Impact of more conservative European Society of Cardiology guidelines on the management of patients with acute chest pain.

OBJECTIVE: Early diagnosis or rule-out of acute coronary syndrome (ACS) is a key competence of emergency medicine. Changes in the NSTE-ACS guidelines of the European Society of Cardiology (ESC) in 2015 and 2020 both warranted a henceforth more conservative approach regarding high-sensitivity troponin t (hsTnt) testing. We aimed to assess the impact of more conservative guidelines on the frequency of early rule-out and prolonged observation with repeated hsTnt testing at a high-volume tertiary care emergency department. PATIENTS AND METHODS: We conducted a pre- and post-changeover analysis 3 months before and 3 months after transition from less (hsTnt cut-off 30 ng/L, 3-hour rule-out) to more conservative (hsTnt cut-off 14 ng/L, 1-hour rule-out) guidelines in 2015, comparing proportions of patients requiring repeated testing. RESULTS: We included 5442 cases of symptoms suspicious of acute cardiac origin (3451 before, 1991 after, 2370 (44%) female, age 55 (SD 19) years). The proportion of patients fulfilling early-rule out criteria decreased from 68% (2348 patients) before to 60% (1195 patients) with the 2015 guidelines (P < .01). Those requiring repeated testing significantly (P < .01) increased from 22% (743 patients) to 25% (494 patients). Positive results in repeated testing significantly (P = .02) decreased from 43% (320 patients) to 37% (181 patients). Invasive diagnostics were performed in 91 patients (2.6%) before and in 75 patients (3.8%) after (P = .02) the guideline revision. CONCLUSION: The implementation of the more conservative 2015 ESC guidelines led to a minor rise in prolonged observations because of an increase in negative repeated testing and to an increase in invasive procedures.

Laryngeal Tube Practice in a Metropolitan Ambulance Service: A Five-year Retrospective Observational Study (2009-2013).

Background: The endotracheal tube (ETT) is considered the gold standard in emergency airway management, although supraglottic airway devices, especially the laryngeal tube (LT), have recently gained in importance. Although regarded as an emergency device in case of failure of endotracheal intubation in most systems, we investigated the dynamics of the use of the LT in a metropolitan ambulance service without any regulations on the choice of airway device. Methods: A retrospective, observational study on all patients from the Municipal Ambulance Service, Vienna in need of advanced airway management over a 5-year period. Differences between years were compared; influencing factors for the use of the LT were analyzed using multivariable logistic regression. Results: In total 5,175 patients (mean age 62 ± 20 years, 36.6% female) underwent advanced airway management. Of these, 15.6% received the LT. LT use increased from 20 out of 1,001 (2.0%) in 2009 to 292 of 1,085 (26.9%) in 2013 (p < 0.001). The increase between each consecutive year was also significant. Paramedics more frequently inserted the LT than physicians (RR 1.80 (95%CI 1.48-2.16); p < 0.001). Female patients received a LT less frequently (RR 0.84 (95%CI 0.72-0.97), p = 0.013). There was no difference regarding airway device due to underlying causes requiring airway management and no relationship to the NACA-score. Conclusion: In a European EMS system of physician and paramedic response, the proportion of airway managed by LT over ETT rose considerably over five years. Although the ET is still the gold standard, the LT is gaining in importance for EMS physicians and paramedics.

Risk stratification in acute coronary syndrome: Evaluation of the GRACE and CRUSADE scores in the setting of a tertiary care centre.

OBJECTIVE: Risk assessment plays a decisive role in the management of acute coronary syndrome (ACS). The GRACE and the CRUSADE scores are among the most frequently used risk assessment tools. We aimed to compare the performance of the GRACE and CRUSADE risk scores to predict in-hospital mortality and major bleeding in a contemporary ACS population at a high-volume academic hospital. METHODS: All patients treated for ACS from January 1, 2006 to December 31, 2015 at a tertiary care centre were prospectively enrolled. We calculated GRACE and CRUSADE risk scores. We compared the discrimination capacity of both scores for in-hospital mortality and major bleeding. RESULTS: In total 4087 patients (1151 [28.2%] female; age 62 ± 14 years) were included. Among these 2218 (54.3%) were diagnosed with ST-elevation myocardial infarction, 113 (2.8%) died in hospital and major bleeding occurred in 65 (1.6%). Discrimination capacity for in-hospital mortality of the GRACE score was superior to the CRUSADE score (receiver operator characteristic area under the curve (AUC) 0.91 (95% CI 0.89-0.93) vs 0.83 (95% CI 0.80-0.86); P < .01). Performance for major bleeding differed but was poor for both scores (AUC 0.71 [0.65-0.76] for GRACE vs 0.61 [0.55-0.68] for CRUSADE; P < .01). CONCLUSION: The GRACE score appears to be superior over CRUSADE to predict in-hospital mortality. Major bleeding is rare in the era of primary PCI and performance of both scores for this outcome was poor.

