Emphysema Flashcards
What is Emphysema?
Smoke in the lungs activates a part of the immune system and your body releases neutrophils and macrophages as a response.
What is Emphysema characterised for?
- The destruction of the alveoli leading to reduced surface area for gas exchange
What is a result of Emphysema?
Difficult breathing and decreased O2 supply to the body
What are Neutrophils?
First responders that arrive at the site of inflammation to engulf and destroy harmful substances
What are Macrophages?
Larger immune cells that consume debris and pathogens and help initiate further immune response
What does the continuous presence of smoke lead to?
- Chronic inflammation which causes damage to the lung tissue and the walls of the alveoli
- The breakdown of the alveoli walls leads to large less efficient air spaces and reducing the lungs ability to expel air
What do Neutrophils secrete?
They secrete an enzyme called protease which breaks down proteins
What is the name of the protease called?
Elastase
What do Elastase target? And what does that do?
- Elastin
- Provides elasticity to tissues particularly in the lungs and blood vessels.
What does Elastase help with?
By breaking down elastin, elastase can help combat infections by breaking down the structural components of pathogens
What does the overactive elastase contribute to?
The destruction of alveolar walls, impairing lung functions and reducing the surface area available for gas exchange
What is Alpha-1 Antitrypsin (A1AT)
Protein produced by the liver that serves as a protease inhibitor
What do A1AT specifically inhibit?
Action of proteolytic enzymes, particularly neutrophil elastase which is secreted by neutrophils during inflammation.
A1AT acts as a protective mechanism, what does this prevent and maintain?
Excessive tissue damage caused by neutrophil activity
Helps to maintain the integrity of luge tissue and other organs
What can a deficiency of A1AT lead to?
Lead to unchecked activity of elastase resulting in tissue damage and an increase risk of developing emphysema
What is Boyle’s Law?
As the volume of the thoracic cavity increases due to the contraction of these muscles, the pressure within the lung decrease relative to the outside atmospheric pressure
What is elastic recoil?
The lung having a natural ability to return to original size after stretched or expanded
What does effective elastic recoil ensure?
Ensure that air is expelled from the lungs helping to maintain normal breathing patterns and allowing for efficient gas exchange
When we breathe out, what happens to the nerve innervation?
The nerve innervation to the intercostals and diaphragms stop as the lungs have a natural elastic recoil that allows them to deflate again
Why is elastic recoil effective for breathing?
As it helps push air out of the lungs without requiring muscle contraction
What does the destruction of elastin lead to?
Elastic recoil resulting in difficulty exhaling and trapping air in the lungs
What happens to the Alveoli and Terminal Bronchioles?
As elastin is broken down, the alveoli and terminal bronchioles become saggy and lose their structure
What is reduced elastic recoil?
Lung cannot efficiently deflate during exhalation making it harder to expel air
There is a decrease in surface area, what does this cause?
Reduction available for gas exchange
What does the loss of elastic recoil and reduce exchange area contribute to?
Hypoxemia and hypercapnia
When there is such effort to breath out, what happens to the RV and the lungs?
RV increases
Leaves stale air in the bottom of the lungs unventilatable
What does it mean when the pt gets a barrel chest?
Air still needs to breathed out in the same volume air, the chest expands and develops into a barrel chest
What is Ventilation/Perfusion (V/Q)
A concept that describes the relationship between the amount of air reaching the alveoli (ventilation) and the flow of blood in the surrounding capillaries (perfusion)
What is a normal V/Q?
0.8 - ventilation/perfusion are closely matched to optimise oxygen and the co2 exchange
When there is a V/Q mismatch, what does this cause to the alveoli
Some of the areas of the lungs may receive adequate blood flow but not enough air
Other areas may receive air but lack sufficient blood flow
What does a low V/Q ratio mean?
Decrease ventilation relative to perfusion
What does high V/Q ration mean?
Ventilation is high but perfusion is low
What condition could be in relation to high V/Q ratio?
PE where blood flow is obstructed
What can mismatch usually lead to?
- Impaired O2 of blood
- Increased work of breathing
- Potential resp. distress
- Fatigue
How can V/Q mismatch be assessed?
- Arterial blood gas analyse to measure O2 and CO2 levels
What are some managements to improve ventilations and O2?
- Bronchodilators
- O2 therapy
- Pulmonary rehab
