• The anaesthetic agent whose use may lead to diffusion hypoxia include?
  A. nitrous oxide
  B. halothane
  C. ethylene oxide
  D. sevoflurane
  
  Ans: A) Nitrous oxide
  Ref: K.D.Tripathi, 4th Ed, Pg-346
  
  Explanation -
  
  When Nitrous oxide is discontinued following prolonged use in anaesthesia, due to its low blood solubility, there is rapid diffusion of Nitrous oxide into alveoli and dilution of the alveolar air.
  Due to this, there is much reduction in the partial pressure of oxygen in the alveoli
  The resulting hypoxia is known as Diffusion Hypoxia
  
  Prevention - It can be prevented by

1) Continuing 100% oxygen inhalation for a few minutes after stopping nitrous oxide (so that the partial pressure of oxygen gets raised within the alveoli), instead of directly starting AIR