Gender and age-specific aspects of awareness and knowledge in basic life support.

BACKGROUND: The 'chain of survival'-including early call for help, early cardiopulmonary resuscitation (CPR) and early defibrillation-represents the most beneficial approach for favourable patient outcome after out-of-hospital cardiac arrest (OHCA). Despite increasing numbers of publicly accessible automated external defibrillators (AED) and interventions to increase public awareness for basic life support (BLS), the number of their use in real-life emergency situations remains low. METHODS: In this prospective population-based cross-sectional study, a total of 501 registered inhabitants of Vienna (Austria) were randomly approached via telephone calls between 08/2014 and 09/2014 and invited to answer a standardized questionnaire in order to identify public knowledge and awareness of BLS and AED-use. RESULTS: We found that more than 52 percent of participants would presume OHCA correctly and would properly initiate BLS attempts. Of alarming importance, only 33 percent reported that they would be willing to perform CPR and 50 percent would use an AED device. There was a significantly lower willingness to initiate BLS attempts (male: 40% vs. female: 25%; OR: 2.03 [95%CI: 1.39-2.98]; p<0.001) and to use an AED device (male: 58% vs. female: 44%; OR: 1.76 [95%CI: 1.26-2.53]; p = 0.002) in questioned female individuals compared to their male counterparts. Interestingly, we observed a strongly decreasing level of knowledge and willingness for BLS attempts (-14%; OR: 0.72 [95%CI: 0.57-0.92]; p = 0.027) and AED-use (-19%; OR: 0.68 [95%CI: 0.54-0.85]; p = 0.001) with increasing age. CONCLUSION: We found an overall poor knowledge and awareness concerning BLS and the use of AEDs among the Viennese population. Both female and elderly participants reported the lowest willingness to perform BLS and use an AED in case of OHCA. Specially tailored programs to increase awareness and willingness among both the female and elderly community need to be considered for future educational interventions.

Non-occlusive mesenteric ischaemia in out of hospital cardiac arrest survivors.

BACKGROUND AND AIM OF THE STUDY: Non-occlusive mesenteric ischaemia (NOMI) is characterised by hypoperfusion of the intestines without evidence of mechanical obstruction, potentially leading to extensive ischaemia and necrosis. Low cardiac output appears to be a major risk factor. Cardiopulmonary resuscitation aims at restoring blood flow after cardiac arrest. However, post restoration of spontaneous circulation, myocardial stunning limits immediate recovery of sufficient cardiac function. Since after successful cardiopulmonary resuscitation patients are often ventilated and sedated, NOMI might be underdiagnosed and potentially life-saving treatment delayed. MATERIAL AND METHODS: A prospectively maintained multi-purpose cohort of out of hospital cardiac arrest survivors, who had successful restoration of spontaneous circulation, was used for this retrospective database analysis. Patients' charts were screened for clinical, radiological or pathological evidence of NOMI and clinical data were collected. RESULTS: Between 2000 and 2014, 1780 patients who were successfully resuscitated after out of hospital cardiac arrest were screened for NOMI. Twelve patients (0.68 %) suffered from NOMI and six of those died (50 %). Patients suffering from NOMI tended to have a longer duration until restoration of spontaneous circulation (27 vs. 20 min, p=0.128) and had significantly higher lactate (14 mmol/l vs. 8 mmol/l, p=0.002) and base deficit levels at admission (-17 vs. -10, p=0.012). Median leukocyte counts in NOMI patients peaked at the day of diagnosis. CONCLUSION: NOMI is a rare but life-threatening and potentially curable complication following successful cardiopulmonary resuscitation. Lactate and base deficit at admission could help to identify patients at risk for developing NOMI who might benefit from increased clinical attention.

The impact of airway strategy on the patient outcome after out-of-hospital cardiac arrest: A propensity score matched analysis.

