title: Randomized crossover trial comparing physical strain on advanced life support providers during transportation using real-time automated feedback.
abstract: BACKGROUND
  Feedback devices provide verbal and visual real-time information on cardiopulmonary resuscitation (CPR) quality. Feedback devices can improve the quality of CPR during transportation. It remains unclear if feedback has an effect on the physical strain felt by providers during ongoing CPR.
  
  
  OBJECTIVE
  The objective was to assess the influence of real-time automated feedback on physical strain of rescuers during ongoing chest compressions in different means of transportation.
  
  
  METHODS
  The study was a randomized crossover trial comparing physical strain on advanced life support (ALS) providers during chest compressions using real-time automated feedback in different transport environments: 1) a moving ambulance and 2) a flying helicopter. The authors measured objective and subjective measures of physical strain and calculated the difference in the rate pressure product (RPP) after 8 minutes of external chest compressions.
  
  
  RESULTS
  There was no difference in the RPP (mean intraindividual difference = 21; 95% confidence interval [CI] = -1,438 to 1,480; p = 0.98) between using the feedback device versus no feedback. There was no significant interaction of vehicle type on the effect of feedback on the RPP. Feedback resulted in a significant mean perceived exertion reduction of a Borg scale score by 0.89 points (95% CI = 0.42 to 1.35; p < 0.001). For systolic and diastolic blood pressure, for serum lactate concentrations, and for the modified Nine Hole Peg Test (NHPT; measurement of fine motor skills), we found no statistically significant differences.
  
  
  CONCLUSIONS
  Feedback devices for CPR during transportation do not have an effect on objective components of physical strain, but decrease perceived exertion in experienced rescuers in an experimental setting.
authors.affiliation: Department of Emergency Medicine, Medical University of Vienna, Austria.
authors.forename: Christof
authors.initials: C
authors.lastname: Havel
authors.forename: Raphael
authors.initials: R
authors.lastname: van Tulder
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Schreiber
authors.forename: Moritz
authors.initials: M
authors.lastname: Haugk
authors.forename: Nina
authors.initials: N
authors.lastname: Richling
authors.forename: Helmut
authors.initials: H
authors.lastname: Trimmel
authors.forename: Reinhard
authors.initials: R
authors.lastname: Malzer
authors.forename: Harald
authors.initials: H
authors.lastname: Herkner
mesh_terms: D000328:Adult; D000552:Ambulances; D001794:Blood Pressure / Q000502:physiology; D016887:Cardiopulmonary Resuscitation; D018592:Cross-Over Studies; D015716:Electrocardiography, Ambulatory; D004634:Emergency Medical Technicians; D025461:Feedback, Physiological; D005260:Female; D006801:Humans; D007407:Interviews as Topic; D007773:Lactates / Q000097:blood; D008297:Male; D008875:Middle Aged; D005082:Physical Exertion / Q000502:physiology*; D010809:Physical Fitness
chemical_list: D007773:Lactates