Cardio- Exam 2 Flashcards
What two systems control the pH?
Respiratory and renal
If the problem is respiratory, the compensation will be ______?
Renal
If the insulin is low, _____ are being metabolized very rapidly
fats
If H are being liberated (aka being introduced), the equation moves to the ____?
Left
If you have lung disease and cannot blow off CO2, the equation moves ???
Right
If you are building up an excess of CO2, what do you need to do with bicarb?
Bicarb needs to be reabsorbed by the kidneys
When latic acid is introduced (due to 400 meter dash, etc), causes ____.
metabolic acidosis
bicarb will (increase/decrease) when you are blowing off large amount of CO2?
bicarb will decrease
By looking at this chart, how do you determine if the reason for pH imbalance is during to something metabolic?
By looking at the bicarb
What is the Henderson Hasselbach equation?
**What is magic number for bicarb?
24
What does it mean if the patient’s values do NOT fall within the blue area?
There is more than one cause of there pH imbalance
**What is the partial pressure of CO2?
40
When you are running, why do you start breathing faster?
to get rid of the excess CO2 (acid) building up in your body due to exercising
When you are metabolic alkalosis, the bicarb will be ____.
Bicarb will be HIGHER than 24
When you are metabolic acidosis, the bicarb will be ____.
Bicarb will be LESS than 24
What are the three major collections of neurons that make up the control center?
Dorsal Respiratory Group
Ventral Respiratory Group
Pneumotaxic Center
______ is responsible for causes inspiration
Dorsal respiratory Group
_____ mainly causes expiration
Ventral Respiratory Group
______ mainly controls rate and depth of breathing
Pneumotaxic center which advises the dorsal and ventral respiratory groups
Where does the dorsal respiratory group get its sensory information from?
Vagus and Glossopharyngeal nerves
______, ______, and ______ transmit sensory signals into the respiratory center from the dorsal respiratory group
Peripheral chemoreceptors
baroreceptors
several types of receptors in the lungs
When do you stop taking air in, is controlled by the _____
Pneumotaxic center
controls the “switch off” point
When the pneumotaxic sign is strong the inspiration is _____
Short (.5 seconds) and filling is slight
When the pneumotaxic sign is weak the inspiration is _____
might continue for 5 or more seconds
lungs fill with great excess of air
A strong pneumotaxxic signal can increase the rate of breathing to ______.
50 breaths per minute
A weak pneumotaxic signal may reduce the rate _____
to only 3 to 5 breaths per minute
What is the main function of Pneumotaxic center?
To limit inspiration
______ remain almost totally inactive during normal quiet respiration
Ventral group of neuron
______ do not appear to participate in the basic rhythmical oscillation that controls respiration
Ventral Group of Neurons
Where are the stretch receptors located?
in the muscular portions of the walls of the bronchi and bronchioles
How do stretch receptors transmit signals? Where are they headed?
through the vagus nerve
into the Dorsal Respiratory Group
The _____ prevents over inflation of the lungs
Hering-Breuer Inflation Reflex
When the lungs becomes overstretched, what 2 things happen? Define overstretched?
-Creates a “switch off” of the inspiratory ramp
-Also increases the rate of respiration
When TV > 1.5 (x3)
In a normal healthy human being, ____ is the limited factor
Heart, NOT lungs
When it comes to CENTRAL chemical control in the brain, ____ is more important than ____
CO2 is MORE important than O2
______ acts almost entirely on the peripheral chemoreceptors. Where are they located?
Oxygen
carotid and aortic bodies (oxygenated blood), transmit nervous signals to the respiratory centers
Where is the direct chemical control located?
in the chemosensitive area just beneath the ventral surface of the medulla
What is the role of the peripheral chemoreceptors?
to detect the partial pressure of oxygen in the body
at sea level under normal circumstances, the peripheral chemoreceptors are not doing anything. Only activated if there is a problem.-> Lungs disease due to excessive coal mining (alveolar damage) and high altitude might cause the peripheral carotid bodies to detect a lower partial pressure of oxygen in the blood
The direct chemical control is highly sensitive to ____ and _____
Blood PCO2 and Hydrogen ion
_____ is the likely primary stimulus after CO2 converts to H and bicarb ion
H
(H/CO2) crosses the blood brain barrier better
CO2 crosses better than H
When blood CO2 increases, PCO2 _____ in cerebrospinal fluid. Then what happens?
also increases
Immediate reaction with water to form H
Where are peripheral chemoreceptors located outside of the brain?
