BREATHING Flashcards
What muscles are used during respiration?
intercostal muscles
- external and internal
What are possible accessory muscles are used during respiration?
Sternocleidomastoid
Scalenes
Abdominals
Pectoralis minor
What happens to pressure during inspiration?
atmospheric pressure is HIGHER than the intrathoracic pressure
ACTIVE pressure
What happens to pressure during expiration?
atmospheric pressure is LOWER than the intrathoracic pressure
PASSIVE pressure
What controls your breathing?
Respiratory centre in the brain stem
Group of neurons in the pons and medualla
What does the medullary respiratory center control?
The rhythmic nature of breathing
(inspiratory and expiratory centres, 2 interconnect control centers)
What nerve innervates the diaphragm?
Phrenic nerve
What happens to muscles during inspiration?
they CONTRACT
What happens when the expiratory centre is initiated?
the expiratory muscles are needed during forced expiration
What are the 2 types of neurons in the PONS respiratory centre?
stimulating neurons
inhibitory
What does the pons respiratory centre do?
Coordinates actions of the medullary center to produce a smooth breathing process
What does the pons respiratory centre either increase or decrease?
DEPTH and LENGTH of inspiration!
What are the factors influencing the respiratory centre?
direct stimulation
stimulation through sensors
What are factors that influence breathing?
- chemoreceptors
- blood pressure
- cerberal cortex
- inflation/deflation reflex
- hering-breuer reflex
- higher brain centers
- body temp
What are the chemists of the brain?
Chemoreceptors
What are the 3 things that the medulla recognizes and changes?
- PO2 (oxygen)
- PCO2 (carbon dioxide)
- PH (hydrogen ions)
Increased PCO2 results in…..
FASTER breathing and greater volumes of air
Decreased PCO2 results in….
INHIBITION of the medulla rhythmicity and SLOWS the respirations
A RISE in BP….. does what to RR?
slows resp rate
A DROP in BP… does what to RR?
increases the rate and depth resps
What does your cerebral cortex do?
increases or decreases respirations voluntarily
What is the inflation/deflation reflex?
stretch receptors in the visceral pleura that are sensitive to the degree of stretching of the lungs
during inspiration impulses are sent directly to the resp centre via the VAGUS nerve, inhibits impulses and promotes expiration and deep inspiration
What is the hering-breuer reflex?
when the air has been INSPIRED, lungs expand enough to stimulate stretch receptors
stretch receptors send inhibitory impulses to the inspiratory center
relaxation of the inspiratory muscles occurs and expiration begins
What are examples of higher brain centers?
periods of anxiety, fear, pain, excitement or temp via hypothalamus
voluntary alteration of resp patterns (provided by cerebral cortex and can be overriden by the chemorecptors)
