title: Comparison of chest compression kinematics associated with over-the-head and standard cardiopulmonary resuscitation.
abstract: BACKGROUND
  Over-the-head cardiopulmonary resuscitation (CPR) is a method of chest compression, which may be easier to perform than standard CPR in a confined space.
  
  
  OBJECTIVE
  The purpose of this study was to evaluate the effects of over-the-head CPR on the kinematics and the force of delivered compressions.
  
  
  METHODS
  The subjects were 21 health care providers who were experienced in CPR. Each participant performed over-the-head CPR (O) and standard CPR (S). The compression-to-ventilation ratio was 30:2. The CPR duration was 2 minutes in each position, with a rest period of 15 minutes between each instance. The order in which positions were adopted was randomized. A manikin was equipped with a 6-axial force load cell to collect 3-dimensional compression forces at a sampling rate of 1000 Hz. An 8-camera digital motion analysis system was used to collect 3-dimensional trajectory information. Data were compared by crossover design analysis of variance (P < .05 represents statistical significance).
  
  
  RESULTS
  No significant differences in range of motion of the head, shoulder, lower trunk, hip, and knee were obtained using the 2 methods. The compression forces in O and S were 386.64 +/- 47.32 and 397.35 +/- 41.89 N, respectively (P > .05). No significant differences between the compression frequencies, depths, and percentages correct were obtained using the 2 methods.
  
  
  CONCLUSIONS
  There were no differences between the kinematics, compression forces, depths, and frequencies obtained using the O and S CPR methods as practiced by experienced providers.
authors.affiliation: Department of Emergency Medicine, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Chih-Hsien
authors.initials: CH
authors.lastname: Chi
authors.forename: Jui-Yi
authors.initials: JY
authors.lastname: Tsou
authors.forename: Fong-Chin
authors.initials: FC
authors.lastname: Su
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D008297:Male; D005082:Physical Exertion; D011187:Posture / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology*; D013647:Task Performance and Analysis; D016474:Weight-Bearing / Q000502:physiology*; D055815:Young Adult