Use of bitemporal NACA score documentation in prehospital emergency medical services- a retrospective study.

BACKGROUND: The assessment of illness severity in the prehospital setting is essential for guiding appropriate medical interventions. The National Advisory Committee for Aeronautics (NACA) score is a validated tool commonly used for this purpose. However, the potential benefits of using bitemporal documentation of NACA scores to capture the dynamic changes in emergency situations remain uncertain. The objective of this study was to evaluate the potential benefit of bitemporal NACA score documentation in the prehospital setting, specifically in assessing the dynamic changes of emergencies and facilitating quality improvement through enhanced documentation practices. METHODS: In this retrospective study, data from prehospital emergency patients were analyzed who received care from the physician response unit between January 1, 2018, and May 31, 2021. Patient demographics, NACA scores, indications for emergency care, and changes in NACA scores were extracted from medical records. Statistical analyses were performed to examine the associations between NACA scores, emergency categories, indications, and changes in NACA scores. RESULTS: The study included 4005 patients, predominantly categorized as NACA III (33.7% at initial assessment, 41.8% at subsequent assessment) and NACA IV (31.6% at initial assessment, 22.4% at subsequent assessment). There was a significant improvement in NACA scores during the provision of prehospital care (p < 0.01). Notably, prehospital emergencies attributed to internal medical, neurological, traumatic, and paediatric causes demonstrated significant improvements in NACA scores (p < 0.01). Gender-specific differences were also observed. CONCLUSION: Our study suggests that the bitemporal documentation of NACA scores can be advantageous in the prehospital setting and may have implications for research, practice, and policy.

Physician utilization in prehospital emergency medical services in Europe: an overview and comparison. / Visión general y comparación de la presencia de médicos en los servicios de emergencias médicas prehospitalarios en Europa.

OBJECTIVES: National and regional systems for emergency medical care provision may differ greatly. We sought to determine whether or not physicians are utilized in prehospital care and to what extent they are present in differentEuropean countries. MATERIAL AND METHODS: We collected information on 32 European countries by reviewing publications and sending questionnaires to authors of relevant articles as well as to officials of ministries of health (or equivalent), representatives of national societies in emergency medicine, or well-known experts in the specialty. RESULTS: Thirty of the 32 of European countries we studied (94%) employ physicians in prehospital emergency medical services. In 17 of the 32 (53%), general practitioners also participate in prehospital emergency care. Emergency system models were described as Franco-German in 27 countries (84%), as hybrid in 17 (53%), and as Anglo-American in 14 (44%). Multiple models were present simultaneously in 17 countries (53%). We were able to differentiate between national prehospital emergency systems with a novel classification based on tiers reflecting the degree of physician utilization in the countries. We also grouped the national systems by average population and area served. CONCLUSION: There are notable differences in system designs and intensity of physician utilization between different geographic areas, countries, and regions in Europe. Several archetypal models (Franco-German, hybrid, and Anglo- American) exist simultaneously across Europe.

OBJETIVO: Los sistemas nacionales y regionales de prestación de atención médica a las emergencias pueden diferir mucho entre sí. Se buscó dilucidar la presencia de médicos en la atención prehospitalaria y su implantación en los diferentes países europeos. METODO: Se analizaron los datos de 32 países europeos recogidos mediante la revisión de artículos publicados y a través de cuestionarios enviados a los autores de artículos científicos pertinentes, funcionarios del ministerio de sanidad (o equivalente), representantes de sociedades nacionales de medicina de urgencias o expertos reconocidos en medicina de urgencias. RESULTADOS: Treinta de los 32 países europeos investigados (94%) disponen de médicos en los servicios de emergencias prehospitalarios. En 17 de 32 (53%), los médicos generalistas también participan en la atención a las emergencias prehospitalarias. Los modelos de los sistemas de emergencias médicas (SEM) se describieron como francoalemanes en 27 países (84%), híbridos en 17 (53%) o angloamericanos en 14 (44%). En 17 países (53%), coexistían diferentes modelos. Utilizando una nueva forma de clasificación por niveles, basada en la población media y el área atendida por el SEM prehospitalario, se pudieron diferenciar claramente los diferentes modelos existentes. CONCLUSIONES: Se observan notables diferencias en los diseños de los SEM y en la presencia de los médicos entre las diferentes áreas geográficas, países y regiones de Europa. Coexisten varios modelos (francoalemán, híbrido y angloamericano), algunos simultáneamente, en los diferentes países.

