Lecture 21 - When things go wrong in the respiratory system Flashcards
Three types of respiratory disease
Obstruction - airway resistance increased, outflow pressure decreased (elastic recoil lost)
Restriction - reduced compliance (lower vital capacity)
Infection and inflammation
COPD: what is it and what are its main causes?
Chronic obstructive pulmonary diseases - block the airways in a fatal manner - residual volume is increased due to decreased gas transport
Chronic bronchitis (narrowing), emphysema (recoil)
Chronic bronchitis: what are the two types, how long does each last, what causes each form, how many people have it, and what are the treatments?
Acute bronchitis and chronic bronchitis
A - days/weeks
C - 3 months/2 years
A - bacteria/virus
C - 80% due to smoking, also caused by irritants, inflammation, abnormal mucus secretion, airway plugged, increases infection likelihood, inflammation, etc
~20% of adult male
Stop smoking, bronchodilators, and/or antibiotics
Emphysema: what is it, how does it occur, how long does it last, what causes it, how many people have it, and what are the treatments?
When the alveoli walls are damaged over time, leading to larger, less efficient sacs for gas exchange, compliance, RV, and FRC increase due to overinflated lungs
Smoking causes neutrophils and macrophages to release elastase to be produced, which is controlled by the α1-antitrypsin gene but, when someone smokes in conjunction with an α1-antitrypsin deficiency, too much elastase is produced which breaks down alveoli
Lasts indefinitely
~3 million in the US
Stop smoking, given oxygen, lung transplant, given enzyme supplements that should be produced by the α1-antitrypsin gene
Asthma: what is it, how does it occur, how long does it last, what causes it, how many people have it, and what are the treatments?
Increased airway resistance due to bronchoconstriction, excess mucus production, and oedema of airway mucous
Mast cells are activated by stimulants, causing histamines and cytokines to be produced which cause oedema, smooth muscle contraction, and bronchoconstriction
Lifelong illness
Hypersensitivity reaction to allergens, air pollution, exercise and cold air, emotional stress, potentially genetics
~5.4 million in the UK
Bronchodilators (salbutamol) and anti-inflammatories
Fibrosis: what is it, what occurs, how long does it last, what are the causes, and what are the treatments?
The growth of excess connective tissue
Alveoli are replaced by connective tissue, causing increased compliance in the lungs
Lifetime
Inhaled environmental and occupational pollutants, cigarette smoke, or autoimmune disease
No effective treatments
Main restrictive lung diseases: what are they?
Fibrosis
Respiratory distress syndromes (IRDS, ARDS, SARS, etc)
Respiratory distress syndromes: what is it, what occurs, how long does it last, what are the causes, and what are the treatments?
Alveolar walls become rigid
Caused (A) by sepsis/extreme trauma, causing protein exudation, causing oedema
Caused (C) by industrial dust, drugs, or rheumatism which inflames the lungs and causes fibrosis
~ 1/25,000 people
Supportive oxygen therapy
Respiratory tract infections, what are they and how common and severe are they?
Infections in either the upper respiratory tract (NPL) or the lower respiratory tract (TBA)
Upper tract: less severe but more common
Lower tract: more severe but less common
Pneumonia what is it, what occurs, how long does it last, how many people suffer from it, what are the causes, and what are the treatments?
Illness when alveoli are filled by inflammatory exudate and the lungs become firm and airless
A couple of weeks
~1 million people each year in the US
Caused by bacteria
Antibiotics
Tuberculosis what is it, what occurs, how long does it last, what are the causes, and what are the treatments?
Latent – asymptomatic, non-infectious, granuloma (small area of inflammation) in lung tissue
Active (~10%) - spreads to bronchioles and circulation
Lymph leaks into the bronchi as infection is fought
~10 million active cases
Caused by inhaling Mycobacterium tuberculosis
Difficult due to antibacterial resistance
SARS: what is it and what is an example of this?
Severe acute respiratory syndrome
Covid-19
Covid-19: what is it and how is it transferred?
An airborne virus that seems to target lung epithelial cells and fuse with them
Believed to have a zoonotic origin and is transferred through coughing/sneezing
Systemic disorders (research these??)
Fever, cough, fatigue, headache, sputum production, haemoptysis, acute cardiac injury, hypoxemia, dyspnea, lymphopenia, and diarrhoeia
Respiratory disorders (research these??)
Rhinorrhoea, sneezing, sore throat, pneumonia ground-glass opacities, RNAaemia, and ARDS
