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

BACKGROUND: Mechanical 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). OBJECTIVE: Evaluation of the LUCAS-2 device as a routine ambulance service treatment for OHCA. DESIGN: Pragmatic, 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. SETTING: Four 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. PARTICIPANTS: Patients 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. INTERVENTIONS: Patients received LUCAS-2 mechanical chest compression or manual chest compressions according to the first trial vehicle to arrive on scene. MAIN OUTCOME MEASURES: Survival at 30 days following cardiac arrest; survival without significant neurological impairment [Cerebral Performance Category (CPC) score of 1 or 2]. RESULTS: We 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. LIMITATIONS: There 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. CONCLUSIONS: There 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 WORK: The use of mechanical chest compression for in-hospital cardiac arrest, and in specific circumstances (e.g. transport), has not yet been evaluated. TRIAI REGISTRATION: Current Controlled Trials ISRCTN08233942. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 21, No. 11. See the NIHR Journals Library website for further project information.

Mechanical versus manual chest compression for out-of-hospital cardiac arrest (PARAMEDIC): a pragmatic, cluster randomised controlled trial.

BACKGROUND: Mechanical chest compression devices have the potential to help maintain high-quality cardiopulmonary resuscitation (CPR), but despite their increasing use, little evidence exists for their effectiveness. We aimed to study whether the introduction of LUCAS-2 mechanical CPR into front-line emergency response vehicles would improve survival from out-of-hospital cardiac arrest. METHODS: The pre-hospital randomised assessment of a mechanical compression device in cardiac arrest (PARAMEDIC) trial was a pragmatic, cluster-randomised open-label trial including adults with non-traumatic, out-of-hospital cardiac arrest from four UK Ambulance Services (West Midlands, North East England, Wales, South Central). 91 urban and semi-urban ambulance stations were selected for participation. Clusters were ambulance service vehicles, which were randomly assigned (1:2) to LUCAS-2 or manual CPR. Patients received LUCAS-2 mechanical chest compression or manual chest compressions according to the first trial vehicle to arrive on scene. The primary outcome was survival at 30 days following cardiac arrest and was analysed by intention to treat. Ambulance dispatch staff and those collecting the primary outcome were masked to treatment allocation. Masking of the ambulance staff who delivered the interventions and reported initial response to treatment was not possible. The study is registered with Current Controlled Trials, number ISRCTN08233942. FINDINGS: We enrolled 4471 eligible patients (1652 assigned to the LUCAS-2 group, 2819 assigned to the control group) between April 15, 2010 and June 10, 2013. 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 group (104 [6%] of 1652 patients) and in the manual CPR group (193 [7%] of 2819 patients; adjusted odds ratio [OR] 0·86, 95% CI 0·64-1·15). No serious adverse events were noted. Seven clinical adverse events were reported in the LUCAS-2 group (three patients with chest bruising, two with chest lacerations, and two with blood in mouth). 15 device incidents occurred during operational use. No adverse or serious adverse events were reported in the manual group. INTERPRETATION: We noted no evidence of improvement in 30 day survival with LUCAS-2 compared with manual compressions. On the basis of ours and other recent randomised trials, widespread adoption of mechanical CPR devices for routine use does not improve survival. FUNDING: National Institute for Health Research HTA - 07/37/69.

Effects of prehospital 12-lead ECG on processes of care and mortality in acute coronary syndrome: a linked cohort study from the Myocardial Ischaemia National Audit Project.

OBJECTIVE: To describe patterns of prehospital ECG (PHECG) use and determine its association with processes and outcomes of care in patients with ST-elevation myocardial infarction (STEMI) and non-STEMI. METHODS: Population-based linked cohort study of a national myocardial infarction registry. RESULTS: 288 990 patients were admitted to hospitals via emergency medical services (EMS) between 1 January 2005 and 31 December 2009. PHECG use increased overall (51% vs 64%, adjusted OR (aOR) 2.17, 95% CI 2.12 to 2.22), and in STEMI (64% vs 79%, aOR 2.34, 95% CI 2.25 to 2.44). Patients who received PHECG were younger (71 years vs 74 years, P<0.0001); and less likely to be female (33.1% vs 40.3%, OR 0.87, 95% CI 0.86 to 0.89), or to have comorbidities than those who did not. For STEMI, reperfusion was more frequent in those having PHECG (83.5% vs 74.4%, p<0.0001). PHECG was associated with more primary percutaneous coronary intervention patients achieving call-to-balloon time <90 min (27.9% vs 21.4%, aOR 1.38, 95% CI 1.24 to 1.54) and more patients who received fibrinolytic therapy achieving door-to-needle time <30 min (90.6% vs 83.7%, aOR 2.13, 95% CI 1.91 to 2.38). Patients with PHECG exhibited significantly lower 30-day mortality rates than those who did not (7.4% vs 8.2%, aOR 0.94, 95% CI 0.91 to 0.96). CONCLUSIONS: Findings from this national MI registry demonstrate a survival advantage in STEMI and non-STEMI patients when PHECG was used.

