14 years ago my wife was in critical condition with Severe Acute Pancreatitis and the ventilator wasn’t getting enough air into her longs. The hospital switched to a then experimental ventilator for infants that gave shallow but rapid bursts of air and that did the trick until her lungs recovered.
That's amazingly painful.
I would have gone into shock and died without morphine.
As it was? Let's just say there's something special about watching the paramedics work on you from somewhere near the ceiling...
High frequency(frequency of “puffs” not sound) oscillating ventilator...we use them from time to time in our ICU. it keeps the sacks open and compensates if the diaphragm is stiff or not working well, which in your wife’s case might have been the issue until the swelling and inflammation from the pancreatitis subsided. If diaphragmatic function is impaired a normal ventilator would have difficulties using it’s “pull release” function to move air as the diapragm would be still or blocked due to abdominal ascites and swelling related to the pancreatitis. So the oscillating vent was used; fortunately for your wife it saved her. I trust she is doing okay today?