WEEK 3 - SPUTUM

Question 1

Asthma

Answer 1

RESTRICTIVE RESP CONDITION
## DESCRIPTION

Causes chronic inflammation in the airways, narrowing them and making breathing difficult. Asthma exacerbations are caused by irritation from the environment in the lungs.

Th2 cells are an immune cell subtype, and are excessively stimulated by environmental irritants causing asthma. Irritants such as smoke are received by dendritic cells and processed by Th2 cells, releasing cytokines such as Interleukin-4 and IL-5. These cytokines promote an inflammatory response.

This hypersensitive inflammatory response leads to spasming contractions of the smooth muscles in the bronchioles and increased mucus secretion, narrowing the airways. These changes are reversible.

Overtime, some irreversible changes can occur. Edema, scarring and fibrosis can occur in the bronchioles, resulting in thickening basement membranes, permanently narrowing the airways.

TYPES OF ASTHMA

• Intermittent asthma —>
• mild persistent asthma —>
• moderate persistent asthma —>
• severe persistent asthma

CAUSES/RISK FACTORS

• genetic - family history leads to increased risk of having asthma (childhood asthma)
• environmental factors - hygiene hypothesis (later onset of asthma)

SYMPTOMS

• coughing
• chest pain/tightness
• wheezing
• dyspnea (difficulty breathing)

TREATMENT

• avoid contact with triggering substances
• medication - bronchodilators, corticosteroids

Question 2

Acute Bronchitis

Answer 2

RESTRICTIVE
DESCRIPTION

Inflammation of the bronchial tubes. Causes a cough that often brings up mucus, as well as shortness of breath, wheezing and chest tightness.

Often brought on by exposure to causing viruses (most common) and bacteria, and can be irritated by known irritants (smoke, dust, mold, vapours)

SYMPTOMS

• coughing up mucus
• wheezing
• shortness of breath
• chest tightness

CAUSES/RISK FACTORS

• caused by viral infection, like flu or the cold
• smoking
• exposure to polluted areas
• prior history of asthma

TREATMENT

• use of antibiotics
• increase fluid intake, orally or IV
• humidifiers

Question 3

Chronic Bronchitis

Answer 3

OBSTRUCTIVE
Inflammation of the bronchial tubes. Is classified as chronic when there is a productive cough for 3 or more months of the years for 2+ years.

Chronic Bronchitis and Emphysema fall underneath Chronic Obstructive Pulmonary Disease (COPD). CB and Emphysema commonly co-exist, as they are often brought on by their major risk factor, smoking. CB is defined by clinical features like a productive cough, well as Emphysema is defined by structural changes like change in air spaces in the lungs.

CAUSES/RISK FACTORS

• Smoking
• air pollutants
• dust and cilia
• genetic factors (family history)

SYMPTOMS

• Wheezing
• Crackles
• Hypoxemia - low O2 in blood
• Hypercapina - high CO2 in blood
• Cyanosis - blue discolouration of the skin
• Pulmonary hypertension - large amount of pulmonary vasoconstriction due to innefective gaseous exchange leads to increased pulmonary resistance, increasing BP.
• Lung infection

RELEVANT DIAGNOSIS

• FEV1/FVC ratio is a metric that can recognise COPD. A normal ratio is 80%, but can drop to around 50% in COPD patients.
• REID INDEX - Thickness of Glands / Thickness of Wall

TREATMENT

• reducing risk factors
• managing associated illnesses
  
  • supplemental O2
  • medication
    
    • bronchodilators
    • inhaled steroids
    • antibiotics

Question 4

Bronchiectasis

Answer 4

DESCRIPTION
Obstructive
Bronchial-dilation

Characterised by airways that have been abnormally enlarged. More susceptible to successive infections, as it allows an increase in bacterial colonisation in the bronchi/oles. The ongoing inflammation of the airways overtime leads to airway remodelling.

The symptoms of BE disrupt vital processes that occur in the respiratory system. Including

• mucociliary elevator
• cough reflex
• antibody production (IgA)
• antimicrobial peptides

Airway Neutrophilia is the hallmark of BE. Excessive presence of neutrophils are present in BE as the injured epithelial in the walls of the airways release cytokines (IL1, IL8) that attract neutrophils to the airways.

CAUSES/RISK FACTORS

These factors trigger the initial insult, which initially dilates the airways.

• Bacterial Infection
• A1 Antitrypsin Deficiency
• Asthma
• Bronchial Obstruction (aspiration, tumour obstruction, lymph node swelling)
• Cystic Fibrosis
• COPD

SYMPTOMS

• excessive sputum production - Purulent (off white, yellowy sputum) in 2/3 of patients
• Haemoptysis (coughing up blood) - 60% of patients
• Infections
• Tenacious cough - Chronic
• Weight Loss
• Respiratory comprimise
• Dyspnoea (SOB)
• Wheezing
• Yellow Nail syndrome

RELEVANT DIAGNOSIS

• High-resolution CT - measures Bronchial diameter
  
  • Airway diameter > accompanying blood vessel = BE
• X-ray, visible enlarged airways cystic shadows
• Bronchoscopy
• Spirometry

TREATMENT

• Haemoptysis - embolisation or Lobectomy
• Exacerbations - Antibiotics, long term macrolides, steroids, bronchodilators
• Lifestyle - Smoking cessation, vaccines, exercise
• Postural Drainage x2 a day
• Chest physiotherapy
  
  • breathing techniques
• Inhaled bronchodilators

Question 5

Cystic Fibrosis

Answer 5

DESCRIPTION

An inherited disorder characterised by a defective CFTR gene that results in impairment in the ability to produce normal body secretions (sweat, mucus).

Life shortening

Thick, stickier mucus is produced, which is more difficult to remove from the lungs. This causes dysfunctional cilia, creating a breeding ground in the respiratory tracts for recurring respiratory infections. This leads to Bronchiectasis.

CAUSE/RISK FACTORS

• Genetically inherited disorder

SYMPTOMS

• secretions thicker and cause obstruction
• Increased salt in sweat - dehydration risk (salt crystal formation on skin) - CFTR assists in moving Chloride, an element of salt, through cells. Stuck in sweat ducts.
• stickier mucus
• Infertility in males - 98% of male CF patients are infertile due to poor development of Vas Deferens. 15-30% infertile females.
• coughing, wheezing
• SOB
• Poor growth
• Vomiting

RELEVANT DIAGNOSIS

• Newborn screening - Heel prick
• Sweat testing
• Genetic testing (CFTR gene)

TREATMENT

• vaccines
• airway clearance measures (chest physio)
• aerobic exercise
• CFTR modulators
• antibiotics
• bronchodilators
• NSAIDS (ibrupofren)
• nutritional supports (vitamins, 50% calorie surplus)

Question 6

Sputum matching (purulent, serous, rusty, mucoid, bloody)

Answer 6

purulent - green/yellow - broncho-pulmonary infection

serous - watery thin, pink and frothy - pulmonary oedema

rusty - brick/rusty red or golden yellow - pneumococcal pneumonia

mucoid - thick, white/grey - inflammatory exudate from chronic bronchitis, emphysema, asthma

bloody - bright red - lung tumour, tuberculosis

Question 7

define shunting

Answer 7

Shunting: the right ventricle is forced to work harder to pump blood through vasoconstricted blood vessels. This excess stress leads to hypertrophy of the right ventricle and increases the risk of heart failure.

Question 8

Ventilation vs perfusion

Answer 8

Ventilation (V) refers to the flow of air into and out of the alveoli, while perfusion (Q) refers to the flow of blood to alveolar capillaries