Emergency medical dispatch recognition, clinical intervention and outcome of patients in traumatic cardiac arrest from major trauma : an observational study

© Author(s) (or their employer(s)) 2018. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.OBJECTIVES: The aim of this study is to describe the demographics of reported traumatic cardiac arrest (TCA) victims, prehospital resuscitation and survival to hospital rate. SETTING: Helicopter Emergency Medical Service (HEMS) in south-east England, covering a resident population of 4.5 million and a transient population of up to 8 million people. PARTICIPANTS: Patients reported on the initial 999 call to be in suspected traumatic cardiac arrest between 1 July 2016 and 31 December 2016 within the trust's geographical region were identified. The inclusion criteria were all cases of reported TCA on receipt of the initial emergency call. Patients were subsequently excluded if a medical cause of cardiac arrest was suspected. OUTCOME MEASURES: Patient records were analysed for actual presence of cardiac arrest, prehospital resuscitation procedures undertaken and for survival to hospital rates. RESULTS: 112 patients were reported to be in TCA on receipt of the 999/112 call. 51 (46%) were found not to be in TCA on arrival of emergency medical services. Of the 'not in TCA cohort', 34 (67%) received at least one advanced prehospital medical intervention (defined as emergency anaesthesia, thoracostomy, blood product transfusion or resuscitative thoracotomy). Of the 61 patients in actual TCA, 10 (16%) achieved return-of-spontaneous circulation. In 45 (88%) patients, the HEMS team escorted the patient to hospital. CONCLUSION: A significant proportion of patients reported to be in TCA on receipt of the emergency call are not in actual cardiac arrest but are critically unwell requiring advanced prehospital medical intervention. Early activation of an enhanced care team to a reported TCA call allows appropriate advanced resuscitation. Further research is warranted to determine which interventions contribute to improved TCA survival.Peer reviewedFinal Published versio

Causes of prehospital misinterpretations of ST elevation myocardial infarction

Objectives: To determine the causes of software misinterpretation of ST elevation myocardial infarction (STEMI) compared to clinically identified STEMI to identify opportunities to improve prehospital STEMI identification. Methods: We compared ECGs acquired from July 2011 through June 2012 using the LIFEPAK 15 on adult patients transported by the Los Angeles Fire Department. Cases included patients ≥18 years who received a prehospital ECG. Software interpretation of the ECG (STEMI or not) was compared with data in the regional EMS registry to classify the interpretation as true positive (TP), true negative (TN), false positive (FP), or false negative (FN). For cases where classification was not possible using registry data, 3 blinded cardiologists interpreted the ECG. Each discordance was subsequently reviewed to determine the likely cause of misclassification. The cardiologists independently reviewed a sample of these discordant ECGs and the causes of misclassification were updated in an iterative fashion. Results: Of 44,611 cases, 50% were male (median age 65; inter-quartile range 52–80). Cases were classified as 482 (1.1%) TP, 711 (1.6%) FP, 43371 (97.2%) TN, and 47 (0.11%) FN. Of the 711 classified as FP, 126 (18%) were considered appropriate for, though did not undergo, emergent coronary angiography, because the ECG showed definite (52 cases) or borderline (65 cases) ischemic ST elevation, a STEMI equivalent (5 cases) or ST-elevation due to vasospasm (4 cases). The sensitivity was 92.8% [95% CI 90.6, 94.7%] and the specificity 98.7% [95% CI 98.6, 98.8%]. The leading causes of FP were ECG artifact (20%), early repolarization (16%), probable pericarditis/myocarditis (13%), indeterminate (12%), left ventricular hypertrophy (8%), and right bundle branch block (5%). There were 18 additional reasons for FP interpretation (<4% each). The leading causes of FN were borderline ST-segment elevations less than the algorithm threshold (40%) and tall T waves reducing the ST/T ratio below threshold (15%). There were 11 additional reasons for FN interpretation occurring ≤3 times each. Conclusion: The leading causes of FP automated interpretation of STEMI were ECG artifact and non-ischemic causes of ST-segment elevation. FN were rare and were related to ST-segment elevation or ST/T ratio that did not meet the software algorithm threshold

Prehospital critical care is associated with increased survival in adult trauma patients in Scotland

