asphyxia vs somnolence

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. 

somnolence

noun
  • A state of drowsiness or sleepiness. 

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