Respiratory 3 Flashcards
What is Eupnea
Ventilation
What happens during inspiration
Thoracic volume increases
Pump handle motion
Scalenes and upper external intercostals
Bucket handle motion
Lower external intercostals
What muscles are involved in quiet expiration
No muscles (passive)
What happens during expiration
Diaphragm relaxes, thoracic volume decreases
Lungs recoil, alveolar volume decreases, compresses gas molecules, pressure in alveoli increase
Air moves out into lower pressure atm
What is size of pressure gradients created by changes in alveolar volume in quiet breathing
Small
What happens as soon as muscles stop contracting
Pressure rises
Before inspiration what is the relationship between Patm and Palv
Equal
No pressure gradient, no air flowing
When is their no air movement
Quick between inspiration and expiration
As soon as muscles begin to contract what happens to pressure
It drops
What additional accessory or secondary muscles become activated during forced inspiration
- sternocleidomastoids
- neck and back muscles
- upper respiratory tract muscles
What do the sternocleidomastoids do during forced inspiration
Lift the sternum outward, contribute to water pump handle effect
What do neck and back muscles do during forced inspiration
Elevate pectoral girdle increasing thoracic volume and extend back
What do upper respiratory tract muscles do during forced inspiration
Decrease airway resistance by dilating pharynx and larynx
Muscles of forced expiration
Abdominal muscles
Internal intercostals
Triangularis sterni
Neck and back muscles
What do abdominal muscles do during forced expiration
Pushes some visceral organs upward and pushes diaphragm up
What do internal intercostals do for forced expiration
Create opposite bucket handle
What does triangularis sterni do for forced expiration
Pulls sternum inward, negative pump handle