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.
Similar to a CPAP machine, A BiPAP machine is a non-invasive form of therapy for patients suffering from sleep apnea. Both machine types deliver pressurized air through a mask to the patient's airways.