Pressure & Flow In Arteries & Veins 1 Flashcards
Describe how arterial pressure can be measured using an line.
terial pressure can measured using an arterial line, which is a thin catheter inserted into an artery, typically the radial artery at the wrist or the brachial artery at the elbow.
Define auscultation in the context of measuring blood pressure.
Auscultation is the act of listening for Korotkoff sounds using a stethoscope and sphygmomanometer to measure blood pressure.
How are Korotkoff sounds described in relation to blood flow?
Korotkoff sounds are described as turbulent blood flow heard through a stethoscope when blood starts spurring through the artery as cuff pressure falls below systolic pressure.
Describe the components of a sphygmomanometer.
A sphygmomanometer consists of an inflatable cuff placed around the upper arm, a pump to increase pressure in the cuff, a pressure gauge showing pressure in mmHg, and a valve to release pressure.
Define laminar flow in the context of blood flow.
Laminar flow refers to smooth, uninterrupted blood flow in an artery without turbulence.
How is diastolic pressure related to Korotkoff sounds during blood pressure measurement?
When cuff pressure falls below diastolic pressure, normal laminar blood flow is restored, and Korotkoff sounds cease to be heard.
Describe the significance of the peak and trough in an arterial pressure wave.
The peak represents systolic blood pressure, while the trough represents diastolic pressure in an arterial pressure wave.
How does the cuff pressure relate to the occurrence of Korotkoff sounds during blood pressure measurement?
Korotkoff sounds are heard when cuff pressure falls below systolic pressure, allowing blood to spurt through the artery, creating turbulent flow and audible sounds.
Describe the process of measuring blood pressure with a manual sphygmomanometer.
The process involves listening for Korotkoff sounds, which indicate the pressure in the arteries. The sounds change as the pressure cuff is slowly deflated, allowing for the determination of systolic and diastolic pressures.
Define Korotkoff sounds.
These are the sounds heard through a stethoscope when measuring blood pressure with a manual sphygmomanometer. They indicate the flow of blood through the arteries as the pressure cuff is deflated.
How do automatic blood pressure machines differ from manual sphygmomanometers?
Automatic machines measure oscillations in the arteries instead of Korotkoff sounds. They use these vibrations to calculate mean arterial pressure and estimate systolic and diastolic pressures.
Describe the process by which automatic blood pressure machines calculate blood pressure.
These machines detect oscillations in the arteries, find the peak vibrations as the mean arterial pressure, and use algorithms to estimate systolic and diastolic pressures.
What is the role of the aorta in the measurement of arterial pressure?
The aorta acts as a pressure reservoir during systole when blood is ejected into it, and during diastole, its elastic recoil helps maintain blood flow by pushing on the column of blood.
Do different brands of automatic blood pressure machines provide the same measurements?
Different brands may use slightly different algorithms, leading to slightly varied measurements. However, they generally have similar advantages and disadvantages.
How does the accuracy of manual blood pressure measurements get affected?
The accuracy can be subjective due to factors like background noise, stethoscope fit, and individual hearing abilities. This subjectivity can lead to discrepancies in recorded blood pressure values.
Describe the advantages of using automatic blood pressure machines.
Automatic machines are non-invasive, cost-effective, easier to use, and quicker than manual sphygmomanometers. They provide continuous measurements and require less user skill for accurate readings.
Describe the components of a typical pressure in the cardiovascular system.
The wave includes a steep phase, peak systolic blood pressure, a dicrotic notch caused by aortic valve closure, a gradual falling phase due to aortic elasticity.
How does stroke volume influence the pressure wave in the cardiovascular system?
Increased contractility and pumping force lead to a more rapid rising phase and higher systolic pressure.
Define the impact of arterial elasticity on the pressure wave.
Decreased elasticity with age causes systolic pressure to rise and diastolic pressure to fall due to reduced pressure reservoir function.
What role does total peripheral resistance play in the pressure wave?
It affects the falling phase post-aortic valve closure, with higher resistance leading to a more gradual fall and higher diastolic pressure.
Describe the effect of arteriole constriction on the pressure wave.
Constriction increases total peripheral resistance, resulting in a more gradual falling phase and higher diastolic pressure.
How does arteriole dilation impact the pressure wave in the cardiovascular system?
Dilation reduces total peripheral resistance, leading to a steeper falling phase and lower diastolic pressure.
Describe how blood pressure changes with age.
Blood pressure tends to rise as individuals age due to factors like the loss of elasticity in blood vessels.
Define mean arterial pressure.
Mean arterial pressure is the average pressure in a person’s arteries during one cardiac cycle.
