Oxygen Delivery

Question 1

Delivery of Oxygen Equation

Answer 1

DO2=QxCaO2

Q=SVxHR

SV=Preload+Afterload+Contractility

CaO2=[1.34xHbgx(SaO2)] + Pa02 x 0.003

Question 2

Measuring O2 Delivery

Answer 2

Hemoglobin = 1.34 ml of oxygen
Ex. 1.34 x 15 (hgb) x 1.0 = 20 ml/dL
Simplify = 20mL/100mL = 0.2 mL
Standard adult = 5 L/min or 5000mL

0.2mL ox oxygen x 5000mL = 1000mL oxygen per minute.

Divide by 1.7m2 to account for BSA.

= O2/min/m2

Question 3

Fick Formula

Answer 3

Cellular Uptake of O2

Same as D02 but using Sv02 as a standard.

(1.34 x hbg (g/dL) x SvO2)

Question 4

What is the biggest aspect of oxygen delivery? (Possible Test Question)

Answer 4

ALWAYS Hemoglobin!

Question 5

Anaerobic Metabolism

Answer 5

1. Glycolysis - Pyruvate
2. Pyruvate - Lactic Acid
3. if O2 is low or not present, then lactic acid accumulates.

Question 6

Types of hypoxia

Answer 6

1. Hypoxic Hypoxia - Deficiency in alveolar exchange
2. hypemic hypoxia - reduction in O2 carrying capacity
3. Stagnant hypoxia - Obstructive shock, reduced cardiac output, PE, shock states.
4. histotoxic hypoxia - a result of poisoning or metabolic disorders such as cyanide, ETOH, or CO poisoning.