title: One-hand chest compression and hands-off time in single-lay rescuer CPR-a manikin study.
abstract: OBJECTIVE
  To evaluate the effect of one-hand chest compression while continuously maintaining an open airway (OCOA) on rescue breath-associated hands-off time (RAHO) during single-lay rescuer cardiopulmonary resuscitation (CPR).
  
  
  METHODS
  In this study, 193 CPR/automated external defibrillator certified lay rescuers were randomly allocated into 2 groups and were tested in a standard scenario using a mannequin. In control group (group A), the participants provided standard CPR. In group B, OCOA was performed by placing the heel of the strong hand in the center of the mannequin's chest while maintaining an open airway using the other hand.
  
  
  RESULTS
  Mean RAHO was statistically significantly different between the two groups (group A: 8.38 ± 1.97 vs group B: 7.71 ± 2.43, P = .008). Only 13 (13.5%) group A and 25 (25.8%) group B providers ventilated the manikin with tidal volumes of 500 to 600 mL, while most participants caused hyperventilation. Although there were no significant differences in mean tidal volume between the groups, stomach inflation was greater in group A (< .001). Chest compressions were deeper in group A (P < .001), while chest recoil was significantly better in group B. In group B, there was a positive correlation between body mass index and compression depth (group A, P = .423; group B, P < .001).
  
  
  CONCLUSIONS
  In our study, OCOA resulted in shorter RAHO and less stomach inflation. Our results indicate that the airway should be maintained open during chest compressions, regardless of the technique. Larger studies are needed for the full clarification of OCOA.
authors.affiliation: National and Kapodistrian University of Athens, Medical School, MSc "Cardiopulmonary Resuscitation", 115 26 Athens, Greece. Electronic address: thanoschalkias@yahoo.gr.
authors.forename: Athanasios
authors.initials: A
authors.lastname: Chalkias
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Vogiatzakis
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Tampakis
authors.forename: Maria
authors.initials: M
authors.lastname: Kalafati
authors.forename: Lila
authors.initials: L
authors.lastname: Papadimitriou
authors.forename: Theodoros
authors.initials: T
authors.lastname: Xanthos
mesh_terms: D000328:Adult; D016887:Cardiopulmonary Resuscitation / Q000379:methods; D005260:Female; D006225:Hand; D006336:Heart Massage / Q000379:methods*; D006801:Humans; D008297:Male; D008348:Manikins; D013997:Time Factors