Protocol C: a nonguidelines-compliant approach to improve survival of patients with out-of-hospital cardiac arrest.

PURPOSE OF REVIEW: To describe a resuscitation protocol for out-of-hospital cardiac arrest designed for healthcare professionals that demands more from rescuers than does conventional cardiopulmonary resuscitation. It was introduced with the aim of improving survival that has remained disappointingly poor worldwide. RECENT FINDINGS: Survival to hospital discharge, that could be measured accurately in one city, improved appreciably with the use of the novel protocol. The implications are discussed in relation to the scientific background and relevant literature. SUMMARY: Uniform resuscitation protocols for lay and for professional use may not be appropriate. Only randomized trials can indicate the potential value of this challenge to conventional wisdom.

Achy breaky makey wakey heart? A randomised crossover trial of musical prompts.

OBJECTIVE: Compared with no music (NM), does listening to 'Achy breaky heart' (ABH) or 'Disco science' (DS) increase the proportion of prehospital professionals delivering chest compressions at 2010 guideline-compliant rates of 100-120 bpm and 50-60 mm depths? METHODS: A randomised crossover trial recruiting at an Australian ambulance conference. Volunteers performed three 1-min sequences of continuous chest compressions on a manikin accompanied by NM, repeated choruses of ABH and DS, prerandomised for order. RESULTS: 37 of 74 participants were men; median age 37 years; 61% were paramedics, 20% students and 19% other health professionals. 54% had taken cardiopulmonary resuscitation training within 1 year. Differences in compression rate (mode, IQR) were significant for NM (105, 99-116) versus ABH (120, 107-120) and DS (104, 103-107) versus ABH (p<0.001) but not NM versus DS (p=0.478). Differences in proportions of participants compressing at 100-120 bpm were significant for DS (61/74, 82%) versus NM (48/74, 65%, p=0.007) and DS versus ABH (47/74, 64%, p=0.007) but not NM versus ABH (p=1). Differences in compression depth were significant for NM (48 mm, 46-59 mm) versus DS (54 mm, 44-58 mm, p=0.042) but not NM versus ABH (54 mm, 43-59 mm, p=0.065) and DS versus ABH (p=0.879). Differences in proportions of subjects compressing at 50-60 mm were not significant (NM 31/74 (42%); ABH 32/74 (43%); DS 29/74 (39%); all p>0.5). CONCLUSIONS: Listening to DS significantly increased the proportion of prehospital professionals compressing at 2010 guideline-compliant rates. Regardless of intervention more than half gave compressions that were too shallow. Alternative audible feedback mechanisms may be more effective.

Utstein-style audit of Protocol C: a non-standard resuscitation protocol for healthcare professionals.

INTRODUCTION: International guidelines for basic life support and defibrillation are identical for lay people and healthcare professionals. In 2002, a small meeting hosted by the Resuscitation Council (UK) debated recent advances in resuscitation science, along with the possibility of more demanding procedures for treating out of hospital cardiac arrest (OHCA) that could take advantage of the expertise available with professional use. The resulting algorithm known as Protocol C could not be tested in a randomized trial for reasons relating to consent, but was introduced by one ambulance service as an observational study. Results from a 2-year period from one city within the service area are presented, using the Utstein style of reporting to show the recommended 'comparator' group whilst also providing epidemiological data on the frequency of cardiac arrest within the community and the outcome of all resuscitation attempts. METHODS: Manual methods were used to collect data from 2009 and 2010 for cases of cardiac arrest treated by crews from the two ambulance stations within the city of Brighton and Hove. All transported patients were tracked individually through the hospital because no official method of data linkage is available. Outcome data were obtained for survival to hospital discharge, or to 30 days for the few who remained in hospital care for that duration. RESULTS: In the epidemiological analysis, 454 patients with OHCA were treated over 2 years, of whom 151 (33%) had sustained return of spontaneous circulation (ROSC) at hospital handover and 59 (13%) survived to discharge or for 30 days. Within the 'comparator' group of 79 patients, 47 (59%) achieved sustained ROSC to hospital handover and 24 (30%) survived. CONCLUSION: The use of Protocol C has been associated with rates of sustained ROSC to hospital and of survival to discharge that have reached the range of international best practice. The improvement noted in this observational study cannot be ascribed to the new protocol alone; any wider use should await randomized trials to test the impact of this single variable. Meanwhile, wider adoption of the Utstein system to compare results for treatment of OHCA will provide a potent stimulus for emergency services to seek ways of improving outcome.

