Respiratory Flashcards
(43 cards)
Function of Respiratory Tract?
- Exchange carbon dioxide from blood with oxygen from lungs.
- Exchange takes place where pulmonary capillaries are in direct contact with the linings of the lung terminal air spaces(alveoli).
What makes up the respiratory tract?
- Upper respiratory tract (structures located outside the thorax; nasal cavity, pharynx & Larynx)
- Lower respiratory tract (located almost entirely within the thorax; trachea, bronchial tree, lungs)
- Oral cavity, Ribcage & Diaphragm
What is the Nasal Cavity?
- Internal portion of the nose
- Lies over roof of mouth
- Hollow structure separated by midline partition (septum). The septum has rich blood supply.
Cavity divided into: larger respiratory region, smaller olfactory region.
Cavity is connected to the pharynx through two openings(internal nares).
- Region is lined with cilia; filters out large dust particles.
- Inhaled air circulates cavity being warmed by close contact with blood from capillaries.
- Mucus secreted by goblet cells helps moisten the air.
What Is the Pharynx?
- Tubelike structure.
- Approx 12cm long.
- Serves as common pathway for respiratory and digestive tracts.
- Has 3 anatomical divisions: nasopharynx, oropharynx & laryngopharynx.
- Lined with ciliated mucous; helps remove large dust particles.
- Changes shape to allow vowel sounds to be formed during speech.
What is the Larynx?
Voice Box
- Triangular shaped
- Short passage connecting pharynx & trachea(lies in middle of neck)
- Protects airways against entrance of liquids/foods during swallowing: through glottis & epiglottis which act as trap doors to ensure liquids/food routed into oesophagus & not trachea.
- Lined with ciliated mucous; helps remove large dust particles.
What is the Trachea?
Windpipe
- 11cm tube
- Lies in front of oesophagus
- Extends from larynx to fifth thoracic vertebra (where divides into right & left bronchi.)
What’s is the Bronchi
- Trachea divides at fifth thoracic vertebra into left & right bronchi.
- Each bronchi divide & subdivide into bronchioles (resembling upside down tree, giving rise to bronchial tree term)
- Divisions continue till form terminal bronchioles
- From terminal bronchioles alveolar ducts & sacs exist; walls of which consist of alveoli where gaseous exchange takes place.
- Bronchial tree is lined with epithelial acting as a defence mechanism known as mucociliary escalator; cilia on surface beat upwards in organised waves of contraction to expel foreign bodies.
What do the Lungs consist of?
- Paired, cone-shaped organs within thoracic cavity.
- Divided into lobes; left has 2 lobes, right has 3.
Thoracic cavity - Role
- Important role in respiration; larger when chest raised/smaller when lowered affecting inspiration/expiration.
Pleural Membrane - What is it/Role
- Encloses the lungs; inner membrane covers lungs, outer membrane is attached to thoracic cavity.
- If Plura inflamed respiration becomes painful
Pleural Cavity - What is it/Role
Between Plural Membranes
- Contains fluid
- Prevents friction between membranes during breathing.
What is Coughing
- Body’s defence mechanism; attempts to clear airways of foreign bodies/particulate matter
- Most common respiratory symptom; manifestation of abnormalities of respiratory tract.
- Can be productive (chesty) or non-productive (dry/tight/tickly)
- Usually self limiting & will resolve in 3-4 weeks without antibiotics (British Thoracic Society Guideline 2019)
What is Mucociliary Escalator
- Defence mechanism of airways against foreign bodies/particulate matter.
- Consists of upward beating of finger-like cilia in bronchi moving mucus and entrapped forging bodies to be expectorated or swallowed.
Issues With A Cough
- Debilitating to patients well-being
- Disruptive to family, friends, work colleagues
Acute Cough
CKS Definition
- Cough present for less than 3 weeks
- Can take up to 4 weeks or more to fully resolve though.
Subacute cough
CKS Definition
- Cough present for 3-8 weeks
Chronic Cough
CKS Definition
- Cough present for more than 8 weeks
Referral Criteria For Cough
- Coughs other than acute (>3 week duration)
Acute Cough - Cause
- Usually caused by viral upper respiratory tract infection (URTI)
- School children experience > cough episodes yearly than adults.
Upper Respiratory Tract Infection (URTI) - Aetiology
90% caused by viruses:
- respiratory syncytial virus
- rhinovirus
- viral influenza
[Exhibits seasonability with higher viral URTI incidence seen in winter months]
10% caused by bacteria:
- Streptococcus pneumoniae
- Haemophilus influenza
- Staphylococcus aureus
- Klebsiella pneumoniae
these infections often have a viral element
- Reflex Process
Cough Production Process
Five Part Reflex
1. Receptors located mainly in the pharynx, larynx, trachea & large bronchi bifurcations are stimulated via mechanical, irritant or thermal mechanisms.
2. Neural impulses are then carried along afferent pathways of the vagal and superior laryngeal nerves, terminating at cough centre in medulla.
3. Efferent fibres of vagus and spinal nerves carry neural activity to muscles of the diaphragm, chest wall & abdomen.
4. These muscles contract
5. The glottis opens suddenly creating the cough.
Underlying Causes of Cough - Relative Incidence in Community Pharmacy
Most Likely: Viral Infection
Likely: Upper airway cough syndrome (formerly known as postnasal drip & includes allergies), acute bronchitis
Unlikely: Croup, Chronic bronchitis, Asthma, Pneumonia, ACE-Inhibitor induced
Very unlikely: Heart failure, Bronchiectasis, Tuberculosis, Cancer, Pneumothorax, Lung Abscess, Nocardiasis, GORD.
Questions to ask to gain information on a patient/ patients cough.
- Sputum Colour
- Nature of sputum
- Onset of cough
- Duration of cough
- Periodicity of cough
- Age of patient
- Smoking history
Sputum Colour
- Question to ask relating to patient cough & Relevance of answer.
Mucoid (clear/white) - Normally little consequence, suggests no infection is present.
Yellow/Green/Brown: Indicates infection; mucopurulent sputum is generally caused by a viral infection & dose not require automatic. referral.
Rust Coloured (Haemoptysis): Pneumonia
Pink Tinged: Left Ventricular failure
Dark Red: Carcinoma
Bright red blood: sputum with can occur as a single event due to the force of coughing causing blood vessel to rupture. This is not serious & required no automatic referral.