CPAP and BIPAP machines don't make the kind of noise used in this episode. The machines are actually quite silent. And they don't have alarms on them either. The kinds of alarms heard are seen on hospital ventilators. Not on CPAP machines.
Mike misquotes an old saying. He says: "it's colder than a well diggers ass out there". The correct saying is: it's colder than a well digger ankles. It's ankles because the ankles are low and get cold first, and are more likely to be in the water. So what? People misquote things all the time. It's done for comedic purposes.