BACKGROUND: While guidelines mentioned supraglottic airway management in the case of out-of- hospital cardiac arrest, robust data of their impact on the patient outcome remain scare and results are inconclusive. METHODS: To assess the impact of the airway strategy on the patient outcome we prospectively enrolled 2224 individuals suffering cardiac arrest who were treated by the Viennese municipal emergency medical service. To control for potential confounders, propensity score matching was performed. Patients were matched in four groups with a 1:1:1:1 ratio ( n=210/group) according to bag-mask-valve, laryngeal tube, endotracheal intubation and secondary endotracheal intubation after primary laryngeal tube ventilation. RESULTS: The laryngeal tube subgroup showed the lowest 30-day survival rate among all tested devices ( p<0.001). However, in the case of endotracheal intubation after primary laryngeal tube ventilation, survival rates were comparable to the primary endotracheal tube subgroup. The use of a laryngeal tube was independently and directly associated with mortality with an adjusted odds ratio of 1.97 (confidence interval: 1.14-3.39; p=0.015). Additionally, patients receiving laryngeal tube ventilation showed the lowest rate of good neurological performance (6.7%; p<0.001) among subgroups. However, if patients received endotracheal intubation after initial laryngeal tube ventilation, the outcome proved to be significantly better (9.5%; p<0.001). CONCLUSION: We found that the use of a laryngeal tube for airway management in cardiac arrest was significantly associated with poor 30-day survival rates and unfavourable neurological outcome. A primary endotracheal airway management needs to be considered at the scene, or an earliest possible secondary endotracheal intubation during both pre-hospital and in-hospital post-return of spontaneous circulation critical care seems crucial and most beneficial for the patient outcome.

[Dispatchers' impressions and actual quality of cardiopulmonary resuscitation during telephone-assisted bystander cardiopulmonary resuscitation: a pooled analysis of 94 simulated, manikin-based scenarios]. / Impresiones de los teleoperadores sobre la calidad real de la reanimación cardiopulmonar asistida por teléfono: análisis conjunto de 94 escenarios simulados con maniquíes.

OBJECTIVES: The quality of telephone-assisted cardiopulmonary resuscitation (CPR) needs improvement. This study investigates whether a dispatchers' perception is an adequate measure of the actual quality of CPR provided by laypersons. MATERIAL AND METHODS: Individual participant data from 3 randomized simulation trials, with identical methodology but different interventions, were combined for this analysis. Professional dispatchers gave telephone assistance to laypersons, who each provided 10 minutes of CPR on a manikin. Dispatchers were requested to classify the quality of providers' CPR as adequate or inadequate. Based on actual readings from manikins we classified providers' performance as adequate at 5-6 cm for depth and 100-120 compressions per minute (cpm) for rate. We calculated metrics of dispatcher accuracy. RESULTS: Six dispatchers rated the performance of 94 laypersons (38 women [42%]) with a mean (SD) age of 37 (14) years. In 905 analyzed minutes of telephone-assisted CPR, the mean compression depth and rate was 41 (13) mm and 98 (24) cpm, respectively. Analysis of dispatchers' diagnostic test accuracy for adequate compression depth yielded a sensitivity of 65% (95 CI 36%-95%) and specificity of 42% (95% CI, 32%-53%). Analysis of their assessment of adequate compression rate yielded a sensitivity of 75% (95% CI, 64%-86%) and specificity of 42% (95% CI, 32%-52%). Although dispatchers always underestimated the actual values of CPR parameters, the female dispatchers evaluations were less inaccurate than the evaluations of make dispatchers; the dispatchers overall (males and females together) underestimated the adequacy of female laypersons' CPR performance to a greater degree than female dispatchers did. CONCLUSION: The ability of dispatchers to estimate the quality of telephone-assisted CPR is limited. Dispatchers estimates of CPR adequacy needs to be studied further in order to find ways that telephone-assisted CPR might be improved.

OBJETIVO: Investigar si la percepción de los teleoperadores es una medida adecuada de la calidad real de la reanimación cardiopulmonar (RCP) proporcionada por los intervinientes. METODO: Se combinaron los datos individuales en tres ensayos aleatorios de simulación, con idéntica metodología pero con diferentes intervenciones y en los que teleoperadores profesionales dieron asistencia telefónica a los intervinientes. Cada interviniente realizó 10 minutos de RCP en un maniquí. Se pidió a los teleoperadores que clasificaran la calidad de la RCP de los intervinientes como adecuada o inadecuada. Mediante las lecturas reales de los maniquíes, se clasificó la RCP de los intervinientes como adecuada si cumplían valores entre 5 y 6 cm para la profundidad y 100- 120 compresiones por minuto (cpm) para la frecuencia. Se calculó la precisión de los teleoperadores. RESULTADOS: El rendimiento de la RCP de 94 intervinientes (edad 37 (DE 14) años, 38 (43%) mujeres) fue calificado por 6 teleoperadores. En 905 minutos de RCP telefónica analizados, la profundidad y la tasa media de compresión fueron 41 (DE 13) mm y 98 (DE 24) cpm, respectivamente. La precisión de los teleoperadores para valorar una profundidad de compresión adecuada tuvo una sensibilidad de un 65% (IC 95% 36-95) y una especificidad de un 42% (IC 95% 32-53). La sensibilidad para un ritmo de compresión adecuado fue de un 75% (95% IC 64-86) y la especificidad fue de un 42% (IC del 95%: 32-52). Aunque la estimación por parte de los teleoperadores de los parámetros de RCP siempre fue inferior a la realidad, esta subestimación era menor por parte de las teleoperadoras, en tanto que la subestimación era mayor cuando los teleoperadores (hombres y mujeres) valoraban intervenientes mujeres. CONCLUSIONES: La capacidad de los teleoperadores para estimar la calidad de la RCP asistida telefónicamente es limitada.

