Study Finds Blood Lactate and Lactate Clearance Important Prognostic Variables for Mortality in Trauma Patients

Early after trauma, changes in blood lactate over time, defined as lactate clearance, provide additional information predicting mortality in trauma patients according to a study from the December issue of Anesthesiology. Researchers in Paris determined lactate clearance along with the initial blood lactate levels and early injury severity scores provide additional predictive information to best treat patients.

Trauma is the third overall cause of death and the first before 40 years of age.¹ An estimated 80 percent of deaths occur within the first 48 hours after trauma, and hemorrhage is one of the leading contributors to trauma death.² Treatment of trauma includes recognizing and treating hemorrhage early, as well as limiting the amount shock.

“Hemorrhage dampens oxygen delivery to organs and this, in turn, leads to lactate production,” said study author Mathieu Raux, M.D., Ph.D. “However, this phenomenon can be difficult to diagnose in trauma patients. Our study aimed to demonstrate whether blood lactate and lactate clearance levels at the time of arrival in a trauma center predict massive hemorrhage, injury severity, requirement for emergency procedures and mortality.”

About the Study
Researchers measured blood lactate levels in 586 patients admitted to a trauma center:

• Fifty-six percent had elevated blood lactate upon admission
• Sixty-four percent had elevated blood lactate two hours after admission
• Forty-nine percent had elevated blood lactate four hours after admission

The association of initial blood lactate levels and lactate clearance with mortality was tested with triage scores and the Trauma Related Injury Severity Score (TRISS) as a reference standard and reclassification method.

The research discovered that lactate clearance provides additional predictive information to initial blood lactate levels, triage scores and the reference TRISS score. In addition, the research identified an increase in mortality that correlated with an increase in the initial blood lactate level.

“We believe lactate clearance is an important and independent prognostic variable that should be incorporated in future decision schemes for the resuscitation of trauma patients,” continued Dr. Raux.

For more information, visit the Anesthesiology website at anesthesiology.org.

¹Murray CJL, Lopez AD. Mortality by cause for eight regions of the world: Global Burden of Disease Study. Lancet 1997; 349: 1269-76.
²Sauaia A, Moore FA, Moore EE, Moser KS, Brennan R, Read RA, Pons PT. Epidemiology of trauma deaths: a reassessment. J Trauma 1995; 38:185-93.