Multi-center observational study of the association between ventilation and cardiac arrest outcome

Ut Southwestern Medical Center, Dallas TX

Investigators

Abstract

Project Summary/Abstract Introduction: Out-of-hospital cardiac arrest (OHCA) is a major public health problem that affects over 350,000 adults in the US each year. Survival from OHCA remains unacceptably low despite promising advances over the last decade. During cardiac arrest, all circulation stops. Cardiopulmonary resuscitation (CPR) combines chest compressions (circulation) with lung inflation (ventilation) to restore perfusion and oxygenation to the body. During the past decade, research focused on measuring chest compressions during CPR has led to improvements in performance of chest compressions and improved clinical outcomes. However, ventilation has long been a “neglected parameter” in CPR research, in part, because measuring ventilation during OHCA and CPR is difficult. To address this problem, we developed a novel method for measuring ventilation during CPR using thoracic bioimpedance (electrical resistance), which can be monitored through defibrillator pads placed during CPR. Our studies showed that lung inflation does not occur in most ventilation attempts with use of a bag-mask (BM) device during standard 30:2 CPR. We now have developed and validated a machine-learning automated program that can measure ventilation during continuous chest compression (CCC) CPR. Objectives: The objectives of this study are to facilitate trial design development through measurement and analysis of ventilation metrics using data from a large, comprehensive OHCA trial. Methods: The study will use data from one of the largest, comprehensive OHCA multi-center clinical trial in the world. The ROC CCC Trial database includes CPR resuscitation metrics, patient outcomes, and access to defibrillator bioimpedance recordings. A validated method to identify bioimpedance ventilation waveforms has been programmed into an automated computer algorithm, which will extract ventilation data from defibrillator- monitor bioimpedance recordings from approximately 7,600 patients from seven ROC sites that participated in the CCC Trial. Ventilation data will be matched with clinical data. Specific Aims: 1) To determine ventilation frequency, incidence, bioimpedance waveform amplitude, and inspiratory and expiratory times from the CCC CPR defibrillator and clinical files and 2) determine association of variable with types of airway devices 3) To determine the association of BVM ventilation frequency, incidence, and fraction with survival outcomes in the CCC CPR group and association with airway devices and compare it with the 30:2 CPR group. Significance: The results may provide evidence for a paradigm shift of our view regarding the importance of ventilation during CPR and impact CPR training and guidelines. It will provide support for developing trial design to test ways to improve ventilation during CCC and 30:2 CPR.