HI folks, here is a Twitter case discussion we had last night on patient with flash pulmonary oedema, rapid AF and critical aortic stenosis awaiting surgery.
[View the story “Crashing pulmonary oedema patient in rapid AF (TAKE 2) ” on Storify]
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In memory of Dr John Hinds
Prehospital and Retrieval Medicine - THE PHARM dedicated to the memory of Dr John Hinds 
From the story, new onset afib. Rapid A.fib sounds like the root cause of the lowBP and pulmonary edema. I think my input would be max Bipap settings (epap~20 cmh2o, 100%o2) and try cardioversion.
If above buys you a bit of room on sats, I’d advocate an approach like Scott posted on G+ a while ago: ETT fed part way into iLMA and cuff inflated, bronch adaptor hooked to Bipap. Insert LMA/ett combo, then can pass a bougie or bronchoscope through cords via adaptor while still giving pos. pressure and o2. Advance ETT over bougie/bronch without interrupting pressure/ox.
However, if sats stay 70s, no time for fancy stuff… RSI with neck prepped.