Pulmonary Physiology

These flashcards cover key concepts in pulmonary physiology, including major functions, gas exchange processes, laws governing respiratory mechanics, lung volumes, and impact of diseases.

What is the primary function of the respiratory system?

To maintain systemic arterial blood gas levels within normal range.

What are the main components of the respiratory system?

Lungs, chest wall, and pulmonary blood vessels.

What process allows for gas exchange in the lungs?

Ventilation, where air enters the lungs and comes into contact with alveoli.

What is Boyle's Law related to in respiratory physiology?

It explains the gas flow during ventilation, as mechanical events change lung volume, resulting in pressure gradients.

What is the significance of Dalton's Law in pulmonary physiology?

Each gas in a mixture exerts a partial pressure proportional to its concentration, and the sum of partial pressures equals the total pressure.

How does Henry's Law apply to gas exchange?

The volume of dissolved gas is proportional to its partial pressure.

What does spirometry measure?

Lung volumes and gas flow rates during pulmonary function testing.

What is tidal volume (Vt)?

The amount of air breathed in and out during normal breathing.

What is vital capacity (VC)?

The maximum possible volume that can be expired following a maximal breath inspired.

What happens during an obstructive lung disease?

There is an obstruction to airflow, characterized by high airway resistance.

What role do surfactants play in the lungs?

They maintain alveoli open during expiration, allowing more time for gas diffusion and counteracting surface tension.

What effect does pneumothorax have on lung function?

It causes the lung to collapse as intrapleural pressure equals atmospheric pressure.

What is airway resistance influenced by?

Airway radius, lung volume, and turbulent gas flow.

What is the clinical significance of FEV1.0?

It measures the volume expired in the first second of a forced expiration test, indicating airway obstruction.

What distinguishes obstructive from restrictive lung diseases in spirometry results?

In obstructive diseases, FEV1/FVC ratio is decreased; in restrictive diseases, the ratio is normal or increased.

What is the typical partial pressure of oxygen in inspired air at sea level?

Approximately 160 mm Hg.

What impact does increased lung compliance have?

It causes airway obstruction during expiration, as seen in pulmonary emphysema.

What are the primary muscles involved in inspiration?

Diaphragm and external intercostal muscles.