Peripheral vascular disease, hypertension and dissection Flashcards
What are the primary determinants of blood pressure
volume status
sympathetic nervous system
RAAS
positive chronotropes
increases heart rate
negative chrotropes
decreases HR - Beta blockers
what are factors that increase HR
sympathetic NS
increased thyroid
hypoxemia and acidosis
what are factors that decrease HR
Parasympathetic innervation
athletes
medications: BB, CCB
what determines stroke volume
EDV - amount in the ventricle right before contraction. typically 120mL
what increases the afterload which increases how much the heart has to work/pump against
systemic vascular resistance
aka total peripheral resistance
what determines the systemic vascular resistance
vasodilation and vasoconstriction
what is elevated systolic BP
120-129 mmHG
what is stage 1 systolic BP
130-139 mmHg
what is stage 2 systolic BP
> 140mmHg
what is stage 1 diastolic BP
80-89 mmHg
what is stage 2 diastolic BP
> 90 mmHg
what is released with parasympathetic nervous system stimulation
increase acetylcholine release from vagus nerve
what occurs with the adrenal medulla during times of HTN
inhibits during HTN which will decrease production of catecholamines
decrease B1 and A1 receptor stimulation - decrease HR, decrease squeeze, decrease BP
what is the elevated BP response
renal modulation during HTN will cause decreased RAAS activation
decreased vasoconstriction
decreased sodium excretion
heart strain from HTN will cause natriuretic peptide release (think BNP) which will also decrease RAAS
what releases renin
kidney
what releases angiotensin
liver
what are risk factors of primary HTN
smoking, OSA, obesity, anxiety/stress, family hx of HTN, ETOH, DM
what are likely causes of secondary HTN
renal disease
renovascular disorder
adrenal gland pathology
thyroid dysfunction
head trauma with decreased ICP (Cushings triad)
preeclampsia/eclampsia
aortic coarctation
medication SE
what is malignant hypertension
severely elevated BP >180/110
what is a hypertensive emergency
acute end-organ damage secondary to elevated BP
what is hypertensive urgency
stable end-organ disease (LVH -> CHF)
what is severe uncontrolled HTN
no end-organ damage but highly elevated BP
what are the downstream effects of high blood pressure
ischemic heart disease - supply/demand mismatch
AKI/CKD
encephalopathy
HTN retinopathy
dissection, aneurysm
atherosclerosis
lunar infarcts, ruptured brain aneurysm, subarachnoid hemorrhage
what are the vessel wall layers
Tunica intima
tunica media
tunica externa (adventitia)
vasa vasorum
what is aortic dissection
separation allowing for the accumulation of blood between the tunica intima and tunica media
false lumen is created that will progressively increase in size os the blood spreads in the false tract
what are the primary causes of aortic dissection
most commonly associated with HTN, smoking, advanced age and hyperlipidemia
these increase sheer stresses
what can happen with a false lumen with aortic dissection
rupture
create down stream reentry site to connect with true lumen
enlarge to compress or occlude the true lumen resulting in decreased perfusion
form hematoma within the intimal defect
what are risks for aortic dissection
hypertension
connective tissues d/o: ehlers danlos, marfans
bicuspid aortic valve - increased risk of turbulence
coarctation of the aorta - increased risk of turbulence
what are the most common trauma injuries associated with aortic dissection
acceleration/deceleration injuries
trauma from iatrogenic sources
what is the presentation of aortic dissection
abrupt onset of check of abdominal pain, often described as ripping or tearing
pulse difference in extremities or BP difference between then of >20 mmHg
widened mediastinum or aorta on imagine
what are risk factors for aortic dissection
male
>50yo
HTN
Cocaine or amphetamine use
bicuspid aortic valve
hx of aortic valve replacement
connective tissue disorder
pregnancy
what are risk factors for aortic aneuryms
connective tissue disorders
trauma
dissection
aortitis
atheroscerosis*
what is the ruptured AAA triad
abdominal or back pain
hypotension
pulsatile abdominal mass
how quickly does mortality rate increase with AAA ruptures
increase by 1% per minute prior to arrival to the ED
what is peripheral artery disease
occlusion/narrowing reduce the blood flow to distal tissues
results in ischemia and can lead to nephrosis
what is chronic venous disease
decrease functioning of the venous system resulting in obstruction, venous hypertension, varicose veins
what occurs at the renal arteries
blood pressure regulation