Background Scotland has three prehospital critical care teams (PHCCTs) providing enhanced care support to a usually paramedic-delivered ambulance service. The effect of the PHCCTs on patient survival following trauma in Scotland is not currently known nationally. Methods National registry-based retrospective cohort study using 2011-2016 data from the Scottish Trauma Audit Group. 30-day mortality was compared between groups after multivariate analysis to account for confounding variables. Results Our data set comprised 17 157 patients, with a mean age of 54.7 years and 8206 (57.5%) of male gender. 2877 patients in the registry were excluded due to incomplete data on their level of prehospital care, leaving an eligible group of 14 280. 13 504 injured adults who received care from ambulance clinicians (paramedics or technicians) were compared with 776 whose care included input from a PHCCT. The median Injury Severity Score (ISS) across all eligible patients was 9; 3076 patients (21.5%) met the ISS>15 criterion for major trauma. Patients in the PHCCT cohort were statistically significantly (all p < 0.01) more likely to be male; be transported to a prospective Major Trauma Centre; have suffered major trauma; have suffered a severe head injury; be transported by air and be intubated prior to arrival in hospital. Following multivariate analysis, the OR for 30-day mortality for patients seen by a PHCCT was 0.56 (95% CI 0.36 to 0.86, p=0.01). Conclusion Prehospital care provided by a physician-led critical care team was associated with an increased chance of survival at 30 days when compared with care provided by ambulance clinicians

To cannulate or not to cannulate? Variation, appropriateness and potential for reduction in cannulation rates by ambulance staff

Background: Peripheral intravenous (IV) cannulation is a key intervention in the prehospital setting, but inappropriate use may cause unnecessary pain, distress or risk of infection. The aim of this study was to examine the rate and appropriateness of prehospital cannulation and the relative importance of factors associated with increased likelihood of cannulation. Design and setting: Cross-sectional survey of patients transported in Lincolnshire, East Midlands Ambulance Service. Methods: Retrospective non-identifiable data for September 2006 were extracted. Clinical conditions were classified according to whether they warranted, did not warrant or were uncertain as to the need for cannulation. Other potential indications for cannulation including IV drug administration, reduced consciousness, systolic hypotension, respiratory depression and haemorrhage were combined to determine whether cannulation was indicated. Other variables were investigated as predictors of cannulation. The method of analysis was agreed at the outset. Results: Paramedics cannulated 14.6% (1295/8866) of patients. IV drug administration, clinical indication, reduced conscious level, respiratory depression and hypotension were associated with greater likelihood of cannulation (p,0.001). Cannulation was more likely in older patients but was not associated with gender, haemorrhage or hypoglycaemia. Multivariate logistic regression showed IV drug administration as the strongest predictor of cannulation. Cannulation rates varied threefold by ambulance station (mean 13.4%, 5.8% to 19.0%). It was estimated that 202 (15.6%) of the cannulations performed could potentially have been avoided. Conclusion: Rates of cannulation were higher than previous studies with wide variations between ambulance stations. 15.6% of cannulations performed could have been avoided, thus reducing pain, distress and other potential complications such as thrombophlebitis, extravasation and infection. The generalisability of this study was limited by use of a single site, short duration and dependence on accurate retrospective data. The data demonstrating wide variations suggest that there may be scope for consideration of interventions to reduce cannulation rates

Development and pilot of clinical performance indicators for English ambulance services

Introduction: There is a compelling need to develop clinical performance indicators for ambulance services in order to move from indicators based primarily on response times and in light of the changing clinical demands on services. We report on progress on the national pilot of clinical performance indicators for English ambulance services. Method: Clinical performance indicators were developed in five clinical areas: acute myocardial infarction, cardiac arrest, stroke (including transient ischaemic attack), asthma and hypoglycaemia. These were determined on the basis of common acute conditions presenting to ambulance services and in line with a previously published framework. Indicators were piloted by ambulance services in England and results were presented in tables and graphically using funnel (statistical process control) plots. Results: Progress for developing, agreeing and piloting of indicators has been rapid, from initial agreement in May 2007 to completion of the pilot phase by the end of March 2008. The results of benchmarking of indicators are shown. The pilot has informed services in deciding the focus of their improvement programme in 2008 and 2009 and indicators have been adopted for national performance assessment of standards of prehospital care. Conclusion: The pilot will provide the basis for further development of clinical indicators, benchmarking of performance and implementation of specific evidencebased interventions to improve care in areas identified for improvement. A national performance improvement registry will enable evaluation and sharing of effective improvement methods as well as increasing stakeholder and public access to information on the quality of care provided by ambulance services

Qualitative Research of Violent Incidents Toward Young Paramedics in the Czech Republic

