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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.