arterial blood pressure Flashcards
what is blood pressure
the outwards pressure exerted by the blood on blood vessel walls
systemic arterial blood presseure
is the pressure exerted by the blood on the walls of the aorta and systemic arteries when the heart contracts
systemic diastolic arterial blood pressure
is the pressure exerted by the blood on the walls of the aorta and systemic arteries when the heart relaxes
hypertension
140/90mmHg or higher and daytime average of 135/85 mmHg or higher
pulse pressure
difference between systolic and diastolic pressure
normally 30-50mmHg
laminar flow
central flow (not audible through a stethoscope)
fifth korotkoff sounds
point at which sound disappears
first appearance of sound
systolic blood pressure
pressure gradient =
mean arterial pressure - central venous (right atrial) pressure
what is mean arterial pressure
the evragae arterial blood pressure during a single contraction and relaxation
diastolic (relaxation) is
twice as long as contraction (systolic)
MAP=
[(2xdiastolic pressure) + systolic pressure] / 3
normal arterial blood pressure
140/90
MAP of at least 60 mmHg is needed to
perfuse the coronary arteries, brain and kidneys
systemic vascular resistance
the sum of resistance of all systemic vascular resistance
the major resistance vessels
arterioles
baroreceptor reflex
short term regulation of mean arterial blood pressure
the baroreceptor reflex is important in
moment to moment regulation of arterial blood pressure including prevention of postural changes
postural hypotension
results from failure of baroreceptor responses to gravitational shifts in blood, when moving from horizontal to vertical position
hypotension risk factors
age related medications certain diseases prolonged bed rest reduced intravascular volume
postural hypotension
drop of 20 mmHg in systolic - with or without symptoms
drop of 10 mmHg with symptoms diastolic
baroreceptors only respond to
acute changes in blood pressure
hormones that regulate extracellular fluid volume
RAAS
