Pathophysiology of Smoking Flashcards
What is largely affected by smoking?
Mostly affects the respiratory system
Mostly affects breathing and gas exchange
What are other effects of smoking that are not directly related to the airways?
Atherosclerosis (build-up of plaque)
Cancers around the body
The entire body can be affected by smoking
How can smoking create physiological changes?
Direct physical damage to the lungs/airways
Physical accumulation of smoke-products
Inducing cellular responses
Toxic effects of chemicals in smoke
[Downstream effects of all mentioned]
What is the purpose of the lungs?
To get chemicals (i.e., oxygen but potentially anything else that is inhaled) into the body and distributed rapidly
How can the respiratory system be directly affected by smoking?
Direct damage to the lungs as of the hazardous chemicals
Accumulation of smoke products (tar, particulates, etc.) increases diffusion pathway as air cannot travel to blood efficiently–> can potentially contribute to physical blockages in the bronchioles
Can also exacerbate existing respiratory conditions such as asthma
What is the effect of tar on the bronchioles?
Tar can block the microtubules of the alveoli and cause the alveoli lining to thicken- blocks oxygen from being absorbed into the bloodstream
What occurs when you inhale smoke?
Inhaling gas and small solids/viscous liquids into the lungs
How can the airway clear itself?
Cilia
Cilia are projections from cells which push materials upwards out of the lungs
What is the effect of smoke on cilia?
Deposits from smoke cause inflammation and damage the cilia
What happens when smoke, and the relevant particulates/viscous liquids, become stuck in the mucus lining?
Will potentially accumulate
What occurs due to the cilia being damaged?
Results in the build-up of material that should be expelled, resulting in obstruction and increased risk of infection
What is significant about second hand smoking?
Depends on the scale and is not as bad but doesn’t detrimentally increase the likelihood of smoking associated risks
What is the name of a condition that the presence of smoke-products can cause?
Emphysema- reduction in the surface area of the alveoli
What can cause emphysema and other lung conditions?
Both direct damage and inflammation cause the breakdown of tissues in the lungs
How is emphysema caused?
Smoking damages the separations between alveoli
The walls within and between alveoli break down, converting the many small air sacs into a smaller number of large ones
What occurs due to emphysema?
Alveoli balloons up therefore decreasing the surface area of the alveoli
However, the alveoli contain more oxygen, therefore oxygen uptake decreases
What is bronchitis and what does it result in?
Bronchitis is inflammation of the bronchi
Directly results in an accumulation of mucus, reducing flow through the airways and a persistent cough to try to clear it
What is COPD and what is its relation with emphysema and bronchitis?
COPD stands for Chronic Obstructive Pulmonary Disorder
Bronchitis and emphysema are two common aspects of COPD
These cause difficulty in breathing, breathlessness, chronic cough, etc.
What does the body do when it is damaged?
Body repairs to seal wound quickly as to prevent excess pathogens
Won’t do it neatly as it is an emergency, so loads of extracellular matrix and messy area of cells will result in a scar
What is the effect of minor damage in relation to scarring?
There will be less scarring
What is the link between smoke particles and scarring?
Smoke particles in the lungs can contribute to development of scar tissue within the lungs, known as interstitial fibrosis
Smoking causes large scale scarring of the lungs as smoking reopens scars, leading to the tissue thickening and so causing fibrosis
Why are fibrotic lungs problematic?
In fibrotic lungs, the scar tissue replaces a lot of the lung tissue so the respiratory system has less space to function
The scar tissue takes up space and so reduces the functional lung volume which is irreversible, but symptoms may be managed by treatment and lifestyle changes
What occurs as a result of pulmonary fibrosis?
The reduced lung function results in breathlessness, low blood oxygen and various related health problems as a result
Finger clubbing is a distinctive symptom of pulmonary fibrosis
What is the relation between smoking and cancer?
Smoking contributes to lung cancer due to exposure to physical damage and carcinogenic chemicals