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Description / Table of Contents: Summary Chest compressions are a simple and efficient measure during CPR and well established since many years. However, whether they lead to serious complications yet needs to be answered. Among them thoracic fractures and injuries of inner organs (cardiac, hepatic, splenic) are well known. Additionally fat embolism of the lungs as well as other organs have been described. Concerning the pathogenesis different theories are discussed in the literature. This article reviews the most relevant literature of the last decades. Studies focusing on fat embolism have especially been carried out in trauma surgery and pathology. The actual incidence of fat embolism during trauma, long bone surgery, shock and CPR seems to be rather high. However a clinical manifestation is rarely apparent. Especially after (unsuccessful) CPR pathological studies revealed the degree of fat embolism to be rather low. Because specific studies on the incidence of fat embolism during CPR lack completly, the significance for CPR is unknown and can only be speculated on.

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 Objectives: The cardiotoxic properties of bupivacain have been well documented under in-vitro, as well as under in-vivio conditions. A further mechanism of cardiovascular impairment by bupivacaine via the central nervous system gained investigational interest in animal studies. The aim of our study was to demonstrate the effect of a ventriculocisternal perfusion of bupivacain on systemic hemodynamic variabels and their reversability by wash-out with mock-CSF. Methods: After obtaining animal investional commitee consent, nine anaesthetized and relaxated pigs were prepared for a ventriculocisternal perfusion (VCP). Hemodynamic data were obtained by invasive blood pressure measurements in the high and low pressure system as well as cardiac output (thermodilution technique), intracranial pressure and electrocardiogram. Systemic vascular resistance and stroke volume were calculated using standard formulas. A second group of three animals were exposed to an intravenous infusion of the same dose of bupivacain over the same period of time to rule out direct cardiac effects. After instrumentation baseline data were obtained (KO 1) under VCP with mock-CSF for 30 minutes. The mock-CSF was replaced by 0,05% bupivacaine in mock-CSF and VCP was continued with 3 ml · h–1 for 20 minutes. After adminstration of 500 µg bupivacaine data were collected (BU). The bupivacaine solution was replaced by mock-CSF and after twenty minutes hemodynamic measurement were repeated (KO2). Results: The intravenous adminstration of 500µg bupivacaine had no effect on all measured variables. VCP of the same dose resulted in significant increase in heart rate, systolic, diastolic and mean arterial blood pressures. Left and right heart filling pressures as well as systemic vascular resistance were not affected while the stroke volume decreased. After continuation of VCP with mock-CSF hemodynamic changes were reversed. Discussion: Our results demonstrate that bupivacaine initiates an indirect cardiovascular stimulating effect of a VCP with 500 µg of bupivacaine via the central nervous system. The intravenous administration of the same dose had no effect. The centrally mediated cardiovascular effect of bupivacaine was reversed by wash-out with mock-CSF. The cardiovascular stimulation observed in this animal experiment may be of clinical relevance as a potential sign of toxic effects of bupivacaine on the CNS.

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.