Week 5 Flashcards
1
Q
What is the most common white cell in the blood?
Is it a granulocyte or an agranulocyte?
A
- neutrophil
- granulocyte
2
Q
What forms platelets?
How long do platelets live for?
A
- megakaryocyte fragments
- 7 to 10 days
3
Q
What is the lifespan of a neutrophil?
A
7 hours in the blood, and then a few days in the tissue
4
Q
What is the lifespan of a lymphocyte?
A
it can live for years
5
Q
If your reticulocyte count is LOW, what type of problem is it likely?
A
production problem
6
Q
If your reticulocyte count is HIGH, what type of problem is it likely?
A
destruction problem
7
Q
What are some common reasons for an increased WBC count?
A
infection, reactive conditions, inflammation, drug effects (prednisone), and malignancies
8
Q
What lives in the intertubercular groove of the humerus?
A
the tendon of the long head of the biceps brachii
9
Q
What are the function of glenohumoral ligaments?
A
they give strength and stability to the shoulder joint
10
Q
In the posterior compartment of the arm, what is the major nerve for innervation of those muscles?
What is the common action of those muscles?
A
- radial nerve
- elbow extension
11
Q
In the anterior compartment of the arm, what is the major nerve for innervation of those muscles?
What is the common action of those muscles?
A
- musculocutaneous nerve
- elbow flexion
12
Q
Where do the heads of the biceps insert?
What joint or joints does this act on?
A
Short: goes to the coracoid process
Long: tendon runs through the intertubercular groove and into the glenoid fossa
-acts on both the shoulder and elbow
13
Q
What does the brachialis muscle do?
A
it crosses the elbow and is a strong flexor of the elbow
14
Q
Triceps:
Where do they attach at the top?
Where do they attach at the bottom?
What joint or joints does it act on?
A
- long head crosses the shoulder to attach, lateral and medial attach on the humerus below the shoulder
- all attach to the ulna at the elbow
- acts mildly on the shoulder, but strongly on the elbow
15
Q
What is the action of the supraspinatus?
What is its innervation?
A
- initiates abduction of the shoulder
- suprascapular nerve
16
Q
What are the actions of the infraspinatus and teres minor?
A
lateral rotation of the humerus at the shoulder
17
Q
What is the action of the subscapularis?
A
medial rotation of the humerus at the shoulder and some abduction of the shoulder
18
Q
What is the action of the coracobrachialis?
A
flexion and adduction of the shoulder joint
19
Q
What compartment in the arm does the musculocutaneous nerve innervate?
What muscles are these?
A
- the anterior compartment of the arm
- the biceps, coracobrachialis, and brachialis
20
Q
What compartment does the radial nerve innervate in the arm?
What muscles are there?
A
- posterior compartment of the arm
- triceps and anconeus
21
Q
What spinal nerves give rise to the brachial plexus?
What is the order of the divisions?
A
- C5-8 and T1
- roots, trunks, divisions, cords, branches (Robert Taylor Drinks Cold Beer)
22
Q
What are the names of the cords?
Why are they named this way?
A
- lateral, medial, and posterior
- they are named in regards to their position around the axillary artery
23
Q
Which cord is not part of the “M”?
A
the posterior cord
24
Q
What does the axillary nerve innervate?
A
the teres minor and deltoid
25
What innervates the deltoid?
| What is the function of the deltoid?
- the axillary nerve
- abduction of the shoulder; medial rotation and flexion of the shoulder (anterior fibers), and lateral rotation and extension of the shoulder (posterior fibers)
26
What innervates the teres minor?
the axillary nerve
27
What borders the Quadrangular Space?
| What runs through there?
- teres major, teres minor, long head of the triceps, and the humerus
- axillary nerve and posterior circumflex humeral artery
28
What borders the Triangular Space?
| What runs through there?
- teres major, humerus, and long head of the triceps
| - radial nerve and profunda brachii artery
29
What nerve does the brachial artery follow?
the median nerve
30
What nerves do NOT innervate anything in the arm?
median and ulnar nerves
31
In which compartment of the arm are the flexor muscles?
the anterior compartment
32
What muscles cause retraction of the scapula?
trapezius, rhomboid major, and rhomboid minor
33
What muscle causes external rotation of the scapula?
| What nerve innervates this muscle?
