Pulmonary Anatomy And Physiology Flashcards
Pulmonary Anatomy and Physiology
Ventilation ≠ Respiration
- Ventilation: movement of AIR into and outside the body.
- Respiration: process by which we take in O2 and throw off CO2.
Pulmonary Anatomy and Physiology
Functional movement of the thorax:
- Pump handle: anterior and superior motion of the sternum and upper rib cage.
- Bucket handle: lateral and superior motion of the ribs.
Pulmonary Anatomy and Physiology
Principal muscles of inspiration:
- DIAPHRAGM: primary muscle of inspiration.
- INTERCOSTALS: ext & int
Pulmonary Anatomy and Physiology
What are the 2 main purposes of the thorax?
- Attachment for mm of ventilation.
- Houses lungs and mediastinum
Pulmonary Anatomy and Physiology
the thorax is made up of:
- 12 thoracic Vertebrae: provide stability
-
Sternum:
- Manubrium: ribs 1 and 2
- Body: ribs 3-7
- Sternal angle: leveled with the carina and about the 5th thoracic vertebrae.
- 12 Ribs: Attachment for muscles, protection of organs.
Pulmonary Anatomy and Physiology
Movement of the thorax increases where?
Inferiorly and anteriorly, so it is more stable posteriorly and superiorly
Pulmonary Anatomy and Physiology
What is the sequence of normal breathing?
- Diaphragm: rises the abdomen.
- Abdominals: allow lateral costal expansion of the lower chest.
- Intercostals: gentle rise of the of the upper rib cage sup and ant.
Pulmonary Anatomy and Physiology
Principal muscles of INSPIRATION:
- Diaphragm: flattens over the abd cavity. Causes chest to expand laterally and lower ribs to elevate. Depends on abdominal and intercostals for optimal diaphragmatic breathing.
-
Intercostals:
- Internal: lower the ribs, decrease pressure.
- External: elevate the ribs, increase pressure.
Pulmonary Anatomy and Physiology
When internal and external intercostals contract:
Elevate the ribs
Pulmonary Anatomy and Physiology
Upward movement of upper ribs increases _________________ diameter of chest.
anterior and posterior
Pulmonary Anatomy and Physiology
Elevation of lower ribs increases ________ diameter of the chest.
longitudinal (transverse)
Pulmonary Anatomy and Physiology
This principal muscle of inspiration flattens over abd contents, and decreases intrathoracic cavity pressure:
DIAPHRAGM
Pulmonary Anatomy and Physiology
What is the amount percentage of the diaphragm’s work in breathing?
How much of the tidal volume does it provide?
60 - 70% Of the work providing 2/3 - 3/4 of the tidal volume
Pulmonary Anatomy and Physiology
3 origins of the diaphragm:
- Posterior xiphoid.
- Ant lumbar vertebrae & arcuate ligaments.
- Inner surface of costal cartilage 6 to 12.
Pulmonary Anatomy and Physiology
How does the diaphragm level changes in relation to positioning?
- Supine: higher in thorax, larger inspiratory excursion, but harder to get a deep breath.
- Sitting: lower, easier to get a deep breath.
- Sidelying: lower side is higher.
Pulmonary Anatomy and Physiology
Muscles of exhalation:
- Exhalation is passive.
- Forceful exhalation uses abdominal muscles to depress the ribs and compress abdominal contents,
Pulmonary Anatomy and Physiology
Innervation of the diaphragm:
Phrenic nerve C3 to C5
Pulmonary Anatomy and Physiology
What happens during a concentric diaphragmatic contraction?
Quiet forceful inhalation.
Pulmonary Anatomy and Physiology
What happens during a eccentric diaphragmatic contraction?
Controlled exhalation and speech.
Pulmonary Anatomy and Physiology
Function of the intercostal muscles:
Stabilize rib cage during inhalation and prevent chest wall from moving inward toward the negative pressure.
Pulmonary Anatomy and Physiology
Innervation of the intercostals muscles:
T1 to T12
Pulmonary Anatomy and Physiology
Upper chest intercostals expand the chest in which direction?
