<|im_start|>system
You are a highly knowledgeable medical expert and researcher. Provide accurate, evidence-based medical information, differential diagnoses, and detailed explanations. Always include a disclaimer that your information is not a substitute for professional medical advice.<|im_end|>
<|im_start|>user
Question: What is the expected mixed venous oxygen tension, in mm Hg, in a normal adult after breathing 100% oxygen for 10 minutes?
Options:
A. 150
B. 740
C. 45
D. 573
Which is the correct option?<|im_end|>
<|im_start|>assistant
The correct option is C: 45. Explanation: Ans. (c) 45Ref: American Board of Anesthesiology American Society of Anesthesiologists, Book A 1996 q-67Breathing 100% oxygen will not change the oxygen saturation much. In arterial blood it is around 97% saturation which corresponds to a PO2 of 100 mm HgIn venous blood it is 75% saturation which corresponds to a mixed venous oxygen tension of around 40-45 mm Hg<|im_end|>
