Positional asphyxia occurs when a restrained person's body position interferes with their ability to breathe. It can happen quickly, sometimes in under 6 minutes. Several factors increase the risk, such as obesity, drug use, agitation, being prone or face down which restricts chest movement and lung expansion. Those with Prader-Willi syndrome are at especially high risk due to obesity, weak chest muscles, and other anatomical and medical factors. Signs of distress during restraint require immediately ending the hold and seeking medical attention.