General Flashcards
Describe the RAAS system initiated by the kidneys and its effects on blood pressure.
- Reduced Arterial pressure sensed
- Renin released by Juxtaglomerular cells
- Renin is an enzyme that produced angiotensin II
- Angiotensin II effects:
1) Vasoconstriction increasing peripheral resistance (BP = Cardiac output x peripheral resistance)
2) Stimulates aldosterone release from the cortex of adrenal glands which acts on distal tubule and collecting ducts promoting retaining sodium and as a result water
3) Stimulates ADH release from the pituitary
Name the three factors that stimulate release.
1- Sympathetic nerve activation due to baroreceptor feedback
2- Renal Artery hypotension
3- Decreased sodium in the distal tubule
Why do people with kidney problems have hypertension?
1- Activation of the RAAS system
2- Retention of salt and water with reduced excretory function
Name a vasodilator produced around the renal arteries.
prostaglandins (causes efferent vasodilation)
Describe the ‘clinical’ stages of hypertension.
1 = 140/90 with ABPM or HBPM 135/85 2= 160/100 with ABPM or HBPM 150/95 3= 180 systolic and over, or 110 diastolic and over
(If BP measured in the clinic is higher than one of the first values then you need to go on to measure ABPM or HBPM!)
Define hypertension.
A state of elevated arterial blood pressure
What is the blood pressure target for someone:
A) over 80
B) cardiac, renal disease or diabetes
A) 150/90
B) 130/80
Would the following increase or decrease blood pressure:
A) Age
B) Potassium
C) Sodium
A) Increase
B) Decrease
C) Increase
Name 4 risk factors of hypertension.
- Obesity
- Excessive alcohol
- Physical inactivity
- Sodium intake
(Family history)
Name types/categories of drugs that cause hypertension.
- Oral contraceptive pill
- Steriods
- NSAIDs
- Venlafaxine (Anti-depressant)
- illict drugs
Name causes of hypertension.
Primary Hypertension causes:
-Essential Hypertension
Secondary Hypertension Causes:
- Renal Disease (AKI)
- Heart Disease (only one is congenital –> Coarctation of the Aorta)
- Endocrine Disease
- Cushing’s (Excess in cortisol)
- Conne’s Disease (Aldosteronism or excess aldosterone dye to hyperplasia in adrenal glands)
- Phaeochromocytoma (increase in catecholamines)
State the 4 major consequences of hypertension (which can cause death).
1- Heart Failure
2- Myocardial Infarction
3- Renal Failure
4- Stroke
Describe how hypertension can cause heart failure.
Increase in blood pressure –> increase in total peripheral resistance –> increased afterload –> Left ventricular hypertrophy –> increased contractility –> increased oxygen/metabolic demand –> heart failure
What are the effects of the blood vessels? (3 effects)
1- Atherosclerosis (Any small arteries and arterioles but usually affects the heart)
2- Stroke (Narrowing and sclerosis of the cerebral arteries)
3- Retinopathy (damage to the vessels means they are hardened and no longer smooth and narrow –? leads to oedema and haemorrhages damaging the eyes)
Describe the effects of hypertension on the kidneys. (Just gain an understanding of this - this is actually nephrotic syndrome so remember the symptoms of that)
First: Autoregulation of BP by the kidneys tries to protect the kidneys
Second: You start to get albuminuria as there is damage to the basement membrane
Third: as there is continued high blood pressure the arteriolar walls thicken and narrow –> irreversible kidney function decline
Fourth: Urine excretion decreases (volume overload in the body + reduced clearance of creatinine, urea, and waste products)
Describe the indication for prescribing hypertensive medication.
(LO: Medications of hypertension)
- Stage 2 or 3 hypertension
- Stage 1 IF :
- Established CHD
- A 10 year cardiovascular risk of more than >20% or greater
- Target organ damage
- diabetes
- renal disease
What factors dictate Mean Arterial Blood Pressure.
