Role of manual and mechanical chest compressions during resuscitation efforts throughout cardiac arrest

Abstract

The previously published randomized trials of mechanical versus manual resuscitation of patients with cardiac arrest are inconclusive, but a recent systematic review concluded: “There is no evidence that mechanical cardiopulmonary resuscitation devices improve survival; to the contrary they may worsen neurological outcome.” However, in our view, none of the randomized trials to date are definitive as the manual groups with primary cardiac arrest have not been treated optimally; that is, with minimally interrupted manual chest compressions, as advocated with cardiocerebral resuscitation. Since the mechanical chest compression devices work on different principles, it is possible that, while they may not be as effective and may even be worse in some subsets of patients, they may be preferable in others. Nevertheless, there are situations where manual chest compressions are not practical and, in these, mechanical devices may well be preferable. The Thumper® (Michigan Instruments, MI, USA) and the LUCAS™ (Jolife AB, Lund, Sweden) devices produce sternal compressions at 100 per min. By contrast, the AutoPulse® (ZOLL Circulation, CA, USA) produces chest compressions at a rate of only 80 per min. Since chest compression rate, as reviewed in this article, is important, one would guess that the devices that can produce a faster rate would be more effective. On the other hand, it could be that sternal compressions with manual or mechanical devices may be more or less effective depending on the arrested patient’s chest configuration. We speculate that in the subset of patients with barrel chests, where sternal compressions are less likely to be operative, the AutoPulse might be more effective, but less effective in thin-chested individuals, where direct cardiac compression is the major mechanism of forward blood flow in the manual, Thumper and LUCAS methods. The original LUCAS device had the potential of active decompression as well as compression. To market in the USA, holes had to be placed in the ‘suction cup’. It would be informative to know whether the original LUCAS device is more effective than the device in which the active decompression has been deactivated.