Q Sec 3

What characteristics exhibited by normal arteries keeps blood flowing when the heart is between contractions?

compliance and capacitance

What is the key physiological point to remember during the heart's Isovolumetric Relaxation and Isovolumetric Contraction cycles?

all four heart valves are closed

What happens to blood flow when it encounters a "critically stenosed" artery?

all are correct

Which of the following will increase frictional energy losses in the cardiovascular system?

all are correct

Which statement about hemodynamics is correct for vessels connected in series?

overall flow resistance increases

Where is the highest resistance to blood flow found in the normal cardiovascular system?

arterioles

What is "pulsatile" blood flow?

flow that rapidly accelerates and gradually decelerates

Approximately what percentage of the cardiovascular system's blood is stored in the venous system of a person at rest?

65%

What happens to overall flow resistance when vessels are connected in parallel?

flow resistance decreases

Where is the second highest resistance to flow noted in the normal cardiovascular system?

capillaries

Which statement about hemodynamics is correct for vessels connected in series?

overall flow resistance increases

What is the key physiological point to remember during the heart's Isovolumetric Relaxation and Isovolumetric Contraction cycles?

all four heart valves are closed

How does the body maintain volumetric flow to distal organs in the presence of an arterial stenosis?

increased flow velocity through the stenosis

What is the cardiovascular significance of the increase in vessel size from the venules to the IVC?

this allows the low pressure blood to flow easily back to the right atrium

Which physical characteristic of an artery has the greatest influence on its capacitance?

Elasticity

What causes the extensive pressure drop when blood flows from the arterial system, across the capillary beds, and into the venous system?

high resistance to flow in the arterioles and capillaries

What happens to venous flow from the lower extremities when a normal patient inhales?

decreases

Spectral envelope

What does a “clear” spectral window indicate in a spectral Doppler waveform?

Laminar flow

What is the normal venous pressure in the extremities?

15.0mmHg

What mechanism is used to regulate the capacitance of the venous system?

vasomotor tone

What prevents reverse flow of blood in the veins of the upper and lower extremities

numerous one-way valves

A normal adult is standing with both arms raised above their head. Where would the highest and the lowest hydrostatic pressures be measured, respectively?

feet, finger tips

turbulent

Where would a sonographer expect to see a normal triphasic arterial spectral Doppler waveform?

superficial femoral artery

Where is the “Zero Reference Point” for hydrostatic pressure?

Right atrium of the heart

What is the significance of an obscured spectral window indicate a spectral Doppler waveform?

Possible turbulent flow

Why is some of the flow in this spectral waveform of the common femoral artery (CFA) reversed (below the zero flow baseline)?

The artery supplies a high resistance vascular bed

What happens in a normal cardiovascular system when the vasomotor tone is increased?

all are correct

Which term describes lower extremity pain brought on by exercise?

claudication

What happens in the vascular system when an arterial stenosis lowers the amount of blood going to the end organs?

distal arterioles dilate and lower resistance to flow

What part of this spectral Doppler waveform is marked by the two white arrows?

spectral window

What mechanism helps the venous system move blood from the lower extremities to the right atrium of the heart?

calf muscle pump

Accurate velocity measurements can be obtained from a blood vessel that's imaged in the transverse plane (short axis) as long as the Doppler angle is known.

False

wnat is tne proper name of the sections of this spectral Doppler waveform highlighted by the white arrows?

spike turbulence

What is considered a normal hematocrit value for a healthy female?

42%

What is another name for red blood cells?

erythrocytes

According to the lecture, what does turbulent blood flow usually indicate?

cardiovascular disease

At higher transmit frequencies Rayleigh Scatterers in the blood will create a much stronger Doppler signal, which should make blood highly echogenic. However, what factor tends to override this stronger signal

as it propagates back to the transducer?

attenuation

How accurate is dating a thrombus based solely on its sonographic B-Mode appearance?

not very accurate

What effect will polycythemia vera have on a patient's hematocrit?

increase

Which term describes scatterers that are smaller than the wavelength of the transmitted ultrasound beam?

Rayleigh

What effect will anemia have on a patient's hematocrit?

decrease

How is a scanning system's sensitivity evaluated with a test phantom?

recording the depth of the deepest target visible on the image monitor

T/F: Quality Assurance is performed by staff sonographers every day.

True

Which accrediting organization evaluates a department in a hospital or clinic to ensure compliance with current quality assurance standards?

JCAHO

How many continuing education credits are required for sonographers to maintain certification every three years?

30

Which accrediting body is responsible for standardizing the guidelines for ultrasound scanning protocols?

AIUM

Who takes on the primary, responsibility of ensuring the department is in compliance with QA?

Department Supervisor

Aorta

High pressure, high velocity, low resistance

Arterioles

Low pressure (first pressure drop), slow velocity, high resistance

Capillaries

Lower pressure, slow velocity, highest resistance

IVC

Low pressure, slow velocity, high resistance (overcome by valvestiespiration/atrial contraction)

Arteries

Low capacitance, low compliance

Veins

High capacitance, high compliance