The Prognostic Usefulness of the Lactate/Albumin Ratio for Predicting Clinical Outcomes in Out-of-Hospital Cardiac Arrest: a Prospective, Multicenter Observational Study (koCARC) Study

Background and Purpose: We aimed to evaluate the lactate/albumin ratio (LAR) to identify its significance as a prognostic marker for favorable neurologic outcome and survival in patients with return of spontaneous circulation after out-of-hospital cardiac arrest (OHCA). Based on the LAR and multiple parameters, we developed new nomograms and externally validated the tools. Methods: We conducted an observational study using a prospective, multicenter registry of out-of-cardiac arrest resuscitation provided by the Korean Cardiac Arrest Research Consortium registry from October 2015 to June 2017. Results: A total of 524 patients were included in this study. An increased LAR was significantly associated with decreased favorable neurologic outcomes (odds ratio [OR] 0.787; 95% confidence interval [CI], 0.630-0.983;P = 0.035) and survival at discharge (OR 0.744; 95% CI, 0.638-0.867;P < 0.001). The areas under the curve (AUCs) for predicting neurologic outcome and survival to discharge using the LAR were 0.824 (P < 0.001) and 0.781 (P < 0.001), respectively. An LAR value of more than the optimal cutoff values of 2.82 and 3.62 could significantly improve prediction of decreased favorable neurologic outcome and survival to discharge, respectively. We constructed nomograms based on the multivariate logistic model. The model for predicting favorable neurologic outcomes and survival discharge had AUCs of 0.927 (P < 0.001) and 0.872 (P < 0.001), respectively. Conclusion: The prognostic performance of the LAR was superior to a single measurement of lactate for predicting favorable neurologic outcomes and survival to discharge after OHCA. The newly developed nomograms can provide rapid prediction of probability of clinical outcomes.