The la salle assessment of return of spontaneous circulation in adult cardiac arrest: A case control study (the LASARUS study)

Background: Return of spontaneous circulation (ROSC) is the first crucial phase to be achieved in cardiac arrest resuscitation. To date, there is no valid tool available to prognosticate ROSC in adult, non-traumatic out-ofhospital cardiac arrest (OHCA) patients. Objective: To develop a model of clinical scoring system predicting ROSC in adult, non-traumatic OHCA patients – the LASARUS score. Methods: We retrieved complete medical records of adult, non-traumatic OHCA patients between January 2009 and December 2013. Univariate analysis and logistic regression analysis were subsequently performed, providing a value for each variable in the scoring system. Receiver Operating Characteristic (ROC) curve was then done to determine the best cut-off score. Results: Of the 370 patients, initial ECG rhythm, witnessed arrest, bystander cardio pulmonary resuscitation (CPR), interval between collapse and CPR initiation were variables associated with ROSC. Logistic regression analysis assigned a value of four (4) for initial ECG rhythm, two (2) for bystander CPR, two (2) for interval between collapse and CPR initiation, and one (1) for witnessed arrest. ROC curve analysis showed three (3) as the best cut-off score (accuracy 0.741, 95% CI: 0.689-0.792, P \u3c 0.001). The cumulative score was divided into two groups (0-2 and ≥3) with the rate of ROSC in each group was 9.65% and 47.26% respectively (P \u3c 0.001). Conclusion: The LASARUS score demonstrates a preliminary model of clinical scoring system predicting ROSC in adult, non-traumatic OHCA