Bronchus
- Branch from the trachea
- Contains cartilage and smooth muscle
Bronchiole
- Branch from bronchus
- Small tubules which terminate into alveoli
- No cartilage
- Smooth muscle
Respiratory Mucosa
Moistens the air coming in to prevent dehydration of lungs and trap incoming foreign particles with help of hair
Muscociliar Escalator
- Cilia moves the mucous with anything that gets stuck in there
- Muscociliary escalator is used for debris removal (smoke)
Effect of smoking on respiratory cilia
- Smoking destroys the cilia in the airway and paralyzes the cilia
Smoking a single cigarette has an effect on cilia for how long?
- One hour or longer
What chemical in tobacco smoke destroys ciliated respiratory cells?
- Cyanide
Function of Alveoli
- Gas exchange
- Produce surfactant
- Elastic tissue
Ventilation
- Air moves between the atmosphere and the lungs in response to pressure gradients
- Air moves into lungs when pressure in atmosphere is greater than pressure in lungs
Air move out of the lungs when pressure in lungs is greater than pressure in atmosphere
Greatest single preventable cause of disease, disability, and death in our society
- Smoking, tobacco use
What causes newborn respiratory distress syndrome?
- Absence of surfactant
- Alveoli stick together and cannot expand to exchange gases
Chronic Obstructive Pulmonary Disease
- Lung disease that makes it hard to breathe, it is caused by damage to the lungs over many years, usually from smoking
- Usually a combination of asthma, chronic bronchitis, emphysema
Asthma
- Chronic inflammatory disorder to the airways associated with airway hyperresponsiveness that leads to recurrent episodes of wheezing, breathless, chest tightness and cough.
- Most common respiratory illness of children
Pathology that occurs with asthma
- Allergic reaction to airborne allergens (pollen, dust)
- Intense constriction of bronchial muscles
- Airway inflammation (produces more mucus)
Causes of Asthma
- Extrinsic: Exposure to extrinsic antigen (outside), Genetic pre-disposition
- Intrinsic: Non-immune mechanics (aspirin, lung infections, stress, exercise, cold weather)
Cause of death in asthma
- Suffocation (lungs plugged with mucus - can't exhale)
Chronic Bronchitis
- Cough for 2 consecutive years
- Spatum production for 3 months
- May occur with asthma
Chronic Bronchitis Symptoms
- Inflammation of the mucous membrane of the bronchi which results in production of excess mucus
- Deep cough
- Loss of cilia
Causes of Chronic Bronchitis
- 90% are smokers
- Grain, cotton, and silica dust
Emphysema
- Lung disease that blocks airflow and makes it hard to breathe
- Destruction of alveoli walls
- No fibrosis (scarring)
- Results in reduction in the surface area available for gas exchange
- Increase in dead air space in lungs
Symptoms of Emphysema
- Gasping for breath
- Cause: smoking
Pathology of emphysema
- Lungs lose elasticity and air is trapped in them
- As the dead air spaces increase, adequate ventilation requires more forceful inhalation
- Cannot be cured
Silicosis
- Most common chronic occupational disease in the world
- Caused by silica dust
Pneumonia
- Inflammation of the lung in which fluid accumulates in the alveoli
- Reduces gas exchange
- Bronchioles swell and narrow making it difficult to breath
- Caused by bacterial or viral infection
Main cause of lung cancer
- 90% caused by smoking
Exposure to what other environmental factors causes lung cancer?
- Tobacco (or any smoke)
- Radon
- Uranium (occupational)
- Ionizing radiation
- Asbestos
Screening recommendation for lung cancer
- No organization recommends routine screening for lung cancer because it does not affect outcome
- There are emerging recommendations
Mesothelioma
- Cancer of the pleura of the lung
What causes mesothelioma?
- 100% due to asbestos exposure
What 2 effects of nicotine have caused tobacco to be popular for thousands of years?
1. Stimulant (adrenaline)
2. Opiate effect (endorphins)
Define cigarette
- Tobacco rolled in paper
- 20 cigarettes per pack
Effect of filtered cigarettes
- Less nicotine with each inhale
- Need to smoke more for same nicotine
- Tend to inhale deeper -- cancers deeper in lungs
Define Cigar
- Tobacco rolled in tobacco
Smoke in one cigar is equal to how many cigarettes
- 1 pack of cigarettes
What type of cancer occurs most with cigar smoking?
- Oral and pharynx cancer because smoke is not inhaled, but stays in the mouth area
3 ways tobacco products can cause disease in the body
1. Direct contact with mucosa (mouth, pharynx, lungs)
2. Dissolves in saliva (mouth, pharynx, esophagus)
3. Absorbed through lung alveoli (kidney, bladder, pancreas)
3 major components of tobacco smoke
1. Nicotine
- Poisonous alkaloid found in tobacco plant
- Stimulant
- Not a carcinogen
- Not a teratogen
2. Tars
- All particulate matter except for water and nicotine
3. Gases
- Four main gases in tobacco smoke (carbon monoxide, hydrogen cyanide, ammonia
What happens to the damaged lung when someone stops smoking?
- Remains black and damaged
Principle psychoactive ingredient in marijuana
- THC
- not a carcinogen
- not a teratogen
Long-term effect of marijuana smoke on the lungs
- Residual materials from the smoke
Medical risks for smoking marijuana
- Respiratory problems
- Addiction
- Anxiety, depression, suicidal ideation, schizophrenia
- Increased heart rate by 20-100 percent
- Heart attack risk
Effects of marijuana on male reproductive system
- Lower levels of sex hormone testosterone and produce fewer sperm
Effects of marijuana on female reproductive system
- Unclear
- THC interferes with ovulation in female monkeys