Lecture 1: Cardiovascular and Pulmonary Anatomy and Physiology Flashcards
What is rate pressure product and how is it calculated?
A measure of O2 demand; HR x SBP
Humidifying inspired air is done by what portion of the upper respirartory system?
Nasal cavity
What is the function of the myocardium layer of the heart
Facilitates the pumping action of the heart
Normal breathing during inspiration is done by what two muscles
Diaphragm / external intercostals
The ribs are the weakest point for fx in the thorax, especially at which point in the ribs?
The angle
Lower rib fx more likely to break off because they’re only connected at 1 point
* more likely to cause diaphgram issues when they’re disrupted
True ribs
Vertebrochondral Ribs
Floating ribs
1-7
8-10
11,12
What happens in a sternotomy and its used for what kind of surgery
* what muscle is most infolved
Sternum is cut down the middle.
Typically utilized in heart surgery
Peck Major is most impaired by this surgery
Know: Chest tube plcacements is when theres fluid, water, blood, inflamation, or air where it shouldnt be in the chest
* can be placed in multiple different places
* Stitched in an probs stays there a while.
* Placement area will impact PT - think transfers to that side if they have a chest tube placement
* Will need to know what lvl its at to know if you can utilize a gait belt of if its going a tube
What muscle is most involved in a sternatomy?
* sternal percautions? (4)
Peck major
Abduction passed 90
No pushing
No pulling
No reaching
“Move in the tube”
W/ inspiration how do the ribs move?
Move like a bucket handle around the sternum/vertebraae
w/ inspriation is there increased or decreased intrathoracic pressure
* What are the priamry muscles of inspiration
Less pressure on the inside, so air travels down its concentration gradient and into the lungs
* theres more pressure outside in the environment than inside our lungs –> so air moves to the area of least resistance
* air is forced into the lungs
Primary muscles of inspirationa are the external intercostals and the diaphgram (flattens to contract)
* its active in inspiration and passive in expiration
What is diaphragm excursion?
How much the diaphragm moves
What is normal diaphragmatic excurison?
2-3 inches of movement w/ breathing
What is maximal ventilatory effect diaphragmatic excursion #’s?
2.5-4 inches
* so this like breathing as hard as you can
* so its forced massive breaths
What happens to diaphragmatic excursion of person has COPD?
* why would someone w/ this disorder rely more on accessory muscles
Can’t get air out but can get it in just find (you’re retaining air)
So lungs are chronically hyper inflated.
* meaning that with maximal breaths you’ll have a lower diaphragmatic excursion because its already pretty expanded and can’t expand that much more w/ ventilation
* so you won’t have much excursion (it doesnt move as much)
So remember our muscles of inspiration are our diaphragm and external intercostals. Well now we’ve taken the diaphragm out of the picture (because it doesnt have any more room to contract because its already chronically stretched/contracted) because it can’t move that much, meaning were now going to rely more on accessory muscles
Note: We use accessory muscles during forced inspiration or EX:
* SCM, scalenes, SA, rhomboids, pectoralis major and minor, trapezius, lats, and erector spinae are some examples
You’re likely to see someone w/ COPD who reports neck / back problems due to overuse of those accessory muscles. Its a good idea to test the MMT of that SCM, rhomboids, etc…
What are the muscles of expiration (2)
* active or passive?
Abdominals
Internal intercostal muscles
this is a passive process because it happens when the diaphragm relaxes
* forced expiration incorporates thsoe abdominals
Lesion at or above C4 = issues w/ breathing because the phreneic nerve that imapcts the diaphragm is disrupted
NOTE: a lesion to this area means the diaphragm cant push air out meaning they’re going to have to do forced expiration with abdominals instead of the passive expiration they would get with the diaphragm
* they are very at risk for fluid buildup/infection that leads to pnemonia in the lungs
* People who are bed ridden for a long time are also at risk for pneomina because they arent contracting their abdominals often (at least not as much as someone walking around) meaning shit can buildup in the lungs
Inspiration = external
Expiration = internal
this is showing pleural effusion. the pleural space has a fluid buildup
chest tubes would be dropped into this area
Your lungs can collapse due to this excess fluild (pneumothorax)
upper respiratory tract includes the larynx but its kind of in the middle
what is the bifurcation in the trachia called
Cernia
What is the main job of the upper respiratory tract
Humidification
* primarly done in the nasal cavity
Lower respiratory tract includes
* Tracheal bronchile tree
* goblet cells and cilia
* Acini
what do goblet cells do
Produce mucus
Cilia are what
Little hairs
What is the point of the mucociliary pathway?
