Hypertension Flashcards
What is hypertension?
Systolic BP greater/ equal to 130
Diastolic BP greater/ equal to 80
Measured on 2 separate occasions
Types of hypertension
Primary/essential
Secondary
Which types of HTN should be ruled out with 24hr ABPM (ambulatory BP monitor)?
White coat HTN (at office BP high, BP low at other places)
Masked HTN (opposite of white coat)
Essential hypertension accounts for 95% HTN cases.
Most common in 25-50 y/o plus family Hx. What are the underlying mechanisms that cause essential HTN?
- Increased SNS activity (NE on heart, vessels and increase renin)
- Increased RAAS activity
- high Na (retention)/low renin HTN [common in African American hence cannot use ACEI & ARBS]
- Age
*high renin, high angiotensin II, high BP
Risk factors of primary HTN
Age
Diabetic
Alcoholic
Smoking
High amount of sodium and fatty food
Secondary HTN accounts for 5% of HTN cases. Often happens in less than 30y/o with sudden, severe, refractory HTN. (Refractory: meaning starting a few antihypertensive drugs but still can’t keep BP in control)
Causes of secondary HTN?
1.renal causes:
-fibromuscular dysplasia (women>men)
-renal artery stenosis
*the above causes lead to low renal blood flow which increase renin then increase BP
-diabetes mellitus nephropathy
-glomerulonephritis
-polycystic kidney disease
*the above causes lead to low GFR, hence increase renin and BP
- Drug related causes:
a) sympathomimetics
-cocaine (increases SNS activity)
b) oral contraceptive
-estrogen (increase angiotensinogen and hence increase angiotensin II and BP)
c) NSAIDS
-vasoconstriction hence low GFR then increase renin and Na retention - Endocrine causes:
a) hyperaldosteronism
b) Cushing’s syndrome (high cortisol -moon faces, abdominal striae, buffalo hump)
c) pheochromocytoma (high NE +EPI)
d) hyperthyroidism (high T3 and T4 means increase in HR ,decrease tone in vessels)
e) hypothyroidism (low T3 and T4, increase tone in vessel)
f) hyperparathyroidism (high PTH, high Ca lvl for SM, increase contraction) - Cardiac causes:
Coarctation in aorta - Pulmonary causes:
Obstructive sleep apnea - Neurological causes:
Cushing’s Triad (high BP, low HR, irregular resp)
High ICP
Antihypertensive agents with respective adverse effects
Enalapril- dry cough
Furosemide-hypokalemia
Prazosin- first dose hypotension
Propranolol- masking signs and symptoms of hypoglycaemia
Match the antihypertensive agents with respective relative/absolute contraindications
Enalapril- hypertension with pregnancy
Propranolol- hypertension with bronchial asthma
Hydrochlorothiazide- hypertension with arthritis gouty
A 52-year-old man who has a history of hypertension is recently diagnosed with type 2 diabetes mellitus with stage 2 diabetic nephropathy. Despite receiving the maximal dose of amlodipine, his blood pressure is not well controlled over the past month. The attending physician decides to add another anti-hypertensive agent.
Which anti-hypertensive agent should be added for this patient?
Enalapril
- In hypertension with diabetes mellitus especially with diabetic nephropathy, ACEI are preferred because ACEI are known to delay the progression of nephropathy.
Site of action of thiazide diuretics
distal convoluted tubule
A drug which causes coronary steal syndrome
nifedipine
MOA of frusemide
Loop of Henle
MOA of spironolactone
collecting tube
MOA of prazosin
selective alpha 1 receptor blocker
Hyperkalaemia is a side effect of
spironolactone