Age-specific prognostication after out-of-hospital cardiac arrest - The ethical dilemma between 'life-sustaining treatment' and 'the right to die' in the elderly.

BACKGROUND: While prognostic values on survival after out-of-hospital cardiac arrest have been well investigated, less attention has been paid to their age-specific relevance. Therefore, we aimed to identify suitable age-specific early prognostication in elderly patients suffering out-of-hospital cardiac arrest in order to reduce the burden of unnecessary treatment and harm. METHODS: In a prospective population-based observational trial on individuals suffering out-of-hospital cardiac arrest, a total of 2223 patients receiving resuscitation attempts by the local emergency medical service in Vienna, Austria, were enrolled. Patients were stratified according to age as follows: young and middle-aged individuals (<65 years), young old individuals (65-74 years), old individuals (75-84 years) and very old individuals (>85 years). RESULTS: There was an increasing rate of 30-day mortality (+21.8%, p < 0.001) and unfavourable neurological outcome (+18.8%, p < 0.001) with increasing age among age groups. Established predictive variables lost their prognostic potential with increasing age, even after adjusting for potential confounders. Independently, an initially shockable electrocardiogram proved to be directly associated with survival, with an adjusted hazard ratio (HR) of 2.04 (95% confidence interval (CI) 1.89-2.38, p = 0.003) for >85-year-olds. Frailty was directly associated with mortality (HR 1.22, 95% CI 1.01-1.51, p = 0.049), showing a 30-day survival of 5.6% and a favourable neurological outcome of 1.1% among elderly individuals. CONCLUSION: An initially shockable electrocardiogram proved to be a suitable tool for risk assessment and decision making in order to predict a successful outcome in elderly victims of out-of-hospital cardiac arrest. However, the outcomes of elderly patients seemed to be exceptionally poor in frail individuals and need to be considered in order to reduce unnecessary treatment decisions.

Safety and feasibility of the RhinoChill immediate transnasal evaporative cooling device during out-of-hospital cardiopulmonary resuscitation: A single-center, observational study.

We investigated feasibility and safety of the RhinoChill (RC) transnasal cooling system initiated before achieving a protected airway during cardiopulmonary resuscitation (CPR) in a prehospital setting.In out-of-hospital cardiac arrest (OHCA), transnasal evaporative cooling was initiated during CPR, before a protected airway was established and continued until either the patient was declared dead, standard institutional systemic cooling methods were implemented or cooling supply was empty. Patients were monitored throughout the hypothermia period until either death or hospital discharge. Clinical assessments and relevant adverse events (AEs) were documented over this period of time.In total 21 patients were included. Four were excluded due to user errors or meeting exclusion criteria. Finally, 17 patients (f = 6; mean age 65.5 years, CI95%: 57.7-73.4) were analyzed. Device-related AEs, like epistaxis or nose whitening, occurred in 2 patients. They were mild and had no consequence on the patient's outcome. According to the field reports of the emergency medical services (EMS) personnel, no severe technical problems occurred by using the RC device that led to a delay or the impairment of quality of the CPR.Early application of the RC device, during OHCA is feasible, safe, easy to handle, and does not delay or hinder CPR, or establishment of a secure intubation. For efficacy and further safety data additional studies will be needed.

Editor's Choice-Progress in the chain of survival and its impact on outcomes of patients admitted to a specialized high-volume cardiac arrest center during the past two decades.

AIM: Cardiac arrest (CA) is still associated with high mortality and morbidity. Data on the changes in management and outcomes over a long period of time are limited. Using data from a single emergency department (ED), we assessed changes over two decades. METHODS: In this single-center observational study, we prospectively included 4133 patients receiving cardiopulmonary resuscitation and being admitted to the ED of a tertiary care hospital between January 1992 and December 2012. RESULTS: There was a significant improvement in both 6-month survival rates (+10.8%; p < 0.001) and favorable neurological outcome (+4.7%; p < 0.001). While the number of witnessed CA cases decreased (-4.7%; p < 0.001) the proportion of patients receiving bystander basic life support increased (+8.3%; p < 0.001). The proportion of patients with initially shockable ECG rhythms remained unchanged, but cardiovascular causes of CA decreased (-9.6%; p < 0.001). Interestingly, the time from CA until ED admission increased (+0.1 hours; p = 0.024). The use of percutaneous coronary intervention and therapeutic hypothermia were significantly associated with survival. CONCLUSIONS: Outcomes of patients with CA treated at a specialized ED have improved significantly within the last 20 years. Improvements in every link in the chain of survival were noted.

