Cardio and Pulmonary Flashcards
Resting HR for trained vs. untrained
Trained person has a lower resting HR.
Stroke volume for trained vs. untrained
SV is higher for a trained person
Equation for cardiac output
HR x SV
Once SV reaches max, any increase in cardiac output is due to what
Increased HR
What does the QRS complex of the ECG represent
Ventricular Depolarization
Atrial Repolarization/relaxation
Duration of QRS complex
0.08 seconds
What does the P wave of the ECG represent
Represents atrial depolarization/contraction
What does the T wave of ECG represent?
ventricular repolarizaiton (ventricular filling takes place)
What does two R waves represent
HR
Distance represents duration of contractions
The heart responds to training stimulus just like any other muscle. T/F
True
same as skeletal muscle, except has intercalated discs
Does blood flow to hear muscle increase by more than 4 fold during max work?
Yes
How are max cardiac output and max VO2 related?
linearly related.
Diastolic BP stays the same
Systolic BP will increase
Correlated at 0.90
SV reaches max value at what % for trained vs. untrained?
SV reaches max value at about 50% VO2 max for untrained
SV reaches max value at about 70-75% VO2 max for trained
Describe why heart can be considered two separate pumps
atria and ventricles each contract together
Where do the superior and inferior vena cava return blood to
Right atrium
What kind of blood does the pulmonary vein carry?
oxygenated blood
Does the aorta contain oxygenated or deoxygenated blood?
Oxygenated, Pressure of aorta is highest
Where does the mitral valve control blood flow
btw left atrium and left ventricle
What causes a heart murmur
valve is not closing completely. will have back flow of blood from left ventricle to left atrium
What happens to SV during heart murmur
SV will decrease
What happens to HR during heart murmur
HR will increase. Heart has to work harder to keep up with O2 demand
About what percentage of females will have a mitral valve prolapse?
10-15%
What are the phases of a cardiac cycle?
Systole and diastole
What is systole
Contraction of ventricles
What is diastole
Relaxation of ventricles (filling takes place from ST segment to P wave
What happens to duration of diastole during exercise?
Decreases
What is the contractile phase of the cardiac cycle?
Systole
What is the relaxation phase of the cardiac cycle?
Diastole
Where is SA node located
Posterior wall of Right Atrium
What does the PR interval represent
Time required for depolarization wave to pass through both atria
R to R interval represents what?
one complete cardiac cycle. Contraction to contraction
Normal heart sounds are a result of vibrations of the heart valves as the ____.
Close
Pressure comparison btw Right ventricle and Left ventricle
Right is 1/6 as great as left pressure
during one minute period amount of blood entering right atrium compared to amount of blood ejected from left ventricle
Amount equal
Amount of O2 needed to lift object of same weight the same height for trained vs. untrained
Same amount of O2 needed.
Start using different systems.
Trained will recover O2 faster
Max cardiac output for trained vs. untrained
Greater in trained.
Not unusual for trained to exceed 25-30 liters per minute
Higher maximal cardiac output in relation to aerobic power
Higher max cardiac output = higher aerobic power.
Resting SV for trained vs untrained
SV is greater at rest for trained.
HR in relation to intensity for trained vs. untrained
HR is relatively slower for trained
What does an increase in a-vo2 difference during exercise mean
larger percentage of available O2 being extracted from blood as it passes through muscle beds.
Effect of training on maximal a-vo2 difference
Training enhances a-vo2 difference. Increased capillary density Increased mitochondria density increased blood volume Higher extraction level higher VO2 max Higher aerobic metabolism system effects
Resistance to blood flow during exercise
Decreases
Pulmonary circulation
blood from heart to lungs and back to heart
Peripheral circulation
blood from heart to body and back to heart
arteries
large vessels that carry blood away from heart
arterioles
small branches of arteries
Capillaries
smallest vessels. Site of gas and nutrient exchange
Veins
vessels that carry blood back to heart
Venules
small veins that carry blood to heart
Venous blood
blood returning to heart
Arterial blood
blood leaving heart and going to body/lungs
2 semilunar valves
pulmonary (R) and aortic (L)
2 atrioventricular valves
Tricuspid (R) and Bicuspid/mitral (L)
where is blood pressure highest?
aorta
Diastole for trained vs. untrained
longer for trained - slower HR
Tachycardia
Fast HR
Bradycardia
Slow HR (often training induced)
Sympathetic neve fibers
increase HR
parasympathetic nerve fibers
Decrease HR
Effect of endurance training on HR
Decreases HR
Syncytial contraction
fibers contract simultaneously
Effect of steroids on heart
Increase size of heart but must work harder because less volume
Heart has high mitochondrial density. What does this mean?
high capacity for aerobic metabolism. NO LACTIC ACID
Which chamber of heart is thickest
Left ventricle. supplies whole body with blood
Effect of HTN on SV
SV is less for NTN
Pathway of impulse transmission
SA node - AV node - Bundle of His - Purkinje fibers
Time for one cardiac cycle?
