The victim was bound upon this wheel, on his knees, with his hands behind his back.
A continuous positive airway pressure (CPAP) machine was initially used mainly by patients for the treatment of sleep apnea at home, but now is in widespread use across intensive care units as a form of ventilation.
You use CPAP at home every night while you sleep. The CPAP machine will have one of the following: 1  A mask that covers your nose and mouth.  A mask that covers your nose only-called nasal continuous positive airway pressure, or NCPAP (this type of mask is most common).