Trends in survival from out-of-hospital cardiac arrest with a shockable rhythm and its association with bystander resuscitation: a retrospective study.

OBJECTIVE: Over 300 000 cases of out-of-hospital cardiac arrests (OHCAs) occur each year in the USA and Europe. Despite decades of investment and research, survival remains disappointingly low. We report the trends in survival after a ventricular fibrillation/pulseless ventricular tachycardia OHCA, over a 13-year period, in a French urban region, and describe the simultaneous evolution of the rescue system. METHODS: We investigated four 18-month periods between 2005 and 2018. The first period was considered baseline and included patients from the randomised controlled trial 'DEFI 2005'. The three following periods were based on the Paris Sudden Death Expertise Center Registry (France). Inclusion criteria were non-traumatic cardiac arrests treated with at least one external electric shock with an automated external defibrillator from the basic life support team and resuscitated by a physician-staffed ALS team. Primary outcome was survival at hospital discharge with a good neurological outcome. RESULTS: Of 21 781 patients under consideration, 3476 (16%) met the inclusion criteria. Over all study periods, survival at hospital discharge increased from 12% in 2005 to 25% in 2018 (p<0.001), and return of spontaneous circulation at hospital admission increased from 43% to 58% (p=0.004).Lay-rescuer cardiopulmonary resuscitation (CPR) and telephone CPR (T-CPR) rates increased significantly, but public defibrillator use remained limited. CONCLUSION: In a two-tiered rescue system, survival from OHCA at hospital discharge doubled over a 13-year study period. Concomitantly, the system implemented an OHCA patient registry and increased T-CPR frequency, despite a consistently low rate of public defibrillator use.

Insufficient quality of public automated external defibrillator recordings in the greater Paris area, a descriptive study.

BACKGROUND: Western countries report a significant increase in the proportion of patients who experience out-of-hospital cardiac arrests (OHCAs) and benefit from a public automated external defibrillator (pAED) before the arrival of rescue teams. However, recordings of devices recovered after resuscitation are of variable quality. Analysis of these data may inform decisions of whether to implement an internal defibrillator for survivors, and provide useful information about the performance of pAED algorithms and the actions of bystanders. OBJECTIVE: To investigate the quality of the information recorded by pAEDs during OHCAs in the Paris area. METHODS: pAED files used for some of the 8629 OHCAs that occurred in the greater Paris area between 1 January 2017 and 31 April 2019 on the day of the arrest were collected. The presence and accuracy of 23 factors required to interpret the recording was noted, including readability of the ECG, the presence of an impedance curve and the accuracy of the date and time. The recordings were analysed to assess the diagnostic and therapeutic performance of the pAEDs used. RESULTS: A total of 258 patients with an OHCA received assistance from a pAED, and 182 recordings were recovered. The pAEDs were made by 12 different manufacturers. Data extraction required eight different transmission modes and 16 software programmes; recordings were of highly heterogeneous quality. Two per cent of the recordings were of such poor quality that they were not interpretable. Among the 98% remaining, only 43% included a thoracic impedance curve, 34% the intensity of the shocks delivered and 8% the patient name. The date and time were accurate in 68% and 48% of recordings, respectively. The pAEDs had 87.6% (95% CI 83.7% to 91.0%) sensitivity and 99.5% (99.5% to 99.5%) specificity for defibrillating shockable rhythms (positive predictive value 98.2% (96.4% to 99.0%), negative predictive value 96.4% (95.3% to 96.8%)). The absence of important variables prevented the analysis of approximately half of the inappropriate decisions made by pAEDs. CONCLUSION: Collection of pAED recordings is a major challenge. Their analysis is compromised by heterogeneity and poor quality (incomplete maintenance records, patient details and logs). AED recordings are currently the most relevant resource to track pAED performance and bystander practices. The quality of these recordings needs to improve.