title: Effect of implementation of new resuscitation guidelines on quality of cardiopulmonary resuscitation and survival.
abstract: BACKGROUND
  During cardiopulmonary resuscitation (CPR), advanced life support (ALS) providers have been shown to deliver inadequate CPR with long intervals without chest compressions. Several changes made to the 2005 CPR Guidelines were intended to reduce unnecessary interruptions. We have evaluated if quality of CPR performed by the Oslo Emergency Medical System (EMS) improved after implementation of the modified 2005 CPR Guidelines, and if any such improvement would result in increased survival.
  
  
  METHODS
  Retrospective, observational study of all consecutive adult cardiac arrest patients treated during a 2-year period before (May 2003-April 2005), and after (January 2006-December 2007) implementation of the modified 2005 CPR Guidelines. CPR quality was assessed from continuous electronic recordings from LIFEPACK 12 defibrillators where ventilations and chest compressions were identified from transthoracic impedance changes. Ambulance run sheets, Utstein forms and hospital records were collected and outcome evaluated.
  
  
  RESULTS
  Resuscitation was attempted in 435 patients before and 481 patients after implementation of the modified 2005 CPR Guidelines. ECGs usable for CPR quality evaluation were obtained in 64% and 76% of the cases, respectively. Pre-shock pauses decreased from median (interquartile range) 17s (11, 22) to 5s (2, 17) (p=0.000), overall hands-off ratios from 0.23+/-0.13 to 0.14+/-0.09 (p=0.000), compression rates from 120+/-9 to 115+/-10 (p=0.000) and ventilation rates from 12+/-4 to 10+/-4 (p=0.000). Overall survival to hospital discharge was 11% and 13% (p=0.287), respectively.
  
  
  CONCLUSIONS
  Quality of CPR improved after implementation of the modified 2005 Guidelines with only a weak trend towards improved survival to hospital discharge.
authors.affiliation: Institute for Experimental Medical Research and Department of Anaesthesiology, Ullevål University Hospital, University of Oslo, N-0407 Oslo, Norway. t.m.olasveengen@medisin.uio.no
authors.forename: Theresa M
authors.initials: TM
authors.lastname: Olasveengen
authors.forename: Eystein
authors.initials: E
authors.lastname: Vik
authors.forename: Artem
authors.initials: A
authors.lastname: Kuzovlev
authors.forename: Kjetil
authors.initials: K
authors.lastname: Sunde
mesh_terms: D000368:Aged; D016887:Cardiopulmonary Resuscitation; D015331:Cohort Studies; D004554:Electric Countershock; D004562:Electrocardiography; D004632:Emergency Medical Services; D005260:Female; D019983:Guideline Adherence; D006323:Heart Arrest / Q000401:mortality* / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009664:Norway; D017410:Practice Guidelines as Topic; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome