Study #1 (Oxygen Transport Studies)
A 63-year-old woman with chronic obstructive pulmonary disease demonstrates the following clinical data:

-In reference to the clinical data presented in this , the patient's oxygen extraction ratio is approximately

Question

Study #1 (Oxygen Transport Studies)
A 63-year-old woman with chronic obstructive pulmonary disease demonstrates the following clinical data:
 
-In reference to the clinical data presented in this , the patient's oxygen extraction ratio is approximately

Quizplus · Accepted Answer

To calculate the oxygen extraction ratio (OER), the formula is: (CaO2 - CvO2)/CaO2, where CaO2 is the arterial oxygen content and CvO2 is the mixed venous oxygen content. 
Using the data given: 
CaO2 = (0.3 x 13.6) + 11.9 = 15.07 mL/dL 
CvO2 = (0.3 x 8.1) + 6.9 = 8.52 mL/dL 
OER = (15.07 - 8.52)/15.07 = 0.449 or approximately 0.29 (rounded to the nearest hundredth). 
Thus, the answer is C.