
HYPERTENSION
BLOOD PRESSURE CLASSIFICATION – JNC VII
- Normal
- Pre-HTN
- Stage 1
- Stage 2
SBP: < 120 and
DBP: < 80
Normal
SBP: 120 – 139
or
DBP: 80 – 89
Pre-HTN
SBP: 140 – 159
or
DBP: 90 – 99
Stage 1
SBP: ≥ 160
or
DBP: ≥ 100
Stage 2
CO x TPR
Blood Pressure
Stroke volume (SV) x Heart rate (HR)
CO
CO
Cardiac Output
TPR
Total Peripheral Resistance
size of arterioles
TPR
SITES OF BP REGULATION
- Resistance Arterioles
- Capacities Venules
- Pump Output Heart
- Volume Kidneys
TYPES OF HTN
• Primary or Essential
• Secondary Hypertension
• Age
• Hyperlipidemia
• Overweight
• Genetic/Family history
• Diet (high salt)
• Stress
• Smoking
• Sedentary lifestyle
• Excessive alcohol use
• Diabetes
• Sleep apnea
• Race
Risk factors include in Primary or Essential Hypertension
• Renal causes
• Endocrine causes
• Coarctation of the aorta (narrowing of the aorta)
• Use of drugs (NSAIDS, OCA, cocaine, amphetamines)
• Obesity, DM, Pregnancy, Neurologic disorders
Secondary Hypertension
Renal causes:
• Parenchymal
• Renovascular
Endocrine causes
• Phaeochromocytoma
• Cushing’s disease
• Hyperthyroidism
• Hyperaldosteronism
- ↓ salt intake (Japan, ↑ intake ↑ ↑ BP)
2.5gm/day (250meq) ↓ 1gm/day (100meq) - ↓ calorie intake, weight loss
- ↓ alcohol consumption (low dose ↓ BP)
- ↑ physical activity
- ↓ stress factors
- ↓ smoking
- ↓ caffeine intake
Non DrugTreatment – Life Style Modification
Effects of Lifestyle Modification
Weight reduction
Adopt DASH eating plan
Dietary sodium reduction
Physical activity
Moderation of alcohol consumption
5–20 mmHg/10 kg weight loss
Weight reduction
8–14 mmHg
Adopt DASH eating plan
2–8 mmHg
Dietary sodium reduction
4–9 mmHg
Physical activity
2–4 mmHg
Moderation of alcohol consumption
PHARMACOLOGY OF ANTIHYPERTENSIVE AGENTS
- Diuretics
- Direct Vasodilators
- Angiotensin Blockers
- Sympathoplegic agents
Decrease Na+ and leads to decrease in blood volume
Diuretics
— Relax vascular Smooth Muscle
— Dilate resistance vessels capacitance
Direct Vasodilators
Dec peripheral vascular resistance
Decrease blood volume
Angiotensin Blockers
Dec peripheral vascular resistance
Dec cardiac function venous pooling
Sympathoplegic agents
Agents which promote the excretion of solutes (electrolytes) with iso-osmotic excretion of water
DIURETICS
Osmotic diuretics,
Carbonic anhydrase inhibitors,
xanthine derivatives,
acidifying salts
Proximal Convoluted tubule
Loop diuretics
Ascending limb of the Loop of Henle (AHL/TAL)
Thiazide
Early Part of the distal convoluted tubule (DCT)
Potassium sparing diuretics
Late Distal Convoluted Tubule and Collecting Duct (CCT)
CLASSIFICATION OF DIURETICS
- Proximal convoluted tubule
- Descending loop of Henle
- Ascending loop of Henle
- Distal convoluted tubule
- Collecting duct
— Carbonic anhydrase inhibitors which inhibits the reabsorption of HCP3- in the proximal convoluted tubule.
— weak diuretic properties
ACETAZOLAMIDE
— Inhibit the Na+/ K+ / Cl- co—transport in ascending loop of Henle, resulting in retention of Na+, Cl- and water in the tubule.
— These drugs are the most efficacious of the diuretics.
BUMETANIDE,
FUROSEMIDE,
TORSEMIDE,
ETHACRYNIC ACID
— Inhibit reabsorption of Na+ and Cl- in distal tubule, resulting in retention of water.
— most commonly used diuretics
THIAZIDES
These agents can prevent loss of K+ that occurs with thiazide or loop diuretics
Spironolactone,
Amiloride,
Triamterene
An aldosterone antagonist, inhibits the aldosterone - mediated reabsorption of Na+ and secretion of K+
SPIRONOLACTONE
Block Na+ chanels
AMILORIDE and TRIMTENE
