Exercise 33- Human Cardiovascular Physiology- Blood Pressure and Pulse Determinations

aortic pressure

second red line

atrial pressure

dark blue line

ECG

first heart sound

QRS

second heart sound

after T

ventricular pressure (left)

(falling blue line)

ventricular volume

(blue line)

aortic semilunar valve closes

E

aortic semilunar valve opens

B

AV and semilunar valves are closed

(.8 seconds)

AV valve closes

(1)

AV valve opens

(After E)

ventricular diastole

(G and H)

ventricular systole

purple

systole

contraction of the heart

diastole

relaxation of the heart

cardiac cycle

the sequence of events that occurs when the heart beats

When are the AV valves closed?

during ventricular systole

What event within the heart causes the AV valves to open

atrial pressure > ventricular pressure

When are the semi lunar valves closed

during the period of relaxation of the heart as a whole during atrial contraction

What event causes the semi lunar valves to open

ventricular pressure > pressure in the arteries

At what point in the cardiac cycle is the pressure in the heart the highest

ventricular systole

At what point in the cardiac cycle is the pressure in the heart the lowest

ventricular diastole

What event results in dicrotic notch

momentary increase in aortic pressure that occurs when the semi lunar valves snap shut

The length of a normal cardiac cycle

0.8 sec

The time interval of atrial systole

0.1 sec

The ventricular contraction period

0.3 sec

The quiescent period, or pause

0.4 sec

Two factors that promote movement of blood through the heart

alternate contraction and relaxation of the myocardium and opening and closing of the heart valves

The monosyllables describing the heart sounds are

lub dub

The first heart sound is a result of the closure of the

AV valves

The second heart sound is a result of the closure of the

semi lunar valves

The heart chambers that have just been filled when you hear the first sound are the

ventricles

The chambers that have just been emptied are the

atria

Immediately after the second heart sound, the ___ and ___ fill with blood

atria and ventricles

As you listened to the heart sounds during the laboratory session, what differences in pitch, length, and amplitude (loudness) of the two sounds did you observe?

First heart sound is longer, louder, and lower in pitch than the second heart sound, which is short, sharp, and high-pitched.

In order to auscultate most accurately, indicate where you would place your stethoscope for the following sounds:

closure of the tricuspid valve:

Left or right sternal border of the 5th intercostal space.

In order to auscultate most accurately, indicate where you would place your stethoscope for the following sounds:

closure of the aortic semilunar valve:

Right sternal border of the 2nd intercostal space.

In order to auscultate most accurately, indicate where you would place your stethoscope for the following sounds:

apical heartbeat:

5th intercostal space in line with the middle of the left clavicle.

Which valve is heard most clearly when the apical heartbeat is auscultated?

Mitral

how might abnormal sounds be used to diagnose heart problems?

Abnormal sounds such as swishing sounds after valvular closure or high-pitched sounds arising when blood is forced through constricted (valve) openings might indicate valvular problems.

pulse

a rhythmical throbbing of the arteries as blood is propelled through them, typically as felt in the wrists or neck.

Pulse taking procedure

Gently place 2 fingers of your other hand on this artery. Do not use your thumb, because it has its own pulse that you may feel. Count the beats for 30 seconds, and then double the result to get the number of beats per minute.

Identify the artery palpated at each of the pressure points listed: at the wrist

Radial

Identify the artery palpated at each of the pressure points listed: in front of the ear:

Temporal

Identify the artery palpated at each of the pressure points listed. on the dorsum of the foot:

Dorsalis pedis

Identify the artery palpated at each of the pressure points listed. at the side of the neck:

Carotid

When you were palpating the various pulse or pressure points, which appeared to have the greatest amplitude or tension? Why?

The carotid artery(ies) is the major artery delivering blood to the brain (against gravity) and it is closest to the heart.

Assume someone has been injured in an auto accident and is hemorrhaging badly. What pressure point would you compress on the thigh?

Femoral artery

Assume someone has been injured in an auto accident and is hemorrhaging badly. What pressure point would you compress on the calf?

Popliteal artery

Assume someone has been injured in an auto accident and is hemorrhaging badly. What pressure point would you compress

to help stop bleeding from each of the following areas?

the forearm:

Brachial artery

Assume someone has been injured in an auto accident and is hemorrhaging badly. What pressure point would you compress

to help stop bleeding from each of the following areas?

the calf:

tibial artery

How can you tell if the bleeding is arterious or venous by sight?

Color

What is the difference between an apical pulse and an arterial pulse called?

pulse deficit

blood pressure

the pressure that is exerted by the blood against the walls of blood vessels

Identify the phase of the cardiac cycle to which of the following apply? Systolic pressure

Systole (ventricular contraction)

Identify the phase of the cardiac cycle to which of the following apply? Diastolic pressure

Diastole (relaxation)

What is the name of the instrument used to compress the artery and record pressures in the auscultatory method of determining

blood pressure?

Sphygmomanometer

What are the sounds of Korotkoff?

Sounds that can be auscultated over a partially occluded artery.

What causes the systolic sound?

Sound of turbulent blood flow as it first begins to move through the constricted artery.

What causes the disappearance of the systolic sound?

Blood is flowing freely; the artery is no longer constricted.

Interpret 145/85

145 = systolic pressure; 85 = diastolic pressure reported as the point where the sound muffles

Pulse pressure

difference between systolic and diastolic pressure

Why is this measurement important?