- the serratus anterior
| - the long thoracic nerve
34
What is opposition of the thumb?
| Damage to what will impair opposition of the thumb?
- touching the thumb to the other fingers
| - damage to the thenar compartment
35
What are the name changes of the subclavian artery as it travels through the upper extremity? What are the borders where it changes names?
Subclavian, past the 1st rib anteriorly becomes the axillary, past the teres major becomes the brachial, at cubital space splits into radial and ulnar
36
Where is the autonomous testing area for the ulnar nerve?
the distal part of the 5th digit on the palmar side
37
Where is the autonomous testing area for the radial nerve?
on the back of the hand near the webbing between the thumb and index finger
38
Where is the autonomous testing area for the median nerve?
the distal part of the 2nd digit on the palmar side
39
What are the nerves that go to the hand?
median, radial, and ulnar nerves
40
What nerve runs along the posterior side of the humerus in the upper arm?
the radial nerve
41
What nerves travel through the upper arm but do not innervate anything there?
the median and ulnar nerves
42
What does the superficial branch of the radial nerve do?
| What does the deep branch do?
Superficial: innervates skin for sensation
Deep: innervates muscles in the posterior compartment of the forearm and some things in the hand
43
What nerve passes through the supinator?
| Where is it going?
- the deep branch of the radial nerve
| - to the posterior compartment of the forearm
44
In the posterior compartment of the forearm, what is the common nerve?
Any exceptions?
What are the common actions of the muscles there?
- radial nerve
- no
- wrist and digit extension
45
In the anterior compartment of the forearm, what is the common nerve?
Any exceptions?
What are the common actions of the muscles there?
- median nerve
- yes, ulnar nerve innervates half of the flexor digitorum profundus and the flexor carpii ulnaris
- flexion of the wrist and fingers, with some elbow flexion
46
What nerve runs through the carpal tunnel?
| What tendons run through it?
- the median nerve
| - tendons of the superficial and deep flexors
47
What nerve controls most of the actions of the thumb?
the median nerve
48
What do the annular ligaments of the fingers do?
they hold the flexor digitorum superficialis and profundus tendons to the bones to allow flexion of the fingers
49
What do interosseous and lumbrical muscles do in the hand?
| Where do they attach?
- cause flexion of the MP joint (the 1st knuckle) and extension of the IP joints (keeping the fingers straight)
- they attach to the extensor hood
50
Where are most of the muscles located that the ulnar nerve innervates?
What are the exceptions?
- in the hand
- ulnar nerve innervates half of the flexor digitorum profundus and the flexor carpii ulnaris in the anterior compartment of the forearm
51
What ligaments provide stability during flexion and extension of the elbow?
the ulnar and radial collateral ligaments
52
What ligament allows the radius to rotate for pronation and supination of the hand?
the annular ligament of the radius
53
When the hand is pronated, what muscle causes it to supinate?
the biceps
54
What muscle's tendons run all the way to the distal bones of fingers 2-5 to cause flexion?
What joint does this act on?
- the flexor digitorum profundus
| - the distal IP joint
55
What muscle's tendons run all the way to the distal bones of fingers 2-5 to cause extension?
What joint does this act on?
- the extensor digitorum
| - the distal IP joint
56
What muscle's tendon only runs to the 2nd finger in the posterior compartment?
What is its action?
- the extensor indicis
| - extension of the 2nd finger
57
What are the superficial muscles in the forearm that all originate off of the common flexor tendon of the medial epicondyle of the humerus?
1. pronator teres
2. flexor carpii radialis
3. palmaris longus
4. flexor carpii ulnaris
5. >>>>>>>>
58
What major veins drain the forearm and hands?
| What connects them?
- cephalic vein, on the lateral side
- basilic vein, on the medial side
- connected by the median cubital vein
59
What muscle does the median nerve travel between near the median aspect of the cubital space?
the humeral and ulnar heads of the pronator teres
60
Which carpal has the strongest articulation with the radius?
the scaphoid
61
What makes the "roof" of the carpal tunnel?
the transverse carpal ligament
62
Where does the hypothenar compartment act on?
only the 5th digit
63
Where is the anatomic snuff box?
| What lives here?
- the space between the extensor pollicus longus and the extensor pollicus brevis/abductor pollicis longus
- the radial artery and the superficial branch of the radial nerve
64
How many trunks are in the brachial plexus?
| What are they called?