So its mucus produced by the goblet cells and moved by the cilia to entrap pathogens and move them outwards to the stomach where they will die
Where does gas exchange happen
Acini
* the alveoli, alveolar sacs and ducts, and respiratory bronchioles
4 main jobs of the nasal cavity?
Air conduction
Filtration
humidification
Temp control - don’t want to breath in cold air
Knowledge check: What nerve is responsible for the contraction of the diaphragm
Phrenic nerve
Knwoledge check: Which of the following upper respiratory structures provide humidification?
Nasal cavity
R lung = 3 lobes
* Upper
* Middle
* Lower
L Lung = 2 lobes
* Upper
* Lower
When listening to lungs you need to compare side to side
* one at a time
* this will be on lab
* Want to focus on these primary areas of lung
For the R lower lobe its primarily going to be to the side and posterior
* if you have a question asking where to listen the the lower R lobe the best answer would be towards the back because theres not that much room on the lateral portion
When listening to the lungs what body position is the pt in?
Sitting
For the Lungs what does Apical mean?
Towards the top. Its like the apex of the lung essentially
For the heart what does Apical mean?
Towards the bottom, its the apex
What does basal mean in the lungs?
Toward the bottom
What does basal mean in the heart?
Towards the top (remember, the heart is flip flopped)
Knowledge check: you’re instructed to ausculate the anterior basal region of the right lung. Where would you place the bell of your stethoscope?
R lower lobe
Basal = toward bottom
NOTE: We would never listen over the scapula
If it was above the R clavicle you would be listening to the apical portion of the R lung
Bronchial trees/projections grow to specific lobes
* know what you’re draining so you can position the pt appropriately
also notice the carina
What plexus is the main NS control for respiration and ventilation?
Pulmonary plexus
Where is the respiratory contorl center? (2)
* What does it respond to a change in?
Medulla/Pons
Responds to change in CO2
* theory of yawning
A sympathetic stimulus is sent to the lungs
* What happens to the bronchus?
* What happens to the vessels?
bronchodilation
SLIGHT vasoconstriction
What happens to the bronchioles w/ a parasymapthetic stimulus?
Bronchoconstriction
What do chemoreceptors respond to a change in?
* Where are they located?
Responds to a change in O2 (hypoxemia)
Carotid/Aorta
* They’re here because the carotid leads to the brain
* Aorta leads to systemically
What do baroreceptors respond to?
* Some things that can trigger them
Stretch in arteries
This can triggered by a deviation in BP / Blood fluid
What does sarfactant production help w/
reduces tension in alveoli
* However, you need the perfect amount, not too much or too little.
What do type II pneumocytes produce?
Sarfactant
* can be impaired genetically
* can be impared by lifestyle things such as smoking
What do mast cells do?
* What two things causes an increase in mast cells?
Signal inflammation (think putting out the cones)
Smoking/Asthma = cause an increase in these
* this is because you have inflammation there
Diffusion coefficent is a # that tells u if enough O2 is going into the blood
does glottis close during inspiration or expiration?
Expiration
Where is the diaphragmatic portion of the heart
inferior, posterior surface f the heart (most R/L ventricle)
3 layers of heart tissue
* Outer most layer is anchored to what?
1) Endocardium
* Innermmost mesothelial lining of the heart, connective tissue
2) Myocardium: Middle layer consisting of muscle tissue; contractile elements
3) Pericardium: thick outer layer of the fibrous sac around the heart
* ouble walled - outer parietal and inner pericardium (epicardium)
* This layer is anchored to the diaphram
she said there really is 4 layers
Last the 3 major cornary arteries
1) Right coronary artery - right
2) Left anterior descending - anterior right
3) Circumflex - back
* Supplies LV
Left main bifurcates into LAD/Circumflex
If arterial pressure drops BF is decreased to these cardiac arteries –> less blood to myocardium
Which side of the heart is a high pressure system
L side –> has to pump systemically
Valve betweeen the R atrium and R ventricle
Tricuspid (most first)
What valve is between the R ventricle and the pulmonary artery?
Pulmonic valve
What is the only artery in the body w/ deoxygenated blood?
Pulmonary artery
What does the pulmonary connect?