Superior and anterior
Pulmonary Anatomy and Physiology
Lower chest intercostals expand the chest in which direction?
Lateral and superior
Pulmonary Anatomy and Physiology
Eccentric contraction of the intercostals is needed for what?
-
Controlled exhalation and speech:
- Vocal folds control exhalation speed.
Pulmonary Anatomy and Physiology
What structure controls the speed of exhalation?
- Vocal folds
- Eccentric contraction of intercostals and diaphragm
Pulmonary Anatomy and Physiology
What are the functions of the abdominal muscles from a pulmonary perspective?
- Stabilize rib cage and provide visceral support.
- Provide positive pressure to help stabilize diaphragm. Prevent abdominal cavity from pushing out when diaphragm is pressing down.
- Allow for effective cough, venous return, bowel movement.
Pulmonary Anatomy and Physiology
Innervation of the abdominal muscles:
- T6 - L1
- T4 injury? Can get a breath in, but what if they need to cough?
Pulmonary Anatomy and Physiology
Paradoxical breathing:
- Inward abdominal or chest wall movement with inspiration and outward movement with exhalation.
- Weakness of diaphragm.
Pulmonary Anatomy and Physiology
ACCESSORY INSPIRATORY MUSCLES:
- Erector Spinae (T1 - S3): stabilize thorax posteriorly.
- Pectoralis (C5 - C7): stabilize ribs; assists with ant and lat chest expansion; forced exhalation when chest moves into flx.
- Serratus Anterior (C5 - C7): only inspiration muscle paired with trunk flexion; posterior expansion with fixed UE.
- Scalenes (C3 -C8): sup and ant expansion; elevate and fix upper ribs.
- SCM (C2, C3, CN XI): sup and ant expansion; elevates the sternum.
- Trapezius (C2 - C4, CN XI): superior expansion; least energy efficient accessory muscle.
Pulmonary Anatomy and Physiology
Only inspiration muscle paired with trunk flexion; posterior expansion with fixed UE.
Serratus Anterior (C5 - C7)
Pulmonary Anatomy and Physiology
Most significant stage of normal chest development:
6-12 MO, all breathing mm available
Pulmonary Anatomy and Physiology
What is the shape of the chest wall in a newborn baby?
Triangular
Pulmonary Anatomy and Physiology
How does a newborn breathes?
Diaphragmatic breather
Pulmonary Anatomy and Physiology
According to the the body’s “aluminum can” concept, the diaphragm…
is a major pressure regulator
Pulmonary Anatomy and Physiology
According to the body’s “aluminum soda can” concept, intra-abdominal pressure always
positive
flluctuates w/breathing:
- Increase w/inhalatioN
- Decrease w/exhalation
Pulmonary Anatomy and Physiology
According to the body’s “aluminum soda can” concept, intra-thoracic pressure is…
Lower to draw air in (inhalation) and higher with exhalation
Pulmonary Anatomy and Physiology
Function of the conducting airways:
filter, warm, and conduct air to the respiratory units
Pulmonary Anatomy and Physiology
Upper airways pathway:
- From nasal and oral orificies to the false vocal cords in the larynx:
- Nose
- Nasal cavity
- Pharynx
- Nasoparynx
- Oropharynx
- Laryngopharynx
- Larynx: acts as a valve and has pronating mechanism for voice production.
Pulmonary Anatomy and Physiology
acts as a valve and has pronating mechanism for voice production
Larynx
Pulmonary Anatomy and Physiology
Lower airways go from…
True vocal folds to the alveoli:
- Trachea (ciliated)
- Bronchi (ciliated)
- Bronchioles (ciliated)
- Terminal bronchioles (non-ciliated)
- Terminal respiratory units
Pulmonary Anatomy and Physiology
Right main stem bronchus is more _____________,
_____________, and _______________ than left→clinical significance?
Vertical, shorter, and wider:
aspiration (food particles more to the right).
