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Description / Table of Contents: Abstract Evidence Based (Emergency) Medicine (EB(E)M is a term referring to the application into daily clinical practice of only those methods, procedures, medications etc. which are based on scientific evidence.Where diagnostic and therapeutic principles have not been validated on a prospective, controlled randomised basis, this should be tried out at a later time, if at all possible. This concept may allow to bridge the gap between research and clinical practice, and represents the major goal of EB(E)M. Protagonists of EBEM are at times confronted with criticism that EBEM does not constitute the only but one out of several possible approaches to quality controlled medical care. The fact that more than 50% of all emergency procedures are not evidence based give rise to the question as to whether the performance of randomised controlled studies is ethically justifiable, if control groups are included whose treatment leaves out generally recommended and recognised (though not evidence based) therapeutic and/or diagnostic principles. The following examples may enumerate some of the procedures, methods or medications, respectively, without proven scientific evidence: ·*Medication for resuscitation of cardiac arrest victims ·*Medication for acute asthmatic attacks ·*Initial treatment of uncontrolled haemorrhagic shock ·*Endotracheal intubation in VF/VT ·*The principle need for initial ventilation and the volumes of ventilation in cardiac arrest patients ·*Effectivenes of ACD- and VEST-CPR. A few typical examples are presented to illustrate the requirements of current study designs which have to be met before results of an evaluation are accepted by the EBEM scientists to obtain approval for application of a procedure, method or medication in clinical practice (large patient numbers, power calculations, ethical issues) as well as their benefits and drawbacks.

Description / Table of Contents: Abstract A paper published in various US journals on Emergency Medicine in 1997 [9], has raised considerable concerns. The authors [9] question if it is justified to continue to recommend initial ventilation as part of basic CPR when performed by lay-bystanders. A few aspects need to be discussed and some questions have to be answered before any changes in the current recommendations may even be considered: e.g. 1. How convincing does the available evidence support the following hypotheses: 1.1. Lay CPR without mouth-to-mouth-ventilation provides better outcome after cardiac arrest than lay CPR with mouth-to-mouth-ventilation. 1.2. Endotracheal intubation may be detrimental in patients suffering from hemodynamic compromises, particularly from VF [46]. 2. Is it scientifically and ethically acceptable to design and perform prospective randomized controlled trials(RCTs) to evaluate the efficacy of those components of BCLS and ACLS which have in accordance with AHA-, ERC Guidlines and ILCOR Statements in the past been applied in millions of cardiac arrest victims and have obviously enabled the patients to lead a meaningsful life after survival; under conditions of the proposed study design patients of the study group would be left without the treatment option ventilation, thus diminishing their chances of survival. Ad 1: The arguments presented by the authors are hardly convincing. The authors themselves state elsewhere that reluctance to perform mouth-to-mouth-ventilation should not represent a major problem because most cardiac arrests of cardiac etiology occur at home and in the presence of a relative or friend. Moreover, unreliable recommendations for mouth-to-mouth-ventilation(AHA) [4], lack of training, retention of skills and knowledge, and a deficit in motivation include the main causes of the disappointingly low figures of bystander CPR worldwide. This situation cannot be improved simply by eliminating a lifesaving component of CPR-ventilation. Instead, the proposal to abandon the administration of unreasonably high ventilation volumens (800–1200 ml/breath) from the present guidlines and to recommend volumes ranging from 400–500 ml/breath recently made by the ERC should be given serious consideration. Furthermore, equipment and training manikins need to be adapted to these more reasonable volumes. Independently of the mechanisms of slow decreases in SaO2 after cardiac arrest (provided no compressions are performed) independently of gasping,ventilatory effects of standard compression or ACD-HCPR in the absence of mouth-to-mouth-ventilation, it is essential to realise that the patient’s airways need to be maintained open at all times (this is unlike animal experiments where the airways are primarily kept open by the respective tissue structures): The minimum requirement of First Responder CPR is the guarantee that open airways are maintained. It may possibly be discussed if the present sequence of ABC might be changed to CAB, a practice adopted in the Netherlands many years ago, however, outcome trials an CAB have not been published to date. In addition, greater demands should be made of training requirements in BLS, attendance of refresher courses should be required, and other groups of the population should be included into these programmes than only relatives or friends of patients at risk of a cardiac arrest. The programmes need to be made mandatory for greater variety of groups and individuals to increase the efficacy and efficiency of bystander resuscitation. The hypotheses made by the above-mentioned authors are neither scientifically nor ethically acceptable. Ad 2: Pepe’s argument [46] regarding the efficacy of endotracheal intubation (ETI)in VF-patients has not been scientifically proven and lacks conclusive evidence. ETI serves to protect the airways and lungs against aspiration of regurgitated material and to facilitate artificial ventilation including PEEP, both under anaesthesia and resuscitation. The efficacy of ETI in the OR has long been proven in RCTs. There is therefore no reason to believe that the protective capabilities of ETI are in any way different for anaesthesia or CPR. There is thus no need to require RCTs which would place one group of patients at a gtreater risk of mortality from aspiration (under conditions which do not permit intubation) than any other group just because somebody is interested in finding out if there is a higher mortality rate in one group of VF patients which is due to a greater percentage of patients dying from aspiration than from VF. Based on these considerations it follows that the RCTs postulated by Becker e.a. are neither scientifically nor economically or ethically justified apart from the fact that in the German speaking countries not a single ethics committee would agree to a study design similar to that described by Becker e.a.

