Injuries Associated with Prehospital CPR Provided by Professionals and Non-Professionals in Bangkok EMS

Background: This study is to concentrate on adverse outcomes of CPR in out-of-hospital cardiac arrest (OHCA) among different performers that are trained first responders, professional practitioners, and automated devices by exploring types of injuries and comparing between datasets. It is also to find out potential contributing factors for each injury which display statistical significance. Methods: Forensic autopsy data from a single center covering almost half of Bangkok and her outskirts which were performed during October 2020 to January 2021 were retrospectively collected and analyzed. The data were divided into 3 groups, namely, TFR (trained first responder), PP (professional practitioner), and Auto (automated device i.e. LUCAS system). Thoraco-abdominal injuries were recorded including soft tissue, bone and internal viscera. Factors including age, BMI, sternal length (SL) and chest circumference (CC) were categorized in each injury. Statistical comparison between groups and analysis for significant factors were performed. Results: A total number of 158 cases reported as OHCA with exclusion of thoraco-abdominal injuries were recruited. The most commonly found as a hallmark of CPR injuries are chest wall fractures especially those of ribs (65.7%). Bilateral anterior rib fractures are more common than unilateral. Significantly associated factors to rib fractures are age and BMI. Other injuries are sternal fractures, lung contusions and lacerations, epicardial and subendocardial hemorrhages, cardiac contusions, liver lacerations, and pancreatic and splenic hemorrhages. No statistical difference between injuries generated by trained first responders and professional practitioners. LUCAS devices show higher incidence of injuries than manual CPR. Conclusion: This study may provide useful information for clinicians to investigate and monitor potential CPR complications as well as for forensic physicians to concern the injuries possibly caused by CPR.