CCCSD - Respiratory Review

Normal Breathing

100

The diaphragm contracts. Increasing lung volume, and making the pleural pressure more negative. Air to rushes in and fills the lung.

Inspiration

200

The diaphragm relaxing, and intrinsic recoil of the lungs allowing air to be expelled passively

Expiration

300

During quiet breathing the amount of air that is inspired and expired 

Tidal Volume - Vt

400

The lungs ability to stretch and expand 

Lung compliance 

500

Volume in the alveoli after passive expiration 

Functional Residual Capacity 

Important to keep small airways open, thus prevention areas of collapse and allows for continual gas exchange. 

Respiratory Assessment

100

Intercostal, subcostal, suprasternal and supraclavicular use are examples of

Use of accessory muscles

200

Observing respiratory rate, pattern, effort, colour, accessory muscles, chest symmetry and tracheal position are examples of what component of the respiratory assessment?

Inspection

300

Discontinuous, popping sounds auscultated during breathing. Can be categorized as fine or coarse. 

Crackles 

400

Continuous, high-pitched, musical sounds. Often indicating narrowing of the airways

Wheeze 

500

Can be caused by trauma or a procedure that causes a leak from the respiratory tract, esophagus, or gastrointestinal tract. This can cause abnormal presence of air in the tissues beneath the skin.

Subcutaneous Emphysema 

Anatomy & Pathophysiology

100

I move particles at a rate of 3mm per min to the larynx where these particles are either coughed up or swallowed.  

Cilia 

200

I form 70-80 sq meters of surface area in close contact with capillaries for gas exchange. 

Alveoli 

300

When in network for gas exchange, each red blood cell passes by me single file for approximately 3/4 second, and exchanges 0₂ or C0₂ within 0.25seconds

 

Capillary Membrane

400

It takes 0.25 seconds for these levels to reach normal saturation when exposed to alveolar gas

Haemoglobin

500

A gas that diffuses 20 times more rapidly than oxygen 

C0₂

Respiratory Conditions

100

A build up of fluid in the interstitial space of the lungs 

APO

200

Viral replication, cellular damage, inflammatory mediators release, and recruitment of immune cells. Leads to airway obstruction, reduced mucociliary clearance and in severe cases cause pneumonia.

Respiratory Virus

300

Pathogen invades the alveoli, leading to an inflammatory response, accumulation of fluid, pus, and inflammatory cells within the alveoli. This contributes to impaired gas exchange.

Pneumonia

400

Loss of elasticity, the walls between alveoli are destroyed, alveoli become large and floppy because there is less surface area for gas exchange, airways are thick, inflammed and there is increased mucus production

Chronic Obstructive Pulmonary Disease - COPD 

500

Airway inflammation and hyper-responsiveness cause airway smooth muscles to contract and relax. 

Airway remodeling and mucous hypersecretion occur. 

These contribute to variable airflow obstruction. 

Additionally, chronic inflammation can lead to irreversible airway remodeling. 

Asthma

1. Airway inflammation

_{-Immune cell infiltration, cytokine release, IgE production}

2. Airway hyper-responsiveness

_{-Causes bronchospasm} 

3. Airway remodeling

_{-Repeated inflammation and repair can lead to long-lasting structural airway changes eg. thickening airway wall, increased smooth muscle mass, increased collagen under the epithelium}

4. Mucous hypersecretion

_{-Increased mucous production and inflammation and swelling of the airways, can lead to mucous plug formation further obstructing the airways}

Respiratory Failure

100

Characterised by Low Pa0₂ (Pa02 <50mmHg) but C0₂ is not elevated (paC0₂ <60 mmHg).

Type 1 Respiratory Failure or Hypoxemic Respiratory Failure 

200

Characterised by low Pa0₂ (<50mmHg) and elevated PaCO₂ (>60mmH) 

Type 2 Respiratory Failure 

300

Imbalance between the amount of air reaching the alveoli and the amount of blood perfusion the pulmonary capillaries. 

Ventilation-Perfusion (V/Q) Mismatch

400

Alveoli are well-ventilated, however there is poor gas exchange due to poor blood supply

Dead Space

_{More air than blood flow in lung segment}

Examples:

-PE

-Pulmonary Hypertension

500

Blood flowing past poorly ventilated alveoli that does not exchange gas. 

Poorly oxygenated blood then lowers the total oxygen content of the arterial blood - leading to hypoxaemia. 

Shunt/shunting 

Common causes of shunt include: 

- Pnueomnia and pulmonary oedema

- Tissue trauma - alveolar wall swelling

- Atelectisis collapse of alveoli from failure to expand 

- Mucus plugging