Flashcards in 12. Oxygen content of blood Deck (31):
O2 content = (equation )
O2 content = ( O2 binding capacity x saturation) + disolved O2 = (1.34 x Hb x Sa O2 ) + ( 0.003xPaO2)
SaO2 = arterial O2 saturation
PaO2= partial pressure of O2
( 0.003xPaO2) = dissolved oxygen
(1.34x Hb ) = oxygen binding capacity
normally 1 g Hb bind ... O2
normal amount of Hb in blood
cyanosis resutls when
deoxygenateed Hb > 5g /dl
O2 binding capacity (calculation and result )
O2 binding capacity = normal amount of Hb in blood x 1.34 ml = 15g/ dl x 1.34ml =20.1ml O2/dL
O2 binding capacity (result ) normally
Dereased Hb --> O2 content of arterial blood?
Dereased Hb --> O2 saturation
Dereased Hb --> arterial pO2
O2 delivered to tissues ( equation)
O2 delivered to tissues = cardiac output x O2 contain of blood
CO poisoining - Hb concntration ?
anemia - Hb concentration ?
polyctemia - Hb concentration ?
Co poisoning - % saturation of Hb ?
anemia - % saturation of Hb ?
polycethemia - % saturation of Hb ?
CO poisioning - dissolved O2 (PaO2) ?
anemia - dissolved O2 (PaO2) ?
polyethemia - dissolved O2 (PaO2) ?
anemia - total O2 content ?
Co poiosoning - total O2 content ?
pollycethemia - - total O2 content ?
CO vs O2 binding on Hb ( affinity?)
CO has x 200 grater affinity
Dissolved O2 in blood equation
0.003 x PaO2
What is the equation for oxygen content in the blood?
O2 content = (O2 binding capacity × percent saturation) + dissolved O2
A previously healthy patient develops blue lips and fingertips. What does this say about the value of her deoxygenated hemoglobin level?
Her deoxygenated hemoglobin must be >5 g/dL (this is cyanosis)
What is the normal value of the O2 binding capacity?
20.1 mL O2/dL
As Hb falls, what happens to each parameter (increase/decrease/unchanged): O2 content of arterial blood, O2 saturation, arterial PO2?
O2 content of arterial blood decreases, O2 saturation and arterial PO2 remain unchanged
• How do you calculate oxygen delivery to the tissues?
O2 delivery to tissues = cardiac output × O2 content of blood
A woman has CO poisoning. What are the likely levels of her Hb, %O2 saturation of Hb, dissolved O2 (PaO22 content?
Hb is normal, %O2 saturation of Hb is decreased (CO competes with O2), PaO2 is normal, and total O2 content is decreased