Respiratory Physiology Flashcards
How many lobes are the lungs divided into?
5 lobes (3R, 2L)
What are each lobe is divided into what segments?
Bronchopulmonary segments
What are the body structures?
Chest wall, visceral pleura, parietal pleura, diaphragm
Visceral pleura
Covers the external lung surface including fissures
Parietal pleura
Covers the thoracic wall/superior face of the diaphragm. Forms the lateral walls of the mediastinal enclosure
What is the intrapleural pressure?
756mmHg (-4mmHg)
What is the Collapsing force of the lungs?
4mmHg
What is the Intrapulmonary pressure?
760mmHg (0mmHg)
Pulmonary perfusion
Requirements; adequate blood volume, intact capillaries, efficient pumping action by the heart. Hemoglobin, carbon dioxide
The physiological process is dependent on what three laws?
Boyles law, Dalton’s law, Henry’s law
What three processes make up respiration?
Ventilation, diffusion, perfusion
Ventilation
The mechanical process that moves air into and out of the lungs
What are the two phases of ventilation?
Inspiration, expiration
Boyle’s Law
When temperature is constant, the pressure of a gas varies inversely with it’s volume; increasing and decreasing pressure to cause air to either use in/out.
What are the two types of inspiration?
Active (normal), forced
Active inspiration
Stimulus from respiratory center of the brain (medulla), transmitted via phrenic nerve to diaphragm and to spinal cord/intercostal nerves stimulating intercostal muscles
Forced inspiration
During heavy respiratory demand, accessory muscles assist to further increase the intrathoracic area
What are the 4 accessory muscles that assist in forced inspiration?
Sternocleidomastoid, scalenes, pectoralis minor, abdominal wall
What are the two types of expiration?
Passive (normal), forced
Passive expiration
Stretch receptors in lungs signal respiratory center via vagus nerve to inhibit inspiration
Forced expiration
Required in some diseased states or during exercise; active process requiring energy, uses internal intercostals and abdominal muscles
Lung volumes in adult male
Total lung capacity (6000mL), vital capacity (4800mL), inspiratory reserve (3000mL), tidal volume (500mL), expiratory volume (1200mL), residual volume (1200mL)