-3
65
How many divisions are in the brachial plexus?
What are they called?
How many of each?
- 3 anterior divisions
| - 3 posterior divisions
66
What are the terminal branches of the brachial plexus from lateral to medial?
1. musculocutaneous
2. axillary
3. radial
4. median
5. ulnar
67
What are the branches of the brachial plexus that give off sensory innervation to the arm and forearm?
Arm: medial brachial cutaneous nerve
Forearm: medial antebrachial cutaneous nerve
68
What are the ways that CO2 can be transported in the blood stream?
Which one is the most used method?*
1. can combine with a Hb molecule
2. can combine with water to make bicarbonate and a hydrogen ion****
3. in its dissolved state
69
What is the chloride shift?
bicarbonate ions can be exchanged for chloride ions by the bicarbonate/chloride exchanger
70
What is the Haldane effect?
The hydrogen ion released by the bicarb system binds Hb and decreases its affinity for O2. This releases O2 into the tissues and increases the ability of CO2 to bind Hb.
71
How does hyperventilation affect arterial PCO2?
decreases arterial PCO2
72
How does hypoventilation affect arterial PCO2?
increases arterial PCO2
73
How is a pressure of a gas related to its volume?
inversely
74
What does the amount of gas that can dissolve into a fluid depend on?
- the solubility of that gas into that fluid
- temperature of the fluid
- partial pressure of the gas
75
What is the total pressure of a gas mixture equal to?
the sums of the pressures that each gas exerts independently
76
How do you calculate the volume of air ventilated per minute (VE)?
breathing frequency x tidal volume
77
How do you calculate the amount of ambient air reaching the alveoli per minute?
breathing frequency x (tidal volume - physiological dead space)
78
What is the alveolar gas equation?
PAO2 = PIO2 - (PACO2/R) + k
79
What is the normal value for R (respiratory exchange ratio) in the alveolar gas equation?
0.8
80
How do you define alveolar ventilation?
the amount of air to get to the alveoli for gas exchange
81
How do you define minute ventilation?
the amount of air in and out of the lungs per minute, including dead space
82
What are the values for CO2 and O2 concentration inside the alveoli?
O2: 102 mmHg
CO2: 40 mmHg
83
What are the values for CO2 and O2 concentration in the returning venous blood in the lungs?
O2: 40 mmHg
CO2: 45 mmHg
84
What are the values for CO2 and O2 concentrations in inspired air?
O2: 160 mmHg
CO2: ~0 mmHg
85
What are the steps in moving air from the alveoli to tissues?
1. move O2 from alveoli to the blood plasma
2. move O2 from the plasma to Hb in RBCs
3. remove O2 from Hb and move it into working tissues
86
How does area affect diffusion rate in the lungs?
the larger the area, the higher the diffusion rate
87
What is the primary driver for O2 diffusion in the lungs?
pressure gradient
88
How does thickness of the membrane affect diffusion rate in the lungs?
the thicker the membrane, the slower the diffusion
89
What can limit the transport of CO?
ONLY something that affects its diffusion because it binds quickly to Hb so there is always a large gradient present
90
How do you calculate total oxygen concentration in the blood?
(O2 binding capacity of Hb x % saturation) + dissolved O2
91
What is the oxygen saturation of venous blood?
75%
92
What is the effect of a shift to the right of the oxygen P50 curve?
What can cause it?
- shift to the right causes unloading
| - increased PCO2, decreased pH (increase H+ concentration), increased temperature, increased 2,3BPG
93
What is the effect of a shift to the left of the oxygen P50 curve?
What can cause it?
- shift to the left causes loading
| - decreased PCO2, increased pH (decrease H+ concentration), decreased temperature, decreased 2,3BPG
94
In the respiratory system, what are the:
sensors?
controllers?
effectors?
- Sensors = chemoreceptors, lung, and others
- Controllers = mostly the medulla, but also the pons and other parts of the brain
- Effectors = respiratory muscles
95
What do the peripheral chemoreceptors sense?
| Where are they located?
- oxygen, CO2, and pH
| - the aortic and carotid areas
96
What do the central chemoreceptors sense?
| Where are they located?
- directly to pH and indirectly to CO2 (NOT O2)
| - in the brain
97
What things fine tune the inspiratory center?
the apneustic and pneumotaxic centers
98
What is another name for the Dorsal Respiratory Group?
