A Mixed Venous Blood Sample Obtained from a Pulmonary Artery

Multiple Choice

A mixed venous blood sample obtained from a pulmonary artery catheter sample has a PO₂ of 85 mm Hg and a hemoglobin saturation of 95%. Which of the following is likely?
1) The pulmonary artery catheter balloon was not deflated.
2) The sample was drawn from the proximal, not distal port.
3) The blood sample was withdrawn too quickly.

A) 1 and 2 only
B) 1 and 3 only
C) 2 and 3 only
D) 1, 2, and 3