Randomised controlled trials of staged teaching for basic life support - 1. Skill acquisition at bronze stage

We have investigated a method of teaching community CPR in three stages ins tead of in a single session. These have been designated bronze, silver, and gold stages. The first involves only opening of the airway and chest compr ession with back blows for choking, the second adds ventilation in a ratio of compressions to breaths of 50:5, and the third is a conversion to conven tional CPR. In a controlled randomised trial of 495 trainees we compared th e performance in tests immediately after instruction of those who had recei ved a conventional course and those who had had the simpler bronze level tu ition. The tests were based on video recordings of simulated resuscitation scenarios and the readouts from recording manikins. Differences occurred as a direct consequence of ventilation being required in one group and not th e other, some variation probably followed from unforeseen minor changes in the way that instruction was given, whilst others may have followed from th e greater simplicity in the new method of training. A careful approach was followed by slightly more trainees in the conventional group whilst appreci ably more in the bronze group remembered to shout for help (44% vs. 71%). A clear advantage was also seen for bronze level training in terms of those who opened the airway as taught (35% vs. 56%), for checking breathing (66% vs. 88%), and for mentioning the need to phone for an ambulance (21% vs. 32 %). Little difference was observed in correct or acceptable hand position b etween the conventional group who were given detailed guidance and the bron ze group who were instructed only to push on the centre of the chest. The b iggest differences related to the number of compressions given. The mean de lay to first compression was 63 s and 34 s, and the mean duration of pauses between compressions was 16 s and 9 s, respectively. Average performed rat es were similar in the two groups, but more in the conventional group compr essed too slowly whereas more in the bronze group compressed too rapidly. O bservations were made for only three cycles of compression, but extrapolati ng these to the 8 min often considered a watershed for chances of survival for victims of cardiac arrest, an average of 308 compressions would be expe cted from those using conventional CPR compared with 675 for those using br onze level CPR. The implications of this difference are discussed. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.