Mechanical chest compression does not seem to improve outcome after out-of hospital cardiac arrest. A single center observational trial.

AIM: Recently three large post product placement studies, comparing mechanical chest compression (cc) devices to those who received manual cc, found equivalent outcome results for both groups. Thus the question arises whether those results could be replicated using the devices on a daily routine. METHODS: We prospectively enrolled 948 patients over a 12 months period. Chi-Square test and Mann-Whitney-U test were used to assess differences between "manual" and "mechanical" cc subgroups. Uni- and multivariate Cox regression hazard analysis were used to assess the influence of cc type on survival. RESULTS: A mechanical cc device was used in 30.1% (n=283) cases. Patients who received mechanical cc had a significantly worse neurological outcome - measured in cerebral performance category (CPC) - than the manual cc group (56.8% vs. 78.6%, p=0.009). Patients receiving mechanical cc were significantly younger, more were male and were more likely to have bystander CPR and an initially shock-able ECG rhythm. There was no difference in the quality of CPR that might explain the worse outcome in mechanical cc patients. CONCLUSION: Even with high quality CPR in both, manual and mechanical cc groups, outcome in patients who received mechanical cc was significantly worse. The anticipated benefits of a higher compression ratio and a steadier compression depth of a mechanical cc device remain uncertain. In this study selection for mechanical cc was not standardized, and was non-random. This merits further investigation. Further research on how mechanical cc is chosen and used should be considered. CLINICAL TRIAL REGISTRATION: https://ekmeduniwien.at/core/catalog/2013/ (EK-Nr:1221/2013).

The incidence of "load&go" out-of-hospital cardiac arrest candidates for emergency department utilization of emergency extracorporeal life support: A one-year review.

BACKGROUND: The outcome of patients after out-of-hospital cardiac arrest (OHCA) is poor and gets worse after prolonged resuscitation. Recently introduced attempts like an early installed emergency extracorporeal life support (E-ECLS) in patients with persisting cardiac arrest at the emergency department (ED) are tried. The "Vienna Cardiac Arrest Registry" (VICAR) was introduced August 2013 to collect Utstein-style data. The aim of this observational study was to identify the incidence of patients which fulfil "load&go"-criteria for E-ECLS at the ED. METHODS: VICAR was retrospectively analyzed for following criteria: age <75 years; witnessed OHCA; basic life support; ventricular fibrillation/ventricular tachycardia; no return-of-spontaneous-circulation (ROSC) within 15 min of advanced-life-support, which were supposed as potential optimal criteria for "load&go" plus successful E-ECLS treatment at the ED. The observation period was from August 1, 2013 to July 31, 2014. RESULTS: Over 948 OHCA patients registered during the study period; data were exploitable for 864 patients. Of all patients, "load&go"-criteria were fulfilled by 55 (6%). However, 96 (11%) were transported with on-going CPR to the ED. Of these 96 patients, only 16 (17%) met the "load&go"-criteria. Similarly, among the 96 patients, 12 adults were treated with E-ECLS at the ED, with only 5 meeting the criteria. Among these 12 patients, favourable neurological outcome (CPC 1/2) was obtained in 1 patient without criteria. CONCLUSION: Further promotion of these criteria within the ambulance crews is needed. May be these criteria could serve as a decision support for emergency physicians/paramedics, which patients to transport with on-going CPR to the ED for E-ECLS.

The capability of professional- and lay-rescuers to estimate the chest compression-depth target: a short, randomized experiment.

