Presenting the LUCAS 2.0, the latest and greatest in CPR technology! The LUCAS device “provides the same quality for all patients and over time, independent of transport conditions, rescuer fatigue, or variability in the experience level of the caregiver.” Or at least that is what the manufacturer, Physio-Control Inc, will have you believe.
High quality CPR and early defibrillation have been the cornerstones of cardiac arrest management since the AHA published their “Chain of Survival”. Reducing the time off the chest is of utmost importance in the current CPR mantra. So a machine that not only performs consistent high quality CPR, but delivers countershocks without interrupting compressions was sure to show benefit in patient oriented outcomes. What follows is a Paul Bunyan-like contest of man against machine. One in which the makers of the LUCAS device strived to prove modern technology’s superiority over good old fashion manpower. In a delightful twist on the original tale the fancy new mechanical CPR device was found to be no better than traditional CPR.
The trial published in JAMA in November 2013, randomized 2,589 subjects to either traditional CPR following the 2005 European Resuscitation Council guidelines or a mechanical compressions protocol. Patients in the mechanical CPR group received traditional compressions until the device could be deployed, at which point compressions were continued mechanically. Ninety seconds after deployment the device delivered a countershock regardless of the initial rhythm. After which the rhythm was checked every 3-minutes and, if appropriate, a shock was delivered after a 90-second delay.
Despite the obvious advantages the LUCAS device provides, no difference was found in survival at 4-hours, ICU discharge, 1-month, or 6-months. The authors claim victory in a single positive endpoint that reached significance. The number of patients with a CPC score of 1 at 1-month was 2.6% in the traditional CPR vs 4.2% in the mechanical CPR group (p-value of 0.04). This is, of course, just post-hoc dredging of innumerable secondary outcomes, and nothing more than statistical noise. To the authors’ credit, they do not revisit this positive finding.
Despite their claims that the LUCAS device would free up rescuers to do other life sustaining actions, patients in the manual CPR group were defibrillated sooner, intubated faster, transported earlier, and arrived at the hospital in a swifter fashion than those in the mechanical CPR group.
The authors conclude “CPR with this mechanical device using the presented algorithm can be delivered without major complications but did not result in improved outcomes compared with manual chest compressions.” Given that there were only 7 major adverse events in the mechanical CPR group vs 3 in the tradition CPR group this does seem to be the case. Though I would caution, with the low incidence of adverse events, this trial was not powered to truly assess safety of the mechanical delivered CPR.
“Mechanical Chest Compressions and Simultaneous Defibrillation vs Conventional Cardiopulmonary Resuscitation in Out-of-Hospital Cardiac Arrest: The LINC Randomized Trial” www.ncbi.nlm.nih.gov/pubmed/24240611