Effective lactate clearance is associated with improved outcome in post-cardiac arrest patients

Abstract

Early, effective lactate clearance has been shown to be associated with improved mortality in patients with trauma, burns, and sepsis. We investigated whether early, high lactate clearance was associated with reduced mortality in post-cardiac arrest patients. We performed a retrospective analysis of post-cardiac arrest patients in an urban emergency department. Inclusion criteria included pre-hospital cardiac arrest patients over the age of 18. Exclusion criteria were traumatic arrest, successful resuscitation prior to the arrival of emergency medical services, and cardiac arrest in the presence of pre-hospital providers. Primary endpoints consisted of survival to 24h and survival to hospital discharge. A total of 79 patients were analyzed with a mean age of 64+/-17 and mean APACHE II score of 37.7+/-5. Of the 79 patients, 27 (34%) died within 24h and 66 (84%) died during the hospital course. The mean initial lactate level for the overall group was 15+/-5.2mmol/dl with a mean lactate of 14.4+/-5.1mmol/dl in the survivors and 16+/-5.3mmol/dl in the non-survivors (p>0.05). Lactate clearance at both 6 and 12h was significantly higher for both 24-h and overall in-hospital survival (p<0.05). A multivariable analysis showed that high lactate clearance at 12h was predictive of 24-h survival (p<0.05). Early, effective lactate clearance is associated with decreased early and overall in-hospital mortality in post-cardiac arrest patients. These findings suggest that post-arrest tissue hypo-perfusion plays in an important role in early as well as overall mortality.