Description / Table of Contents: Abstract Selecting a route for drug administration during CPR requires consideration of the speed with which access can be obtained, the technical difficulties involved in performing the procedure, the associated risk of complications, delays in drug delivery to the central circulation, and the duration of effective drug levels following injection. The peripheral venous route is the safest method, and drug delivery can be enhanced by a fluid bolus after injection of the medication. The circulation time is shortest after central venous injection, but there is some risk of complications. The femoral route is associated with a high incidence of unsuccessful catherization. The endotracheal tube provides an accessible route for administration of most drugs, but peak concentrations are lower than those obtained by other routes. While the results are almost the same as an intravenous injection, the intraosseous route is currently underrepresented in clinical practice. This method must not only be considered in pediatric patients, but in adult patients as well.

Description / Table of Contents: Abstract The current increase in the cost of health care must be considered as a severe threat to the prehospital emergency services system. Two examples have been selected – the patient with polytrauma and the patient in cardiac arrest – to demonstrate the dilemma between a need for objective data and the requirements of emergency patients. Study results obtained in trauma patients indicating that total prehospital time, including scene time, is correlated to patient outcome have led to the conclusion that at the scene treatment by emergency physicians may be dispensable. It has, however also been demonstrated that the time required for medical treatment at the scene is equivalent to 20% of the total scene time, thus representing only a fraction of the total prehospital time. Correlating the total prehospital time or scene time to outcome therefore appears absurd. The treatment principle of aggressive shock treatment in polytrauma needs critical reevaluation on the basis of results obtained by recent preclinical studies in patients with penetrating torso injuries. Small volume resuscitation could not be demonstrated to improve outcome in polytrauma patients, although a slight improvement in patients with brain injury may be assumed. Endotracheal intubation and early artificial ventilation are proven therapeutic principles in polytraumatized patients. Unfortunately, for ethical reasons randomised carefully controlled comparative studies can not be performed in polytrauma patients unless the patient is fully conscious. The importance of endotracheal intubation and artificial ventilation in unconscious trauma patients becomes apparent under conditions of anaesthesia where the application of the endotracheal tube averts regurgitation, aspiration and concomitant morbidity and mortality. The common causes of cardiovascular collapse and their pathomechanisms, as well as the mechanisms of cardiopulmonary resuscitation, have been widely investigated. Nevertheless, various aspects of their application are still controversial. The most recent study results have recommended initial ventilation prior to thoracic compression. New methods of assisting mechanical cardiopulmonary resuscitation, such as ACD CPR or vest CPR, have shown promising results in animal experiments. However, the importance of results obtained by preclinical randomised controlled investigations in humans need to be confirmed by further studies as to outcome. The efficacy of defibrillation in cases of ventricular fibrillation has been clearly demonstrated, particularly with a view to the interval between ventricular fibrillation and defibrillation. It has further been demonstrated that basic cardiopulmonary resuscitation preserves ventricular fibrillation and thus improves the chance of survival. The present generation of defibrillators has been further improved, particularly by the introduction of biphasic defibrillator wave forms, which may reduce the required energy, as well as possible complications, while offering an increase in the efficacy of defibrillation and a reduction in defibrillator size. Scientific emergency medicine is responsible not only for the development and validation of new methods and concepts, but in particular for their application under quality control conditions. Politicians require an improvement in the quality of the validation of emergency measures, although the instruments available for the investigation of these measures are known to be obsolete (experimental models, experimental design). Additionally, the financial support of research in emergency medicine suffers from being accourded low priority by public research funds such as the German Research Fund. However, in view of the rapid application of experimental results to daily practice it should be emphasized that patients also support research in emergency medicine via their direct financial contributions to the health insurance companies.

