In practice it clearly isn't airtight, otherwise the foam wouldn't have been able to end up inside patients. Not sure whether it would have been easier to desig

In practice it clearly isn't airtight, otherwise the foam wouldn't have been able to end up inside patients. Not sure whether it would have been easier to design an airtight circui, or to ensure that the insulation is wrapped in something that effectively separates it from the air circuit. Either way, this is pretty shitty. These machines are pretty expensive (and someone makes a hefty profit on them, because most patients rent theirs). Seems like the least they could have done was make sure it was worth the money.