Lecture 5 Regulation of Respiration Flashcards
what controls RR to meet the need for o2 to the body?
Medulla
What is the dorsal respiratory group mainly responsible for?
Inspiration and sensory information
what peripheral receptors does the dorsal respiratory group sense specifically?
Chemoreceptors
Baroreceptors
Lung Receptors (distention and filling)
the dorsal group fires of two sequential actions in respiratoin?
- inspiration
2. inhibition of inspiration
although the dorsal group regulates respiration in “ramping” up slowly, and expiring quickly all under 2 seconds, what else assists in that process?
The pneumotaxic center
What does the pneumotaxic center mainly control
rate and pattern of breathing
where is the pneumotaxic center located?
Dorsal pons
what is the MAIN goal of the pneumotaxic center?
To shorten inspiration, and thereby increasing the frequency
What is the name of the effect when the Pneumotaxic center senses lung stretch at 1.5 liters, abruptly ending inspiration?
Hering Breuer effect (prevents damage from overfilling)
What 3 substances in order of importance regulate breathing?
- Co2 (Hypercapnia is the biggie)
- H+ (less mobile than co2)
- Oxygen (very little contribution here)
Physiologically, will you generally see an accumulation of co2 before acidity increases, or acidity before co2 increases?
Co2 will accumulate first, which leads to production of acid (H+)
Although co2 is the main contributor of breathing, what is the STRONGEST contributor if it accumulates enough?
Hydrogen ions (H+) (Remember: renal system still does its job, but if H+ gets high to make an effect, its likely super high)
o2 as a regulator will not become functional until peripheral chemo receptors detect a drop below what value?
70mmhg po2
at what value will the low po2 causing a doubling of breathing?
60mmhg po2
in what environmental condition does o2 begin to play a more important role in breathing regulation?
low o2/high altitude situations
b/c you blew off all your co2 over compensating for low atmospheric o2
our bodies pco2 sensors can vary in sensetivity, and can still control breathing albeit with a much lower pco2 concentration in what 2 conditions?
Po2 falls (with less oxygen we dont need as much co2 to trigger increase in RR)
Ph falls (in a more acidic state, we dont need as much co2 to trigger the same respiratory response)
how do we compensate for chronically low oxygen environments?
RBC’s make more hemoglobin
what type of breathing is the dorsal group mainly responsible for?
quiet breathing (in front and to the side of the ventral group)
what breathing type then is the ventral group responsible for?
aerobic breathing (during exersize or running from russian tiger)
What does the ventral group have that makes it work so well?
The pneumotaxic center
What does your body do when anticipating exersize?
increases HR and RR (which temporarily drops pco2 levels)
does the movement of body joints somehow contribute to anticipation and help increase the RR?
yes
below what value is technically considered hypoxia in po2?
below 60mmhg
when a pearl diver holds his breath, even though his po2 is dropping, the urge to inhale is coming from where?
pco2 deprivation
what type of breathing occurs when the respiratory can no longer function within its parameters, and attempts to over-regulate respiration?
Cheyne-Stokes breathing
what three pathologies can lead to cheyne stokes breathing?
- increased time blood takes to get to brain (heart failure)
- brain damage
- severe acid/base disturbances
Do cheyne stokes respirations begin at peak of pulmonary co2 of lung blood, or peak of pco2 in respiratory neurons?
Cheyne stokes starts at PEAK of pco2 LUNG BLOOD
What receptors located on the alveolar epithelium and vascular endothelium detect any engorgement of pulmonary capillary blood that when excited make you feel SOB?
J-receptors
when is mannitol given?
when the brain swells and depresses the respiratory center
what everyday OTC drug stimulates the respiratory center
ASA (anesthesia depresses it)
