Abstract
BACKGROUND: Early prognostication of out-hospital cardiac arrest (OHCA) patient's during cardiopulmonary resuscitation (CPR) is challenging and based on a combination of factors. The aim of this study was to assess the prognostic value of cerebral oximetry (rSO(2)), infrared automated pupillometry and end-tidal CO(2) (EtCO(2)) alone or in combination for patients with OHCA. METHODS: A prospective multicenter cohort study in 3 French prehospital mobile intensive care units was performed. Adult patients with a presumed medical OHCA were included. Measurements were made at medical team arrival every 5 min for at least 15 min. The primary endpoint was the prognostic value of the parameters for survival at hospital admission. RESULTS: Of the 112 patients included and analyzed, 19 (17%) survived to hospital admission. Initial values for survival at hospital admission differed for rSO(2) (alive: median: 30.0% (Q1: 19.0; Q3: 43.0) vs dead: 15.0% (15.0; 22.0), p < 0.001) and for EtCO(2) (43.5 mmHg (26.8; 56) vs. 22.0 mmHg (15.0; 36.5), p = 0.006) in contrast to pupillometry values (6.0% (2.0; 11.5) vs. 3.0% (0; 7.5), p = 0.10). Initial rSO(2) alone had an AUC of 0.74 (95% CI 0.59-0.88) and EtCO(2) alone provide an AUC of 0.77 (95% CI 0.64-0.89). Pupillometry alone had an AUC of 0.65 (95% CI 0.51-0.79). In combination, initial EtCO(2) plus initial rSO(2) provided an AUC of 0.85 (95% CI 0.73-0.96). CONCLUSION: During OHCA, rSO(2) and EtCO(2) could be predictive factors for survival at hospital admission with an acceptable discrimination, and their prognostic value was improved when both factors were combined. Further studies are needed to clarify the prognostic value of rSO(2), EtCO(2) and pupillometry for survival at hospital admission.