UMEM Educational Pearls

Hyperoxia in the Critically Ill

  • Oxygen is liberally administered to many critically ill patients, thereby exposing them to supranormal arterial oxygen levels.
  • Hyperoxia results in the formation of reactive oxygen species, which adversely affect the pulmonary, vascular, cnetral nervous, and immune systems.
  • Though the optimal PaO2 remains unknown, recent evidence indicates that hyperoxia is associated with increased mortality in post-cardiac arrest, CVA, acute coronary syndrome, and traumatic brain injury patients.
  • Take Home Point: Carefully titrate oxygen to the lowest tolerable level to meet the patient's needs.


Helmerhorst HJF, et al. Association between arterial hyperoxia and outcomes in subsets of critical illness: A systematic review, meta-analysis, and meta-regression of cohort studies. Crit Care Med 2015; 43:1508-19.