Neurological Outcome of Chest Compression-Only Bystander CPR in Asphyxial and Non-Asphyxial Out-Of-Hospital Cardiac Arrest: An Observational Study

Abstract

Background: According to guidelines and bystander skill, two different methods of cardiopulmonary resuscitation (CPR) are feasible: standard CPR (S-CPR) with mouth-to-mouth ventilations and chest compression-only CPR (CO-CPR) without rescue breathing. CO-CPR appears to be most effective for cardiac causes, but there is a lack of evidence for asphyxial causes of out-of-hospital cardiac arrest (OHCA). Thus, the aim of our study was to compare CO-CPR versus S-CPR in adult OHCA from medical etiologies and assess neurologic outcome in asphyxial and non-asphyxial causes.

Methods: Using the French National OHCA Registry (RéAC), we performed a multicenter retrospective study over a five-year period (2013 to 2017). All adult-witnessed OHCA who had benefited from either S-CPR or CO-CPR by bystanders were included. Non-medical causes as well as professional rescuers as witnesses were excluded. The primary end point was 30-day neurological outcome in a weighted population for all medical causes, and then for asphyxial, non-asphyxial and cardiac causes.

Results: Of the 8 541 subjects included for all medical causes, 6 742 had a non-asphyxial etiology, including 5 904 of cardiac causes, and 1 799 had an asphyxial OHCA. Among all subjects, 8.6%; 95% CI [8.1-9.3] had a good neurological outcome (i.e. cerebral performance category of 1 or 2). Bystanders who performed S-CPR began more often immediately (89.0%; 95% CI [87.3-90.5] versus 78.2%; 95% CI [77.2-79.2]) and in younger subjects (64.1 years versus 65.7; p < 0.001). In the weighted population, subjects receiving bystander-initiated CO-CPR had an adjusted relative risk (aRR) of 1.04; 95% CI [0.79-1.38] of having a good neurological outcome at 30 days for all medical causes, 1.28; 95% CI [0.92-1.77] for asphyxial etiologies, 1.08; 95% CI [0.80-1.46] for non-asphyxial etiologies and 1.09; 95% CI [0.93-1.28] for cardiac-related OHCA.

Conclusions: We observed no significant difference in neurological outcome when lay bystanders of adult OHCA initiated CO-CPR or S-CPR, whether the cause was asphyxial or not.

Key words:

• basic life support
• cardiopulmonary resuscitation
• out-of-hospital cardiac arrest
• chest compression-only
• mouth-to-mouth resuscitation

Declarations

Ethics Approval and Consent to Participate

This study was approved as a medical registry assessment by the French Advisory Committee on Information Processing in Health Research (CCTIRS), and by the French National Data Protection Commission (CNIL, authorization number; 910946). This study was approved as a medical registry assessment without the requirement for patient consent.

Consent for Publication

Not applicable

Availability of Data and Materials

Data are available on request to the corresponding author.

Competing Interests

The authors declare that they have no competing interests.

Funding

The RéAC registry is supported by the French Society of Emergency Medicine (SFMU), a patient foundation – Fédération Française de Cardiologie, the Mutuelle Générale de l’Education Nationale (MGEN), the University of Lille and the Institute of Health Engineering of Lille.

Authors' Contributions

FJ and QLB had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. FJ and QLB elaborated the conception and design of the study. HH and VB collected the data. FJ, JR, ND, CLC and QLB contributed to the analysis and interpretation of the data. FJ wrote the first draft of the paper, with all other authors making important critical revisions. All authors have read and approved the final version of the manuscript.