Lactate Clearance Portends Better Outcomes after Cardiac Arrest
Clinical question: Is greater lactate clearance following resuscitation from cardiac arrest associated with lower mortality and better neurologic outcomes?
Background: Recommendations from the International Liaison Committee on Resuscitation for monitoring serial lactate levels in post-resuscitation patients are based primarily on extrapolation from other conditions such as sepsis. Two single-retrospective analyses found effective lactate clearance was associated with decreased mortality. This association had not previously been validated in a multicenter, prospective study.
Study design: Multicenter, prospective, observational study.
Setting: Four urban, tertiary-care teaching hospitals.
Synopsis: Absolute lactate levels and the differences in the percent lactate change over 24 hours were compared in 100 patients who suffered out-of-hospital cardiac arrest. Ninety-seven percent received therapeutic hypothermia, and overall survival was 46%. Survivors and patients with a good neurologic outcome had lower lactate levels at zero hours (4.1 vs. 7.3), 12 hours (2.2 vs. 6.0), and 24 hours (1.6 vs. 4.4) compared with nonsurvivors and patients with bad neurologic outcomes.
The percent lactate decreased was greater in survivors and in those with good neurologic outcomes (odds ratio, 2.2; 95% confidence interval, 1.1–4.4).
Nonsurvivors or those with poor neurologic outcomes were less likely to have received bystander CPR, to have suffered a witnessed arrest, or to have had a shockable rhythm at presentation. Superior lactate clearance in survivors and those with good neurologic outcomes suggests a potential role in developing markers of effective resuscitation.
Bottom line: Lower lactate levels and more effective clearance of lactate in patients following cardiac arrest are associated with improved survival and good neurologic outcome.
Citation: Donnino MW, Andersen LW, Giberson T, et al. Initial lactate and lactate change in post-cardiac arrest: a multicenter validation study. Crit Care Med. 2014;42(8):1804-1811.