BACKGROUND: In CPR, sufficient compression depth is essential. The American Heart Association ("at least 5cm", AHA-R) and the European Resuscitation Council ("at least 5cm, but not to exceed 6cm", ERC-R) recommendations differ, and both are hardly achieved. This study aims to investigate the effects of differing target depth instructions on compression depth performances of professional and lay-rescuers. METHODS: 110 professional-rescuers and 110 lay-rescuers were randomized (1:1, 4 groups) to estimate the AHA-R or ERC-R on a paper sheet (given horizontal axis) using a pencil and to perform chest compressions according to AHA-R or ERC-R on a manikin. Distance estimation and compression depth were the outcome variables. RESULTS: Professional-rescuers estimated the distance according to AHA-R in 19/55 (34.5%) and to ERC-R in 20/55 (36.4%) cases (p=0.84). Professional-rescuers achieved correct compression depth according to AHA-R in 39/55 (70.9%) and to ERC-R in 36/55 (65.4%) cases (p=0.97). Lay-rescuers estimated the distance correctly according to AHA-R in 18/55 (32.7%) and to ERC-R in 20/55 (36.4%) cases (p=0.59). Lay-rescuers yielded correct compression depth according to AHA-R in 39/55 (70.9%) and to ERC-R in 26/55 (47.3%) cases (p=0.02). CONCLUSION: Professional and lay-rescuers have severe difficulties in correctly estimating distance on a sheet of paper. Professional-rescuers are able to yield AHA-R and ERC-R targets likewise. In lay-rescuers AHA-R was associated with significantly higher success rates. The inability to estimate distance could explain the failure to appropriately perform chest compressions. For teaching lay-rescuers, the AHA-R with no upper limit of compression depth might be preferable.

[Effects of a voice metronome on compression rate and depth in telephone assisted, bystander cardiopulmonary resuscitation: an investigator-blinded, 3-armed, randomized, simulation trial]. / Efectos de un metrónomo (de voz) en la frecuencia y profundidad de compresiones de una reanimación cardiopulmonar por un primer interviniente asistida telefónicamente. Un ensayo de simulación, aleatorizado y ciego.

OBJECTIVES: We investigated the effect on compression rate and depth of a conventional metronome and a voice metronome in simulated telephone-assisted, protocol-driven bystander Cardiopulmonary resucitation (CPR) compared to standard instruction. MATERIAL AND METHODS: Thirty-six lay volunteers performed 10 minutes of compression-only CPR in a prospective, investigator-blinded, 3-arm study on a manikin. Participants were randomized either to standard instruction ("push down firmly, 5 cm"), a regular metronome pacing 110 beats per minute (bpm), or a voice metronome continuously prompting "deep-deepdeep- deeper" at 110 bpm. The primary outcome was deviation from the ideal chest compression target range (50 mm compression depth x 100 compressions per minute x 10 minutes = 50 m). Secondary outcomes were CPR quality measures (compression and leaning depth, rate, no-flow times) and participants' related physiological response (heart rate, blood pressure and nine hole peg test and borg scales score). We used a linear regression model to calculate effects. RESULTS: The mean (SD) deviation from the ideal target range (50 m) was -11 (9) m in the standard group, -20 (11) m in the conventional metronome group (adjusted difference [95%, CI], 9.0 [1.2-17.5 m], P=.03), and -18 (9) m in the voice metronome group (adjusted difference, 7.2 [-0.9-15.3] m, P=.08). Secondary outcomes (CPR quality measures and physiological response of participants to CPR performance) showed no significant differences. CONCLUSION: Compared to standard instruction, the conventional metronome showed a significant negative effect on the chest compression target range. The voice metronome showed a non-significant negative effect and therefore cannot be recommended for regular use in telephone-assisted CPR.

OBJETIVO: Se investigó el efecto sobre la tasa y profundidad de compresión utilizando un metrónomo regular, un metrónomo de voz, en comparación con instrucciones estándar, siguiendo el protocolo de reanimación cardiopulmonar (RCP) por interviniente con asistencia telefónica. METODO: Treinta y seis individuos legos realizaron 10 minutos de compresiones de RCP sobre un maniquí en un estudio prospectivo, ciego. Los participantes fueron asignados al azar, ya sea en base a la instrucción estándar (empuje hacia abajo con firmeza 5 cm); a un metrónomo normal a un ritmo de 110 pulsaciones por minuto (ppm) o un metrónomo de voz incitando continuamente "profundo-profundo-profundo-más profunda" a 110 ppm. El objetivo primario fue evaluar la desviación del rango objetivo ideal de compresión torácica (50 mm de profundidad de compresión x 100 compresiones por minuto x 10 minutos = 50 m). Los objetivos secundarios fueron las mediciones de RCP de calidad (profundidad y tasa de compresiones, comprensiones que no generan flujo) y la respuesta fisiológica de los participantes (frecuencia cardiaca, presión arterial, Nine Hole Peg Test y Escala de Borg). Se utilizó un modelo de regresión lineal para calcular los resultados. RESULTADOS: En relación al objetivo primario, la desviación del rango objetivo ideal (50 metros) fue ­11 (9) m en el grupo estándar versus ­20 (11) m en el grupo de metrónomo regular (diferencia ajustada 9,0 (1,2-17,5) m, p = 0,03), y ­18 (9) m en el grupo de metrónomo de voz [diferencia ajustada de 7,2 (­0,9 a 15,3) m, p = 0,08]. Los objetivos secundarios con respecto a las medidas de calidad de RCP y la respuesta fisiológica de los participantes durante la realización de RCP no mostraron diferencias significativas. CONCLUSIONES: El metrónomo normal y el metrónomo de voz mostraron un efecto negativo (significativo y no significativo respectivamente) en el rango objetivo de compresión torácica en comparación con la instrucción estándar y por lo tanto no puede ser recomendado su uso regular en la RCP asistida telefónicamente.

