Week 4 Flashcards
(73 cards)
Asthma
Asthma can be defined as “a heterogeneous disease [meaning that it varies considerably for different people], and is it characterised by chronic airway inflammation. It is defined by the history of respiratory symptoms such as wheeze, shortness of breath, chest tightness and cough that vary over time and in intensity, together with variable expiratory airflow limitation”
Pathophysiology- asthma
The key pathophysiological concepts of asthma include:
○ airway inflammation (swollen lining)
○ airway hyperresponsiveness (muscle tightening)
○ mucus hypersecretion (excess mucus)
This results in airflow obstruction and then leads to clinical manifestations such as dyspnoea, cough, chest tightness, and wheeze.
Asthma Trigger- Allergen inhalation
- Animal hair (e.g. cats, mice)
- House dust mite
- Cockroaches
- Pollens
- Moulds
Asthma Trigger- Air pollutants
- Exhaust fumes
- Perfumes
Asthma Trigger- Oxidants
- Sulfur dioxides
- Cigarette smoke
- Aerosol sprays
Asthma Trigger- Inflammation and infection
- Viral upper respiratory tract infection
- Sinusitis, allergic rhinitis
Asthma Trigger- Medications
- Aspirin
- Non-steroidal anti-inflammatory agents (NSAIDs)
- β-Adrenergic blockers
Asthma Trigger- Occupational exposure
- Agriculture, farming
- Paints, solvents
- Laundry detergents
- Metal salts
- Wood and vegetable dusts
- Industrial chemicals and plastics
- Pharmaceutical agents
Asthma Trigger- Food additives
- Sulfites (bisulfites and disodium metabisulfite)
- Beer, wine, dried frui, shellfish, processed potatoes
- Monosodium glutamate
- Tartrazine
Asthma Trigger- Other factors
- Exercise and cold, dry air
- Stress
- Hormones, menses
- Gastro-oesophageal reflux disease (GORD)
Key Clinical Manifestations- Asthma
Wheeze, dyspnea, chest tightness, coughing, hypertension, tachycardia, and hypoxaemia symptoms are common symptoms of asthma. These include high-pitched, musical sounds produced by rapid vibration of bronchial walls, difficulty breathing, chest tightness, and coughing. As the asthma attack progresses, symptoms like anxiety and restlessness may become more evident.
Chronic Obstructive Pulmonary Disease (COPD)
Chronic Obstructive Pulmonary Disease (COPD) is the term given for progressive, chronic lung disease, characterised by irreversible obstruction of the airways
COPD is:
○ Preventable and treatable
○ Airflow limitation is not fully reversible
Chronic Bronchitis
Chronic bronchitis is a condition characterized by mucus hypersecretion and productive cough for over three months annually, resulting from cigarette smoking and harmful particle inhalation. This inflammation causes bronchial oedema, increased goblet cells, thick mucus production, and eventually narrowed airways.
Emphysema
○ Destruction of alveolar space (which destroys portions of the pulmonary capillary bed and increases the volume of air in the alveoli
○ Alveolar destruction –> large air spaces in lung tissue and air spaces
○ The air spaces are then not able to participate effectively in gas exchange.
○ Expiration is challenged due to a loss of elastic recoil.
○ This reduces the volume of air that is expired, and air becomes trapped in lungs
○ Air trapping –> increases chest expansion
○ Causing reduced gas exchange, increased work of breathing, hypoventilation, and hypercapnia
Clinical Manifestations- Asthma
- Persistent cough
- Dyspnoea
- Recurrent or severe pulmonary infection
- Barrel chest
- Digital clubbing
- Fatigue
Over time clinical manifestations and symptoms of COPD can worsen and may include - Haemoptysis
- Pneumothorax
COMMUNITY-ACQUIRED PNEUMONIA
Community-acquired pneunonia (CAP) is a lung infection caused by Streptococcus pneumoniae, Mycoplasma pneumoniae, and Haemophilus influenzae, respiratory viruses, oral anaerobes, and OR fungi, resulting in symptoms in patients who have not been hospitalized or stayed in long-term care facilities.
MEDICAL-CARE-ASSOCIATED PNEUMONIA
(Health-care associated pneumonia)
Medical-care-associated pneumonia (MCAP) is a severe condition causing significant morbidity and increased mortality rates, primarily caused by a variety of bacteria including pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Acinetobacter, Haemophilus influenzae, Staphylococcus aureus, Streptocococcus pneumoniae, and oral anaerobes.
ASPIRATION PNEUMONIA
Aspiration pneumonia, a condition resulting from abnormal entry of material from the mouth or stomach into the trachea and lungs, can occur in community settings or healthcare facilities, and can be increased by decreased consciousness, swallowing difficulties, and nasogastric intubation.
OPPORTUNISTIC PNEUMONIA
Opportunistic pneumonia, caused by a person’s depressed immune system, can occur due to HIV, radiation therapy, chemotherapy, or long-term corticosteroid therapy, and may include viruses and bacteria.
PATHOPHYSIOLOGICAL CONCEPTS- pneumonia
○ Upper airway (nasopharynx and oropharynx)
○ Compromised systemic defence mechanisms (humoral and complement-mediated immunity
○ Impaired mucociliary clearance
○ Impaired cough reflex
○ Alveolar macrophages
○ Accumulation of secretions
Clinical Manifestations
Tachypnoea (^respiratory rate)
Impaired gas exchange resulting from damage to the bronchial mucus membrane and alveolar-capillary membrane.
Invasion of the lungs by micro-organisms cause an inflammatory response, fever and chills. The body’s immune response is increased requiring increased metabolic rate and increased oxygen demands.
Clinical Manifestations- Dyspnoea/^work of breathing (WOB)
An accumulation of thickened fluid in the alveoli and terminal bronchioles makes it harder for air to move into the terminal airways. The person needs to work harder to get air past these obstructions.
Clinical Manifestations- Productive cough
Whilst the cough may not always be productive, this results from the accumulation of thickened fluid in the alveoli and terminal bronchioles.
The resultant sputum may be green, yellow or rust-coloured (bloody).
Clinical Manifestations- Use of accessory muscles
This is a direct result of the increased WOB.