Mechanical ventilation with ten versus twenty breaths per minute during cardio-pulmonary resuscitation for out-of-hospital cardiac arrest: A randomised controlled trial.

AIM OF THE STUDY: This study sought to assess the effects of increasing the ventilatory rate from 10 min-1 to 20 min-1 using a mechanical ventilator during cardio-pulmonary resuscitation (CPR) for out-of-hospital cardiac arrest (OHCA) on ventilation, acid-base-status, and outcomes. METHODS: This was a randomised, controlled, single-centre trial in adult patients receiving CPR including advanced airway management and mechanical ventilation offered by staff of a prehospital physician response unit (PRU). Ventilation was conducted using a turbine-driven ventilator (volume-controlled ventilation, tidal volume 6 ml per kg of ideal body weight, positive end-expiratory pressure (PEEP) 0 mmHg, inspiratory oxygen fraction (FiO2) 100%), frequency was pre-set at either 10 or 20 breaths per minute according to week of randomisation. If possible, an arterial line was placed and blood gas analysis was performed. RESULTS: The study was terminated early due to slow recruitment. 46 patients (23 per group) were included. Patients in the 20 min-1 group received higher expiratory minute volumes [8.8 (6.8-9.9) vs. 4.9 (4.2-5.7) litres, p < 0.001] without higher mean airway pressures [11.6 (9.8-13.6) vs. 9.8 (8.5-12.0) mmHg, p = 0.496] or peak airway pressures [42.5 (36.5-45.9) vs. 41.4 (32.2-51.7) mmHg, p = 0.895]. Rates of ROSC [12 of 23 (52%) vs. 11 of 23 (48%), p = 0.768], median pH [6.83 (6.65-7.05) vs. 6.89 (6.80-6.97), p = 0.913], and median pCO2 [78 (51-105) vs. 86 (73-107) mmHg, p > 0.999] did not differ between groups. CONCLUSION: 20 instead of 10 mechanical ventilations during CPR increase ventilation volumes per minute, but do not improve CO2 washout, acidaemia, oxygenation, or rate of ROSC. CLINICALTRIALS: gov Identifier: NCT04657393.

Assessing the weak links - Necessity and impact of regional cardiac arrest awareness campaigns for laypersons.

Introduction: Public knowledge of out-of-hospital cardiac arrest (OHCA), and initiation of basic life support (BLS) is crucial to increase survival in OHCA. Methods: The study analysed the knowledge and willingness to perform BLS of laypersons passing an AED at a public train station. Interviewees were recruited at two time points before and after a four year-long structured regional awareness campaign, which focused on call, compress, shock in a mid-size European city (270,000 inhabitants). Complete BLS was defined as multiple responses for call for help; initiation of chest compressions; and usage of an AED, without mentioning recovery position. Minimal BLS was defined as call for help and initiation of chest compressions. Results: A total of 784 persons were interviewed, 257 at baseline and 527 post-campaign. Confronted with a fictional OHCA, at baseline 8.5% of the interviewees spontaneously mentioned actions for complete BLS and 17.9% post-campaign (p = 0.009). An even larger increase in knowledge was seen in minimal BLS (34.6% vs 60.6%, p < 0.001). Conclusion: After a regional cardiac arrest awareness campaign, we found an increase in knowledge of BLS actions in the lay public. However, our investigation revealed severe gaps in BLS knowledge, possibly resulting in weak first links of the chain of survival.