Neurologic causes of cardiac arrest and outcomes.

BACKGROUND: Sudden cardiac arrest as a complication of neurologic disorders is rare, occasionally acute neurologic events present with cardiac arrest as initial manifestation. OBJECTIVE: Our aim was to describe neurologic disorders as a cause of cardiac arrest in order to enable better recognition. METHODS: We retrospectively analyzed prospectively collected resuscitation data of all patients treated between 1991 and 2011 at the emergency department after cardiac arrest caused by a neurologic event, including diagnosis, therapy, and outcomes. RESULTS: Over 20 years, 154 patients suffered cardiac arrest as a result of a neurologic event. Out-of-hospital cardiac arrest occurred in 126 (82%) patients, 78 (51%) were male, median age was 51 years (interquartile range 17 to 89 years). As initial electrocardiogram rhythm, pulseless electrical activity was found in 77 (50%) cases, asystole in 61 (40%), and ventricular fibrillation in 16 (10%) cases. The most common cause was subarachnoid hemorrhage in 74 (48%) patients, 33 (21%) patients had intracerebral hemorrhage, 23 (15%) had epileptic seizure, 11 (7%) had ischemic stroke, and 13 (8%) had other neurologic diseases. Return of spontaneous circulation was achieved in 139 (90%) patients. Of these, 22 (14%) were alive at follow-up after 6 months, 14 (9%) with favorable neurologic outcome, 8 of these with epileptic seizure, and most of them with history of epilepsy. CONCLUSIONS: Subarachnoidal hemorrhage is the leading neurologic cause of cardiac arrest. Most of the patients with cardiac arrest caused by neurologic disorder have a very poor prognosis.

"Push as hard as you can" instruction for telephone cardiopulmonary resuscitation: a randomized simulation study.

BACKGROUND: The medical priority dispatch system (MPDS®) assists lay rescuers in protocol-driven telephone-assisted cardiopulmonary resuscitation (CPR). OBJECTIVE: Our aim was to clarify which CPR instruction leads to sufficient compression depth. METHODS: This was an investigator-blinded, randomized, parallel group, simulation study to investigate 10 min of chest compressions after the instruction "push down firmly 5 cm" vs. "push as hard as you can." Primary outcome was defined as compression depth. Secondary outcomes were participants exertion measured by Borg scale, provider's systolic and diastolic blood pressure, and quality values measured by the skill-reporting program of the Resusci(®) Anne Simulator manikin. For the analysis of the primary outcome, we used a linear random intercept model to allow for the repeated measurements with the intervention as a covariate. RESULTS: Thirteen participants were allocated to control and intervention. One participant (intervention) dropped out after min 7 because of exhaustion. Primary outcome showed a mean compression depth of 44.1 mm, with an inter-individual standard deviation (SDb) of 13.0 mm and an intra-individual standard deviation (SDw) of 6.7 mm for the control group vs. 46.1 mm and a SDb of 9.0 mm and SDw of 10.3 mm for the intervention group (difference: 1.9; 95% confidence interval -6.9 to 10.8; p = 0.66). Secondary outcomes showed no difference for exhaustion and CPR-quality values. CONCLUSIONS: There is no difference in compression depth, quality of CPR, or physical strain on lay rescuers using the initial instruction "push as hard as you can" vs. the standard MPDS(®) instruction "push down firmly 5 cm."

Strategic target temperature management in myocardial infarction--a feasibility trial.

