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Outcomes of chest compression only CPR versus conventional CPR conducted by lay people in patients with out of hospital cardiopulmonary arrest witnessed by bystanders: nationwide population based observational study

BMJ 2011; 342 doi: (Published 27 January 2011) Cite this as: BMJ 2011;342:c7106
  1. Toshio Ogawa, assistant professor1,
  2. Manabu Akahane, lecturer1,
  3. Soichi Koike, associate professor2,
  4. Seizan Tanabe, professor3,
  5. Tatsuhiro Mizoguchi, specialist for ambulance service4,
  6. Tomoaki Imamura, professor1
  1. 1Nara Medical University School of Medicine, Department of Public Health, Health Management and Policy, 840 Shijo-cho, Kashihara, Nara 634-8521, Japan
  2. 2The University of Tokyo Hospital, Department of Planning, Information and Management, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan
  3. 3Foundation for Ambulance Service Development, Emergency Life-Saving Technique Academy of Tokyo, 4-5 Minamiosawa, Hachioji, Tokyo 192-0364, Japan
  4. 4Fire and Disaster Management Agency, Ambulance Service Planning Office, 2-1-2 Kasumigaseki, Chiyoda-ku, Tokyo 100-8927, Japan
  1. Correspondence to: T Ogawa ogawat{at}
  • Accepted 8 November 2010


Objective To compare the effectiveness of cardiopulmonary resuscitation (CPR) with chest compression only and conventional CPR on outcomes after cardiopulmonary arrest out of hospital.

Design Nationwide population based observational study.

Setting A nationwide emergency medical service system in Japan.

Population All consecutive patients with out of hospital cardiopulmonary arrest, January 2005 to December 2007 in Japan, witnessed at the moment of collapse. Lay people attempted chest compression only CPR (n=20 707) or conventional CPR (mouth to mouth ventilation and chest compression) (n=19 328), and patients were transferred to hospital by ambulance.

Main outcome measures Factors associated with better outcomes (assessed with χ2, multiple logistic regression analysis, odds ratios and their 95% confidence intervals): one month survival and neurologically favourable one month survival rates defined as category one (good cerebral performance) or two (moderate cerebral disability) of the cerebral performance categories.

Results Conventional CPR was associated with better outcomes than chest compression only CPR, for both one month survival (adjusted odds ratio 1.17, 95% confidence interval 1.06 to 1.29) and neurologically favourable one month survival (1.17, 1.01 to 1.35). Neurologically favourable one month survival decreased with increasing age and with delays of up to 10 minutes in starting CPR for both conventional and chest compression only CPR. The benefit of conventional CPR over chest compression only CPR was significantly greater in younger people in non-cardiac cases (P=0.025) and with a delay in start of CPR after the event was witnessed in non-cardiac cases (P=0.015) and all cases combined (P=0.037).

Conclusions Conventional CPR is associated with better outcomes than chest compression only CPR for selected patients with out of hospital cardiopulmonary arrest, such as those with arrests of non-cardiac origin and younger people, and people in whom there was delay in the start of CPR.


  • Contributors: TO, MA, SK, and TI conceived and designed the study. TM conducted data collection. TO analysed the data and wrote the manuscript. SK and ST wrote a part of the methods and discussion. All authors critically revised the manuscript. TO is guarantor.

  • Funding: This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

  • Competing interests: All authors have completed the Unified Competing Interest form at (available on request from the corresponding author) and declare: no support from any organisation for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work.

  • Ethical approval: This study was approved by the ethics committee of Nara Medical University (authorisation code: 260). Patient consent was not required for use of secondary data.

  • Data sharing: No additional data available.

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