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Introduction: Severe cases of the COVID-19 are often associated with the development of a fulminant sepsis-like state with a concomitant cytokine release syndrome. Recently, immunomodulating approaches to treat such a hyperinflammation have come into focus, including the use of new extracorporeal organ support therapies such as CytoSorb hemoadsorption designed to remove cytokines and other circulating mediators from blood. Patients and methods: Thirteen critically ill COVID-19 patients with ARDS who received either ECMO therapy and/or CRRT with concomitant multiple organ failure were included. Hemoadsorption therapy was initiated once the patient had established—or was at high risk of developing—a hyperinflammatory state with marked hemodynamic instability or progressive lung failure. Levels of inflammatory markers, vasopressor requirements, oxygenation, and ventilation parameters were measured, as well as clinically relevant outcome measures. Results: Combined therapy was associated with a significant reduction in inflammatory mediators, hemodynamic stabilization with a concomitant decrease in requirements for vasoactive substances, and a pronounced improvement in lung function and the need for ventilatory support. Treatment appeared safe and well-tolerated. Conclusions: In this case series of SARS-CoV-2 infected patients admitted to the intensive care unit with ARDS, we report effective interleukin (IL)-6 removal, reduced norepinephrine requirement, and improved lung function while receiving adjuvant, extracorporeal hemoadsorption therapy in the context of a multimodal treatment approach. The presented protocol for CytoSorb initiation may be a good foundation for the development of further prospective studies in the field and may eventually also be applied to other forms of hyperinflammatory ARDS.

Summary Coronavirus disease 2019 (COVID-19) progresses mildly in most of the cases; however, about 5% of the patients develop a severe acute respiratory distress syndrome (ARDS). Of all COVID-19 patients 3% need intensive care treatment, which becomes a great challenge for anesthesiology and intensive care medicine, medically, hygienically and for technical safety requirements. For these reasons, only experienced medical and nursing staff in the smallest grouping possible should be assigned. For these team members, a consistent use of personal protective equipment (PPE) is essential. Due to the immense medical challenges, the following treatment guidelines were developed by the ÖGARI (Österreichische Gesellschaft für Anästhesiologie, Reanimation und Intensivmedizin), FASIM (Federation of Austrian Societies of Intensive Care Medicine) and ÖGIAIN (Österreichische Gesellschaft für Internistische und Allgemeine Intensivmedizin und Notfallmedizin). The recommendations given in this article are to be understood as short snapshots of the moment; all basic guidelines are works in progress and will be regularly updated as evidence levels, new study results and additional experience are gathered.

The timely recognition of sepsis and the prediction of its clinical course are challenging due to the complex molecular mechanisms leading to organ failure and to the heterogeneity of sepsis patients. Treatment strategies relying on a “one-fits-all” approach have failed to reduce mortality, suggesting that therapeutic targets differ between patient subgroups and highlighting the need for accurate analysis of the molecular cascades to assess the highly variable host response. Here, we characterized a panel of 44 inflammatory mediators, including cytokines, chemokines, damage-associated molecular patterns, and coagulation-related factors, as well as markers of endothelial activation in 30 patients suffering from renal failure in the course of sepsis. All patients received continuous veno-venous hemodialysis with either high cut-off filters or with standard filters, and mediators were quantified for all patients at the initiation of dialysis and after 24 h and 48 h. Mediator concentrations in individual patients ranged widely, demonstrating the heterogeneity of sepsis patients. None of the mediators correlated with SAPS III or TISS scores. The overall in-hospital mortality of the study population was 56.7% (57.1% vs. 56.3% for high cut-off vs. standard filter). The two filter groups differed regarding most of the mediator levels at baseline, prohibiting conclusions regarding the effect of standard filters versus high cut-off filters on mediator depletion. The elevation and correlation of damage-associated molecular patterns and markers of endothelial activation gave evidence of severe tissue damage. In particular, extracellular histones were strongly increased and were almost 30-fold higher in nonsurvivors as compared to survivors, indicating their diagnostic and prognostic potential.