RV to lungs
What valve is between the L atrium and L ventricle?
Mitral/Bicuspid valve (less last)
Is diastole or systole the filling portion?
Diastole during filling systole during pump
Ausculate means to
listen
Areas to listen to on the heart:
* Aortic area
* Pulmonary area
* The third left itnercostal space
* The tricuspid area
* The mitral area
Which part of the heart is best auscualted in the second intercostal space close to the sternum on the right of the sternum?
Aortic area (this is where the aortic valve is)
Which part of the heart is best auscualted at the second intercostal sapce to the left of the sternum?
Pulmonary area
What is best heard at the third left intercostal space?
Murmurs of both aortic and pulmonary origins are best heard here
Which part of the heart is best auscualted at the lower left sternal border, approximately the fourth to fifth intercostal space
The tricuspid area
Which part of the heart is best auscualted at the fifth left intercostal space, medial to the midclavicular line. This is also known as the point of maximal impulse (will indicate strength of heart and also how large it is - won’t be tested specifically on this)
The mitral area (apex of heart)
O2 transport
How should a pt be positioned when listening to heart
Supine
How should the pt be positioned when listening to the lungs
Sitting
Amount of O2 the heart uses
* Product of what two things?
Myocardial O2 consumption
* Product of HR and stress on the ventricle
Indirect index of O2 demand
* Product of what two things?
* What kind of person reaches higher levels?
Rate Pressure Product
HRxSBP
Healthy individuals can reach higher lvls
I think its essentially the amount of O2 the heart uses for energy which is why it can get higher in healthier individuals
What is afterload
* High afterload does what to SV
What the heart has to work against as its pushing blood out
* Hypertension/increased resistance will increase that afterload which will decrease that SV
knowledge check: during auscultation, where is the tricupid area located?
Fourth to fifth intercostal space on the lower-left sternal border
“You know that the pt has a valve insufficiency and hear the murmer in the 4th-5th intercostal space what valve is the issue”
* tricuspid valve
* this is how questions are going to be presented on the exam
Conduction system in heart
SA node –> AV node –> bundle of HIS (AC bundle) –> Purkinje Fibers (excite the RV and LV)
Cardiac cycle
1/3 = systole
2/3 = diastole
Diastole = filling
Systole = beat
EDV measured in daistole
Diastole = relaxation
* Blood flows into the RA and LA –> atrioventricular valves –> LV/RV
* SA node = deporization
* This is the P wave on an ECG
* Depoarization –> atrial contraction (last event in diastole)
* EDV and pressures record here
Systole = contraction
* Depolarization travels to AV node –> bundle of HIS –> bundle branches –> Purkinje Fibers (makes sense these cause ventricule contraction)
* Mitral valve and Tricuspid valve close (because blood is pumping systemically)
* Ventricular control - end SV
Notice how pressire drops significantly as it reaches venous circulation.
* higher pressure in the arterial side because it has to get into every cell
What regulates pressure into the capillaries?
Arterioles
Do arterioles respond to symapthetic / parasympatheic stimulation? If so which 4 hormones are used to signal
1) Epinephrine
2) Vasopressin
3) Atrial natriuretic Peptide
4) Angiotensin II
Im guessing theres others so don’t memorize this silly list
How is pulse pressure calculated?
* what is this indicative of?
SBP - DBP
~40
Indicative of mortality
how is map calcualted?
* what does it tell us about?
* What settings are these best utilized in?
* How much is needed for tissue perfusion?
* What is normal?
* What two disaeses is it utilized w/
Map = 1/3systolic + 2/3diastolic BP
tells us about the averge of blood flow and perfusion to the tissues (how much blood is actually getting there)
* tells us if theres enough blood reaching our vital organs
* we need to know this before we work with a pt, because when they start exercising those blood demands are going to be even greater
120/80 = MAP of 93
Utilized best in acute care settings
Greater than 60mmHg is needed for tissue perfusion
Normal = 70-100mmHg
Utilized incodnittions like sepsis (follows shock and your vital organs begin to shut down) and TBI
* thats because w/ these conditions they cannot regulate their BP
Knowledge check: You are treating a 16 year old who sustained head trauma and R humeral fracture from being hit while riding their bike. You would like them to use the recumbent bike.
* Why would MAP be helpful in this situation?
* How would you go about calculating MAP?
* What MAP would be appropriate for this patient to continue EX?