Description / Table of Contents: Abstract Neurogenic pulmonary edema (NPE) is a rare but always life-threatening complication in patients with central nervous system lesions. NPE is evident if patients shortly after cerebral lesions suddenly develop pulmonary edema and other causes of the symptoms, such as aspiration of gastric content, congestive heart failiure and direct toxic exposure, are ruled out. Methods: The current body of literature, partially obtained by computer-guided search (Winspirs) regarding epidemiology, pathophysiology and therapy of NPE was reviewed. Additionally, the case of a patient who developed a sudden pulmonary edema after an episode of tonic-clonic seizures is analyzed. We first provide information about history, definition, incidence and mortality of NPE. Second, a case report of a postictal NPE is presented to illustrate the clinical picture of NPE, and the applied therapeutic strategies are discussed. Third, recent pathophysiologic concepts about symptoms and possible therapeutic principles are reviewed. Fourth, a rational therapeutic plan for the prehospital emergency therapy of NPE is outlined. Results: The different ethiologies all have one characteristic feature: an acute emergency which causes increased intracerebral pressure (ICP). NPE is known in patients after cerebral trauma, intracranial hemorrhage, stroke, intracranial tumor or seizures. The incidence is estimated at around 1% after cerebral trauma, at 71% after cerebral hemorrhage and at 2% after seizures. Mortality is appraised to lie between 60 and 100%, independent of etiology. There is a definite pathophysiologic sequence leading to NPE: a central nervous system lesion causes a sudden increase in ICP which triggers an upregulation of sympathetic signal transduction to assure brain perfusion. Increased tonus of venous and arterial vessels and of myocardial function are the immediate consequences. However, if systemic vascular resistance (SVR) increases excessively, left ventricular failure and finally pulmonary edema (NPE) may result. Additionally, the protein-rich edema fluid points to an increased endothelial permeability within the pulmonary circuit. This is thought to be caused by the acute pressure increase and by neurohumoral mechanisms, possibly similar to those described for the systemic inflammatory response syndrome (SIRS). The most important central nervous system structures involved in NPE are the medulla oblongata and the hypothalamus. Conclusion: NPE is always a life-threatening symptom after increased ICP, where immediate therapeutic interventions are imperative. A rational therapeutic approach needs to be focused on decreasing ICP as primary goal. Additionally, attempts should be made to optimize body oxygenation, decrease pre- and afterload and increase myocardial contractility. Postictal patients suspicious for incipient ventilation problems must be admitted to hospital for further evaluation.

Description / Table of Contents: Zusammenfassung Für die Reanimation nach Herzkreislaufstillstand ist nur „evidence based“, daß – mit Sauerstoff die Oxigenierung verbessert, – mit elektrischer Defibrillation Kammerflimmern beendet – und mit Thorax- bzw. Herzkompression nach Asystolie/PEA ein perfundierender Rhythmus wiederhergestellt werden kann. Alle anderen Maßnahmen der Kardiopulmonalen Reanimation werden in Frage gestellt. Derzeit sind grundsätzlich neuartige „evidence based“ Konzepte der CPR für die prä- bzw. innerklinische Praxis nicht erkennbar. Ansätze zur Verbesserung der Reanimationsergebnisse bieten allenfalls: 1. Die Elimination oder zumindestens deutliche Rückstufung des PulseCheck zur Zeitersparnis. 2. Bei Schnappatmung ggfls. Einführung der CAB sequenz. 3. Änderung des empfohlenen Beatmungsvolumens. Dadurch wird die Erlernbarkeit auch für den Laien entscheidend erleich-tert. 4. Die ACD CPR hat nicht die Verbesserung der Ergebnisse gebracht, die ursprünglich erwartet worden war. Sie kann aber bei PEA und Asystolie ggfls. erfolgversprechend eingesetzt werden. 5. Die VEST CPR befindet sich prä- wie innerklinisch in der Experimentierphase. Tendenziell positive Ergebnisse müssen sich in der prä- und innerklinischen Realität bestätigen. 6. Die Biphasische Defibrillation sollte in der Prähospitalphase die monophasische ablösen und in der Klinik ergänzen. 7. Zu Katecholaminen, Puffern und Antiarrhythmika sind derzeit keine neuen „evidence based“ Empfehlungen möglich. 8. Die für Qualitätskontrolle und Reanimationsforschung erarbeiteten Utstein Style Dokumentationstemplates sollen einen besseren Vergleich der Ergebnisse inner- und außerklinischer Re-animationen zwischen verschiedenen Zentren, aber auch Schwachstellenanalysen und damit verläßlichere Outcomedaten möglich machen, als das bisher der Fall war.