Respiratory system Flashcards
Respiration
- Air is inhaled through the nasal passage passing over the conchae where it is WARMED & MOISTENED.
- Foreign material is FILTERED by mucous secretions & hairs before entering lung tissue.
- Cilia sweeps mucous & debris up and out of the respiratory tract.
- Airflow continues through the nasopharynx & larynx into the trachea.
What does the upper respiratory tract consist of?
It is made up of the passageway that conducts air from the atmosphere to the lungs.
Nasal cavity (nose)
Mouth
Pharynx (throat)
Larynx (voice box)
What is the function of the upper respiratory tract?
Ensuring that the air entering the LRT is warm, moistened and filtered.
What structures does the LRT include?
- Trachea
- Right and left primary bronchi
- The constituents of both lungs- bronchi, bronchioles, alveoli, bronchial tree
What is respiratory failure?
It occurs when the lungs are not extracting enough oxygen from the atmosphere.
What is respiratory failure type I?
When the patient has low oxygen in their arterial blood- hypoxemic.
Pts would usually present with central cyanosis.
What is respiratory failure type II?
-When the patient is hypoxemic and hypercapnic.
* This is because a reduction in ventilation will result in an accumulation of co2.
- This is respiratory acidosis
What’s an example of a lower respiratory tract infection?
Tuberculosis.
- It’s caused by a slow airborne growing bacillus.
- Signs & symptoms include:
.Haemoptysis
.Weight loss
.Fatigue
.Pyrexia
.Night sweats
What is pneumonia?
- It is an infection of the small airways and alveoli.
- Inflammation & oedema causes the alveoli to become filled with fluid & exudate. (leak fluid out).
- It is mainly caused by inhaled pathogens.
- It can be hospital or community-acquired.
- Streptococcus pneumoniae is the most common pathogen.
A. What is the pathology of lobar pneumonia a classical example of?
B. What are the 4 stages?
A. Acute inflammation
B.
- Congestion- lasts up to 24 hours and is where there is an outpouring of protein-rich exudate into the alveolar space & inflammation of the alveolar wall.
- Red hepitisation- Lasts for a few days and is where there is a massive accumulation in the alveolar space of neutrophils, lymphocytes & macrophages.
- Grey hepitisation- This stage lasts for a few days and represents further accumulation of fibrin with destruction of WBC & RBC.
- Resolution- Occurs at about 8-10 days and represents the reabsorption of exudate and inflammatory debris.
What is croup & what age groups are affected?
Croup is a common viral respiratory illness in paediatrics.
- It occurs when there is viral invasion of the laryngeal mucosa leading to:
. Inflammation, oedema & hyperaemia (excess blood in the vessels)
. Narrowing of the subglottic region & to compensate, paeds breath more rapidly and deeply.
- Children aged 6 mths- 3 yrs are commonly affected and less likely after 6 years.
What is bronchitis?
What is Epiglotitis?
What is COPD?
A common lung disease causing restricted airflow and breathing difficulties.
What are 2 conditions that contribute to COPD?
- Chronic bronchitis- This is the continued, repeated injury to the bronchial tree resulting in an increase in inflammatory cells, increase in mucus production, and death of epithelial. This results in the bronchi getting clogged with mucus and inflamed.
- Emphysema- This is the permanent enlargement of airspace beyond the terminal bronchioles and destruction of alveolar walls. This results in:
. Destruction of lung tissue which results in a decrease in recoil activity.
. Enlargement of alveoli resulting in hyperinflation.
.Decrease in recoil activity which results in air trapping in the lungs.
