Muscles & Mechanics of Respiration Flashcards
What structure is associated with muscles of the neck and the pharynx?
The larynx.
The larynx is associate with ______ muscles.
Intrinsic.
What is the function of intrinsic muscles in the larynx?
- Control Vocal Folds
- Open and Close Glottis.
Name the 2 cartilages found in close proximity to the vocal folds.
- Corniculate Cartilage
- Cuneiform Cartilage
When can you see the Rima Glottidis (ridges at back)?
When the Glottis is open.
How many pleural cavities do we have?
2.
What are the two pleural cavities separated by?
Mediastinum.
What does each pleural cavity hold?
A lung.
Each Pleural Cavity is lined with a serous membrane. What is this called?
The Pleura.
What is the pleura?
A thin membrane between the lung and chest wall.
The pleura consists of two layers, name these.
- Visceral Pleura (inner)
- Parietal Pleura (outer)
The pleural space contains a small amount of ______.
Fluid.
The pleural space is _____, what does this create?
Airtight, This creates a negative pressure.
What occurs when air enters the pleural space, due to spontaneous rupture or trauma?
The lung collapses while the chest wall expands.
_______ is the collapse of a lung whilst the chest wall expands.
Pneumothorax.
What lubricates the space between the parietal (outer) and visceral (inner) layers?
Pleural Fluid.
What does Boyle’s Law define?
It defines the relationship between gas pressure and volume.
What is this equation for? :
P = 1/V
Boyle’s Law.
Boyle’s Law states that in a contained gas, external _____ forces molecules ________ ________.
Pressure, Closer Together.
The movement of gas molecules can exert _____ on the _________.
Pressure, Container.
If you decrease the volume of the container, collisions occur _______ often per unit of time. What does this do?
More. Increases the presume of the gas.
What would you do to the container in order to have fewer collisions occurring hence decreasing the pressure?
Increase the volume.
Describe the movement of the ribcage during inspiration.
The ribcage moves upward and outward during inspiration.
The ribcage moves downward and inward during _________.
Expiration.
What does inspiration create in the pleural space and lungs?
It creates a more negative pressure.
Air fills the lungs until what?
Until the intrapulmonary gas pressure equals atmospheric.
In inspiration, what does the diaphragm act as?
It acts as a piston :)
Name the term to describe what happens to the diaphragm during expiration?
“Elastic” Recoil.
In what circumstance would ventilatory requirements increase?
Exercise.
When ventilatory requirements increase (eg. exercise), what are recruited?
Muscles of expiration are recruited.
What is the normal atmospheric pressure?
760 mm Hg (mm of mercury).
mm Hg is the most common method of reporting what?
Blood pressure and gas pressure.
The intrathoracic pressure is -10 mm Hg. What does intrathoracic refer to?
Between the Lung and Chest wall. Eg. the pleural space.
Air flows from an area of ______ pressure to an area of ______ pressure. What is this known as?
Higher. Lower. Diffusion.
What does a respiratory cycle consist of?
- An inspiration (inhalation)
- An expiration (expiration)
What do the chest wall, respiratory muscles and pleural space make up?
The ventilatory pump.
What are the muscles of respiration found in the chest wall?
-Mostly Intercostal Muscles
Name the bones found in the chest wall.
- Spine
- Ribs
- Sternum
What does the chest wall enable during respiration?
It enables outward expansion and inward recoil forces.
What is the main inspiratory muscle?
Diaphragm.
What separate’s the thorax from the abdomen (bottom) and the muscular chest wall (sides)?
The Diaphragm.
Name the Major Expiratory Muscles used in “active breathing”.
Internal Intercostals and abdominal muscles.
Pulmonary Ventilation causes volume changes, what does this create?
This creates changes in pressure.
The volume of the thoracic cavity changes with the expansion or contraction of the ______ _____ and ___________.
Rib Cage, Diaphragm.
The diaphragm forms the ______ of the ______ cavity.
Floor, Thoracic.
When the diaphragm is relaxed, what shape is it?
It is dome shaped.
What structure has the following origin:
- xiphoid process
- internal surface of rib cage
- coastal cartilages of last 6 ribs
- anterior surfaces of lumbar vertebrae.
The Diaphragm.
Name the insertion of the diaphragm.
The central tendon.
Describe what would happen to the volume of the thoracic cavity is the rib cage was elevated?
The volume of the thoracic cavity increases.
When the diaphragm depresses, what does this do to the volume of the thoracic cavity?
The volume of the thoracic cavity increases.
Along with the ribs, what other structure will elevate?
The sternum.
During inspiration the rib cage moves _______ and __________.
Outward, Upward.
When pressure outside and inside are _____, no air movement occurs.
Equal.
When is the pressure outside and inside equal?
At rest, prior to inhalation.
In inhalation, the pressure inside ______, so air flows ______.
Decreases, In.
In inhalation, why does the pressure inside decrease?