Pulmonary Anatomy and Physiology
Where O2 gets from lung to the capillary
Alveolar capillary septum (membrane)
Pulmonary Anatomy and Physiology
Carina:
- Located in in the trachea, where it divides into right and left main stem bronchi
- right main stem bronchi is shorter, wider, and more vertical than left
Pulmonary Anatomy and Physiology
Number of orders of branching from trachea to alveolar duct
23-25
Pulmonary Anatomy and Physiology
two or more alveoli sharing a common opening.
Alveolar sac
Pulmonary Anatomy and Physiology
Function of type I alveolar cells:
main site for gas exchange
Pulmonary Anatomy and Physiology
Function of type II alveolar cells:
Secrete surfactant
Pulmonary Anatomy and Physiology
What are goblet cells and where are they located?
- Secrete mucous
- Located in bronchioles (lower airways)
Pulmonary Anatomy and Physiology
How are inhaled particles removed in the terminal bronchioles?
May be removed by macrophages
Pulmonary Anatomy and Physiology
Cilia
What it is and location?
- Move mucous at 1 cm/min
- Use ATP
- Located in upper airways (trachea), bronchioles and smaller bronchioles
Pulmonary Anatomy and Physiology
Contents of lungs hilum/hilus:
- Pulmonary vein and artery.
- Principal bronchus.
- Bronchial veins and arteries.
- Pulmonary nerve plexus.
- Lymph vessels.
Pulmonary Anatomy and Physiology
Blood supply to lungs:
left and right bronchial arteries and veins
Pulmonary Anatomy and Physiology
Innervation of the lungs
Sympathetic and parasympathetic nervous system
Pulmonary Anatomy and Physiology
In which lung is the horizontal fissure?
R lung only, separates R upper and R middle lobes
Pulmonary Anatomy and Physiology
Lung lobes:
-
Right lung: 3 lobes, oblique and horizontal fissures.
- Horizontal fissure separates RUL and RML.
- Left lung: 2 lobes, lingula, oblique fissures.
Pulmonary Anatomy and Physiology
Number of bronchopulmonary segments:
10
some text say 10 in the R and 8 on the L
Pulmonary Anatomy and Physiology
Thoracentesis:
is a procedure to remove fluid from the space between the lungs and the chest wall
Pulmonary Anatomy and Physiology
Visceral and parietal pleurae:
- Visceral: cover the lungs.
- Parietal: attached to inner surface of thoracic cavity.
Pulmonary Anatomy and Physiology
Embryonic development of lung buds occurs when?
week 4
Pulmonary Anatomy and Physiology
Development of all major elements of the lung except the gas exchange units:
pseudoglandular period: weeks 5-17
Pulmonary Anatomy and Physiology
Embryonic week when alveolar cells begin to produce surfactant, but not enough for survival
week 20
Pulmonary Anatomy and Physiology
Prematurity more difficult before __ weeks due to production of surfactant,
28
Pulmonary Anatomy and Physiology
Complete development of mature alveoli:
7 to 8 y/o
Pulmonary Anatomy and Physiology
PULMONARY SYSTEM FUNCTIONS:
- Exchange O2 and CO2 between tissues, blood, and environment.
- Regulates blood acid-base balance (PH).
- Assist with temperature homeostasis.
- Due to receiving all cardiac output: play a role in filtering and metabolizing toxic substances.
Pulmonary Anatomy and Physiology
Oxygen transport pathway:
- Inspired oxygen and quality of ambient air (FIO2).
- Airways.
- Lungs and Chest wall.
- Diffusion.
- Perfusion.
- Myocardial function.
- Peripheral circulation.
- Tissue extraction and use of oxygen.
- Return of partially desaturated blood and CO2 to the lungs.
Pulmonary Anatomy and Physiology
What is diffusion:
passage of O2 and CO2 across the capillary alveoli membrane
Pulmonary Anatomy and Physiology
Perfusion
transport dissolved and bound gases to/from lungs and cells in blood
(=how much of the blood perfused in the lungs is getting into our system)
Pulmonary Anatomy and Physiology
Respiration:
02 consumption and the cell level and production of CO2 in use of metabolic substrates.