0.80 seconds
Time for cardiac cycle during exercise
Shorter than at rest (less than 0.80 seconds)
ST segment
Ventriclar repolarization
SV
amount of blood pumped per contraction
Amount of cardiac output
Men = 5 L/min Women = 4.5 L/min
Resting cardiac output trained vs. untrained
same
EDV
blood in ventricle at end of diastole
ESV
blood in ventricles at end of systole
SV equation
EDV (mL) - ESV (mL)
Ejection Fraction (EF)
ratio of available blood to pumped blood.
EF = (SV/EDV) * 100
ejection fraction and fatigue
higher ejection fraction = less fatigue
EDV, SV, HR with endurance training
Increases EDV and SV
Decreases HR
High intensity level and SV
Will actually see a decrease in SV
What will increase the flow of blood
decreased resistance and increased radius of vessel
Rate of flow is proportional to what
pressure difference btw 2 ends of vessel or btw 2 chambers
Is BP higher during diastole or systole?
systole
Increased cardiac output effect on BP
increased BP
Increased capacitance (distensibility)
Decreased BP
Typical resting BP
120/80 mm Hg
Plasma percent of blood volume
55-60% total blood volume
Plasma concentration during exercise?
may decrease in volume as much as 10% during intense physical activity
Formed elements composition of blood
make up 40-45%
RBC - 99%
WBC - 1 %
Platelets composition of blood
important for clotting
Hematocrit
percentage of total blood volume composed of formed elements
Normal WBC level
3,500-10,500
Normal Hemoglobin
Males = 13.5-17.5 Females = 12-15.5
Normal platelets
150,000 - 450,000
Concerning level for WBC
below 1000
Concerning level for hemoglobin
below 8
Concerning level for platelets
below 20,000
RBC transport O2 via what ?
hemoglobin
What is hemoglobin?
protein (globin) and iron-containing pigment (heme) necessary for binding O2
Where are RBC produced
bone marrow of long bones
Lifespan of RBC
4 months
At a high altitude what happens to concentration of hemoglobin
Higher hemoglobin - can carry more O2
Plasma volume at onset of aerobic exercise
substantial decrease in plasma volume
Chronic effect of long-term aerobic training and plasma volume
plasma volume increases 12-20%
Acute effect on weight training plasma volume
plasma volume decreases 0-22%
a-vo2 diff at rest
5mL O2 per 100 mL of blood
a-vo2 diff during exercise
increases to 15 mL O2 per 100mL of blood
Amount of O2 consumed per minute at rest
250-300 mL O2 per minute
Amount O2 consumed per minute during exercise
around 750 mL O2 per minute
Fick Equation
Oxygen delivery = blood flow x a-vO2 diff
Equation for VO2
VO2 = Q x a-vO2 diff
increase in Q or a-vO2 effect on VO2
Increases VO2 for whole body
Amount of cardiac output to skeletal muscles at rest?