- Cardiac Output (Heart Rate and Stroke Volume)
- Total Peripheral Resistance
What is the pharmacological hypertension treatment for the following groups:
A) The first line of treatment for aged under 55
B) The first line of treatment for aged over 55 OR Black person of African or Caribbean origin of ANY age
C) What if first, the first line of treatment doesn’t work? (Stage 2 of treatment)
D) If hypertension persists? (Stage 3 of treatment)
E) Stage 4 of treatment
A) ACEi or ARB
B) Calcium Channel Blockers (CCB)
C) ACEi or ARB + CCB
D) ACEi or ARB (A) + CCB (C) + Thiazide diuretic (D)
E) Consider another diretic (loop diuretic, sodium channel blocker, or Alpha or Beta blocker
A) Which type of Calcium Channel Blocker do you use for hypertension: Dihydropyridines (E.g Amlodipine) or Non-Dihydropyridines (E.g Verapamil)?
B) Explain why? (MoA)
C) What would you use non-dihydropyridines such as verapamil for? Why?
D) 3 Side effects of CCB?
A) Dihydropyridines
B) Because they block calcium entry through slow channels in smooth muscles in blood vessels more than in cardiac muscle
C) Angina and A.Fib – As it has less vasodilation effect and more cardiac depression effect
D) Headaches, ankle oedema, dizziness (think how it causes vasodilation so less blood to heart and brain being pumped so you get dizzy, or how less blood to the heart so oedema)
A) List 3 side effects of Angiotensin Converting Enzyme Inhibitors.
B) List 3 side effects of Angiotensin AT1 Receptor Blockers. (This is the receptors that angiotensin II binds to in order to have the vasoconstriction effect that it usually has)
C) List 2 contraindications that apply for both drugs
A) Dizziness, headache, persistent dry cough
B) Dizziness, headaches, back/leg pain
C) Hypersensitivity, pregnancy (also bilateral renal artery stenosis or renal artery stenosis in a single functioning kidney)
Thiazide diuretics are used in stage 3 of treatment of hypertension if ACEi/ARBs or CCB did not achieve the required effect.
A) State the mechanism of action of thiazides.
B) State 2 other indications for thiazides other than hypertension
C) What would you use if the person has moderate to severe renal failure instead of a thiazide?
D) Name two other types of diuretics other than loop diuretics and thiazides.
A) Inhibit the Na/Cl cotransporter in the DISTAL tubule so less Na/Cl is reabsorbed + it also acts as a relaxant on smooth muscle so causes vasodilation = reduced oedema and blood pressure
B) (Mild) Heart failure and resistant oedema
C) Hight dose of loop diuretic (E.g Furosemide)
D)
- Aldosterone Antagonist = spironolactone
- Sodium Channel Blocker = amiloride (potassium-sparing diuretic as it blocks the sodium channel blocks coming into the cells but from the lumen of tubule but doesn’t block potassium or affect the sodium-potassium pumps)
(Both act on distal tubule, and collecting tubule and duct)
A) State MOA of Beta blockers.
B) Give an example of a beta blocker.
C) 3 side effects
D) 3 contraindications
A) Sympathetic system antagonists which inhibit/block Beta 1 Adrenoreceptors (Cardioselective) - it acts centrally on the nervous system reducing cardiac output (not as effective as others)
B) Bisoprolol or Atenolol
C) Side Effects: Bradycardia, cold hands and feet, tiredness/fatigue
D) Hypotension, Marked Bradycardia, Uncompensated Heart Failure (uncompensated is acute worsening of heart failure)
A) Describe MoA of alpha blockers.
B) List 3 SEs of Alpha Blockers.
A) Block Alpha 1 receptors (sympathetic nervous system antagonists) –> blocks vasoconstriction = vasodilation
B) Dizziness, Headache, peripheral oedema
Identify key lifestyle factors that contribute to hypertension.
- Excess dietary salt
- Overweight and Obesity
- Poor diet
- Lack of physical activity
- Excess alcohol consumption
- Smoking
- Stress