Pulmonary Anatomy and Physiology
Inhalation account for what percentage of inspiration?
75%
Pulmonary Anatomy and Physiology
2 circulatory systems of the lungs:
- Pulmonary circulation: (Oxygen to the body) receiving deoxygenated blood from the heart and returning oxygenated to the heart.
- Bronchial circulation: (oxygen to lungs) receiving oxygenated blood via bronchial arteries from aorta.
Pulmonary Anatomy and Physiology
Bronchial circulation accounts for what percentage of the cardiac output?
1 to 2%
Pulmonary Anatomy and Physiology
An area of low V/Q will have…
lower oxygen saturation after passing the alveoli
(High perfusion of blood but low ventilation)
Pulmonary Anatomy and Physiology
An area of high V/Q will have…
low blood perfusion but high ventilation =
highly oxygen saturated blood
Pulmonary Anatomy and Physiology
What is the anatomic dead space?
Anatomic dead space is the total volume of the conducting airways from the nose or mouth down to the level of the terminal bronchioles, and is about 150 ml on the average in humans. The anatomic dead space fills with inspired air at the end of each inspiration, but this air is exhaled unchanged.
Pulmonary Anatomy and Physiology
Exchange of oxygen and carbon dioxide b/t the lungs and blood takes place by _________ across alveolar and capillary walls.
Where does this occur?
-
Diffusion:
- Movement of gas from and area of higher concentration to an area of lower concentration
-
Occurs in the respiratory membrane:
- Alveolar wall
Pulmonary Anatomy and Physiology
Normal V/Q ratio =
0.8 to 1
Pulmonary Anatomy and Physiology
V/Q ratio properties:
- Optimal gas exchange occurs with the greatest ventilation AND perfusion.
- Alveolar ventilation follows the direction of least resistance.
- Pulmonary perfusion is position dependent (gravity).
- V/Q mismatch leads to physiologic dead space:
- Normal V/Q = 0.8 to 1
- Shunt = poor ventilation
- Physiologic dead space = poor perfusion.
Pulmonary Anatomy and Physiology
The pressure exerted by each component of a gas mixture
partial pressure
Pulmonary Anatomy and Physiology
What is the atmospheric concentration of oxygen? Nitrogen? CO2?
- Nitrogen 78.6%
- Oxygen 20.8 %
- Carbon Dioxide 0.04%
Pulmonary Anatomy and Physiology
Causes of increased CO2 production:
- Fever
- Muscle exertion
- Shivering
- Metabolic processes resulting in the formation of metabolic acids
Pulmonary Anatomy and Physiology
Causes of decreased CO2 production:
hyperventilation
Pulmonary Anatomy and Physiology
What is the function of the pneumotaxic area in the pons?
- Maintains normal patterns of respiration.
- Inhibitory impulses shortens inhalation, increases RR.
Pulmonary Anatomy and Physiology
What is the function of the apneustic area in the pons?
- Impulses prolong inspiration
During apnea, there is no movement of the muscles of inhalation, and the volume of the lungs initially remains unchanged. Depending on how blocked the airways are (patency), there may or may not be a flow of gas between the lungs and the environment; gas exchange within the lungs and cellular respiration is not affected.
Pulmonary Anatomy and Physiology
What is the primary control of the respiratory center stimulation?
Tip: CO2 can diffuse through the blood-brain barrier.
CSF pH
Pulmonary Anatomy and Physiology
What is the Hering-Breuer Reflex?
The Hering–Breuer inflation reflex, named for Josef Breuer and Ewald Hering, is a reflex triggered to prevent over-inflation of the lung. Pulmonary stretch receptors present in the smooth muscle of the airways (bronchi and bronchioles) respond to excessive stretching of the lung during large inspirations
Pulmonary Anatomy and Physiology
At birth, ventilation is initiated quickly due to …
hypoxia and hypercapnia (to much CO2)
Pulmonary Anatomy and Physiology
Tidal volume (VT):
normally inhaled and exhaled air during quiet breathing, 4-7l.