-most are located in carotid bodies
- few in the aortic bodies
What is the flow from a carotid body to the dorsal respiratory area of the medulla?
Carotid bodies -> bifurcations of the common carotid arteries - > pass through Hering’s nerves -> to the glossopharyngeal nerves -> to the dorsal respiratory area of the medulla
What is the flow from a aortic body to the dorsal respiratory area of the medulla?
Aortic bodies- > located along the arch of the aorta- > vagus nerves -> dorsal medullary respiratory area
An increase in CO2 or H also excites the chemoreceptors. Is it stronger in the brain or peripheral?
7X stronger effect in the brain
____ AND ____ are responsible for regulating ventilation in healthy humans at sea level
PCO2 and H+
T/F: You have chemoreceptors in your muscles and joints
True
What are the chemoreceptors in your muscles/joints called?
Mechano/ Metabo receptors
What is the name of the receptor that is responsible for the feeling of suffocation? or dyspnea in CHF.
J receptors
Head trauma can cause the brain to swell, which causes? How do you treat it?
swelling causes compression of the cerebral arteries
Intravenous injection of hypertonic solutions or osmotically remove some of the fluids in the brain relieving the pressure
What is Cheyne- Stoke breathing?
When you blow off to much CO2 and take in too much O2
usually heard in dying patients
Sleep apnea is caused by ??
obstruction of the upper airways
build up of CO2
When V/Q is low, what direction does the Oxygen dissociation curve shift to?
Shifts to the right
When the V/Q is high, what direction does the oxygen dissociation curve shift to?
Shifts to the left
acidity or heat, will shift the Oxygen dissociation curve to ??
Shift to the right
High altitude or base, will shift the Oxygen dissociation curve to ??
Shift to the left
shifting Right or Left, will cause more oxygen to be dumped off at the tissues?
shifting to the right
Cardiac muscles muscle contraction is longer/shorter than skeletal muscle
much longer
_____ (part of the heart) exhibits automatic rhythmical electrical discharge in the form of action potentials
SA node
______ form permeable gap junctions that allow rapid diffusion of ions
Intercalated discs
What does a functional syncytium mean?
if one heart muscle fiber contracts they all contract
What are the 2 syncytia of the heart
Atrial and ventricular
the sodium/calcium channel in skeletal muscle is (faster/slower) than heart
much faster in skeletal muscle
In cardiac muscle, the calcium/sodium channels are ____.
slow and remain open for several tenths of a second
T/F: The heart uses the same excitation contraction coupling as skeletal muscles
TRUE
**the ______ action potentials in turn act on the membranes of the _______ to cause release of calcium
T Tubule
Longitudinal sarcoplasmic tubules
____ is used to increase the strength of the heart muscle contraction
Calcium
Action potential spreads to the interior of the cardiac muscle fiber along the membranes of the ______
Transverse (T) tubules.
The Strength of contraction of cardiac muscle depends on the _____ in the extracellular fluids.
[calcium ions]
B- Adrenergic stimulation _____ in force and ____ in rate of heart muscles
Increases force of heart muscle contraction
Increase rate of contraction
Why is it important that B adrenergic stimulation increases heart rate and force?
because it allows for greater relaxation time. aka more time for the ventricles to fill with blood
How does the B Adrenergic stimulation get the heart to contract stronger?
by increasing the amount of calcium in the cell
Cyclic AMP stimulates an inactive protein kinase to become _____
active protease kinase
_____ goes throughout the cell and changes the calcium dynamics.
active protease kinase
_____ stimulates an inactive protein kinase to become active protein kinase
Cyclic AMP
_____ exists in the cardiac myocytes that is present on T -Tubules that allows the calcium to go from extracellular to intercellular
L type channel
TnI- P is what? What does it do?
