Week 4 Flashcards
5 Models of Osteopathic Patient Care impact on pulmonary function
- Biomechanical
- Respiratory-Circulatory
- Neurological
- Metabolic
- Behavioral
- Structure of the rib cage can affect the viscera underneath and vice versa
- The lungs act as a pump that creates an area of low/negative pressure which encourages venous return to the right atrium of the heart. Similarly, this pump facilitates movement of lymphatic fluid up towards lymphatic trunks and ducts.
- Lungs are controlled extrinsically by sympathetic and parasympathetic inervation
- Lungs participate in Oxygen and carbon dioxide exchange, which allows for Bicarbonate buffering
- Breathing helps with adequate sleep, speaking -> expressing yourself/verbal expression, exercise, smoking habits, birth (birth delivery depends on ability to control pressures.
Muscles for breathing
- Primary
- Secondary (accessory)
- diaphragm,
- scalene, SCM, external intercostal mm.
Examples of biomechanical problems for pulmonary
- Viscera affecting lungs
- Lungs affecting viscera
- an example is obesity/increased abdominal volume can push up on the diaphragm, decreasing respiratory function
- an example is the Valsalva maneuver where increased thoracic pressure can increase abdominal pressure
How do lungs create pump for return of blood and lympathics?
As pressure changes in the thoracic cavity, other pressure changes occur as a consequence. As the diaphragm contracts during inhalation and moves downward toward the abdomen, volume of the thoracic cavity decreases and abdominal pressure increases. As the diaphragm relaxed during exhalation, lung pressure increases and the abdominal pressure decreases.
CNS innervation of lungs
- Sympathetic: come from? causes?
- Parasympathetic : come from? causes?
- Sympathetic
- Innervation comes from levels T3-5; Bronchodilation and decreased mucus secretion
- Comes from branches of the vagus nerve; Increases bronchoconstriction and mucus secretion
Immunologic purposes of lungs
Catch debris and pathogens in mucus and expel with mucociliary escalator. Also contains macrophages that will help protect against infection
Diaphragm
- borders
- movements
- type of inspiration
- how much does it move during inspiration?
- Originates at xiphoid process, the lower 6 intercostal cartilages & L1-L3. And inserts onto the central tendon.
- As it contracts it flattens, which increases the space of the thoracic cavity
- Quiet
- Moves down 1-2 spinal levels
Scalenes
- importance in movement
- Supports the cage vertically to support the movement of the diaphragm
latissimus
- importance in breathing
- Attaches at inferior ribs
- help to brace the lower ribs outwards in support, even if you don’t move your arms
Expiratory mm
- normally
- forced
- During normal there are no real drivers of exhalation–in a passive sense when you’re just breathing normally
- Forced expiration: Innermost intercostals, internal intercostal and Abdominal mm (rectus abdominus, obliques, transversus abdominus) ->
Encourage exhalation by increasing intra abdominal pressure, which pressures back up onto the thoracic cage
Compliance in the lungs
The ability to stretch
Elastic recoil
- lungs
- chest wall
- Ability to come back to its shape
- lungs want to naturally pull in so their recoil is inward
- chest wall wants to naturally go out so it has outward elactic recoil
Do the alveoli change their volume bc they’re being filled up with air or bc they’re being pulled open?
- what does this?
- what is alveoli affect on it?
- Bc they’re being pulled open
- Your chest wall wants to go out & as it goes out to its natural state it pulls the alveoli open
- As your brain ceases the inspiratory command & your mm relax then change of pressures & alveoli pull in everything & pull in chest wall
Differences in elastic recoil in inspiration and expiration for lungs and chest wall?
- Inspiration
- Expiration
- Lungs: increase in elastic recoil, Chest: decrease in elastic recoil
- Lungs: decrease in elastic recoil, Chest: increase in elastic recoil
Compare and contrast amount of different elastic recoils?
The magnitude for the 2 recoil factors for chest wall and lungs increase and decrease equally and opposite, so inward recoil to outward recoil is equal
How does inspiration occur?
Brain initiates inspiratory command, muscles of inspiration contract, outward elastic recoil starts to decrease and inward elastic recoil starts to increase, allows for passive distension of alveoli and volume increases
Interpleural pressure, what is it?
Pressure between the chest wall and the lungs
What happens to interpleural pressure as you expand alveoli volume during inspiration?
Interpleural pressure becomes more negative. So your volume is increasing, you start to distend, your interpleural pressure becomes more negative, bc you’re distension your transmural pressure increases and becomes more positive
What’s transmural pressure?
Pressure across the alveolar wall
Why does transmural pressure become more positive?
bc alveoli are expanding, and at the same time alveolar pressure is becoming more negative, so by process of pressure gradients, air moves passively down its pressure gradient (remember atmospheric pressure=0) and air flows in
Overall walk through of inspiration
Brain starts inspiratory command, inspiratory muscles contract, volume increases, interpleural pressure becomes more negative, alveoli expands, transmural pressure is increased, and alveolar pressure on the inside becomes negative, so air flows into the alveoli bc atmospheric pressure higher than alveolar pressure at this point
Expiration pathway
- Brain signals inspiratory command to stop -> muscles relax -> volume decreases -> inward elastic recoil increases and outward elastic recoil decreases -> intrapleural pressure becomes alveolar pressure become more positive -> transmural pressure less positive than that of inspiration (this happens bc alveolar distension is decreasing, volumes are decreasing, pressure in alveoli increasing and become more positive), so now air flow goes out bc pressure gradient
If lung has decreased compliance, what happens to work of breathing?
Increases
negative pressure breathing
- difference in alveoli pressure
- normal breathing
- you have a greater distension in alveoli that are closer to chest wall than those farther away from the chest wall. So every one of them helps pull each other one open
positive pressure ventilation
- ventilator that’s inducing movement
- greater distension in alveoli further away from wall than those closer to wall.
Mechanical interdependence
- If alveoli in middle collapses, it increases stress on adjacent walls and other alveoli pull and hold it open to try to prevent collapsing of that alveoli
Pulmonary surfactant
- how it relates to lungs
- if you didnt have it?? why?
- what does this do to elastic recoil?
- If you didn’t have surfactant, what would happen to elastic recoil?
- reduce surface tension, this is important for small alveoli
- small alveoli would collapse; reducing the surface tension keeps the surface tension on the different sides of the alveoli a little bit altered, reducing surface tension on those smaller ones, and prevents them from collapsing into the larger ones so that you get air flow going into all of them
- reduces it even at very high lung volumes
- It would increase
If you have an increase in elastic recoil, what happens to compliance?
It decreases
FRC
- stands for?
- what is it?
- usually?
- functional residual capacity
- amount of volume left in lungs at end of expiration
- 0