Design of the circulation improving resuscitation care (CIRC) trial: a new state of the art design for out-of-hospital cardiac arrest research

Lerner, E. Brooke and Persse, David and Souders, Chris and Sterz, Fritz and Malzer, Reinhard and Lozano, Michael and Westfall, Mark and Brouwer, Marc A. and Grunsven, Pierre M. van and Whitehead, Anne and Olsen, Jan-Aage and Herken, Ulrich R. and Wik, Lars (2011) Design of the circulation improving resuscitation care (CIRC) trial: a new state of the art design for out-of-hospital cardiac arrest research. Resuscitation, 82 (3). pp. 294-299. ISSN 1873-1570

Abstract

Purpose Mechanical chest compression devices, such as the AutoPulse®, have been developed to overcome problems associated with manual CPR (M-CPR). Animal and human studies have shown that AutoPulse CPR improves hemodynamic parameters over M-CPR. However, human studies conducted in the prehospital setting have conflicting results as to the AutoPulse's efficacy in improving survival. The Circulation Improving Resuscitation Care (CIRC) Trial is designed to evaluate the effectiveness of integrated AutoPulse-CPR (iA-CPR) (i.e., M-CPR followed by AutoPulse®-CPR) in a randomized controlled trial that addresses methodological issues that may have influenced the results of previous studies. Methods This paper describes the methodology of the CIRC trial. Results Unlike previous trials the CIRC trial studies iA-CPR where emphasis is placed on reducing “hands-off” time. The trial has six unique features: (1) training of all EMS providers in a standardized deployment strategy that reduces hands-off time and continuous monitoring for protocol compliance. (2) A pre-trial simulation study of provider compliance with the trial protocol. (3) Three distinct study phases (in-field training, run-in, and statistical inclusion) to minimize the Hawthorne effect and other biases. (4) Monitoring of the CPR process using either transthoracic impedance or accelerometer data. (5) Randomization at the subject level after the decision to resuscitate is made to reduce selection bias. (6) Use of the Group Sequential Double Triangular Test with sufficient power to determine superiority, inferiority, or equivalence. Conclusion This unique, large, multicenter study comparing the effectiveness of iA-CPR to M-CPR will contribute to the science of the treatment of out-of-hospital cardiac arrest as well as to the design of future trials.