Data for: Reliability of mechanical ventilation during continuous chest compressions: A crossover study of transport ventilators in a human cadaver model of CPR.

The data presented in this article relate to the research article, "Reliability of mechanical ventilation during continuous chest compressions: a crossover study of transport ventilators in a human cadaver model of CPR" [1]. This article contains raw data of continuous recordings of airflow, airway and esophageal pressure during the whole experiment. Data of mechanical ventilation was obtained under ongoing chest compressions and from repetitive measurements of pressure-volume curves. All signals are presented as raw time series data with a sample rate of 200Hz for flow and 500 Hz for pressure. Additionally, we hereby publish extracted time series recordings of force and compression depth from the used automated chest compression device. Concomitantly, we report tables with time stamps from our laboratory book by which the data can be sequenced into different phases of the study protocol. We also present a dataset of derived volumes which was used for statistical analysis in our research article together with the used exclusion list. The reported dataset can help to understand mechanical properties of Thiel-embalmed cadavers better and compare different models of cardiopulmonary resuscitation (CPR). Future research may use this data to translate our findings from bench to bedside. Our recordings may become useful in developing respiratory monitors for CPR, especially in prototyping and testing algorithms of such devices.

A retrospective cohort study on association of age and physician decision making for or against rapid sequence intubation in unconscious patients.

In unconscious individuals, rapid sequence intubation (RSI) may be necessary for cardiopulmonary stabilisation and avoidance of secondary damage. Opinions on such invasive procedures in people of older age vary. We thus sought to evaluate a possible association between the probability of receiving prehospital RSI in unconsciousness and increasing age. We conducted a retrospective study in all missions (traumatic and non-traumatic) of the prehospital emergency physician response unit in Graz between January 1st, 2010 and December 31st, 2019, which we searched for Glasgow Coma Scale (GCS) below 9. Cardiac arrests were excluded. We performed multivariable regression analysis for RSI with age, GCS, independent living, and suspected cause as independent variables. Of the 769 finally included patients, 256 (33%) received RSI, whereas 513 (67%) did not. Unadjusted rates of RSI were significantly lower in older patients (aged 85 years and older) compared to the reference group aged 50-64 years (13% vs. 51%, p < 0.001). In multivariable regression analysis, patients aged 85 years and older were also significantly less likely to receive RSI [OR (95% CI) 0.76 (0.69-0.84)]. We conclude that advanced age, especially 85 years or older, is associated with significantly lower odds of receiving prehospital RSI in cases of unconsciousness.

Reliability of mechanical ventilation during continuous chest compressions: a crossover study of transport ventilators in a human cadaver model of CPR.

BACKGROUND: Previous studies have stated that hyperventilation often occurs in cardiopulmonary resuscitation (CPR) mainly due to excessive ventilation frequencies, especially when a manual valve bag is used. Transport ventilators may provide mandatory ventilation with predetermined tidal volumes and without the risk of hyperventilation. Nonetheless, interactions between chest compressions and ventilations are likely to occur. We investigated whether transport ventilators can provide adequate alveolar ventilation during continuous chest compression in adult CPR. METHODS: A three-period crossover study with three common transport ventilators in a cadaver model of CPR was carried out. The three ventilators 'MEDUMAT Standard²', 'Oxylog 3000 plus', and 'Monnal T60' represent three different interventions, providing volume-controlled continuous mandatory ventilation (VC-CMV) via an endotracheal tube with a tidal volume of 6 mL/kg predicted body weight. Proximal airflow was measured, and the net tidal volume was derived for each respiratory cycle. The deviation from the predetermined tidal volume was calculated and analysed. Several mixed linear models were calculated with the cadaver as a random factor and ventilator, height, sex, crossover period and incremental number of each ventilation within the period as covariates to evaluate differences between ventilators. RESULTS: Overall median deviation of net tidal volume from predetermined tidal volume was - 21.2 % (IQR: 19.6, range: [- 87.9 %; 25.8 %]) corresponding to a tidal volume of 4.75 mL/kg predicted body weight (IQR: 1.2, range: [0.7; 7.6]). In a mixed linear model, the ventilator model, the crossover period, and the cadaver's height were significant factors for decreased tidal volume. The estimated effects of tidal volume deviation for each ventilator were - 14.5 % [95 %-CI: -22.5; -6.5] (p = 0.0004) for 'Monnal T60', - 30.6 % [95 %-CI: -38.6; -22.6] (p < 0.0001) for 'Oxylog 3000 plus' and - 31.0 % [95 %-CI: -38.9; -23.0] (p < 0.0001) for 'MEDUMAT Standard²'. CONCLUSIONS: All investigated transport ventilators were able to provide alveolar ventilation even though chest compressions considerably decreased tidal volumes. Our results support the concept of using ventilators to avoid excessive ventilatory rates in CPR. This experimental study suggests that healthcare professionals should carefully monitor actual tidal volumes to recognise the occurrence of hypoventilation during continuous chest compressions.