What is it responsible for?
What does it activate?
Where is it located?
- the inspiratory center
- the basic rhythm of breathing
- the phrenic nerve and inspiratory muscles
- in the medulla oblongata
99
What is another name for the Ventral Respiratory Group?
Where is it located?
When is it active?
- the expiratory center
- in the medulla oblongata
- not during quiet breathing, but during exercise or stress
100
What is the apneustic center responsible for?
| Where is it located?
- inspiratory gasps
| - the pons
101
What is the pneumotaxic center responsible for?
| Where is it located?
- provides inhibitory impulses on inspiration to prevent overfilling of the lungs
- the pons
102
What role does the cerebral cortex play in breathing?
can override the basic rhythm of normal breathing, to a certain extent
103
What role does the hypothalamus and limbic system play in breathing?
can be activated in times of fear, anger, or excitement
104
Can H+ cross the BBB?
| Can CO2?
H+ cannot cross the BBB
| CO2 can cross the BBB
105
Can H+ cross the CSF-brain barrier
| Can CO2?
both can cross the CSF-brain barrier
106
How does the central chemoreceptor receive its signal?
1. CO2 in the capillary crosses the BBB (H+ cannot)
2. CO2 crosses the brain-CSF barrier into the CSF
3. CO2 combines with the bicarb system to produce H+ ions
4. H+ crosses the brain-CSF barrier into the medulla
5. H+ binds central chemoreceptors
107
What gets activated in the peripheral chemoreceptors?
What things can activate it?
How does activation work?
- type I glomus cells
- hypoxia, hypercapnia, and acidosis
1. inhibition of K+ channels
2. depolarization of the membrane
3. opening of votlage-gate Ca channels
4. release of neurotransmitters
5. bind to afferent nerve fibers and conduct signals
108
Where are pulmonary stretch receptors located?
What do they sense?
What do they do?
- smooth muscle layers of conducting airways
- increased stretch
- causes increased firing rate, which inhibits the inspiratory area
109
Where are the irritant receptors located?
What do they sense?
What do they do?
- in large conducting airways
- touch or noxious gases
- broncoconstriction for protection
110
Where are the juxtapulmonary capillary receptors located?
What do they sense?
What do they do?
- in alveolar walls near capillaries
- engorgement of capillaries
- increase ventilation with rapid, shallow breathing when pulmonary capillaries are pathologically engorged, such as in heart failure or pulmonary edema
111
At what point does O2 become the primary driver for respiration over CO2?
when PO2 is close to or below 60 mmHg
112
How does an increase in cardiac output affect pulmonary vascular resistance?
increases in CO lead to a decrease in PVR
113
How does increased PAP decrease PVR?
by recruitment and distension
114
At what point does the lowest PVR occur?
at the FRC
115
In the lungs, what does local hypoxia cause?
| What does this attempt to do?
- vasoconstriction to the blood vessels supplying it (opposite of the systemic capillaries)
- tries to improve V/Q matching by sending blood to better ventilated alvoeli
116
In the lungs, what happens during generalized hypoxia?
| When does this usually occur?
- substantial vasoconstriction in the lungs, leading to an increased PVR
- extreme cases of lung disease or high altitude
117
In an upright lung, where is pulmonary blood flow the greatest?
at the base
118
For zone 1 in the lung, place in order of largest to smallest the arterial pressure, alveolar pressure, and venous pressure.
```
largest = alveolar pressure
middle = arterial pressure
smallest = venous pressure
```
119
For zone 2 in the lung, place in order of largest to smallest the arterial pressure, alveolar pressure, and venous pressure.
```
largest = arterial pressure
middle = alveolar pressure
smallest = venous pressure
```
120
For zone 3 in the lung, place in order of largest to smallest the arterial pressure, alveolar pressure, and venous pressure.
```
largest = arterial pressure
middle = venous pressure
smallest = alveolar pressure
```
121
Where in the lung are most alveoli located?
zone 2
122
How much of the lung is dead space?
about 30%
123
How do you calculate PAO2?
PAO2 = PIO2 - (PACO2/R) + k
124
What is the clinical definition for hypoventilation?
