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 consumption 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 consumption is approximately

Quizplus · Accepted Answer

The clinical data shows that the patient has a PaO2 of 54 mm Hg (normal range: 75-100 mm Hg) and a SaO2 of 84% (normal range: 95-100%). This indicates that the patient is hypoxic and not delivering enough oxygen to tissues. To compensate for this, the patient's oxygen consumption would increase. Using the formula for oxygen consumption (VO2 = cardiac output x (CaO2 - CvO2)), we can estimate the patient's oxygen consumption. The patient's cardiac output is not provided in the clinical data, but a normal resting cardiac output is around 5 L/minute. For simplicity, we can assume this as the patient's cardiac output. The patient's CaO2 (arterial oxygen content) can be calculated as: CaO2 = (PaO2 x 0.003) + (SaO2 x hemoglobin x 1.34). Assuming a hemoglobin level of 15 g/dL, the patient's CaO2 would be approximately 17.6 ml/dL. Finally, the patient's CvO2 (venous oxygen content) is typically around 15 ml/dL. Plugging in the values, we get: VO2 = 5 L/minute x (17.6 - 15) ml/dL = 80 ml/minute or 380 ml O₂/minute. Therefore, the best choice is C.