15-20% of cardiac output to skeletal muscles at rest
Amount of cardiac output to skeletal muscles during maximal exercise
80-85% of cardiac output to skeletal muscles during exercise
Factors that affect redistribution of blood
parallel circuitry
vasodilation
vasoconstriction
precapillary sphincters
Vasodilation
increased radius of vessel
Vasoconstriction
Decreased radius of vessel
percentage of capillary beds inactive during rest
80-85% of capillary beds are inactive during rest. When you start doing exercise capillaries open and supply O2 to working muscles
What happens to veins during exercise
vasoconstriction
Release of norepinephrine by sympathetic nerves
causes vasoconstriction
Release of epinephrine by sympathetic nerves
Vasoconstriction (veins)
Vasodilation (arteries)
Extrinsic control of vasoconstriction/vasodilation
release of norepinephrine and epinephrine
Intrinsic control of vasoconstriction and vasodilation
autoregulation
Chemoreceptors
Carotid sinus and blood lactic acid level - send signal to brain to increase/decrease intensity
venous return is aided by what
muscle pump. Riding in airplane/car. do ankle pumps
When you breathe in what happens to pressure in chest cavity
Decreases
Equation for minute ventilation
minute ventilation = tidal volume x RR
Slowing down breathing will have what effect on tidal volume and RR
increased tidal volume and decreased RR
Respiratory path
Trachea bifurcates into L and R bronchi, then branches to bronchioles, then terminal bronchioles, then have respiratory bronchioles and alveoli
What happens to alveoli with asthma
Alveoli collapse - air trapped in alveoli
Function respiratory system
- conducts air into/out of lungs
- Exchanges gases btw air/blood
- Humidifies air - prevents damage to membranes due to drying out
- warms air - helps maintain body temp
- Filters air - mucus traps airborne particles, cilia move mucus toward oral cavity to be expelled
What is site of gas exchange for O2 and CO2
Alveoli
how many alveoli in lungs
300 million
Visceral (pulmonary) pleura
outer surface of lungs
Parietal pleura
inner suface of thoracic cavity and diaphragm
pleural fluid
lubricating fluid btw two membranes
intrapleural pressure
pressure in pleural cavity btw 2 membranes; less than atmospheric pressure
Volume and pressure when chest expands just before air rushes in
Increased volume in intrathoracic area and decreased pressure
What muscles cause intrathoracic cavity to increase
diaphragm, SCM, external intercostals
Decreased in volume intrathoracic cavity
- decreased lung volume
- Increaed intrapulmonic pressure
- Air rushes out of lungs (expiration)
Most important inspiratory muscle
Diaphragm. flattens as it contracts
Contraction of diaphragm pushes abdominal contents in what direction
forward and downward
muscles that elevate ribs
external intercostals, scalene, SCM, pectorals minor
Expiration muscle effort at rest from?
no muscular effort is needed at rest
What decreases intrathoracic cavity volume (expiration)
passive recoil of diaphragm and other muscles
Muscles pulling ribs down during expiration during exercise
internal intercostals, recuts abdominus, internal obliques of abdominal wall
Airflow equation
P1-P2/resistance
What is P1-P2
difference btw 2 areas and resistance is resistance to airflow btw 2 areas
What can increase airflow?
amplifying pressure difference btw 2 areas and decreasing resistance to airflow
What is the biggest factor affecting airflow
diameter of airway
Exercise and bronchodilation
During exercise bronchodilation decreases resistance to airflow
smoking effect on airflow
increases resistance to airflow
Tidal volume
amount of air moved per breath
Pulmonary ventilation
amount of air moved into and out of lungs in a given time period
volume of air per min equaiton
VE = VT x f.
VE = volume expired per min VT = tidal volume f = breathing freq. per min
Pulmonary ventilation trained vs. untrained
Greater in trained athletes
Pulmonary ventilation equation
Pulmonary ventilation = anatomical deadspace + alveolar ventilation
Residual volume
air left in lungs after max exhalation
Frequency/depth of breathing and exercise
- increase depth of breathing first after onset of exercise
2. if increase in depth not sufficient, rate of breathing increases
As we age or with a pathology what happens to residual volume
It increases, because trapped and cannot breathe out because recoil of alveoli is not there
During exercise what increases dynamic lung volumes?
tidal volume increases
inspiratory capacity increases
Slight decrease in dynamic lung volume with exercise
- Total lung capacity
- residual lung volume
- forced vital capacity
What decreases in dynamic lung volume with exercise
- inspiratory reserve volume
- expiratory reserve volume
- functional residual capacity
As we age what happens to tidal volume and inspiratory volume
decreases
FEV1-to-FVC ratio normal percentage
85%
FEV1-to-FVC ratio for obstructive lung disease (asthma-emphysema)
less than 70% can’t expel 3,500 mL
FEV1-to-FVC for pulmonary fibrosis (restrictive)
90%. can have poor posture
Partial Pressure
Portion of pressure due to a particular gas in a mixture
Dalton’s Law
total pressure of gas mixture = some of partial pressure of each gas
Henry’s Law
amount of gas dissolved in any fluid depends on temperature, partial pressure of gas, and solubility of gas
Oxygen diffusion
partial pressure of O2 (PO2) must be greater in alveoli than blood , and greater in blood than tissue
PO2 at sea level
159.1 mm Hg
PO2 in alveoli
105 mm Hg
PO2 in arterial blood entering the lungs
40 mm Hg
PO2 in blood leaving the lungs
100 mm Hg
PO2 in tissues
40 mm Hg
difference btw PO2 in alvoli and blood?