PACO2 greater than 40 mmHg
125
Where in the lung is ventilation the highest?
the base of the lung
126
Where in the lung is alveolar compliance the highest?
the base of the lung
127
Where in the lung is alveolar size the highest?
the apex of the lung
128
```
What are the relative values at the apex of the lung:
blood flow
ventilation
V/Q ratio
PO2
PCO2
```
```
blood flow- very low
ventilation- low
V/Q ratio- high
PO2- high
PCO2- low
```
129
```
What are the relative values at the base of the lung:
blood flow
ventilation
V/Q ratio
PO2
PCO2
```
```
blood flow- very high
ventilation- high
V/Q ratio- low
PO2- low
PCO2- high
```
130
What is the normal A-a gradient?
around 5 to 10
131
What are the causes of hypoxemia?
1. decreases in PIO2 (such as at altitude)
2. hypoventilation (lungs healthy, ex drug OD)
3. diffusional limitations (things that affect the alveolar capillary membrane)
4. V/Q mismatch in upright lung (can be caused by COPD)
5. right to left shunt (bypass of lungs)
132
Which cause of hypoxemia does not respond to O2 therapy?
a right to left shunt
133
What is the action of the trapezius' superior, middle, and inferior fibers?
What is its innervation?
- Superior: extension of the head and neck, and upward rotation, retraction, and elevation of the scapula
- Middle: retraction of the scapula
- Inferior: upward rotation, retraction, and depression of the scapula
- Innervation: accessory nerve, CN XI
134
What is the infraspinatus innervated by?
| What is its action?
- suprascapular nerve
| - lateral rotation of the shoulder
135
What is the action of the teres major?
| What is its innervation?
- adduction, medial rotation, and extension of the shoulder
| - lower subscapular nerve
136
What is the action of the subscapularis?
| What is its innervation?
- medial rotation of the shoulder
| - upper and lower subscapular nerves
137
What is the superior trunk of the brachial plexus formed by?
The middle trunk?
The inferior trunk?
Superior: C5 and C6
Middle: C7
Inferior: C8 and T1
138
What slightly widens and deepens the glenoid cavity?
a lip of fibrocartilage called the glenoid labrum
139
What divides the arm into an anterior and posterior compartment?
an intermuscular septa
140
What are the flexors of the arm?
1. biceps brachii
2. coracobrachialis
3. brachialis
141
What are the extensors of the arm?
1. triceps brachii
| 2. anconeous
142
What is the action of the anconeous?
| What is its innervation?
- extension of the elbow
| - the radial nerve
143
What does the cubital fossa contain?
the median nerve, the brachial artery, and the tendon of the biceps brachii
144
What are the superficial flexors of the forearm?
1. pronator teres
2. flexor carpi radialis
3. palmaris longus
4. flexor carpi ulnaris
5. flexor digitorum superficialis
145
What are the deep flexors of the forearm?
1. flexor pollicis longus
2. flexor digitorum profundus
3. pronator quadratus
146
What are the superficial extensors of the forearm?
1. brachioradialis
2. extensor carpi radialis longus
3. extensor carpi radialis brevis
4. extensor digitorum
5. extensor digiti minimi
6. extensor carpi ulnaris
147
What are the deep extensors of the forearm?
1. supinator
2. abductor pollicis longus
3. extensor pollicis brevis
4. extensor pollicis longus
5. extensor indicis
148
Pronator teres:
Which compartment?
Action?
Innervation?
- superficial flexor of the forearm, anterior
- pronation of the forearm
- median nerve
149
Flexor carpi radialis:
Which compartment?
Action?
Innervation?
- superficial flexor of the forearm, anterior
- flexion and abduction of the wrist
- median nerve
150
Palmaris longus:
Which compartment?
Action?
Innervation?
- superficial flexor of the forearm, anteior
- flexion of the wrist
- median nerve
151
Flexor carpi ulnaris:
Which compartment?
Action?
Innervation?
- superficial flexor of the forearm, anterior
- flexion and adduction of the wrist
- ulnar nerve
152
Flexor digitorum superficialis:
Which compartment?
Action?
Innervation?
- superficial flexor of the forearm, anterior
- flexion of the MP joint and proximal IP joints of digits 2-5; flexion of the wrist
- median nerve
153
Flexor pollicis longus:
Which compartment?
Action?
Innervation?
- deep flexor of the forearm, anterior
- flexion of the IP, MP and carpometacarpal joints of the thumb; flexion of the wrist
- anterior interosseous nerve, a branch of the median nerve
154
Flexor digitorum profundus:
Which compartment?