The reliability of vital signs in estimating pain severity among adult patients treated by paramedics.

BACKGROUND: The aim of this study was to examine the strength of correlation between initial pain severity score and systolic blood pressure, heart rate and respiratory rates among adults reporting pain in the prehospital setting as a means of validating the presence and severity of pain. METHODS: A retrospective cohort study was conducted including all adults with a Glasgow Coma Score >12 assessed by paramedics in a metropolitan area over a 7 day period in 2005. Pain was self-scored by patients using a 0-10 numeric rating scale (NRS). RESULTS: Of the patients transported, 1766/3357 (53%) reported pain, and an NRS score was recorded for 1286. Median age was 57 years, 51% were women, and median initial NRS was six. Mean heart rate was 85 (95% CI 84 to 86), mean systolic blood pressure was 139 mmHg (95% CI 138 to 141) and mean respiratory rate was 18 (95% CI 18 to 18). There was no significant correlation between NRS and heart rate (r=0.002, p=0.61, 95% CI -0.007 to +0.011) or blood pressure (r=-0.0007, p=0.81, 95% CI -0.007 to +0.005), although this was statistically significant for initial pain score and respiratory rate (r 0.058, p=0.001, 95% CI 0.024 to 0.093). CONCLUSION: A lack of any meaningful correlation between pain scores and changes in vital signs in this population demonstrates that these signs cannot be used to validate the severity of pain reported by adult patients.

Prehospital randomised assessment of a mechanical compression device in cardiac arrest (PaRAMeDIC) trial protocol.

BACKGROUND: Survival after out-of-hospital cardiac arrest is closely linked to the quality of CPR, but in real life, resuscitation during prehospital care and ambulance transport is often suboptimal. Mechanical chest compression devices deliver consistent chest compressions, are not prone to fatigue and could potentially overcome some of the limitations of manual chest compression. However, there is no high-quality evidence that they improve clinical outcomes, or that they are cost effective. The Prehospital Randomised Assessment of a Mechanical Compression Device In Cardiac Arrest (PARAMEDIC) trial is a pragmatic cluster randomised study of the LUCAS-2 device in adult patients with non-traumatic out-of-hospital cardiac arrest. METHODS/DESIGN: The primary objective of this trial is to evaluate the effect of chest compression using LUCAS-2 on mortality at 30 days post out-of-hospital cardiac arrest, compared with manual chest compression. Secondary objectives of the study are to evaluate the effects of LUCAS-2 on survival to 12 months, cognitive and quality of life outcomes and cost-effectiveness. METHODS: Ambulance service vehicles will be randomised to either manual compression (control) or LUCAS arms. Adult patients in out-of-hospital cardiac arrest, attended by a trial vehicle will be eligible for inclusion. Patients with traumatic cardiac arrest or who are pregnant will be excluded. The trial will recruit approximately 4000 patients from England, Wales and Scotland. A waiver of initial consent has been approved by the Research Ethics Committees. Consent will be sought from survivors for participation in the follow-up phase. CONCLUSION: The trial will assess the clinical and cost effectiveness of the LUCAS-2 mechanical chest compression device. TRIAL REGISTRATION: The trial is registered on the International Standard Randomised Controlled Trial Number Registry (ISRCTN08233942).

Does the introduction of a COPD pro-forma improve the standards of care delivered by junior doctors in the emergency department.

AIM: To determine if pro-forma based management improves standards of care delivered by junior doctors in chronic obstructive pulmonary disease (COPD) patients in the Emergency Department (ED). INTRODUCTION: National COPD audits have found large variations in ED standards of care compared to guidelines. They concluded that the publication of guidelines itself does not translate to an improvement in care. METHOD: A pro-forma based on the British Thoracic Society Guidelines on COPD, 1997, NICE Guidelines CG12, 2004 and Non Invasive Ventilation (NIV), 2002 was devised and implemented following targeted education. Data were collected pre and post pro-forma implementation and analysed. The primary end point was categorisation of respiratory failure as it was felt that this concept was fundamental in COPD management. Secondary endpoints included the administration of controlled oxygen, repeat blood gases and appropriate referral for NIV. RESULTS: There were a total of 55 patients in each group. The correct categorisation of respiratory failure improved significantly from 4% in the pre- compared to 89% (p < 0.0001) in the post-intervention group. Similarly the administration of controlled oxygen (47% compared to 92%, p < 0.0001), repeat arterial blood gases (50% compared to 83%, p = 0.0098), and appropriate referral for NIV (33% compared to 100%, p = 0.0023) showed significant improvement after the pro-forma was introduced. CONCLUSION: Pro-forma aided management significantly improves the standards of care in COPD patients in the ED.

