Gas exchange

Gas Exchange

The process by which oxygen is transported to the cells and carbon dioxide is transported from the cells.

Ventilation

The process of breathing oxygen into the lungs.

Transport (gas exchange context)

The availability and ability of hemoglobin to carry oxygen.

Perfusion (gas exchange context)

Relates to the gas exchange in the cells.

Ischemia

Insufficient flow of oxygenated blood to tissues, may result in cell injury or death.

Anoxia

Total lack of oxygen in body tissues.

Hypoxia

Insufficient oxygen reaching cells.

Hypoxemia

Reduced oxygenation in arterial blood.

Upper Respiratory Tract

Includes the nose, nasal cavity, mouth, pharynx (throat), and larynx (voice box).

Lower Respiratory Tract

Includes the trachea, bronchi, bronchioles, alveolar ducts, and alveoli.

Compliance

Measure of the ease of lung expansion.

Diffusion

Oxygen and CO2 moving back and forth across the alveolar-capillary membrane.

Oxygen Saturation (SaO2)

Measures the amount of oxygen bound to hemoglobin.

SpO2

Oxygen saturation level as measured on a pulse oximeter.

PaO2

Pressure of oxygen dissolved in the arterial blood.

Impaired Gas Exchange Risk Factors

Includes age, smoking, presence of chronic medical conditions, immunosuppression, and prolonged immobility.

Chronic Hypoxemia

Indicated by finger clubbing.

Bronchoconstriction

Indicated by wheezes.

Pleural Friction Rub

Indicates pleurisy.

Oxygen Therapy

Intervention for decreased gas exchange involving positioning and respiratory support.

FiO2

The fraction of inspired O2 being delivered to the client.

Simple Face Mask

Delivers oxygen at 6-12L with 40-50% FiO2.

Non-Rebreather Mask

Delivers high flow O2 (10-15L) with up to 90% FiO2.

Bag Valve Mask

Can hook up to oxygen and deliver 100% FiO2 at 15L.