Causes of Elevated Lactate

High lactate levels associated with worse prognosis in medical and trauma patients

• Level >2 mmol/L is abnormal
• Level >4 mmol/L suggests tissue hypoperfusion

Causes for elevation in lactate that is NOT related to shock

Inadequate O₂ delivery

• Severe dehydration
• Blood loss
• Severe anemia
• Hypoxemia
• CO prolonged exposure
• Trauma

Disproportionate O₂ demanc

• Hyperthermia
• Shivering
• Seizure`
• Strenuous exercise`

Inadequate O₂ use

• SIRS
• DM
• TPN
• HIV infection
• Medications:
  • Metformin
  • Salicyclate
  • Antiretrovirals
  • INH
  • Propofol
  • Cyanide

References

• Strehlow MC.Early identification of shock in critically ill patients. Emerg Med Clin North Am. 2010 Feb;28(1):57-66, vii. doi: 10.1016/j.emc.2009.09.006. [PubMed]
• Perera P et al. Rapid Ultrasound in SHock in the Evaluation of the Critically lll. EMCNA 2010; 28: 29-56. [PubMed]