Umsetzung der Reanimationsleitlinien 2005 in der studentischen Lehre

November 28^th 2005 the revised guidelines for resuscitation have been published by the European Resuscitation Council (ERC). Subsequently the modifications and innovations not only had to be passed on to lay persons and professionals but also as soon as possible to medical students. With commencement of the new regulations for the license to practice medicine (Approbationsordnung für Ärzte) on October 1^st 2003, Emergency Medicine is an independent cross-section subject within the curriculum for a medical degree since summer-semester 2004. With this the structural prerequisites for teaching cardiopulmonary resuscitation according to the guidelines already had been established. Thereby it already has been possible to adapt the content of teaching with the summer-semester 2006. This article describes what methods are feasible to teach cardiopulmonary resuscitation according to the ERC guidelines 2005, how they can be examined and what efforts are necessary for realization.     

The mangled extremity. When to amputate?

To determine indications for immediate or delayed amputation of the mangled lower extremity, we reviewed the cases of 80 patients. Vascular, neurologic, bone, and soft-tissue status were reviewed, as were postoperative complications, requirements for mechanical ventilation, fluid balance, delayed amputation, and survival. Although neurologic, bone, and soft-tissue status did influence decisions regarding immediate amputation, they had little to do with delayed loss of limb or life. The circulation, as determined by the presence or absence of a palpable or Doppler-detected pulse, however, was critical. Of six patients in whom salvage was attempted and in whom fluid balances of greater than 3 L were detected in the first 24 hours post-operatively, five eventually required amputation. Salvage should usually be attempted if a distal pulse is present. If no distal pulse is present, the decision for immediate amputation should be based on functional prognosis. In cases in which salvage is attempted, amputation should be performed at 24 hours if the patient's condition, including a markedly positive fluid balance, indicates systemic compromise. In the absence of a distal pulse on presentation, the eventual amputation rate is high.     

Cumulative ligand activity of NODAL mutations and modifiers are linked to human heart defects and holoprosencephaly

The cyclopic and laterality phenotypes in model organisms linked to disturbances in the generation or propagation of Nodal-like signals are potential examples of similar impairments resulting in birth defects in humans. However, the types of gene mutation(s) and their pathogenetic combinations in humans are poorly understood. Here we describe a mutational analysis of the human NODAL gene in a large panel of patients with phenotypes compatible with diminished NODAL ligand function. Significant reductions in the biological activity of NODAL alleles are detected among patients with congenital heart defects (CHD), laterality anomalies (e.g. left–right mis-specification phenotypes), and only rarely holoprosencephaly (HPE). While many of these NODAL variants are typical for family-specific mutations, we also report the presence of alleles with significantly reduced activity among common population variants. We propose that some of these common variants act as modifiers and contribute to the ultimate phenotypic outcome in these patients; furthermore, we draw parallels with strain-specific modifiers in model organisms to bolster this interpretation.     

Usefulness of a molecular strategy for the detection of bacterial DNA in patients with severe sepsis undergoing continuous renal replacement therapy

INTRODUCTION: Sepsis is a major cause of morbidity and mortality in critically ill patients. Sepsis is associated with cell necrosis and apoptosis. Circulating plasma levels of DNA have been found in conditions associated with cell death, including sepsis, pregnancy, stroke, myocardial infarction and trauma. Plasma DNA can also derive from bacteria. We have recently implemented a method to detect bacterial DNA and, in the present study, we validated this technique comparing it to standard blood culture in terms of diagnostic efficacy. METHODS: We examined a cohort of 9 critically ill patients with a diagnosis of severe sepsis and acute renal failure requiring continuous renal replacement therapy (CRRT). We analyzed bacterial DNA in blood, hemofilters, and ultrafiltrate (UF) by polymerase chain reaction amplification of 16S rRNA gene sequence analysis. Standard blood cultures were performed for all patients. RESULTS: The blood cultures from 2 of the 9 (22%) patients were positive. However, bacterial DNA was identified in the blood of 6 patients (67%), including the 2 septic patients with positive blood cultures. In 9 (100%) patients bacterial DNA was found on the filter blood side, whereas in 7 (78%) subjects it was found in the dialysate compartment of the hemofilters. Bacterial DNA was never detected in the UF. CONCLUSIONS: Using the 16S rRNA gene, the detection of bacterial DNA in blood and adsorbed within the filter could be a useful screening tool in clinically septic, blood culture-negative patients undergoing CRRT. However, the identification of the etiologic agent is not feasible with this technique because specific primers for the defined bacteria must be used to further identify the suspected pathogenic organisms.     

