title: Does use of the CPREzy involve more work than CPR without feedback?
abstract: OBJECTIVE
  Feedback during CPR may facilitate quality in chest compressions, but has also been associated with caregiver complaints such as stiff wrists, the need for more force and increased fatigue. This concern about extra work is, when using the CPREzy with its own spring-loaded surface, particularly relevant in the face of an increased number of successive compressions. This manuscript evaluates the objective workloads for caregivers with and without the CPREzy.
  
  
  METHODS
  An air pressure driven, piston device was used to generate controlled compressions in a manikin model. The pressure was applied for chest compressions with each of the following: the cylindrical end of the piston, a wooden block as dummy for the CPREzy, and the CPREzy itself. Three manikins with subjectively different spring compliances were selected for the tests. Series of 20 compressions were performed over a wide range of pressures.
  
  
  RESULTS
  No additional force is required to achieve a given depth of compression with or without the CPREzy. However, some additional work is required, ranging from 21 to 26.5%. This work is caused by the longer compression distance associated with the need to compress two springs (e.g. the CPREzy and the chest wall) instead of one (e.g. the chest wall).
  
  
  CONCLUSIONS
  The subjective feeling of increased rescuer fatigue with the CPREzy can, at least in part, be attributed to the extra work required for compressing the spring of the CPREzy. Improved accuracy in chest compression depth is likely to be another, more significant, factor in rescuer fatigue.
authors: CPR-Lab, Department of Intensive Care, St Elisabeth Hospital, Tilburg, Netherlands.
authors: Paul F J
authors: PF
authors: van Berkom
authors: Gerrit Jan
authors: GJ
authors: Noordergraaf
authors: Gert Jan
authors: GJ
authors: Scheffer
authors: Abraham
authors: A
authors: Noordergraaf
mesh_terms: D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D004867:Equipment Design; D005246:Feedback; D006336:Heart Massage; D006801:Humans; D008348:Manikins; D010865:Pilot Projects; D011312:Pressure; D014937:Work