Flashcards in 3.6.3. Respiratory System Regulation Deck (27)
Hyperpnea? I believe this is usually called tachypnea...
Hyperpnea - increased breathing that matches metabolic needs (i.e. during exercise)
Brachypnea - shortness of breath (dyspnea)
Hypoxia vs. Hypoxemia
Hypoxia vs. Hypoxemia - low tissue oxygenation vs. low blood oxygen (low paO2)
What and where is the CPG?
“central pattern generator” creates breathing cycle, with input from central chemoreceptors and sensory integrators; the specific site of the CPG is unknown
What are the 3 parameters that influence breathing?
Arterial levels of blood gases
position and stress on structural components
measured at the CNS and in peripheral positions via
central/peripheral chemoreceptors and mechanical (stretch) receptors
In 1812, the _____ was identified as essential for breathing
In 1812, the medulla was identified as essential for breathing
In 1923, the _____ was identified as necessary for breathing
In 1923, the pons was identified as necessary for breathing
2 parts to the Pons
Discuss the apneustic center of the pons
located in the lower pons
stimulates inspiration, producing a deep and prolonged inspiratory gasp (apneusis)
Discuss the pneumotaxic center of the Pons
located in the upper pons
inhibits inspiration, regulates respiratory volume and rate
2 parts of the medulla
Dorsal respiratory group (containing the nucleus of the solitary tract)
Ventral Respiratory group:
Discuss the signaling involved in the dorsal respiratory group of the medulla and the end result
recieves input from the thorax and abdomen regarding pO2 and pCO2 [via the vagus and glossopharyngeal n.]
communicate with pre motor neurons [via the phrenic n.]
Is primarily responsible for inspiration, generates the basic rhythm for breatihing
What is the ventral respiratory group responsible for and when is it active?
primarily responsible for expiration
not active during normal, quiet breathing; expiration is passive
is activated during exercise OR when expiration becomes and active process
What part of our breathing do we control and how?
voluntary control of breathing (i.e. breath holding)
In regards to CO2 or H+ responses by receptors, what types recognize these changes and which one is most important?
The response of peripheral chemoreceptors to CO2 is less important that the response of the central chemoreceptors for CO2 (or H+)
What does our body due in response to Hypercapnia, or increased paCO2?
activates the central medullary chemoreceptors and increases breathing rate (not as important as pH)
activates peripheral carotid and aortic bodies to increase breathing rate (more important than pH, but less than O2)
What is acidosis?
What is our body's response to acidosis?
activates the central medullary chemoreceptors and increases breathing rate
activates peripheral carotid and aortic bodies to increase breathing rate (least important stimulus)
What happens during hypoxia?
Only activates the peripheral carotid and aortic bodies; most important stimulus in peripheral system (if <60mmHg)
Discuss central control of breathing
sensitive to the pH of the CSF
decreased pH increases the breathing rate
CO2 diffuses from arterial blood across the BBB and causes the drop in pH (via carbonic anhydrase which yields H+ and HCO3-) which is measured directly by the medullary chemoreceptors
Where are the carotid bodies and what system of breathing control are they a part of?
Peripheral control and they are located at the bifurcation of the common carotid arteries
Where are the aortic bodies?
aortic bodies are located above and below the aortic arch
How do arotic bodies respond?
decreases in arterial O2 will stimulate the peripheral chemoreceptors to increase the breathing rate
this only occurs when pO2 is <60mmHg
increases in pCO2
stimulate chemoreceptors and increase breathing rate
Where are lung stretch receptors and what do they do?
located in the smooth muscle of the airways
are stimulated by lung distension
decrease breathing frequency (Hering-Breuer reflex)
Where are irritant receptors and what do they do?
located between airway epithelial cells
stimulated by foreign substances
Where are juxtacapillary receptors and what do they do?
located in the alveolar walls, close to cappilaries
engorgement of the capillaries (as seen in left heart failure) stimulates and causes rapid shallow breathing