Troponin I (inhibition)
delays the relaxation in contraction process, causes relaxation to be longer and a more forceful but shorter contraction
what cardiac enzyme (protein) is measured after a MI to determine damage?
looking at Troponin I levels
DHP is related to ???
blood pressure
block calcium release aka calcium channel blockers
Ryanodine receptors are responsible for??
responsible for the release of Ca2+ from intracellular stores during excitation-contraction coupling in both cardiac and skeletal muscle
Amiodarone is what class? What does it do?
Class III
Prolongs phase III of the cardiac action potential, the repolarization phase where there is normally decreased calcium permeability and increased potassium permeability
Parasympathetic stimulation of the heart does what??
decreases the heart from 100 to about 65
Parasympathetic (Vagal) stimulation does what 3 things to the heart?
- decrease rate of depolarization
- increase in AP hyperpolarization
- increase threshold for contraction, making it longer to get to threshold
The intrinsic cardiac regulation is what?
heart will pump the same amount of blood it receives
Be able to draw this
The Frank- Starling mechanism is ???
the amount of blood pumped by the heart is determined by the rate of blood flow into the heart from the veins
the heart can adapt to increasing volumes of inflowing blood
the great the heart muscle is stretched during filing, the _____ the force of contraction
greater the force of contraction
the greater the quantity of blood pumped into the aorta
T/F: The organs receive and maintain their own blood supply
True: the organ can regulate its own blood flow without the help of hormones, nervous system etc etc
define preload
loading up blood before the contraction occurs
define afterload
the amount of pressure the heart has to create to eject the blood
Things that effect preload
- muscle pump (muscle constriction)
- respiratory pump (breathing)
- moving around (dynamic work)
- venoconstriction (sympathetic NS)
Things that effect afterload
- Static work (weight lifting, standing still shoveling snow)
-Increase in amount of contraction needed to pump blood out of the heart - High SBP
-Aortic stenosis - Arteriorsclerosis
The heart can increase in size of the _____
ventricle
preload problem, does the atrium or ventricle get larger?
ventricular chamber gets larger
Would a long distance runner or weight lifter be more likely to have a LARGER left ventricle
Preload (dynamic work) runners
Eccentric hypertrophy is associated with (preload/afterload) is most commonly found in (weightlifters/runners)
preload
runner
Concentric hypertrophy is associated with (preload/afterload) is most commonly found in (weightlifters/runners)
Afterload stress
weightlifters
In eccentric contraction what is happening to the muscle?
it is getting longer when its contracting
In concentric contraction what is happening to the muscle?
muscle is getting bigger, muscle is getting shorter when stretched
Afterload is an increase in _____
Preload is an increase in ____
Muscles in the ventricle
size of ventricles itself
Heart is supplied with both _____ and _____ nerves
parasympathetic
sympathetic
The parasympathetic nerves mainly go to the ____ and _____
SA and AV nodes
few to the 2 atrium
(VERY FEW to the ventricular muscles)
vagus nerve
Sympathetic nerves mainly go to ???
all parts of the heart but lots go the ventricular muscles
What happens if the sympathetic nerve is inhibited?
decreased cardiac pumping to a moderate extent. Heart rate and strength of contraction decrease by 30%
Chronotropic
how fast your heart is beating (HR)
Ionotrophic
how hard the heart is beating
Strong stimulation of the parasympathetic nerve has what effect on the heart?
fibers in the Vagus nerves to the heart can stop the heartbeat for a few seconds
what effect does strong Vagal stimulation have on the heart?
can decrease the strength of heart muscle contraction by 20 to 30%
What is the Fick equation
Know this picture
Be able to draw this picture
