Demystifying Lactate in the Emergency Department

Ann Emerg Med. 2020 Feb;75(2):287-298. doi: 10.1016/j.annemergmed.2019.06.027. Epub 2019 Aug 29.


The role of lactic acid and its conjugate base, lactate, has evolved during the past decade in the care of patients in the emergency department (ED). A recent national sepsis quality measure has led to increased use of serum lactate in the ED, but many causes for hyperlactatemia exist outside of sepsis. We provide a review of the biology of lactate production and metabolism, the many causes of hyperlactatemia, and evidence on its use as a marker in prognosis and resuscitation. Additionally, we review the evolving role of lactate in sepsis care. We provide recommendations to aid lactate interpretation in the ED and highlight areas for future research.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Acidosis, Lactic / etiology
  • Emergency Service, Hospital
  • Humans
  • Hyperlactatemia / chemically induced
  • Hyperlactatemia / etiology*
  • Lactic Acid / blood*
  • Lactic Acid / metabolism
  • Prognosis
  • Sepsis / blood
  • Sepsis / complications
  • Thiamine Deficiency / complications
  • Wounds and Injuries / complications


  • Lactic Acid