Skill acquisition by health care workers in the Resuscitation Council (UK) 2005 Guidelines for Adult Basic Life Support.

This prospective study compared pre- and post-class performance in basic life support (BLS) on a recording manikin in a convenience sample of 34 health care workers undertaking a two-hour class provided by a hospital resuscitation department teaching the 2005 Resuscitation Council (UK) guidelines. On completion of training there were significant improvements in the proportion of subjects correctly performing a safe approach (14/34 vs. 25/33, 95%CI +11 to +55%, p=0.004), checking for response (17/34 vs. 24/32, 95%CI +1 to +46%, p=0.029), shouting for help (18/34 vs. 28/32, 95%CI +13 to +54%, p=0.002), opening the airway (6/34 vs. 26/32, 95%CI +42 to +79%, p<0.001), checking for breathing (9/34 vs. 27/32, 95%CI +35 to +74%, p<0.001), calling a cardiac arrest team (1/34 vs. 24/32, 95%CI +53 to +85%, p<0.001), and providing the correct compression to breath ratio (11/34 vs. 20/34, +3 to +48%, p=0.033). The median number of correct chest compressions increased from 3 to 41 (p<0.001) with improvements in adequate depth (median depth 36 vs. 40mm, p=0.006), although the compression rate was too fast before training and increased afterwards (median 123 vs. 147, p<0.001). Ventilation performance could not be measured accurately as the manikin was calibrated incorrectly by the manufacturers.

'Should I stay or should I go?' Deciding whether to go to hospital after a 999 call.

OBJECTIVE: In most UK ambulance services, crews attending someone who has phoned the emergency services on '999' will take the patient to hospital, unless the patient makes the decision to stay at home (or wherever they happen to be when the ambulance arrives). Safety concerns have been raised about non-conveyance decisions. We undertook a study of one UK Ambulance Service to examine ambulance crew members' views on how decision-making about non-conveyance works in practice in relation to non-urgent calls. METHODS: A total of 25 paramedics took part in three focus groups. Focus groups were transcribed and analysed thematically. RESULTS: The ambulance service's apparently straightforward guidance on decision-making about non-conveyance proved tricky in the messiness of the real world, for two reasons. The first was to do with the notion of the patient's capacity to make decisions and how this was interpreted. The second was to do with the complexity of the decision-making process, in which the patient, the crew and, in many cases, family or carers often take part in negotiation and de facto joint decision-making. CONCLUSIONS: There is a mismatch between policy and practice in relation to non-conveyance decisions. Findings should be built into research and service development in this rapidly changing field of practice in emergency and/or unscheduled care. The commonly accepted perspective on shared decision-making should be extended to include the context of '999' ambulance calls.

Optimal refresher training intervals for AED and CPR skills: a randomised controlled trial.

AIM: To determine the optimal refresher training interval for lay volunteer responders in the English National Defibrillator Programme who had previously undertaken a conventional 4-h initial class and a first refresher class at 6 months. METHODS: Subjects were randomised to receive either two additional refresher classes at intervals of 7 and 12 months or one additional refresher class after 12 months. RESULTS: Greater skill loss had occurred when the second refresher class was undertaken at 12 compared with 7 months. Skill retention however, was higher in the former group, ultimately resulting in no significant difference in final skill performance. There was no significant difference in performance between subjects attending two versus three refresher classes. On completion of refresher training all subjects were able to deliver countershocks, time to first shock decreased by 17s in both groups, and the proportion of subjects able to perform most skills increased. The execution of several important interventions remained poor, regardless of the total number of classes attended or the interval between them. These included CPR skills, defibrillation pad placement, and pre-shock safety checks. Refresher classes held more frequently and at shorter intervals increased subjects' self-assessed confidence, possibly indicating greater preparedness to use an AED in a real emergency. CONCLUSIONS: This study shows that the ability to deliver countershocks is maintained whether the second refresher class is held at seven or 12 months after the first. To limit skill deterioration between classes, however, refresher training intervals should not exceed 7 months. The quality of instruction given should be monitored carefully. Learning and teaching strategies require review to improve skill acquisition and maintenance.