OBJECTIVE: The purpose of this study was to demonstrate the feasibility of a combined cooling strategy started out of hospital as an adjunctive to percutaneous coronary intervention (PCI) in the treatment of ST-elevation acute coronary syndrome (STE-ACS). DESIGN: Non-randomised, single-centre feasibility trial. SETTING: Department of emergency medicine of a tertiary-care facility, Medical University of Vienna, Vienna, Austria. In cooperation with the Municipal ambulance service of the city of Vienna. PATIENTS: Consecutive patients with STE-ACS presenting to the emergency medical service within 6 h after symptom onset. INTERVENTIONS: Cooling was initiated with surface cooling pads in the out-of-hospital setting, followed by the administration of 1000-2000 mL of cold saline at hospital arrival and completed by endovascular cooling in the catheterisation laboratory. MAIN OUTCOME MEASURES: Feasibility of lowering core temperature below 35.0°C prior to immediately performed revascularisation. Safety and tolerability of the cooling procedure. RESULTS: In enrolled 19 patients (one woman, median age 51 years (IQR 45-59)), symptom onset to first medical contact (FMC) was 45 min (IQR 31-85). A core temperature below 35.0°C at reperfusion of the culprit lesion was achieved in 11 patients (78%) within 100 min (IQR 90-111) after FMC without any cooling-related serious adverse event. Temperature could be lowered from baseline 36.4°C (IQR 36.2-36.5°C) to 34.4°C (IQR 34.1-35.0°C) at the time of reperfusion. CONCLUSIONS: With limitations an immediate out-of-hospital therapeutic hypothermia strategy was feasible and safe in patients with STE-ACS undergoing primary PCI. CLINICAL TRIAL REGISTRATION: http://www.clinicaltrials.gov/ct2/show/NCT01864343; clinical trials unique identifier: NCT01864343.

Dispatchers impression plus Medical Priority Dispatch System reduced dispatch centre times in cases of out of hospital cardiac arrest. Pre-alert--a prospective, cluster randomized trial.

AIM OF THE STUDY: Dispatch centre processing times for out-of-hospital cardiac arrest or critically ill patients should be as short as possible. A modified 'pre-alert' dispatch workflow might be able to improve the processing time. METHODS: Between October 2010 and May 2011 dispatch events, suspicious for cardiac arrest, were prospectively randomized in 24h clusters. The emergency medical service of the intervention group got, based on the dispatchers impression, a 'pre-alert' alarm-message followed by the standard Medical Priority Dispatch System query whereas the control group did not. RESULTS: In 225 clusters 1500 events were eligible for analysis. Data are presented as median and 25-75 interquartile ranges. Per-protocol analysis demonstrated for the intervention group on 'pre-alert' days a median processing time of 143 s (109-187; n=256) versus 198 s (167-255; n=502) in the control group on non 'pre-alert' days, with a difference of 0.23 log-seconds (p<0.001; 95% CI 0.74-0.28). In critical ill patients, intention-to-treat analysis showed for the intervention group a median of 168 s (131-264; n=153) versus 239 s (176-309; n=164) in the control group, with a difference of 1.4 log-seconds (p<0.001; 95% CI 1.25-1.55). CONCLUSION: Dispatch times can effectively be reduced in cases of out-of-hospital cardiac arrest or critical ill patients with a 'pre-alert' dispatch workflow in combination with the Medical Priority Dispatch System protocol. This might play an important role in improving patient care.

An electrocardiogram technician improves in-hospital first medical contact-to-electrocardiogram times: a cluster randomized controlled interventional trial.

BACKGROUND: In the case of chest pain, the current guidelines require electrocardiogram (ECG) recording and patient assessment within 10 minutes upon arrival in the emergency department. METHODS: We investigated the effect of an ECG technician (ECG-T) on in-hospital first medical contact-to-ECG times (iFMC-to-ECG) investigated in a cluster randomized, controlled trial. Allocation of intervention was concealed. Staff satisfaction and feasibility was defined as a secondary outcome. Delays between ECG and the availability of an emergency physician and the assessment of ECG were additionally evaluated. RESULTS: A total of 163 (44 clusters) and 191 (47 clusters) patients were allocated to control and intervention, respectively. Twenty-seven (17%) of 163 patients in the control group vs 110 (58%) of 191 patients in the intervention group received ECG registration within 10 minutes (risk ratio, 3.40 [2.24-5.15]; P < .001). The iFMC-to-ECG time was 23 (95% confidence interval [CI], 20-27) minutes for the control group vs 9 (95% CI, 8-11) minutes for the intervention group (P < .001). Nursing staff judged the feasibility of intervention with a median of 1 (interquartile range [IQR], 1-1 (on a scale of 1 [best] to 5 [worst]), perceived workload alleviation with a median of 1 (IQR, 1-1), and improvement of quality of care with a median of 1 (IQR, 1-2). The ECG-to-EP time was 78 (95% CI, 64-92) seconds, and diagnosis was made within 17 (95% CI, 16-18) seconds. CONCLUSIONS: Delays of iFMC-to-ECG can be effectively addressed by implementation of an ECG-T. The service of an ECG-T is feasible and improves staff satisfaction. Both ECG-to-EP time and ECG assessment constitute no relevant delay.