asphyxia vs lights out

asphyxia

noun
  • Loss of consciousness due to the interruption of breathing and consequent anoxia. 

  • Loss of consciousness due to the body's inability to deliver oxygen to its tissues, either by the breathing of air lacking oxygen or by the inability of the blood to carry oxygen. 

lights out

noun
  • Unconsciousness. 

How often have the words asphyxia and lights out occurred in a corpus of books? (source: Google Ngram Viewer )