Clouds impact the radiative transfer of the Earth's atmosphere and strongly influence satellite measurements in the UV visible and IR spectral ranges. For satellite measurements of trace gases absorbing in the UV/vis spectral range, particularly clouds ultimately determine the vertical sensitivity profile, mainly by reducing the sensitivity for trace gas columns below the cloud. The Mainz Iterative Cloud Retrieval Utilities (MICRU) algorithm is specifically designed to reduce the error budget of trace gas retrievals, such as those for nitrogen dioxide (NO2), which strongly depends on the accuracy of small cloud fractions (CF) in particular. The accuracy of MICRU is governed by an empirical parametrisation of the viewing geometry dependent background surface reflectivity taking instrumental and physical effects into account. Instrumental effects are mainly degradation and polarisation effects, physical effects are due to the anisotropy of the surface reflectivity, e.g. shadowing of plants and sun glitter. MICRU is applied to main science channel (MSC) and polarisation measuring device (PMD) data collected between April 2007 and June 2013 by the GOME-2A instrument onboard the MetOp-A satellite. CF are retrieved at different spectral bands between 374 and 758 nm. The MICRU results for MSC and PMD at different wavelengths are inter-compared to study CF precision and accuracy, which depend on wavelength and spatial correlation. Furthermore, MICRU results are compared to FRESCO (Fast Retrieval Scheme for Clouds from the Oxygen A band) and OCRA (Optical Cloud Recognition Algorithm) operational cloud products. We show that MICRU retrieves small CF with an accuracy of 0.04 or better for the entire 1920 km wide swath with a potential bias between −0.01 and −0.03. CF retrieved at shorter wavelengths are less affected by adverse surface heterogeneities. The comparison to the operational CF algorithms shows that MICRU significantly reduces the dependence on viewing angle, time, and sun glitter. Systematic effects along coasts are particularly small for MICRU due to its dedicated treatment of land and ocean surfaces. The MICRU algorithm is designed for spectroscopic instruments ranging from the GOME to TROPOMI/Sentinel-5P, but is also applicable to UV/vis imagers like, for example, AVHRR, MODIS, VIIRS, and Sentinel-2.

OBJECTIVES This study sought to investigate the outcome of high-risk and inoperable patients with severe symptomatic aortic stenosis undergoing transfemoral transcatheter aortic valve replacement (TAVR) in hospitals with (iOSCS) versus without institutional on-site cardiac surgery (no-iOSCS).BACKGROUND Current guidelines recommend the use of TAVR only in institutions with a department for cardiac surgery on site.METHODS In this analysis of the prospective multicenter Austrian TAVI registry, 1,822 consecutive high-risk patients with severe symptomatic aortic stenosis undergoing transfemoral TAVR were evaluated. A total of 290 (15.9%) underwent TAVR at no-iOSCS centers (no-iOSCS group), whereas the remaining 1,532 patients (84.1%) were treated in iOSCS centers (iOSCS group).RESULTS Patients of the no-iOSCS group had a higher perioperative risk defined by the logistic EuroSCORE (20.9% vs. 14.2%; pCONCLUSIONS Patients undergoing transfemoral TAVR in hospitals without iOSCS had a significantly higher baseline risk profile. After propensity score matching short-and long-term mortality was similar between centers with and without iOSCS. (c) 2018 by the American College of Cardiology Foundation.

The TROPOspheric Monitoring Instrument (TROPOMI) onboard the Copernicus Sentinel-5 Precursor (S-5P) platform will measure ultraviolet earthshine radiances at high spectral and improved spatial resolution (pixel size of 7 km × 3.5 km at nadir) compared to its predecessors OMI and GOME-2. This paper presents the sulfur dioxide (SO2) vertical column retrieval algorithm implemented in the S-5P operational processor UPAS (Universal Processor for UV/VIS Atmospheric Spectrometers) and comprehensively describes its various retrieval steps. The spectral fitting is performed using the differential optical absorption spectroscopy (DOAS) method including multiple fitting windows to cope with the large range of atmospheric SO2 columns encountered. It is followed by a slant column background correction scheme to reduce possible biases or across-track-dependent artifacts in the data. The SO2 vertical columns are obtained by applying air mass factors (AMFs) calculated for a set of representative a priori profiles and accounting for various parameters influencing the retrieval sensitivity to SO2. Finally, the algorithm includes an error analysis module which is fully described here. We also discuss verification results (as part of the algorithm development) and future validation needs of the TROPOMI SO2 algorithm.

Multidisziplinare Arbeitsgruppe (ARGE) Ethik in Anasthesie und Intensivmedizin der Osterreichischen Gesellschaft fur Anasthesiologie, Reanimation, Intensivmedizin (OGARI) Die vorliegende Arbeit soll Arzten Hilfestellung bei Entscheidungen in intensivmedizinischen Grenzbereichen geben. Anhand einer strukturierten Checkliste werden die zwei Saulen jeder medizinischen Entscheidung, die Indikation und der Patientenwille in systematischer Weise abgefragt. Vier Stufen moglicher Therapiezielanderungen werden erlautert und Empfehlungen fur die korrekte Dokumentation von Therapiezielanderungen vorgestellt.

