Hypoxemia algorithm Flashcards
1
Q
How would you calculate the Aa gradient
What is the normal Aa gradient
-how would you adjust for age
A
PAO2 - PaO2
PAO2 = (FiO2 x (Pb- PH2O)) - (PaCO2/R)
1.33-2kPa but increases with age
(age/4) +4
2
Q
How would you interpret a normal Aa gradient
A
(age/4) + 4
-hypoxemia due to hypoventilation or altitude
3
Q
How would you interpret an increased Aa gradient
What would you do
A
Problem with the alveolar capillary exchange surface
FiO2 100%
- responsive => due to low V/Q
- decreased response => due to a shunt