A study in SJTREM suggests CPR according to the 2010 guidelines is harder to perform successfully than the previous 2005 guidelines.
Every year, first year University of Birmingham health care students (medicine, dentistry, physiotherapy) are trained in lay-rescuer CPR in accordance with the current ERC guidelines. This is followed by a standardised practical exam.
In 2010 the European Resuscitation Council (ERC) issued new guidelines, replacing the guidelines from 2005.
The 2010 guidelines emphasised a deeper compression depth. 5-6cm instead of the previously recommended 4-5cm. The 2010 guidelines also defined the compression rate interval to 100-120bpm instead of ‘100bpms per minute’
The authors wanted to study what had happened to CPR performance with the new guidelines. 561 students were in 2009-2010 assessed according to the 2005 guidelines. Their results were compared to 530 students who in 2010-2011 were trained and assessed according to the 2010 guidelines.
Overall BLS performance was worse in the 2010 group. 16,1% failed assessment as compared to 11,1% in the 2005 group. A breakdown of the criteria and where the students failed is as follows:
A significant fraction of the 2010-guidelines students delivered compressions too fast, faster than the recommended 100-120 bpm.
The authors speculate this could be a consequence of instructors and the 2010 guidelines emphasising ‘push hard and fast’ . It seems some lay-men rescuers are focusing too much on this and are overdoing it.
The consequences of a to high rate remain unclear. Animal studies show how cardiac output plateaus at a compression rate of 60–120bpm. There is nothing to gain from compressions more frequent than that.
A deleterious effect, from compression rates faster than 120bpm, could come from reducing the available time for diastolic myocardial perfusion and venous return. It increases rescuer fatigue. It’s a glitch that is potentially harmful.
Scand J Trauma Resusc Emerg Med. 2012 Aug 9;20(1):53. [Epub ahead of print] Comparison of the quality of basic life support provided by rescuers trained using the 2005 or 2010 ERC guidelines. Jones CM, Owen A, Thorne CJ, Hulme J.