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.
CPAP only works when you use it. Most CPAP problems can be solved. If you are experiencing problems using CPAP talk to your doctor as there may be a workable solution. If your CPAP problems cannot be resolved, you may need to try an alternative such as an oral appliance or, in severe cases, surgery.