<unk>  is the sensation of feeling faint, lightheadedness and muscular weakness without actually losing consciousness. The<unk>  stage may occur for only a few seconds as a prodrome before losing consciousness.<unk>  is most often due to cardiovascular etiology.
Presyncope
Syncope
Sleep paralysis
Cough syncope
Apnea
Laryngospasm
Trepopnea
Respiratory arrest