You lay the patient down and achieve surgical anesthesia quickly. The obstetricians begin working but because of the large pannus, they ask you to put the patient in steep Trendelenberg and have two nurses hold back the pannus as they work. Soon the patient becomes hypotensive. You run in fluids wide open and put a roll under the patient's right back to take pressure off the vena cava. The surgeons are getting into some blood loss, but not enough to explain the hypotension. She continues to remain hypotensive but is not particularly tachycardic. You ask her how she feels and she starts complaining of nausea and dyspnea. Her respiratory rate drops to 10, then 8, then 6. You end up intubating her emergently.
Challenge: What do you think happened?
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