Factors associated with physician decision making on withholding cardiopulmonary resuscitation in prehospital medicine.

This study seeks to identify factors that are associated with decisions of prehospital physicians to start (continue, if ongoing) or withhold (terminate, if ongoing) CPR in patients with OHCA. We conducted a retrospective study using anonymised data from a prehospital physician response system. Data on patients attended for cardiac arrest between January 1st, 2010 and December 31st, 2018 except babies at birth were included. Logistic regression analysis with start of CPR by physicians as the dependent variable and possible associated factors as independent variables adjusted for anonymised physician identifiers was conducted. 1525 patient data sets were analysed. Obvious signs of death were present in 278 cases; in the remaining 1247, resuscitation was attempted in 920 (74%) and were withheld in 327 (26%). Factors significantly associated with higher likelihood of CPR by physicians (OR 95% CI) were resuscitation efforts by EMS before physician arrival (60.45, 19.89-184.29), first monitored heart rhythm (3.07, 1.21-7.79 for PEA; 29.25, 1.93-442. 51 for VF / pVT compared to asystole); advanced patient age (modelled using cubic splines), physician response time (0.92, 0.87-0.97 per minute) and malignancy (0.22, 0.05-0.92) were significantly associated with lower odds of CPR. We thus conclude that prehospital physicians make decisions to start or withhold resuscitation routinely and base those mostly on situational information and immediately available patient information known to impact outcomes.

Atlanto-occipital dislocation in a patient presenting with out-of-hospital cardiac arrest: a case report and literature review.

BACKGROUND: Atlanto-occipital dislocation is a rare and severe injury of the upper spine associated with a very poor prognosis. CASE PRESENTATION: We report the case of a 59-year-old European man who suffered from out-of-hospital cardiac arrest following a motor vehicle accident. Cardiopulmonary resuscitation was initiated immediately by bystanders and continued by emergency medical services. After 30 minutes of cardiopulmonary resuscitation with a total of five shocks following initial ventricular fibrillation, return of spontaneous circulation was achieved. An electrocardiogram recorded after return of spontaneous circulation at the scene showed signs of myocardial ischemia as a possible cause for the cardiac arrest. No visible signs of injury were found. He was transferred to the regional academic trauma center. Following an extended diagnostic and therapeutic workup in the emergency room, including extended focused assessment with sonography for trauma ultrasound, whole-body computed tomography, and magnetic resonance imaging (of his head and neck), a diagnosis of major trauma (atlanto-occipital dislocation, bilateral serial rip fractures and pneumothoraces, several severe intracranial bleedings, and other injuries) was made. An unfavorable outcome was initially expected due to suspected tetraplegia and his inability to breathe following atlanto-occipital dislocation. Contrary to initial prognostication, after 22 days of intensive care treatment and four surgical interventions (halo fixation, tracheostomy, intracranial pressure probe, chest drains) he was awake and oriented, spontaneously breathing, and moving his arms and legs. Six weeks after the event he was able to walk without aid. After 2 months of clinical treatment he was able to manage all the activities of daily life on his own. It remains unclear, whether cardiac arrest due to a cardiac cause resulted in complete atony of the paravertebral muscles and caused this extremely severe lesion (atlanto-occipital dislocation) or whether cardiac arrest was caused by apnea due the paraplegia following the spinal injury of the trauma. CONCLUSIONS: A plausible cause for the trauma was myocardial infarction which led to the car accident and the major trauma in relation to the obviously minor trauma mechanism. With this case report we aim to familiarize clinicians with the mechanism of injury that will assist in the diagnosis of atlanto-occipital dislocation. Furthermore, we seek to emphasize that patients presenting with electrocardiographic signs of myocardial ischemia after high-energy trauma should primarily be transported to a trauma facility in a percutaneous coronary intervention-capable center rather than the catheterization laboratory directly.

