A retrospective, video-based, observational study was conducted from June to September 2013 in Nantou, a rural county of central Taiwan, to evaluate the chest compression fraction in an ambulance carriage during the travel from the scene to the hospital. The chest compression fraction was calculated as the chest compression time period divided by the ambulance travelling time period; the one-handed and two-handed chest compression fractions were also calculated.

During the 4-month study period, a total of 102 videos that were recorded in an ambulance carriage were reviewed, including 97 cases of manual chest compressions. When there was only one emergency medical technician (EMT) in the carriage, the combined chest compression fraction was 50.6±20.7%; when there were two EMTs, the fraction was 58.3±16.0% and the fraction was 58.3±21.0% in a three-EMT scenario (p=0.221). Moreover, in the carriage, EMTs usually performed one-handed chest compressions.

The chest compression fraction was low for patients with out-of-hospital cardiac arrest in a moving ambulance, irrespective of the number of providers. Reasons for this observation, as well as the effectiveness of the one-handed chest compression require further evaluation.