Abstracts and Programme: EUROANAESTHESIA 2011: The European Anaesthesiology Congress: Best Abstracts - Runner-up Session 2
Excessive chest compression rate is associated with insufficient compression depth in out-of-hospital cardiac arrest
Background and Goal of Study: In the latest Consensus on Science and Treatment Recommendations on Cardiopulmonary Resuscitation (ref), the relationship between compression rate and compression depth is considered to be a knowledge gap. In order to characterize this relationship, we performed an observational study in pre-hospital cardiac arrest patients.
Materials and Methods: In patients undergoing out-of-hospital cardiopulmonary resuscitation by health care professionals, chest compression rate and depth were recorded using an accelerometer (E-series monitor-defibrillator, Zoll, USA). The monitor provided real-time corrective feedback for compression rates < 80/min and for depth < 4 cm. Compression depth was analyzed for rates < 80/min, 80-120/min and >120/min. A difference in compression depth ≥5 mm was considered potentially clinically significant.
Results and Discussion: Thirty-one consecutive patients were analyzed (50375 compressions, on average 1625 per patient). Of all compressions 2% were < 80/min, 63% between 80-120/min and 35% >120/min. Mean compression depth for rates 80-120/min was 4.5 cm (SD=1) compared to 3.5 cm (SD=1) for compressions >120/min (P< 0.001; see Figure). In 20 out of 31 (64%) patients a statistically significant lower depth was observed for rates > 120/min compared to rates 80-120/min, in 10 out of 31 (32%) this difference was also clinically significant. There was no difference between the mean depth of compressions < 80/min and the mean depth of compressions 80-120/min.
Conclusion: Compression rates >120/min were associated with a lower compression depth. The observation that compression depth is lower with increased compression rates underscores the importance on feedback of rate and depth during CPR.
© 2011 European Society of Anaesthesiology
Nolan JP et al. Executive Summary 2010 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations. Resuscitation 2010; 81S: e1-e25.