sustained return of spontaneous circulation following out-of-hospital cardiac arrest; developing a predictive model based on multivariate analysis

Introduction: identifying the predictive factors of sustained return of spontaneous circulation (rosc) following out-of-hospital cardiac arrest (ohca) will be helpful in management of these patients. this study aimed to develop a predictive model in this regard. methods: in a retrospective observational study, data of adult patients with ohca, were collected from vajira emergency medical services patient care report. multiple logistic regression analysis with a regression coefficient was used to develop a predictive score for a sustained rosc at the scene. area under the receiver operating characteristic (roc) curve (auc) was used to validate the accuracy of the predictive score for a sustained rosc. results: independent factors associated with a sustained rosc included cardiopulmonary resuscitation (cpr) duration < 30 min (adjusted odds ratio (aor)= 5.05, 95% confidence interval (ci): 3.34–7.65; p < 0.001); advanced airway management with an endotracheal tube (aor= 3.06, 95% ci: 1.77–5.31; p < 0.001); advanced airway management with laryngeal mask airway (aor= 3.42, 95% ci: 1.02–11.46; p = 0.046); defibrillation (aor = 2.05, 95% ci: 1.31–3.2; p = 0.002); capillary blood glucose (cbg) level < 150 mg% (aor= 1.95, 95% ci: 1.05–3.65; p = 0.035); cbg at least 150 mg% (aor= 2.87, 95% ci: 1.56–5.29; p = 0.001); pupil reflex (aor = 2.96, 95% ci: 1.1–7.96; p = 0.032); and response time at most 8 min (aor= 1.66, 95% ci: 1.07–2.57; p = 0.023). these were developed into the pupil reflex, response time, advanced airway management, defibrillation, cbg, and cpr duration (prad-ccpr) score. the most accurate cutoff point of score using youden’s index was ≥ 6 with auc of 0.759 (95% ci: 0.715–0.802; p < 0.001), sensitivity of 62.0% (95% ci: 51.2–71.9%), specificity of 75.7% (95% ci: 69.4–81.2%), positive predictive value of 51.8% (95% ci: 40.9–62.3%), and negative predictive value of 79.5% (95% ci: 73.5–84.6%). conclusion: an optimal prad-ccpr score of ≥ 6 provides an acceptable accuracy of 0.759 with sensitivity of 62.0% and specificity of 75.7% in prediction of sustained rosc following ohca. this predictive score might help cpr commanders to prognosticate the outcome of patients with ohca at the scene.