Respiratory conditions and drugs Flashcards
What is croup?
Inflammation of the larynx, trachea and bronchi
What is the cause of croup?
Usually a viral infection (most commonly parainfluenza ≈75% of all cases) invading the laryngeal mucosa leading to inflammation, hyperaemia and oedema
Can occasionally be bacterial (mycoplasma pneumoniae)
What are the main symptoms of croup?
Dyspnoea
Seal bark cough
Stridor
Fever
How can croup cause death?
Narrowing of subglottic airways cause dyspnoea (rapid and deep) hypoxia and hypercapnia progressing to respiratory failure and eventually cardiac arrest
What are the signs of peadiatric respiratory distress?
Intercostal recession
Tracheal tug
Paradoxical respiration (see-saw breathing)
Dyspnoea
Cyanosis
Hypotonia
What type of virus is parainfluenza?
RNA-circus, negative sense, helical, linear, non-segmented virus
What can non vaccinated children presenting with croup symptoms be more susceptible to?
Diphtheria infection
Approximately what percent of pre-school children contract croup?
6%
At what time of year do croup hospital admissions peak?
Late autumn, September to December
At what ages is croup most common?
6 months to 3 years, peak incidence is between 18 and 24 months. It is uncommon after the age of 6
Which scoring systems can help with estimating the severity of croup symptoms?
Westley croup score
Modified Taussig croup score
How is asthma defined?
It is a descriptive term and hard to define. Guthrie (2019) summarises it as “Chronic inflammation of the airway characterised by intermittent airway obstruction and hyperactivity”
What is the pathophysiological process of asthma?
Genetic factors give patients hyper-responsiveness then:
Environmental factors (smoking, pollution)
+
Triggers (allergens, irritants)
=
Clinical asthma (oedema, hyper-secretion of mucus)
+
Airway remodelling
What can trigger airway hyperresponsiveness?
Upper respiratory tract infections (URTs)
Chest infections
Allergens (Pollen, animal hair, dust, mold etc.)
Air pollution, cigarette smoke, chemicals
Drugs (Aspirin, NSAID’s, Beta-blockers)
Cold air
Exercise
What is COPD?
Umbrella term for Emphysema and chronic bronchitis
-Destruction on lung parenchyma and abnormal inflammatory response to noxious particles
How do pre-dispositions and environmental factors cause COPD?
Pre-dispositions in the genome negatively affect the lungs’ ability to prevent damage to its tissue. Environmental insults such as pollution and smoking cause free radicals to be produced in the lungs and an inactivation of lung anti-proteases.
Both of these leads to chronic inflammation and damage of airways and parenchyma
What is the Haldane effect?
An increase in pO2 causes Hb to lose its affinity for CO2
What are risk factors for spontaneous pneumothorax?
Smokers
Males
Tall and slender build
Respiratory diseases (Asthma, COPD, Lung Ca, ILD etc.)
Infection (rarely)
What different classes of pneumonia are there and how are they defined?
Many classes all defined by the wider source of infection. Hospital acquired, community acquired etc.
What are the four stages of pneumonia?
Early congestion
Red hepatization
Gray hepatization
Resolution
What causes pneumonia?
Infection, usually bacterial but can be viral
What is pneumonia?
A respiratory illness that causes the alveoli to fill with blood cells, pus, and other liquid.