1) Helpful to see if organs are getting the BF they need
2) 1/3Systolic + 2/3Diastolic
3) 60 is the bare miniumum but we want 70-100
This is done before to intiate EX
* however, you would calculate this at every stage of submax testing
Blood has a certain pH, we do get arterial blod gasses from it, that give us an idea of lung function (PA student lecture on this)
Volume of blood ejected by the heart per beat
* equation?
* What 3 things affect it
Stroke volume
EDV-ESV
1) Preload - resting tension
* increases w/ EX / poor function of heart (because everything gets backed up)
2) Contractility - how hard it beats
3) Afterload - what the heart has to work against
* increase in afterload = decrease in SV (cant push it out as well)
Ejection fx is
Percentage that tells you the current function of heart
* certain surgeries need this to be at least a % to do surgery ~35-40%
* can heart tolerate ansthesia
EF = SV/EDV
* so essneitally its the percentage of the blood ejected per beat (I guess higher = better)
How easily the hearts ventricles expand
ventricular compliance
* increased compliance means they expand easily
NOTICE: preload is that resting tension in the heart before it beats
normal cardiac output
* equation
* does EX cause an increase in CO or does it stay stable?
5.5 (4-6)
CO = HRxSV
* remember, body wants homeostasis so as one increases the other decreases
CO increases w/ EX
Where is the autonomic NS controlled in the brain?
Medulla / Lower Pons
Chronoctropic effects are
timing of heart beat (heart rate)
Iontropic effects are
Contractility
What kind of chronoctorpic / inotrophic affects does the vagus n have on the heart?
Vagus nerve = parasympathetic stimulation
* Negative inotrophic (decreased contractility)
* Negative chronotropic (decreased HR)
During a sympathetic response what are the chronoctrophic / ionotrophic affects to the heart?
Sympathetic = fight or flight
* Positive inotrophic (increased contractility)
* Positive chronotrophic effects (increased HR)
Vasoconstriction systemically and vasodilation in the heart and bronchioles
These make sense
NOTE: positive and negative do not mean good or bad here, sometimes we need both
General anesthesia: this decreases the general contarctility of the heart. So if heart is already not working well and you decrease it even more, well you’re just not likely to survive this.
To show us that there are a lot more factors affecting stroke volume than HR
HR variability is influenced by less things which is why HR can shoot up quickly or drop down quickly. SV takes longer to turn on/adjust vs HR
* when we get anxious that HR just shoots straight up
CO = HR * SV
If you have significant bradycardia you’re going to have a decreased/poor cardiac output
* You’re decreasing 1 factor in the equation and the SV can’t balance it back out
Excessive tachy –> increased HR –> impaired diastolic filling because it beats to fast to fill efficeintly –> poor SV –> decreased CO
Mild tachycardia and increase cardiac output
* Increased HR * SV = +CO
If you notice the pt has bad endurance after several weeks of therapy and their HR is increased increased. Most likely that lack of endurance is cardio releated.
* follow the excessive tachycardia pathway below
Line of questioning is different in acute care
ask more yes or no questions to avoid long converstations
“are you in any pain”
Be as objective as possible
* EX: Write “patient was teary eyed” not “pt was sad”
Are these acute or chronic symptoms
Why should you take BP fast following activity
because it can drop within 15 seconds of stopping ex
Have pt in supine
Do not do this through clothing, needs to be on the skin
murmers can be normal
same slide as before. Will need to know how to palpate these ares
Normal sounds of heart
S1 and S2 (lub and dub)
Abnormal
* S4 = heard with bell before S1 (this is when you switch it to the smaller side of the stethascope) - also called an atrial gallop - denotes hyperteions / micardial hypertrophy
* S3 = Heard with bell after S2 - also called ventricular gallop - children and under 40 often have this
We do not have to diliniate between S3/S4 we just have to know when something is abnormal.
* “Does pt have a S4 sounds, yeah thats abnormal”
abnormal heart sounds / murmers may be a sign of heart failure in nonathlete
Heard with flat part of stethoscope
if you can’t find a pulse check above and below where you think it is
* there would most likely be other things indiciating a problem if there was a missing pulse
Bed –> Chair = transfer
reget levels of assistance
Asses posture w/o patient knowing you’re doing it
In the acute setting your goals are going to be more functional than something like “pt will get 160 degrees of shoulder flexion”
Scoliosis can potentially impact respiration
