Lab 8- Cardiovascular Physiology

what is the difference between AV and semilunar valves

AV valves are between atria and ventricles, semilunar valves are between ventricles and great vessels

3 structures that ensure one-way blood flow

valves, chordae tendineae, papillary muscles

pulmonary artery

carries deoxygenated blood to lungs

pulmonary veins

carries oxygenated blood to heart

aorta

carries oxygenated blood into the body

diastole

when chambers relax

systole

when chambers contract

what is the order of A/V diastole and systole

VD > AS > VS > AD

driving pressure

ventricular pressure, it drives blood throughout

S1 sound: what does it sound like, what causes it and when

"Lub", from AV valves closing at the beginning of ventricular systole

S2 sound: what does it sound like, what causes it and when

"Dub", from the SL walves closing at the end of ventricular systole

auscultation

listening to heart sounds with stethoscope

5 positions for auscultation

aortic, pulmonary, mitral, triscupid valves and Erb's point (S2 sound between P and T)

where is blood pressure highest

in the aorta

where is blood pressure lowest

in the superior/inferior vena cavae

what materials are used for manual blood pressure

sphygmomanometer and stethoscope

where is the stethoscope placed for manual BP

at the brachial artery in the cubital fossa

how should a patient be positioned for a bp reading

sitting relaxed with legs uncrossed

what do you inflate the BP cuff to initially

160-180mmHg

Korotkoff sounds

sounds from blood flow through a compressed artery, right after opening valve

when do systolic and diastolic pressure occur according to heart sounds

systole is at the beginning of sounds and diastole is at the end of sounds

factors that affect blood pressure

anxiety, position, age, weight, sex

4 phases we hear once valve is opened

1) fairly sharp thudding, systole > 2) softer murmur for 10-15mmHg > 3) sounds become louder and sharper > 4) sounds muffle and cease, diastole

how is blood pressure calculated

systolic/diastolic

how is pulse pressure (PP) calculated

systolic - diastolic

how is mean arterial pressure (MAP) calculated

diastolic pressure + 1/3 x pulse pressure

what are the 2 things peripheral resistance depends on

diameter of blood vessels, viscosity of blood

how is cardiac output calculated (ml/min)

heart rate (BPM) x stroke volume (mL)

how is total peripheral resistance calculated

MAP = cardiac output x total peripheral resistance

orthostatic hypertension

when blood pressure rises significantly upon standing

how does body lower high blood pressure

baroreceptors monitor and send signals to dilate vessels, decrease heart rate, and increase na/h2o excretion to lower blood volume

normal BP

<120/<80

elevated BP

120-129/<80

stage 1 hypertension BP

130-139/80-89

stage 2 hypertension BP

>140/>90