Training and educational paperCPREzy™ improves performance of external chest compressions in simulated cardiac arrest☆
Introduction
The initial goal of cardiopulmonary resuscitation (CPR) is to restore an organised, perfusing heart rhythm. External chest compressions (ECC) are a key element of CPR aiming to promote forward blood flow and therefore to maintain heart and brain viability. Even optimally performed manual ECC rarely exceeds 30% of normal vital organ blood flow1, 2 and the haemodynamic effects of ECC are dependent on the compression force,3 rate4 and duration.5 However, the overall importance and haemodynamic significance of consistent, well-performed ECC has recently been reconfirmed by laboratory investigations documenting decreased resuscitability when ECC is interrupted for rescue breathing and rhythm analysis.6, 7, 8
In contrast, the quality of ECC performed by professional healthcare providers has been called into question, and the performance by laypersons might even be worse.9, 10 The current ILCOR guidelines recommendations11 cover different facets of ECC performance, summarised in Table 1. Several devices have been developed specifically to support lay rescuers to improve adherence to these recommendations. However, none of these devices has been incorporated into clinical practice.
The CPREzy™-pad (CPREzy™) is an adjunct that has been shown to improve the performance of ECC in two studies with a small number of tested subjects and different study designs. The aim of the present study was to examine if the use of the CPREzy™ is able to improve the quality of ECC in a large population of first year medical students, if effects of training were detectable, and if the device was accepted by the users.
Section snippets
Equipment
The CPREzy™ is a re-usable, portable device designed to improve the performance of rescuers delivering ECC during CPR. It consists of a solid plastic exterior shell weighing 260 g. The external dimensions are 55 mm × 180 mm × 50 mm and a 9 V battery is necessary to power the device. A diagram on the lower part of the device indicates where it should be placed on the patient's sternum and where to apply compression force (Figure 1). After turning the device on, a series of lights in the upper part
Study population
Seventy-one percent of the tested subjects (n = 202) were female and 29% male with a mean age of 20.7 years (range 18–31 years). We excluded 28 subjects prior to the study, because of a history of medical education (17 emergency medical technicians and paramedics and 11 specialised nurses). A few students had to be eliminated from the study because of failure to attend the 2nd test due to organisational problems. The result was an unexpected reduction in group 2A compared to the other subgroups.
First evaluation
Discussion
It is accepted that good quality ECC is of particular importance in CPR. While evidence about the best method is rare, it is suspected that the guidelines’ recommendations represent a feasible compromise.
Recently published data shows weak performance of healthcare professionals especially for the rate and the depth of compressions. Wik et al. reported from out-of-hospital resuscitation a mean compression depth of 34 mm and just 28% of compressions with a depth of 38–51 mm.10 These observations
Conclusions
The CPREzy™ is a new device that is easy to use after brief instruction and is able to improve laypersons’ performance of ECC in simulated cardiac arrest. In addition, it seems to enhance the quality of classic ECC later, even if the device has only been used in resuscitation training.
With increasing evidence that ECC is becoming a more and more important part of CPR, a device helping users to meet the guidelines during ECC performance is worthy of further study.
In order to validate these
Conflict of interests
The authors declare that Health Affairs Ltd., United Kingdom, provided training devices for the investigators of the study, and they confirm, that no additional governmental nor commercial financial support that could influence the work was granted to any of the listed authors.
Acknowledgements
We thank all of the first year students of the medical faculty, University of Aachen, Germany for participating in this study and Health Affairs Ltd., United Kingdom, for loaning devices to the investigators of the study.
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2015, ResuscitationCitation Excerpt :Systems for real time feedback on CPR have proven effective to improve quality metrics,21 although no evidence has been provided on the positive effect on survival. The feedback on too slow CCs or hyperventilation can help guide rescuers towards metrics recommended by guidelines.17,22–25 In the context of advanced life support (ALS), the monitor/defibrillators may be equipped with acceleration/force sensors as well as capnography and pulse oximetry modules.
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A Spanish translated version of the summary of this article appears as Appendix in the final online version at doi:10.1016/j.resuscitation.2006.05.020.
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These authors contributed equally to the study.