Flashcards in Pulnomary response to exercise Deck (21):
What is the V/Q ratio
The balance between ventilation (bringing in oxygen and removing carbon dioxide) and perfusion (removing oxygen from the alveoli and bringing in carbon dioxide)
What is would an average Vo2 max value be for chris froome a heart failure patient and a normal individual
Chris froome = 84 (ml/kg/min)
Normal= 40 (ml/kg/min)
Heart failure 10 (mlkg/min)
What is external respiration?
02 uptake (VO2) to provide oxygen to transport around the blood and carbon dioxide output (VCO2) to clear CO2 produced metabolically and CO2 produced from the buffering of acids to maintain arterial PH
What is internal respiration?
-02 consumption in the mitochondria for ATP production by oxidative phosphorylation
-Carbon dioxide production by break down of carbon chains in the TCA cycle
What are the primary symbols?
P= Pressure/ Partial Pressure
Q= Blood volume
F= Fractional concentration
V= Volume of gas
upside down triangle= mixed venous
What are the secondary symbols
What are the symbols for fractional concentration of expired CO2, Tidal volume, Partial pressure of 02 in arterial blood and volume of CO2 expired?
- Fractional conc of CO2= FeCO2
- Tidal volume= VT
- Partial pressure of 02= PaO2
- Volume of CO2 expired per unit of time = VCO2
What is the conducting zone and respiratory zone? How big is the conducting zone on average?
- Conducting zone: Transport of gas between atmosphere and alveoli (anatomical dead space = 150ml)
- Respiratory zone= Alveolated region where gas exchange occurs - including the transitional zone
What is total ventilation?
Total amount of air that flow out of respiratory system in one minute
(Total ventilation= Tidal volume x Respiratory rate)
What is alveolar ventilation?
(Total ventilation - Physiological deadspace) OR Total ventilation - (Physiological deadspace x respiratory rate)
What are the functions of the lung?
- Alveolarise the blood moving 02 into pulmonary capillary and move CO2 into alveoli
- Regulate acid based balance
- Water/Heat loss
-Filter unwanted material
- Blood reservoir
What is ventilation?
- Mechanical process of moving gas in and out of the lung
What happens to the cross sectional area when switching from the conducting to respiratory zone and what is the risk of this?
- Huge increase in cross sectional area increasing the risk of infection
What happens during Tachypnoea?
- Increases in alveolar ventilation are far lower as VA = (VT- FR) - (VD- FR)
- Total ventilation stay the same as breathing frequency increases but so does VD- FR
What is alveolar ventilation?
- Fresh inspired air available for gas exchange
Show the relationship between VCO2, VA, FACO2 and PCO2
VCO2 = VA x FACo2
VA = VCO2/ FACo2
VC02/PCo2 x k
What happens during hyperventilation and hypoventilation?
- Hyperventilation: Breathing more than required to clear metabolically produced CO2, PaCO2 falls
- Hypoventilation: Breathing less than required to clear metabolically produced CO2 - PaCO2 rises
What is the term for the increase in ventilation in response to exercise?
What happens to PaCO2 during moderate exercise? And what does this suggest
PaCO2 is normally well maintained suggesting VA very closely matches VCO2
What is total ventilation? Including VCO2 and PACO2?
863 x VCO2/ PACO2 (1-VD/VT)