Prehospital randomised assessment of a mechanical compression device in out-of-hospital cardiac arrest (PARAMEDIC): a pragmatic, cluster randomised trial and economic evaluation

Abstract

BackgroundMechanical chest compression devices may help to maintain high-quality cardiopulmonary resuscitation (CPR), but little evidence exists for their effectiveness. We evaluated whether or not the introduction of Lund University Cardiopulmonary Assistance System-2 (LUCAS-2; Jolife AB, Lund, Sweden) mechanical CPR into front-line emergency response vehicles would improve survival from out-of-hospital cardiac arrest (OHCA).ObjectiveEvaluation of the LUCAS-2 device as a routine ambulance service treatment for OHCA.DesignPragmatic, cluster randomised trial including adults with non-traumatic OHCA. Ambulance dispatch staff and those collecting the primary outcome were blind to treatment allocation. Blinding of the ambulance staff who delivered the interventions and reported initial response to treatment was not possible. We also conducted a health economic evaluation and a systematic review of all trials of out-of-hospital mechanical chest compression.SettingFour UK ambulance services (West Midlands, North East England, Wales and South Central), comprising 91 urban and semiurban ambulance stations. Clusters were ambulance service vehicles, which were randomly assigned (approximately 1 : 2) to the LUCAS-2 device or manual CPR.ParticipantsPatients were included if they were in cardiac arrest in the out-of-hospital environment. Exclusions were patients with cardiac arrest as a result of trauma, with known or clinically apparent pregnancy, or aged < 18 years.InterventionsPatients received LUCAS-2 mechanical chest compression or manual chest compressions according to the first trial vehicle to arrive on scene.Main outcome measuresSurvival at 30 days following cardiac arrest; survival without significant neurological impairment [Cerebral Performance Category (CPC) score of 1 or 2].ResultsWe enrolled 4471 eligible patients (1652 assigned to the LUCAS-2 device and 2819 assigned to control) between 15 April 2010 and 10 June 2013. A total of 985 (60%) patients in the LUCAS-2 group received mechanical chest compression and 11 (< 1%) patients in the control group received LUCAS-2. In the intention-to-treat analysis, 30-day survival was similar in the LUCAS-2 (104/1652, 6.3%) and manual CPR groups [193/2819, 6.8%; adjusted odds ratio (OR) 0.86, 95% confidence interval (CI) 0.64 to 1.15]. Survival with a CPC score of 1 or 2 may have been worse in the LUCAS-2 group (adjusted OR 0.72, 95% CI 0.52 to 0.99). No serious adverse events were noted. The systematic review found no evidence of a survival advantage if mechanical chest compression was used. The health economic analysis showed that LUCAS-2 was dominated by manual chest compression.LimitationsThere was substantial non-compliance in the LUCAS-2 arm. For 272 out of 1652 patients (16.5%), mechanical chest compression was not used for reasons that would not occur in clinical practice. We addressed this issue by using complier average causal effect analyses. We attempted to measure CPR quality during the resuscitation attempts of trial participants, but were unable to do so.ConclusionsThere was no evidence of improvement in 30-day survival with LUCAS-2 compared with manual compressions. Our systematic review of recent randomised trials did not suggest that survival or survival without significant disability may be improved by the use of mechanical chest compression.Future workThe use of mechanical chest compression for in-hospital cardiac arrest, and in specific circumstances (e.g. transport), has not yet been evaluated.TriaI registrationCurrent Controlled Trials ISRCTN08233942.FundingThis project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full inHealth Technology Assessment; Vol. 21, No. 11. See the NIHR Journals Library website for further project information.

Outcome predictors of patients with out of hospital cardiac arrest and immediate coronary angiography

“…Hallstrom and college reported in a multicenter, randomized trial of patients with OHCA (1,071 patients) that the use of an automated LDB‐CPR device was associated with poor neurological outcomes and a trend toward worse survival than manual CPR. More recently Gates et al failed to demonstrate a difference regarding clinical outcomes at 30 days between mechanical CPR using LUCAS‐2 device compared to manually compression in multicenter, randomized trials. These observations correspond to our results, that the LUCAS device showed no improvement in hospital survival by patients with OHCA.…”

Automatic and manual devices for cardiopulmonary resuscitation: A review

“…There was no significant difference in 4-h survival, and almost all the survivors in both groups (99% mechanical vs 94% manual) had good neurological outcomes by 6 months (8.5% mechanical vs 7.6% manual). PARAMEDIC 33,34 was another large trial. It was a pragmatic, clusterrandomized open-label trial, enrolling adults with outof-hospital cardiac arrest as the previous trials.…”

Post-admission outcomes of participants in the PARAMEDIC trial: A cluster randomised trial of mechanical or manual chest compressions

“…7 Post-hoc additional analyses included reporting intensive care and hospital free days, mode of death and organ donation rates after death. HES admitted patient care data were used to calculate hospital length of stay and survival to hospital discharge, with supplementary discharge and death data collected in the trial.…”

“…The initial findings of the trial have been previously reported. 6,7 The study did not find an advantage to LUCAS chest compressions for the rate of return of spontaneous circulation, (LUCAS 32% vs control 31%, adjusted OR (adjusted odds ratio ((aOR)) 1.0 (95% confidence interval 0.9-1.1)), survived event (LUCAS 23% vs control 23%, aOR 1.0 (0.8-1.1)) or 30-day survival, (LUCAS 6% vs control 7%, aOR 0.9 (0.6-1.2)). However slightly more patients in the LUCAS arm had an unfavourable neurological outcome compared to those receiving manual chest compressions (5% vs 6% respectively, aOR 0.7 (0.5-1.0)).…”