BACKGROUND: Our objective was to reduce hands-off time during cardiopulmonary resuscitation as increased hands-off time leads to higher mortality. METHODS: The European Resuscitation Council (ERC) 2005 and ERC 2010 guidelines were compared with an alternative sequence (ALT). Pulseless ventricular tachycardia and asystole were presented randomly to all participants in a simulation setting. A manikin (Resusci Anne; Laerdal Scandinavia A/S, Stavanger, Norway) and a defibrillator (LIFEPACK 12; Physio-Control, Inc, Redmond, WA, USA) were used. In ALT, chest compressions were only interrupted for postcharging rhythm analysis and immediate shock delivery. Comparing ALT to ERC 2005 and ERC 2010 shock delivery was done using paddles and pads, respectively. RESULTS: Sample sizes were calculated with alpha of .05 and 90% power. Hence, we needed 4 and 12 participants, respectively. In ERC 2005 vs ALT, 10 physicians were included. All had prior experience in advanced life support. Chest compressions were shorter interrupted using ALT (mean, 6.7 vs 13.0 seconds). Analyzing data for ventricular tachycardia scenarios only, hands-off time was shorter using ALT (mean, 7.1 vs 18.2 seconds). In ERC 2010 vs ALT, 12 physicians were included. Two physicians had not prior experience in advanced life support. Hands-off time was reduced using ALT (mean, 3.9 vs 5.6 seconds). Looking solely at ventricular tachycardia scenarios, hands-off time was shortened using ALT (mean, 4.5 vs 7.6 seconds). No significant reduction was observed in either of the asystole scenarios. CONCLUSION: In a simulation setting, we demonstrated that charging of the defibrillator before rhythm analysis significantly reduced hands-off time compared with the ERC 2005 and ERC 2010 guidelines.