Pulmonary Anatomy and Physiology
Inspiratory Reserve Volume (IRV):
additional volume of air that can be taken beyond VT, 2+L
Pulmonary Anatomy and Physiology
Expiratory Reserve Volume (ERV):
additional volume of air that can be let out beyond VT, 0.5-1 L
Pulmonary Anatomy and Physiology
Residual Volume (RV):
air that remains in the lungs after a forceful exhalation, 1-2 L.
Pulmonary Anatomy and Physiology
Minute Ventilation:
VE = VT x RR.
amount of air moved in and out in 1 min.
Pulmonary Anatomy and Physiology
Average lung can hold around
5 liters of air
Pulmonary Anatomy and Physiology
Total Lung Capacity (TLC):
max volume to which lungs can be expanded = sum of all volumes.
Pulmonary Anatomy and Physiology
Inspiratory Capacity (IC):
sum of VT and IRV.
Pulmonary Anatomy and Physiology
Functional Residual Capacity (FRC):
sum of ERV and RV. “Relaxation Volume.”
Pulmonary Anatomy and Physiology
Vital Capacity (VC):
IRV + TV + ERV, max amount of air that can be expelled following max inhalation.
Pulmonary Anatomy and Physiology
Inspiratory Vital Capacity (IVC):
max amount of air inhaled from point of max exhalation.
Pulmonary Anatomy and Physiology
Difference in pressure between alveolar and atmospheric pressure divided by airflow
Resistance to Gas Flow, a mechanical property of the lung
Increases in the lower airways.
Slow breathing = less resistance
Fast breathing = more resistance
Pulmonary Anatomy and Physiology
Do we use ALL the air we breathe in?
no:
- Anatomic Dead Space: air in the upper airways
- Physiologic Dead Space: volume of air which is inhaled that does not take part in the gas exchange, either because it (1) remains in the conducting airways, or (2) reaches alveoli that are not perfused or poorly perfuse
Pulmonary Anatomy and Physiology
What does the X axis represents in the Oxyhemoglobin Dissociation Curve?
Oxygen Partial Pressure (mmHg)
Pulmonary Anatomy and Physiology
What will cause a shift to the right in the Oxyhemoglobin Dissociation Curve?
- Exercise
- Temperature
- PH decrease
Pulmonary Anatomy and Physiology
What will cause a shift to the left in the Oxyhemoglobin Dissociation Curve?
Pulmonary Anatomy and Physiology
ABG includes:
(Arterial Blood Gas)
- pH
- PaCO2
- PaO2,
- HCO3-, BE
- Respiratory Control of pH
Pulmonary Anatomy and Physiology
CARBON DIOXIDE TRANSPORT:
- Dissolved in plasma.
- Bound to proteins.
- Bicarbonate.
- Carried by venous blood to the lungs.
- Has the biggest effect in blood PH.
Pulmonary Anatomy and Physiology
OXYGEN TRANSPORT:
- Diffusion
- O2 dissolved in plasma
- O2 bound to hemoglobin
Pulmonary Anatomy and Physiology
Optimal gas exchange occurs with the ________ ventilation AND perfusion.
greatest
Pulmonary Anatomy and Physiology
Alveolar ventilation follows the direction of…
least resistance.
Pulmonary Anatomy and Physiology
Pulmonary perfusion is _________ dependent (gravity).
position
Pulmonary Anatomy and Physiology
Shunt =
poor ventilation
Pulmonary Anatomy and Physiology
Normal V/Q is:
- 8 -1.0
- Poor ventilation – shunt
- Poor perfusion – physiologic dead space
Pulmonary Anatomy and Physiology
Inhibitory impulses to the pneumotaxic area _______ inhalation, __________ RR.
- shortens
- Increases
Pulmonary Anatomy and Physiology
Alveolar Hypoventilation:
- Occurs when less O2 is supplied and less CO2 removed from blood
- PaO2 DECREASES and PaCo2 INCREASES (excess CO2 in blood)
- Alveolar hypoventilation will cause an excess of CO2 in the blood stream resulting in Hypercapnia