65 mm Hg
difference btw PO2 btw blood and tissues
60 mm Hg. provides driving force for diffusion
What vessel delivers blood to the lungs?
pulmonary artery
Blood leaves the lungs via?
pulmonary vein
Partal pressure of CO2
must be greater in the blood than the alveoli and greater in tissues than blood
PCO2 in atmospheric air
0.20 mm Hg
PCO2 in alveoli
40 mm Hg
PCO2 in arterial blood entering the lungs
46 mm Hg
PCO2 in blood leaving the lungs
40 mm Hg
PCO2 in tissues
46 mm Hg
Difference btw alveoli and blood PCO2
6 mm Hg
Difference btw blood and tissue PCO2
6 mm Hg
How long does it take for equilibration of oxygen btw alveoli air and lung capillary blood?
0.25 seconds
RBC containing hemoglobin transfer what percentage of O2
98%
oxyhemoglobin
oxygen bound to hemoglobin
Deoxyhemoglobin
hemoglobin not bound to oxygen
Do males or females have higher hemoglobin levels
males
If oxyhemoglobin level less than 93% what happens
feel sluggish
Oxyhemoglobin disassociation curve Increased temperature
Shifts curve right and decreases affinity of hemoglobin for oxygen
Oxyhemoglobin disassociatin curve decreased temperature
shifts curve to the left and increases affinity of hemoglobin for oxygen
Oxyhemoglobin disassociation curve increased acidity (DECREASED pH)
shifts curve right and decreases affinity of hemoglobin for O2
Oxyhemoglobin disassociatin curve Decreased acidity (INCREASED pH)
Shift curve left and increased affinity of hemoglobin for O2
Oxyhemoglobin disassociation curve 2,3diphosphoglycerage (2,3 DPG) Increased 2, 3 DPG
Shifts curve right and decreases affinity of hemoglobin for O2
Oxyhemoglobin disassociation curve 2, 3 DPG decreased
shifts curve to left and increases affinity of hemoglobin for O2
Carbon dioxide transport
- Dissolved in plasma (7-10%)
- Bound to hemoglobin (20%)
- Transported as bicarbonate (70%)
What happens to hemoglobin concentration during exercise
Increases anywhere from 5-10%
Each gram of Hb can combine with 1.34 mL O2 so what is Hb if full saturation achieved males. (OXYGEN CAPACITY)
16 * 1.34 = 21.4%
are males or females typically more anemic
Females
Effect of sweating on hemoconcentration
sweating increases hemoconcentration
Percent saturation equation
(O2 content of Hgb/O2 capacity of Hgb) * 100
EX. O2 capacity is 20% and amount of O2 actually combined. What is percent saturation?
50%
Obesity hyperventilation syndrome
poor breathing leads to too much carbon dioxide and too little O2
- Defect in brain’s control of breathing
- Excessive fatty -tissue weight against chest wall
Transplanted patient HR and SV compared to normal
Transpant pt. has higher HR at rest and HR increases more slowly than normal during exercise.. SV is lower
What serves as oxygen reserve at start of exercise?
myoglobin
Where is myoglobin found?
In skeletal muscle and cardiac muscle
Resting minute ventilation may vary from 10-25 breaths per min T/F
True
What is anatomical dead space
respiratory passage where no gas exchange occurs btw lungs and blood
Anatomical headspace can represent small portion total lung volume - amount less 50mL
True
What level can max min ventilation reach in well trained male athletes
180 males and 130 liters females
What effect does cigarette smoking have on airway resistance?
Increases airway resistance
If there an anticipatory rise in ventilation just prior to start of exercise
yes
What happens to the lung if it detaches from the first rib?
the lung would collapse
Min ventilation during exercise and CO2 production
increase is proportional. Min ventilation depends on CO2 produced
Rate and depth of breathing can be modified by
- Higher brain centers
- Chemoreceptors in the medulla
- Other peripheral inputs
