breathing machine

noun

: a device that assists breathing (as by keeping the air passages open) or maintains artificial respiration

He suffers from sleep apnea, so he uses a breathing machine.

—Dan Casey, The Roanoke (Virginia) Times

The team tried to put her on a breathing machine, but the pond water had damaged her lungs too severely for oxygen to reach her blood.

—Atul Gawande, The New Yorker