Direct assignment of EPR spectra to structurally defined iron-sulfur clusters in complex I by double electron–electron resonance

In oxidative phosphorylation, complex I (NADH:quinone oxidoreductase) couples electron transfer to proton translocation across an energy-transducing membrane. Complex I contains a flavin mononucleotide to oxidize NADH, and an unusually long series of iron-sulfur (FeS) clusters, in several subunits, to transfer the electrons to quinone. Understanding coupled electron transfer in complex I requires a detailed knowledge of the properties of individual clusters and of the cluster ensemble, and so it requires the correlation of spectroscopic and structural data: This has proved a challenging task. EPR studies on complex I from Bos taurus have established that EPR signals N1b, N2 and N3 arise, respectively, from the 2Fe cluster in the 75 kDa subunit, and from 4Fe clusters in the PSST and 51 kDa subunits (positions 2, 7, and 1 along the seven-cluster chain extending from the flavin). The other clusters have either evaded detection or definitive signal assignments have not been established. Here, we combine double electron-electron resonance (DEER) spectroscopy on B. taurus complex I with the structure of the hydrophilic domain of Thermus thermophilus complex I. By considering the magnetic moments of the clusters and the orientation selectivity of the DEER experiment explicitly, signal N4 is assigned to the first 4Fe cluster in the TYKY subunit (position 5), and N5 to the all-cysteine ligated 4Fe cluster in the 75 kDa subunit (position 3). The implications of our assignment for the mechanisms of electron transfer and energy transduction by complex I are discussed.     

Thoraxkompression ohne Beatmung bei der Laienreanimation?

Basic life support (BLS) refers to maintaining airway patency and supporting breathing and the circulation, without the use of equipment other than infection protection measures. The scientific advisory committee of the American Heart Association (AHA) published recommendations (online-first) on March 31 2008, which promote a call to action for bystanders who are not or not sufficiently trained in cardiopulmonary resuscitation (CPR) and witness an adult out-of-hospital sudden collapse probably of cardiac origin. These bystanders should provide chest compression without ventilation (so-called compression-only CPR). If bystanders were previously trained and thus confident with CPR, they should decide between conventional CPR (chest compression plus ventilation at a ratio of 30:2) and chest compression alone. However, considering current evidence-based medicine and latest scientific data both the European Resuscitation Council (ERC) and the German Resuscitation Council (GRC) do not at present intend to change or supplement the current resuscitation guidelines "Basic life support for adults". Both organisations do not see any need for change or amendments in central European practice and continue to recommend that only those lay rescuers that are not willing or unable to give mouth-to-mouth ventilation should provide CPR solely by uninterrupted chest compressions until professional help arrives. It is also stressed that the training of young people especially teenagers as lay rescuers should be promoted and the establishment of training programs through emergency medical organizations and in schools should be encouraged.     

Potentials evoked in human and monkey medial temporal lobe during auditory and visual oddball paradigms.

Event-related potentials (ERPs) were recorded from epileptic patients with electrodes chronically implanted in the medial temporal lobe (MTL) and other intracranial locations, and from monkeys with epidural, transcortical, and MTL electrodes. For both humans and monkeys, the eliciting events consisted of trains of auditory or visual stimuli in which a random 10-20% deviated in pitch or pattern from the remaining stimuli. The distribution of ERPs elicited by the rare (oddball) stimuli in both species was similar, consisting of a P3 recorded from the scalp or cortical surface and a slightly later, but temporally overlapping, focal negativity in the hippocampus and nearby MTL structures. The similarity between the patterns of ERPs in humans and monkeys establishes the feasibility of studying the electrogenesis of P3-like activity with detailed intracranial recordings in an animal model. The data also establish that the MTL ERPs in human patients represent a normal neurophysiological process unrelated to epilepsy.