Introduction: Prehospital and emergency medical services (EMS) providers are usually the first to respond to an individual’s urgent health needs, sometimes in emotionally charged circumstances. Because violence toward EMS providers in the Czech Republic is often overlooked and under-reported, we do not have a complete understanding of the extent of such violence, nor do we have recommendations from EMS professional organizations on how to resolve this problem in prehospital emergency medicine.Methods: We conducted this study to explore the process of violence against EMS providers, using the Strauss/Corbin systematic approach of grounded theory to create a paradigm model. The participants in this research included personnel who had at least two years experience in the EMS systems of the city of Prague and the Central Bohemian Region, and who had been victims of violence. Our sample included 10 registered paramedics and 10 emergency medical technicians ages 23–33 (mean ± standard deviation: 27.7). The impact of communication during EMS delivery, in the context of violence from patients or their relatives, emerged as the core category and the main focus of our study. The five main groups of the paradigm model of violence against EMS personnel included causal, contextual and intervening conditions, strategies, and consequences.Results: Of the 20 study participants, 18 reported experiencing an attack during the night shift. Ten participants experienced violence on the street, and 10 inside an ambulance. The perpetrators in all 18 cases were men. The behavior of EMS personnel plays a crucial role in how violent confrontations play out: nonprofessional behavior with drunken or addict patients increases the possibility of violence in 70% of cases.Conclusion: We found that paramedics and EMTs were exposed to verbal abuse and physical violence. However, in 10 of the violent encounters reported by our 20 participants, the attack was perpetrated by otherwise-ordinary people (ie, individuals with strong family support and good jobs) who found themselves in a very stressful situation. Thanks to grounded theory we learned that for all 20 participants there was a potential opportunity to prevent the conflict

Epidemiology, prehospital care and outcomes of patients arriving by ambulance with dyspnoea: An observational study

Background: This study aimed to determine epidemiology and outcome for patients presenting to emergency departments (ED) with shortness of breath who were transported by ambulance. Methods: This was a planned sub-study of a prospective, interrupted time series cohort study conducted at three time points in 2014 and which included consecutive adult patients presenting to the ED with dyspnoea as a main symptom. For this sub-study, additional inclusion criteria were presentation to an ED in Australia or New Zealand and transport by ambulance. The primary outcomes of interest are the epidemiology and outcome of these patients. Analysis was by descriptive statistics and comparisons of proportions. Results: One thousand seven patients met inclusion criteria. Median age was 74 years (IQR 61-68) and 46.1 % were male. There was a high rate of co-morbidity and chronic medication use. The most common ED diagnoses were lower respiratory tract infection (including pneumonia, 22.7 %), cardiac failure (20.5%) and exacerbation of chronic obstructive pulmonary disease (19.7 %). ED disposition was hospital admission (including ICU) for 76.4 %, ICU admission for 5.6 % and death in ED in 0.9 %. Overall in-hospital mortality among admitted patients was 6.5 %. Discussion: Patients transported by ambulance with shortness of breath make up a significant proportion of ambulance caseload and have high comorbidity and high hospital admission rate. In this study, >60 % were accounted for by patients with heart failure, lower respiratory tract infection or COPD, but there were a wide range of diagnoses. This has implications for service planning, models of care and paramedic training. Conclusion: This study shows that patients transported to hospital by ambulance with shortness of breath are a complex and seriously ill group with a broad range of diagnoses. Understanding the characteristics of these patients, the range of diagnoses and their outcome can help inform training and planning of services

Pre-hospital management protocols and perceived difficulty in diagnosing acute heart failure

Aim To illustrate the pre-hospital management arsenals and protocols in different EMS units, and to estimate the perceived difficulty of diagnosing suspected acute heart failure (AHF) compared with other common pre-hospital conditions. Methods and results A multinational survey included 104 emergency medical service (EMS) regions from 18 countries. Diagnostic and therapeutic arsenals related to AHF management were reported for each type of EMS unit. The prevalence and contents of management protocols for common medical conditions treated pre-hospitally was collected. The perceived difficulty of diagnosing AHF and other medical conditions by emergency medical dispatchers and EMS personnel was interrogated. Ultrasound devices and point-of-care testing were available in advanced life support and helicopter EMS units in fewer than 25% of EMS regions. AHF protocols were present in 80.8% of regions. Protocols for ST-elevation myocardial infarction, chest pain, and dyspnoea were present in 95.2, 80.8, and 76.0% of EMS regions, respectively. Protocolized diagnostic actions for AHF management included 12-lead electrocardiogram (92.1% of regions), ultrasound examination (16.0%), and point-of-care testings for troponin and BNP (6.0 and 3.5%). Therapeutic actions included supplementary oxygen (93.2%), non-invasive ventilation (80.7%), intravenous furosemide, opiates, nitroglycerine (69.0, 68.6, and 57.0%), and intubation 71.5%. Diagnosing suspected AHF was considered easy to moderate by EMS personnel and moderate to difficult by emergency medical dispatchers (without significant differences between de novo and decompensated heart failure). In both settings, diagnosis of suspected AHF was considered easier than pulmonary embolism and more difficult than ST-elevation myocardial infarction, asthma, and stroke. Conclusions The prevalence of AHF protocols is rather high but the contents seem to vary. Difficulty of diagnosing suspected AHF seems to be moderate compared with other pre-hospital conditions

