Background
Various automated compression device (ACD) have been adopted by emergency medical services (EMS) worldwide to ensure cardiopulmonary resuscitation (CPR) quality. We developed a new ACD with a manual adjustment function according to compression depth and rate. This study aimed to compare the CPR quality and chest injury caused between the new ACD and a conventional device (LUCAS, Physio-Control, Sweden).
Methods
A randomized experimental trial using each eight pigs for ACD and Lucas group were performed to compare the CPR quality, outcomes, and safety. After 1-minute of untreated electrical-induced ventricular fibrillation, followed by 8-minutes of basic life support, and 20-minutes of advanced cardiac life support including epinephrine infusion were provided under mechanical ventilation. Hemodynamic parameters were obtained and observed end-tidal CO2 (ETCO2) were continuously measured from endotracheal tube as study outcome. Mixed model analysis and repeated measure ANOVA were used to compare the difference of hemodynamic parameters and observed ETCO2. We examined the all pigs for gross pathologic findings (number of lung contusion, laceration, bone fracture, and hematoma in the thoracic cavity) after CPR procedures through open thoracotomy. 
Results
There was no significant difference for hemodynamic parameters such as mean arterial pressure, 29.4 mmHg in ACD group versus 35.3 mmHg in Lucas group (p-value= 0.39). Observed ETCO2 between ACD and Lucas group were 18.0 and 26.8 mmHg (p-value=0.24). Repeated measure ANOVA for observed ETCO2 did not show significant difference (17.6 versus 26.0, p-value= 0.29). The gross pathologic findings through open thoracotomy examination after CPR showed insignificant difference of injury number in chest cavity and wall (7.63 versus 9.38, p-value= 0.49).
Conclusions
Hemodynamic parameters and observed ETCO2 were slightly better in Lucas group than new ACD group. However, the statistical significances were not found in the porcine experimental mechanical models.

1 - evaluation of clinical efficacy and safety of a newly developed automated cardiopulmonary resuscitation device; a porcine cardiac arrest model