title: Rescuer-limited cardiopulmonary resuscitation as an alternative to 2-min switched CPR in the setting of inhospital cardiac arrest: a randomised cross-over study.
abstract: BACKGROUND
  The 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation (CPR) recommend that chest compression be rotated every 2 min to prevent rescuer fatigue. However, the quality of chest compression using 2-min switched CPR tends to decrease rapidly due to rescuer fatigue. We aimed to compare the effectiveness of use of 2-min switched CPR and rescuer-limited CPR (the person performing compressions is allowed to switch with another rescuer prior to 2 min if feeling fatigued) in the setting of inhospital cardiac arrest.
  
  
  METHODS
  Using a randomised cross-over trial design, 90 medical students were grouped into pairs to perform four cycles of 2-min switched CPR and rescuer-limited CPR (495 s per technique). During each trial, the total number of compressions performed, mean depth of compression and proportion of effective compressions performed (compression depth >5 mm) were recorded for identification of significant differences and changes in pulse rate and RR were measured to determine the extent of exhaustion.
  
  
  RESULTS
  Compared with 2-min switched CPR, the mean compression was deeper (51 vs 47 mm, p<0.001), total number of compressions greater (476 vs 397, p=0.003) and proportion of effective compressions greater (56% vs 47%, p=0.004) during rescuer-limited CPR. Subgroup analysis by 30-s unit showed more consistent compression quality during rescuer-limited CPR. No significant differences in change in pulse rate and RR were found between the two techniques.
  
  
  CONCLUSIONS
  Rescuer-limited CPR yields a greater number of effective compressions and more consistent quality of CPR than 2-min switched CPR. Rescuer-limited CPR might be a suitable alternative for treating inhospital cardiac arrest.
authors.affiliation: Department of Emergency Medicine, School of Medicine, Hallym University, Seoul, Republic of Korea.
authors.forename: Choong Hyun
authors.initials: CH
authors.lastname: Jo
authors.affiliation: Department of Emergency Medicine, School of Medicine, Hallym University, Seoul, Republic of Korea.
authors.forename: Gyu Chong
authors.initials: GC
authors.lastname: Cho
authors.affiliation: Department of Emergency Medicine, School of Medicine, Hallym University, Seoul, Republic of Korea.
authors.forename: Jung Hwan
authors.initials: JH
authors.lastname: Ahn
authors.affiliation: Department of Emergency Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Yoo Seok
authors.initials: YS
authors.lastname: Park
authors.affiliation: Department of Emergency Medical Services, Namseoul University, Cheonan-city, Choongnam, Republic of Korea.
authors.forename: Chang Hee
authors.initials: CH
authors.lastname: Lee
mesh_terms: D000328:Adult; D016887:Cardiopulmonary Resuscitation / Q000379:methods* / Q000592:standards; D018592:Cross-Over Studies; D005221:Fatigue / Q000517:prevention & control*; D005260:Female; D006323:Heart Arrest / Q000628:therapy*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008348:Manikins; D013997:Time Factors; D014481:United States; D055815:Young Adult
keywords: cardiac arrest; resuscitation