Arterial blood gases during and their dynamic changes after cardiopulmonary resuscitation: A prospective clinical study.

PURPOSE: An arterial blood gas analysis (ABG) yields important diagnostic information in the management of cardiac arrest. This study evaluated ABG samples obtained during out-of-hospital cardiopulmonary resuscitation (OHCPR) in the setting of a prospective multicenter trial. We aimed to clarify prospectively the ABG characteristics during OHCPR, potential prognostic parameters and the ABG dynamics after return of spontaneous circulation (ROSC). METHODS: ABG samples were collected and instantly processed either under ongoing OHCPR performed according to current advanced life support guidelines or immediately after ROSC and data ware entered into a case report form along with standard CPR parameters. RESULTS: During a 22-month observation period, 115 patients had an ABG analysis during OHCPR. In samples obtained under ongoing CPR, an acidosis was present in 98% of all cases, but was mostly of mixed hypercapnic and metabolic origin. Hypocapnia was present in only 6% of cases. There was a trend towards higher paO2 values in patients who reached sustained ROSC, and a multivariate regression analysis revealed age, initial rhythm, time from collapse to CPR initiation and the arterio-alveolar CO2 difference (AaDCO2) to be associated with sustained ROSC. ABG samples drawn immediately after ROSC demonstrated higher paO2 and unaltered pH and base excess levels compared with samples collected during ongoing CPR. CONCLUSIONS: Our findings suggest that adequate ventilation and oxygenation deserve more research and clinical attention in the management of cardiac arrest and that oxygen uptake improves within minutes after ROSC. Hyperventilation resulting in arterial hypocapnia is not a major problem during OHCPR.

The Medizinercorps Graz: a 120-year-old institution of emergency medicine.

One year after the establishment of the rescue service of Graz, Austria, in 1889, twelve young medical students were recruited because of the lack of accredited physicians for emergency care, leading to the foundation of the Medizinercorps Graz. This concept of involving medical students in prehospital emergency care has been retained for more than 120 years, and today the Medizinercorps is integrated into the local Red Cross branch, staffing two emergency ambulance vehicles. The responsible medical officer is called Rettungsmediziner and is an advanced medical student with a specialized emergency medical training of more than 3,000 hours, comprising theoretical lectures; in-hospital clerkships in anesthesia, internal medicine, and surgery; manikin training; and hands-on peer-to-peer teaching during assignments. The local emergency medical system provides at least 10 regular basic ambulance vehicles, the two emergency ambulance vehicles, and two emergency physicians on a 24-hours-a-day/seven-days-a-week basis for about 300,000 people. The emergency ambulance vehicles staffed with a Rettungsmediziner respond to all kinds of possibly life-threatening situations and also provide interhospital transfer of intensive care patients. This entirely volunteer-based system enables extremely high-level prehospital emergency care, saves resources and reduces costs, and employs modern training concepts for the continuing advancement of prehospital emergency care.