An observational study of patient characteristics associated with the mode of admission to acute stroke services in North East, England

Objective Effective provision of urgent stroke care relies upon admission to hospital by emergency ambulance and may involve pre-hospital redirection. The proportion and characteristics of patients who do not arrive by emergency ambulance and their impact on service efficiency is unclear. To assist in the planning of regional stroke services we examined the volume, characteristics and prognosis of patients according to the mode of presentation to local services. Study design and setting A prospective regional database of consecutive acute stroke admissions was conducted in North East, England between 01/09/10-30/09/11. Case ascertainment and transport mode were checked against hospital coding and ambulance dispatch databases. Results Twelve acute stroke units contributed data for a mean of 10.7 months. 2792/3131 (89%) patients received a diagnosis of stroke within 24 hours of admission: 2002 arrivals by emergency ambulance; 538 by private transport or non-emergency ambulance; 252 unknown mode. Emergency ambulance patients were older (76 vs 69 years), more likely to be from institutional care (10% vs 1%) and experiencing total anterior circulation symptoms (27% vs 6%). Thrombolysis treatment was commoner following emergency admission (11% vs 4%). However patients attending without emergency ambulance had lower inpatient mortality (2% vs 18%), a lower rate of institutionalisation (1% vs 6%) and less need for daily carers (7% vs 16%). 149/155 (96%) of highly dependent patients were admitted by emergency ambulance, but none received thrombolysis. Conclusion Presentations of new stroke without emergency ambulance involvement were not unusual but were associated with a better outcome due to younger age, milder neurological impairment and lower levels of pre-stroke dependency. Most patients with a high level of pre-stroke dependency arrived by emergency ambulance but did not receive thrombolysis. It is important to be aware of easily identifiable demographic groups that differ in their potential to gain from different service configurations

Door-to-balloon time in primary percutaneous coronary intervention for patients with ST-Segment Elevation Myocardial Infarction

Introduction: Over the past years Primary Percutaneous Coronary Intervention (PCI) has emerged as an effective treatment strategy for acute ST-Elevation Myocardial Infarction (STEMI).1 The survival rate with Primary PCI however is dependent on the time to treatment,2 thus, given the time dependency of survival in patient with STEMI undergoing Primary PCI, the American College of Cardiology and American Heart Association (ACC/AHA) in their management guidelines of acute myocardial infarction also endorsed by European Society of Cardiology (ESC) have established a door- to-balloon time of 90 minutes as a gold standard for Primary PCI.4 The aim of this audit is to measure and compare this key performance measurement for quality of care of patients with STEMI in the Maltese Islands. Methods: This audit was conducted at the only PCI-capable hospital in Malta – Mater Dei Hospital. All the patients coming in through the Accident and Emergency Department with an ST-elevation Myocardial Infarction or a new onset Left Bundle Branch Block (LBBB), thus eligible for a Primary PCI, were included in this audit. This was a prospective audit between January 2012 and December 2012 and using a proforma, data was collected primarily to map out the Door-to-Ballon times for Primary PCI during that period. This data was also used to pinpoint areas were time delays occur when dealing with STEMI cases. Door-to-Balloon times from pre-hospital diagnosis of STEMI using the MRX was also audited and compared to times of in-hospital STEMI diagnosis. Results: During the 12 months duration of the audit, 157 patients were recorded in the CathLab Database as having had an Emergency Primary PCI. Recorded in the audit were 135 patients of which 123 were STEMI patients eligible for a Primary PCI and 12 STEMI patients not eligible for Primary PCI and thus not included in the audit. The Mean Door-to- Balloon times of all 123 patients was found to be 101.45 minutes. Data analysis showed that the times during 'Office Hours' (8am to 5pm) were statistically significantly less than those of 'After hours' (5pm to 8am) (N=123, p<0.001) and those with a Door-to- Balloon time of more than 90 minutes, data analysis showed the number of such cases were statistically significantly less during 'Office Hours' (N=36, p=0.02). With pre-hospital ECG diagnosis of STEMI, data analysis showed that with MRX, Door-to-Ballon times are significantly less when compared to those during 'Office Hours' and 'After Hours' (N=57, p=0.003 and N=66, p<0.001 respectively). Conclusion: From the results obtained, local achievement to remain well within the standards suggested by the ACC/AHA and ESC of Primary PCI ? 90 minutes for STEMI was not reached, however several factors contributing to delays and strategies to minimize delay were pointed out in order to further improve the local practice and thus lowering mortality rates associated with STEMI.peer-reviewe