Hypertension Flashcards
How do you calculate blood pressure?
CO X SVR
What is high normal BP?
130-139/85-89 so you wouldn’t intervene but could suggest lifestyle changes
What is Grade 1 and grade 2 hypertension?
systolic + 20
diastolic + 10
so stage 1 - 140-159/90-99
stage 2 - 160-179/100-109
What to do when a patient has isolated systolic hypertension?
systolic is > 140 and diastolic is <90
less serious unless in the elderly
lifestyle interventions then drugs is not effective
what is the difference between systolic and diastolic bp?
systolic is max bp during ventricular contraction, diastolic is min bp during relaxation
what is hypotension?
<90/<60
what is postural hypertension?
if systolic decreases by 20 or diastolic by 10 when you stand
who is postural hypotension more common in?
older patients, especially with diabetes or if on some antihypertensives
What are some CNS effects of hypotension?
dizziness
impaired cognition
fatigue
visual disturbances
what are some muscle effects of hypotension?
paracervical ache (upper back) general fatigue
what are some heart effects of hypotension?
angina
how many people have hypertension?
16 million
how many women compared to men have high blood pressure?
30% of women, 32% of men
what is the main reason why systolic bp increases with age?
loss of compliance if arteries
what is the framingham heart study?
study of factors that contribute to cardiovascular disease, intensive monitoring of framingham study led to identification of major CVD risk factors
what did the framingham studies conclude?
hypertensives are a cause for concern as have 6 fold increase in stroke, 3 fold increase in cardiac death and peripheral arterial disease is twice as common
what can hypertension cause?
major RF for much more serious conditions - stroke, coronary heart disease, renal impairment and peripheral vascular disease
Who is particularly vulnerable to hypertension?
diabetics and the obese
how does chronic hypertension damage the heart?
thickened left ventricle due to myocardial hypertrophy to increase pressure in systole overcoming raised end diastolic aorta pressure
why is concentric hypertrophy bad?
stroke volume decreased so tachycardia is required, also hypertrophic cardiac muscle has poor blood supply leading to ischemic damage
Why is eccentric hypertrophy bad?
whole ventricle enlarges, wall may or may not thicken, heart is enlarged so lower systolic pressure produced, reduced SV, weaker heart, maybe heart failure
what is hypertensive retinopathy?
damage to retinal blood vessels as they are particularly sensitive to chronic hypertension
what are ‘silver/copper wire’ arteriolar?
where centre of arteriole shines due to reflected light as get narrowing at points where arteriolar and venules cross?
what are some signs of retinal damage?
silver copper wire arterioles cotton wool spots blot and flame haemorrhages microaneurysms swelling of optic disc
what is the difference between primary and secondary hypertension?
primary we don’t know the cause when secondary is due to renal disease, endocrine disease, coarctation of the aorta, iatrogenic (due to drugs), thyroid disease
is primary or secondary hypertension more common?
primary - 90-95% of cases
secondary - only 5%
how is blood pressure controlled!
baroreceptors in carotid artery (neuronal) for rapid response RAAS system (hormonal) which provides a more steady response
what system is normally defected in chronic hypertension?
RAAS hormonal
what system could be defected in aneurysms or haemorrhagic strokes?
neuronal system as controls moment to moment BP fluctuations preventing sudden spikes
What are the possible causes of hypertension?
impaired production of NO as acts as a vasodilator but when endothelium is damaged by free radicals or cytokines NO production is decreased
raised renin release due to kidney damage
reduced ANP release which is released from the atrial wall heart muscle cells, reduces ECF volume by increasing renal sodium excretion hence increasing water excretion so if lost salt and water retention
what should the treatment be for high renin hypertension
dietary salt restriction
diuretics as water retention
which ethnicity is more sensitive to salt intake?
afro-caribbean
what happens if you reduce salt intake too much?
hyponatremia, brain swelling
what are the symptoms of mild and severe hyponatremia?
loss of energy and fatigue, confusion, muscle weakness
nausea, vomiting, headache, spasms, restlessness, seizures, coma
why are green vegetables in diet important?
foods high in potassium means dietary potassium is increase and helps sodium potassium balance, potassium just as important as sodium
what percentage of 45 year olds type 2 diabetics have hypertension?
40%
what percentage of type 2 diabetics aged 75 have hypertension?
60%
why is hypertension common in diabetics?
damages endothelium and reduces NO production
what causes the link between obesity and hypertension?
high lepton levels as fat cells so increased symp vasoconstriction
hyperinsulinaemia and insulin resistance
what drug treatment should be given for stage 1 hypertension?
antihypertensive if also have organ damage, CD, renal disease, diabetes
what treatment should be given for patients with stage 2 hypertension?
antihypertensives to those of any age
what lifestyle changes should be encouraged?
lose weight
moderate exercise
diet rich in vegetables
low salt diet
what is the first step of treatment?
ACE inhibitors or ARB unless they are Afro Carrib give CCB
What treatment do you give if CCB causes oedema or intolerance or high risk of heart failure?
Thiazide like diuretic
what thiazide like diuretics should be offered?
chlortalidone
indapamide
when should beta blockers be used?
in young people if intolerance to ACE inhib or ARB’s, increased symp drive
otherwise don’t use as risk of diabetes developing
what treatment should be given in step 2 if step 1 doesn’t work?
CCB with ACE inhib/ARB
if can’t use CCB use thiazide like diuretic
what treatment should be given in step 3?
3 drug combo of ACE inhibitor/ARB, CCB and thiazide like diuretic
what treatment should be given in step 4?
resistant hypertension
consider adding 4th antihypertensive or seek expert advice, make sure patient is taking drug
how do CCB’s work?
block entry of calcium, reduce electrical conduction of the heart, reduce force of contraction of muscle cells and dilate arteries
how do thiazide like diuretics work?
block thiazide sensitive sodium chloride symp peter in DCT inhibiting reabsorption so more water moves in DCT and leaves body - increases urinalysis output and decreases body water and salt volume
