Respiratory Physiology - Lecture 11 Flashcards
Systemic Circulation
Carrier of blood from the heart to the body
Pulmonary Circulation
Blood carried from the heart to lungs to become oxygenated.
Upper Respiratory Tract
Nasal Cavity, Pharynx, Larynx
Warms air to body temp., Humidifies air around it, filters air, and is the sense of smell
Nasal Cavity
Junction of oral and nasal cavity, warms/cools, humidifies air, also part of digestive system
Pharynx
Vocal cords, protects the lungs, coughing and throat clearing reflexes
Larynx
Lower Respiratory Tract
Trachea, bronchus, bronchiole, alveoli
Where does gas exchange primarily occur?
Alveoli
Conductive zone
Air is being transported through these; not gas exchange. Goes from the trachea to the bronchioles
Respiratory Zone
Gas exchange occurs through the many capillaries outside the alveoli. This zone contains respiratory bronchioles and Alveoli.
Does Asthma affect the conductive zone or the respiratory zone?
Conductive zone.
What happens to the airways as air goes down them
As air passes through the airways, the airways get smaller in diameter, but it opens the air to a vast amount of branches of bronchioles.
Primary site of gas exchange, tightly networked with capillaries, and has surfactant on the wall to lower surface tension.
Alveoli
Gas Exchange
Driven by differences in pressure, “Pressure Gradient”
How gas exchange works in the lungs?
RBC in our capillaries come from the pulmonary artery where CO2 is offloaded and O2 is loaded onto the HB molecule. The RBC’s take the O2 to the heart through the pulmonary veins
Oxygen Diffusion from the Alveoli to the Blood
1) O2 in the alveoli that came from the outside air we breathed diffuses to deoxygenated blood coming from pulmonary artery
2) O2 travels to tissue and Po2 is greater in the blood
3) Partial Pressure occurs and O2 moves to tissues
4) The remaining O2 goes back to the alveoli and the pressure of O2 is more in the alveoli starting the cycle over again
Carbon Dioxide Diffusion from the Blood to the Alveoli
1) There is more CO2 in the blood than in the alveoli, so it moves down its pressure gradient.
2) The pressure of CO2 in the bloodstream is less than what’s in the tissues as the tissues are starving for O2.
3) CO2 moves from the tissues to the bloodstream (down the pressure gradient)
4)Finally, when returning to the alveoli, CO2 pressure is greater in the blood (deoxygenated) than in the alveoli.
What forms does CO2 travel in
Bicarbonate (preventing the blood from becoming too acidic), Bound to Hemoglobin, dissolved in plasma
What form does O2 travel in the blood
95% bounded to HB molecule
5% dissolves in plasma
Hemoglobin
4 binding sites for O2; millions of HB molecules
Why is having more blood cells inefficient?
Leads to sticker blood and possible clots
Pulmonary Volumes
Total Lung Capacity, Tidal Volumes, Inspiratory/Expiratory Volumes, Residual Volume
Inspiratory reserve volume
forceful inhalation of air
Tidal volume
Oscillating wave representing normal inhalation and exhalation
Expiratory Respiratory Volume
Pushing air out forcefully until you can no longer do so.
Residual Volume
The amount of air left in lungs after forcefully breathing out entirely; this is the air you can’t breathe out
Vital Capacity
Consists of Tidal, Inspiratory, and expiratory volumes; vital for life
Total Lung Capacity
Total amount of air in inspiration
3 Respiratory Disease Categories
1) Pulmonary Circulatory Disease
2) Restrictive Lung Disease
3) Obstructive Lung Disease
What does Restrictive mean in terms of the lungs?
Restricting the lungs ability to expand.
Pulmonary Embolism
Build up of a clot in the Inferior Vena Cava
Treatments for Pulmonary Embolism
Anticoagulants, Oxygen, removal of embolism, Filter blood of clots.
What are Anticoagulants?
Blood thinners; great at preventing clots.
Cystic Fibrosis
Restrictive Disease; pink tissue can expand but can’t get enough oxygen. Chest wall can’t expand.
What effects do Restrictive Lung Tissue Diseases have?
- Structure of the lung is affected.
- It feels like a tight vest which does not allow for a deep breath to be taken
How can obesity be a Restrictive Lung Disease
If Obesity in chest then it can act as restrictive
Stiff Lung caused by Pulmonary Fibrosis does not allow…?
Exchange of gases because scarring of lung tissue.
Fibrotic Lung
Lung tissue had been replaced by connective tissue
Caused by cystic fibrosis, smoking or asbestos
- Fibrotic Lung
Pulmonary Fibrosis (Caused by)?
- Caused by infections
- environmental agents like asbestos and silica
- chronic inflammation
What pulmonary fibrosis leads to
Scarring and stiffer lung tissue; exerts pressure inward on alveoli. Unrepairable
Asthma
Upper airways close off in response to an allergen; hardly get any air out with each tidal volume
Airways tighten and narrow as well as produce mucus (Asthma)
Inflammatory Response
Bronchospasm
Muscles around the airways tighten
FEV1 Test (Asthma)
Tests how fast you can get air out of system; healthy takes 1 second.
Typical Asthma Symptoms
Breathlessness, Tight Chest, Wheezing, Cough
Emergency Symptoms (Asthma)
Bluish colour to the lips and face, decreased level of alertness, difficulty breathing
Treatment Include
Relievers, Controllers, Preventers
Relievers
Quick Acting Bronchodilators
Controllers
Longer acting Anti-Inflammatory/Bronchodilators
Preventers
Inhaled Costicosteroids
Chronic Obstructive Pulmonary Disease (Group of disease that makes it very hard to breathe)
Chronic Bronchitis, Emphysema
What does Obstructive mean in terms of the lungs?
Obstructs air from going into the airways (constricts airflow; small airways)
Chronic Bronchitis is the start to COPD
Initial stage of COPD
Coughing all the time (producing mucus that obstructs and constricts airways); damages lungs
Chronic Bronchitis effects
Lung irritation –> Bronchial tubes inflamed –> Inner lining swells –> excessive, thick mucus
What happens during Chronic Bronchitis
Where is Chronic Bronchitis ranked in terms of leading cause of death
5th leading cause of death in Canada
Air flow obstruction is damaged
Other effects of Chronic Bronchitis
Symptoms of Bronchitis
Frequent cough producing mucus, mild fever, fatigue, Wheezing sounds
Acute Bronchitis Treatment
Drink plenty of fluids, rest, don’t smoke, need to wait it out if viral
Chronic Bronchitis Treatment
Quit Smoking, Bronchodilators, Steroids, Oxygen Therapy, Pulmonary Rehab
What is Emphysema?
Chronic Bronchitis that has lasted for years and causes the lung tissue to die and be replaced by Fibrotic tissue.
What get’s damaged due to Emphysema
Alveolar sacs get damaged; gas exchange gets reduced.