It indicates the actual working pressure (actual amount of blood forced out of the heart during

systole).

Explain why pulse pressure is different from pulse rate?

Pulse pressure is the difference between systolic and diastolic pressure and the pulse rate is the pressure surges per minute.

How do venous pressures compare to arterial pressures? Why?

Venous pressures are lower; Veins are far removed (in the circuit) from the pumping action of the heart.

What maneuver to increase the thoracic pressure illustrates the effect of external factors on venous pressure?

Valsalva maneuver

How is Valsalva maneuver performed?

A person takes a deep breath, and mimics the motions of exhaling forcibly, but without actually exhaling. The

glottis will close and the intrathoracic pressure will increase.

What might an abnormal increase in venous pressure indicate?

Heart failure. With the heart unable to adequately pump blood, it pools in the lower extremities and increases venous pressure.

WHAT EFFECT DO THE FOLLOWING HAVE ON BLOOD PRESSURE? :INCREASED DIAMETER OF THE ARTERIOLES

DECREASES

WHAT EFFECT DO THE FOLLOWING HAVE ON BLOOD PRESSURE? :INCREASED BLOOD VISCOSITY

INCREASES

WHAT EFFECT DO THE FOLLOWING HAVE ON BLOOD PRESSURE? INCREASED CARDIAC OUTPUT

INCREASES

WHAT EFFECT DO THE FOLLOWING HAVE ON BLOOD PRESSURE? HEMORRHAGE

DECREASES

WHAT EFFECT DO THE FOLLOWING HAVE ON BLOOD PRESSURE? ARTERIOSCLEROSIS

INCREASES

WHAT EFFECT DO THE FOLLOWING HAVE ON BLOOD PRESSURE? INCREASED PULSE RATE

INCREASES

IN WHICH POSITION (SITTING, RECLINING, OR STANDING) IS THE BLOOD PRESSURE NORMALLY THE HIGHEST? THE LOWEST

HIGHEST: RECLINING LOWEST: STANDING

WHAT IMMEDIATE CHANGES IN BLOOD PRESSURE DID YOU OBSERVE WHEN THE SUBJECT STOOD UP AFTER BEING IN THE SITTING OR RECLINING POSITION?

Your blood pressure is higher when your heart is hard at work, pumping blood while your body is moving, keeping balance, etc. (when you're awake and standing.) And when you are reclining, your heart is at rest and doesn't need to work as hard to pump blood through out the bodY

WHAT CHANGES IN THE BLOOD VESSELS MIGHT ACCOUNT FOR THE CHANGE?

Blood vessels can feel the shear stress caused by blood flow. When shear stress increases the blood vessel responds and the diameter becomes larger. Thus in short, changes in blood flow might cause blood vessels to change diameter

AFTER THE SUBJECT STOOD FOR 3 MINUTES, WHAT CHANGES IN BLOOD PRESSURE WERE OBSERVED? HOW DO YOU ACCOUNT FOR THIS CHANGE?

The blood pressure evened out back to normal, took 3 minutes for blood to be distributed normally to and from the heart to body.

WHAT WAS THE EFFECT OF EXERCISE ON BLOOD PRESSURE?

During exercise systolic blood pressure (the upper reading) usually increases gradually. However, regular exercise normally causes routine resting systolic and diastolic blood pressure to decrease

WHAT WAS THE EFFECT OF EXERCISE ON PULSE RATE?

When you are working out, your body is using a lot of energy, therefore your heart has to pump faster in order to keep up with the rate of breathing. Sometimes if not enough oxygen is being delivered to each cell, lactic fermentation occurs where lactic acid is produced

DO YOU THINK THESE EFFECTS REFLECT CHANGES IN CARDIAC OUTPUT OR IN PERIPHERAL RESISTANCE?

CARDIAC OUTPUT

WHY ARE THERE NORMALLY NO SIGNIFICANT INCREASES IN DIASTOLIC PRESSURE AFTER EXERCISE?

Diastolic pressure is the pressure in the circulatory system in between heartbeats. The blood isn't at any pressure inbetween beats, whether you've just exercised or are sleeping

WHAT EFFECTS OF THE FOLLOWING DID YOU OBSERVE ON BLOOD PRESSURE IN THE LABORATORY? COLD TEMPERATURE:

INCREASES BLOOD PRESSURE

WHAT DO YOU THINK THE EFFECT OF HEAT WOULD BE? WHY?

HEAT WOULD DECREASE BLOOD PRESSURE, BECAUSE IT CAUSES YOUR BLOOD VESSELS TO DILATE (OPEN UP)

Differentiate between a hypo- and a hyperreactor relative to the cold pressor test

Hyperreactors exhibit a rise of 23 mm Hg or more in bp during the test. Hyporeactors exhibit a smaller increase or a decrease in bp

Describe normal skin skin color and appearance of veins

Skin pink; veins flat and difficult to raise

What is the importance of collateral blood supplies?

Can maintain the blood supply to an organ or body part in case the nutrient artery is occluded

Explain the mechanism by which mechanical stimulation of the skin produced a flare.

Local inflammatory response produced by the chemical mediators released by injured tissue cells

What changes occured when the subject emptied the forearm of blood (by raising the arm and making a fist) and the flow was occluded with the cuff?

Skin becomes pale and cool