Action?
Innervation?
-deep flexor of the forearm, anterior
-flexion of the distal IP, proximal IP, and MP joints of fingers 2-5; flexion of the wrist
-Lateral half: anterior interosseous nerve, a branch of the median nerve
Medial half: ulnar nerve
155
Pronator quadratus:
Which compartment?
Action?
Innervation?
- deep flexor of the forearm, anterior
- pronation of the forearm
- anterior interosseous nerve, a branch of the median nerve
156
Brachioradialis:
Which compartment?
Action?
Innervation?
- superficial extensor of the forearm, posterior
- flexion of the elbow
- radial nerve
157
Extensor carpi radialis longus:
Which compartment?
Action?
Innervation?
- superficial extensor of the forearm, posterior
- extension and abduction of the wrist; flexion of the elbow
- radial nerve
158
Extensor carpi radialis brevis:
Which compartment?
Action?
Innervation?
- superficial extensor of the forearm, posterior
- extension and abduction of the wrist
- deep branch of the radial nerve
159
Extensor digitorum:
Which compartment?
Action?
Innervation?
- superficial extensor of the forearm, posterior
- extension of the MP and IP joints of digits 2-5; extension of the wrist
- posterior interosseous nerve, a branch of the radial nerve
160
Extensor digiti minimi:
Which compartment?
Action?
Innervation?
- superficial extensor of the forearm, posterior
- extension of the MP and IP joints of the 5th digit
- posterior interosseous nerve, a branch of the radial nerve
161
Extensor carpi ulnaris:
Which compartment?
Action?
Innervation?
- superficial extensor of the forearm, posterior
- extension and adduction of the wrist
- posterior interosseous nerve, a branch of the radial nerve
162
Supinator:
Which compartment?
Action?
Innervation?
- deep extensor of the forearm, posterior
- supination of the forearm and hand
- deep branch of the radial nerve
163
Abductor pollicis longus:
Which compartment?
Action?
Innervation?
- deep extensor of the forearm, posterior
- abduction, extension, and lateral rotation of the carpometacarpal joint of the thumb; abduction and flexion of the wrist
- posterior interosseous nerve, a branch of the radial nerve
164
Extensor pollicis brevis:
Which compartment?
Action?
Innervation?
- deep extensor of the forearm, posterior
- extension of the MP and carpometacarpal joints of the thumb
- posterior interosseous nerve, a branch of the radial nerve
165
Extensor pollicis longus:
Which compartment?
Action?
Innervation?
- deep extensor of the forearm, posterior
- extension of the IP, MP, and carpometacarpal joints of the thumb
- posterior interosseous nerve, a branch of the radial nerve
166
Extensor indicis:
Which compartment?
Action?
Innervation?
- deep extensor of the forearm, posterior
- extension of the IP and MP joints of the 2nd digit (index finger); extension of the wrist
- posterior interosseous nerve, a branch of the radial ner
167
What muscles are in the thenar compartment?
1. abductor pollicis brevis
2. flexor pollicis brevis
3. opponens pollicis
168
Opponens pollicis:
Which compartment?
Action?
Innervation?
- thenar compartment
- medial rotation and flexion of the carpometacarpal joint of the thumb to allow for opposition to the other digits
- recurrent branch of the median nerve
169
What muscles are in the hypothenar compartment?
1. abductor digiti minimi
2. flexor digiti minimi brevis
3. opponens digiti minimi
170
Abductor digiti minimi:
Which compartment?
Action?
Innervation?
- hypothenar compartment
- flexion and abduction of the MP joint of digit 5
- deep branch of the ulnar nerve
171
Flexor digiti minimi brevis:
Which compartment?
Action?
Innervation?
- hypothenar compartment
- flexion of the MP joint of digit 5
- deep branch of the ulnar nerve
172
Opponens digiti minimi:
Which compartment?
Action?
Innervation?
- hypothenar compartment
- lateral rotation and flexion of the carpometacarpal joint of digit 5
- deep branch of the ulnar nerve
173
What are the major terminal branches that come off of the posterior cord?
the radial and axillary
174
What is stroke volume related to?
preload and contractility
175
What affects stroke volume?
contractility and preload
176
Why would you hear S3?
ventricular dilation
177
Why would you hear S4?
ventricular hypertrophy