Because the elevation of the rib cage and contraction of the diaphragm increase the size/volume of the thoracic cavity (causing a decrease in pressure).
The air flows into the lungs when the pressure in the ______ cavity ________.
Thoracic, Decreases.
When the rib cage returns to its original position and the diaphragm relaxes, this is known as ________.
Exhalation.
How does the volume of the thoracic cavity decrease?
The rib cage returns to its original position and the diaphragm relaxes.
In exhalation what happens to the pressure and hence the air?
The pressure increases (as the volume of the thoracic cavity decreases) and the air moves out of the lungs.
The work of breathing depends on 2 major factors, Name These.
- The compliance of the lungs and chest wall
- The resistance of the airways to the smooth flow of air.
The lung is ______.
Elastic.
The lung is elastic, what way is it constantly pulling?
It is constantly pulling inward.
Due to its elasticity, the lung would collapse if it wasn’t held open by what?
If it want held open by the chest wall.
The _____ _____ is also elastic and constantly being pulled ___________ by muscles that are always under slight tension.
Chest wall, Outward.
What does the radius of the vessels of the airway establish?
The resistance to airflow.
In some conditions the diameter of the _____ & _______ restrict airflow. For example- Chronic Obstructive Pulmonary Disease.
Bronchi, Bronchioles.
What is compliance an indicator of?
Expandability.
Low compliance requires _______ _________.
Greater Force.
High Compliance requires _____ ________.
Less Force.
A number of factors affect compliance:
- _______ _______ structure of the lungs
- Level of ______ production
- Mobility of the _______ cage.
Connective Tissue
Surfactant
Thoracic.
What is surfactant?
It is an oily secretion containing phospholipids and proteins.
What does surfactant coat, and what is it’s function?
It coats alveolar surfaces and it reduces surface tension.
The _________ pressure is relative to the atmospheric pressure.
Intrapulmonary.
In what type of breathing is the difference between atmospheric pressure and intrapulmonary pressure small?
Relaxed Breathing.
During Maximum Intrapulmonary Pressure, the difference between pressure ________. Up until the _____ becomes closed off.
Increases, Glottis.
What is the pressure in the space between the parietal and visceral pleura known as?
Intrapleural pressure.
Describe the Intrapleural pressure during respiration.
It remains below atmospheric pressure throughout the respiratory cycle. (due to the relationship between the lungs and body wall).
What does Pneumothorax allow?
It allows air into the pleural cavity.
What does pneumothorax lead to?
(Atelectasis) A collapsed lung.
What is the proper name for a collapsed lung?
Atelectasis.
The respiratory cycle is cyclical changes in _______ pressure which operate the respiratory ______, aiding venous return to the ________.
Intrapleural, pump, Heart.
What is the Tidal Volume?
The amount of air moved in and out of the lungs in a single respiratory cycle.
Name the most important respiratory muscles. (Inhalation)
- The Diaphragm
- External Intercostal muscles of the ribs.
When are accessory respiratory muscles activated?
They are activated only when respiration increases significantly.
Inhalation is always ______.
ACTIVE.
__________ is passive at rest but can be active during ______ breathing.
Exhalation, Forced.
The external intercostal muscles and diaphragm are known as the ______ Respiratory Muscles.
Primary Respiratory Muscles.
What does the contraction of the diaphragm do?
It draws air into the lungs.
The _______ is responsible for 75% of air movement and the ______ ________ muscles are responsible for 25% of air movement (in normal conditions- Inhalation).
Diaphragm, External Intercostal.
What do the accessory respiratory muscles do?
Assist in elevating ribs.
The following muscles are examples of what?
- Sternocleidomastoid
- Serratus Anterior
- Pectoralis Minor
- Scalene Muscles
Accessory Respiratory Muscles.
The sternocleidomastoid and Pectoralis minor assist in what?
The elevation of the ribs.
What are the respiratory muscles used for exhalation?
Internal Intercostal muscles
Transversus Thoracis Muscles
Abdominal Muscles.
What do the internal intercostal + Transversus thoracis muscles do?
Depress the ribs.
What is the function of the abdominal muscles?
-They compress the abdomen and force the diaphragm upward.
Respiratory movements are classified by a pattern of _______ activity.
Muscle.
What does quiet breathing involve?
Active Inhalation and Passive Exhalation.
Diaphragmatic breathing or ____ breathing, is dominated by what?
Deep, Diaphragm.
What can shallow breathing also be known as?
Costal breathing.
What is costal breathing dominated by?
Rib Cage Movements.
What is dyspnoea?
Shortness of breath, producing an accelerated pattern of shallow, ineffective breathing.
_____ accompanies elevated arterial ____ and [H+].
Dyspnoea, CO2. (too much CO2)
What is “overbreathing” known as?
Hyperventilation.
What does hyperventilation lead to?
The excessive unloading of CO2. (too little CO2)
