title: Instructions to "push as hard as you can" improve average chest compression depth in dispatcher-assisted cardiopulmonary resuscitation.
abstract: OBJECTIVE
  Cardiopulmonary resuscitation (CPR) with adequate chest compression depth appears to improve first shock success in cardiac arrest. We evaluate the effect of simplification of chest compression instructions on compression depth in dispatcher-assisted CPR protocol.
  
  
  METHODS
  Data from two randomized, double-blinded, controlled trials with identical methodology were combined to obtain 332 records for this analysis. Subjects were randomized to either modified Medical Priority Dispatch System (MPDS) v11.2 protocol or a new simplified protocol. The main difference between the protocols was the instruction to "push as hard as you can" in the simplified protocol, compared to "push down firmly 2in. (5cm)" in MPDS. Data were recorded via a Laerdal ResusciAnne SkillReporter manikin. Primary outcome measures included: chest compression depth, proportion of compressions without error, with adequate depth and with total release.
  
  
  RESULTS
  Instructions to "push as hard as you can", compared to "push down firmly 2in. (5cm)", resulted in improved chest compression depth (36.4 mm vs. 29.7 mm, p<0.0001), and improved median proportion of chest compressions done to the correct depth (32% vs. <1%, p<0.0001). No significant difference in median proportion of compressions with total release (100% for both) and average compression rate (99.7 min(-1) vs. 97.5 min(-1), p<0.56) was found.
  
  
  CONCLUSIONS
  Modifying dispatcher-assisted CPR instructions by changing "push down firmly 2in. (5cm)" to "push as hard as you can" achieved improvement in chest compression depth at no cost to total release or average chest compression rate.
authors.affiliation: Health Informatics Program, School of Health Professions, University of Alabama at Birmingham, USA. muzna@uab.edu
authors.forename: Muzna
authors.initials: M
authors.lastname: Mirza
authors.forename: Todd B
authors.initials: TB
authors.lastname: Brown
authors.forename: Devashish
authors.initials: D
authors.lastname: Saini
authors.forename: Tracy L
authors.initials: TL
authors.lastname: Pepper
authors.forename: Hari Krishna
authors.initials: HK
authors.lastname: Nandigam
authors.forename: Niroop
authors.initials: N
authors.lastname: Kaza
authors.forename: Stacey S
authors.initials: SS
authors.lastname: Cofield
mesh_terms: D000328:Adult; D016887:Cardiopulmonary Resuscitation / Q000193:education*; D004311:Double-Blind Method; D005260:Female; D006336:Heart Massage / Q000379:methods*; D006801:Humans; D008297:Male; D008348:Manikins; D011446:Prospective Studies; D012057:Reinforcement, Verbal