Abstract 91: Association of Blood Lactate and Ammonia with Neurologically Intact Survival in Patients After Out-of-Hospital Cardiac Arrest: SOS-KANTO Study
Introduction: Blood levels of lactate and ammonia can potentially reflect the severity of ischemic injury in patients after out-of-hospital cardiac arrest (OHCA).
Hypothesis: Blood lactate and ammonia have high prognostic values in patients who were successfully resuscitated after OHCA and admitted to the hospital.
Methods: Between 2012-13, we enrolled 16,452 CA patients in Kanto-area, Japan, in the study of SOS-KANTO registry. Adult (≥18 years) patients, resuscitated from non-traumatic OHCA and admitted to the hospital, were included. Blood samples were obtained and levels of lactate and ammonia were measured in the emergency room. We used the cutoff values of 12.0 mmol/L for lactate and 100 μmol/L for ammonia based on our previous study. All therapeutic indications were blinded from those cutoff values. Patients were classified into two groups according to their cerebral performance category (CPC) at 3 months after CA, favorable (CPC 1-2) and poor (CPC3-5) outcome groups. Logistic regression analysis was used to calculate adjusted odds ratio to favorable outcome.
Results: Of 3,011 included patients, 2,016 cases were valid for lactate and 1,442 for ammonia analysis, respectively. A total of 912 patients had both results recorded and served as the study subjects. The number of favorable outcome groups was 130 (14.3%). Odds ratio [95% confidence interval (CI)] for favorable outcome of lactate (≤12.0 mmol/L) and ammonia (≤100 μmol/L) were 5.3 [3.1-8.9, p<0.001] and 6.6 [4.0-11.0, p<0.001], respectively. The positive predictive values of favorable outcome were 86.2% and 85.4%, and the negative predictive values were 45.9% and 53.2%, respectively. Adjusted odds ratio [95% CI] of lactate (3.8 [2.1-7.0], p<0.001) and ammonia (4.1 [2.3-7.4], p<0.001) were higher than those of shockable rhythm (2.1 [1.3-3.6], p=0.005), cardiac origin (3.3 [1.9-5.5], p<0.001), bystander CPR (3.0 [1.7-5.2], p<0.001), and witness by bystander (0.96 [0.5-1.9], p=0.911).
Conclusions: The predictive values of lactate and ammonia were considered to be higher than pre-hospital information. These biomarkers have utility as predictors after resuscitation as directing therapeutic decision-making on post-cardiac arrest care and defining optimal populations for study enrolled.
Author Disclosures: K. Shinozaki: None. S. Oda: None. S. Masaru: None. A. Sakurai: None. Y. Tahara: None. Y. Naohiro: None. K. Nagao: None. A. Yaguchi: None. N. Morimura: None.
- © 2014 by American Heart Association, Inc.