Transport of O2 and CO2 and the Regulation of Ventilation Flashcards
What are the factors that shift the O2-Hb dissociation curve to the right?
- Increased CO2 (Bohr effect)
- Increased Hydrogen ion (decrease pH)
- Increased T
- Increased 2,3 bisphosphoglycerate (2,3 BPG)
Which shift, left or right, does it become easier to extract O2 from tissue?
rt shift
How does chronic anemia shift the O2-Hb curve?
CHRONIC anemia shifts to right
What is molecular equation for conversion of bicarbonate with CA?
Bicarbonate is formed in the RBC but carried where?
in plasma
Hyperventilation not only lower PCO2 but also lowers what?
the CO2 content
What are the 2 groups of chemorectors that regulate alveolar ventilation?
central and peripheral
What is the main stimulating factor for central chemoreceptors?
stimulated by cerebrospinal fluid [H+} and CO2 may be due to H+ formed from CO 2 because H+ can’t easily cross itself
Where are the peripheral chemoreceptors for alveolar ventilation found?
carotid bodies
aortic bodies
What are the 2 different receptors that the aortic and carotid bodies have?
H+/CO2 receptors
PO2 (not O2 content)
What stimulate PO2 receptors?
strongly stimulated only by dramatic decrease in systemic arterial PO2
Where are the central respiratory centers found?
- medullary centers
-inspiratory center
-expiratory center
A lesion found where on the spinal cord could prevent diaphragmatic breathing?
C1 or C2 but not a complete C6 or lower lesion
What is apneustic breathing? What is it caused by?
a prolonged inspirations alternating with a short period of expiration
Caused by loss of the normal balance between vagal input and the pons-medullary interactions
What is Cheyne-Stokes breathing? What can it be caused by?
a periodic type of breathing that has cycles of gradually increasing depth and frequency followed by a gradual decrease in depth and frequency between periods of apnea
midbrain lesions or CHF