Increasing arterial oxygen partial pressure during cardiopulmonary resuscitation is associated with improved rates of hospital admission.

AIM: As recent clinical data suggest a harmful effect of arterial hyperoxia on patients after resuscitation from cardiac arrest (CA), we aimed to investigate this association during cardiopulmonary resuscitation (CPR), the earliest and one of the most crucial phases of recirculation. METHODS: We analysed 1015 patients who from 2003 to 2010 underwent out-of-hospital CPR administered by emergency medical services serving 300,000 inhabitants. Inclusion criteria for further analysis were nontraumatic background of CA and patients >18 years of age. One hundred and forty-five arterial blood gas analyses including oxygen partial pressure (paO2) measurement were obtained during CPR. RESULTS: We observed a highly significant increase in hospital admission rates associated with increases in paO2 in steps of 100 mmHg (13.3 kPa). Subsequently, data were clustered according to previously described cutoffs (≤ 60 mmHg [8 kPa]], 61-300 mmHg [8.1-40 kPa], >300 mmHg [>40 kPa]). Baseline variables (age, sex, initial rhythm, rate of bystander CPR and collapse-to-CPR time) of the three compared groups did not differ significantly. Rates of hospital admission after CA were 18.8%, 50.6% and 83.3%, respectively. In a multivariate analysis, logistic regression revealed significant prognostic value for paO2 and the duration of CPR. CONCLUSION: This study presents novel human data on the arterial paO2 during CPR in conjunction with the rate of hospital admission. We describe a significantly increased rate of hospital admission associated with increasing paO2. We found that the previously described potentially harmful effects of hyperoxia after return of spontaneous circulation were not reproduced for paO2 measured during CPR. CLINICAL TRIAL REGISTRATION: n/a.

Cardiac movement identified on prehospital echocardiography predicts outcome in cardiac arrest patients.

INTRODUCTION: The prognostic value of emergency echocardiography (EE) in the management of cardiac arrest patients has previously been studied in an in-hospital setting. These studies mainly included patients who underwent cardiopulmonary resuscitation (CPR) by emergency medicine technicians at the scene and who arrived at the emergency department (ED) still in a state of cardiac arrest. In most European countries, cardiac arrest patients are normally treated by physician-staffed emergency medical services (EMS) teams on scene. Transportation to the ED while undergoing CPR is uncommon. OBJECTIVE: To evaluate the ability of EE to predict outcome in cardiac arrest patients when it is performed by ultrasound-inexperienced emergency physicians on scene. METHODS: We performed a prospective, observational study of nonconsecutive, nontrauma, adult cardiac arrest patients who were treated by physician-staffed urban EMS teams on scene. Participating emergency physicians (EPs) received a two-hour course in EE during CPR. After initial procedures were accomplished, EE was performed during a rhythm and pulse check. A single subxiphoid, four-chamber view was required for study enrollment. We defined sonographic evidence of cardiac kinetic activity as any detected motion of the myocardium, ranging from visible ventricular fibrillation to coordinated ventricular contractions. The CPR had to be continued for at least 15 minutes after the initial echocardiography. No clinical decisions were made based on the results of EE. RESULTS: Forty-two patients were enrolled in the study. The heart could be visualized successfully in all patients. Five (11.9%) patients survived to hospital admission. Of the 32 patients who had cardiac standstill on initial EE, only one (3.1%) survived to hospital admission, whereas four out of 10 (40%) patients with cardiac movement on initial EE survived to hospital admission (p = 0.008). Neither asystole on initial electrocardiogram nor peak capnography value, age, bystander CPR, or downtime was a significant predictor of survival. Only cardiac movement was associated with survival, and cardiac standstill at any time during CPR resulted in a positive predictive value of 97.1% for death at the scene. CONCLUSION: Our results support the idea of focused echocardiography as an additional criterion in the evaluation of outcome in CPR patients and demonstrate its feasibility in the prehospital setting.