Knowledge of the field of view (FOV) of a remote sensing instrument is particularly important when interpreting their data and merging them with other spatially referenced data. Especially for instruments in space, information on the actual FOV, which may change during operation, may be difficult to obtain. Also, the FOV of ground-based devices may change during transportation to the field site, where appropriate equipment is absent. This paper presents an independent, simple and robust method to retrieve FOV of an instrument during operation, i. e. the two-dimensional sensitivity distribution, sampled on a discrete grid. The method relies on correlated measurements featuring a significantly higher spatial resolution, e. g. by an imaging instrument accompanying a spectrometer. The method was applied to two satellite instruments, GOME-2 and OMI, and a ground-based differential optical absorption spectroscopy (DOAS) instrument integrated in an SO2-camera. For GOME-2, quadrangular FOVs could be retrieved, which almost perfectly match the provided FOV edges after applying a correction for spatial aliasing inherent to GOME-type instruments. More complex sensitivity distributions were found at certain scanner angles, which are probably caused by degradation of the moving parts within the instrument. For OMI, which does not feature any moving parts, retrieved sensitivity distributions were much smoother compared to GOME-2. A 2D super-Gaussian with six parameters was found to be an appropriate model to describe the retrieved OMI FOV. The comparison with operationally provided FOV dimensions revealed small differences, which could be mostly explained by the limitations of our retrieval. For the ground-based DOAS instrument, the FOV retrieved using SO2-camera data was slightly smaller than the flat-disc distribution, which is assumed by commonly used correlation technique. Differences between both methods may be attributed to spatial inhomogeneities. In general, our results confirm the already deduced FOV distributions of OMI, GOME-2 and the ground-based DOAS. It is certainly applicable for degradation monitoring and verification exercises. For satellite instruments, the gained information is expected to increase the accuracy of combined products, where measurements of different instruments are integrated, e. g. mapping of high-resolution cloud information, incorporation of surface climatologies. For the SO2-camera community, the method presents a new and efficient tool to monitor the DOAS FOV in the field.

Differential Optical Absorption Spectroscopy (DOAS) is a well established spectroscopic method to determine trace gases in the atmosphere. During the last decade, passive DOAS, which uses solar radiation scattered in the atmosphere as a light source, has become a standard tool to determine SO2 column densities and emission fluxes from volcanoes and other large sources by ground based as well as satellite measurements. For the determination of SO2 column densities, the structured absorption of the molecule in the 300–330 nm region (due to the A1B1 ← X1A1 transition) is used. However, there are several problems limiting the accuracy of the technique in this particular application. Here we propose to use an alternative wavelength region (360–390 nm) due to the spin-forbidden a3B2 ← X1A1 transition for the DOAS evaluation of SO2 in conditions where high SO2 column densities prevail. We show this range to have considerable advantages in such cases, in particular when the particle content of the plume is high and when measurements are performed at large distances from the area of interest.

Regarding limited availability of organ donors for heart transplantation, it is necessary to discuss optimal donor evaluation and donor management. In this manuscript general donor-related parameters as well as heart-specific parameters are discussed regarding international literature. In addition, "marginal" donors and in contrast "optimal" donors are defined. Donor management including optimal hemodynamic management and additional specific intensive care aspects are presented. Exact donor evaluation allows for matching the organ to the most suitable recipient and is therefore especially in the context of marginal donors a crucial step within transplantation process.

International audience; The Dual Color Localization Microscopy (2CLM) presented here is based on the principles of Spectral Precision Distance Microscopy (SPDM) with conventional fluorochromes under special physical conditions. This technique allows us to measure the spatial distribution of single fluorescently labeled molecules in entire cells with an effective optical resolution comparable to macromolecular dimensions. Here, we describe the application of the 2CLM approach to the simultaneous nanoimaging of cellular structures using two fluorochrome types distinguished by different fluorescence emission wavelengths. The capabilities of 2CLM for studying the spatial organization of the genome in the mammalian cell nucleus are demonstrated for the relative distributions of two chromosomal proteins labeled with autofluorescent GFP and mRFP1 domains. The 2CLM images revealed quantitative information on their spatial relationships down to length-scales of 30 nm.

In the year 2006 over 1000 liver transplantation (LTX) were performed in Austria, Germany and Switzerland. The feasible association of liver failure with pathologic affections of all other organ systems requires a thorough examination of the potential liver host and a carefully guided anaesthesia. A comprehensive monitoring of the patient and an elaborate therapeutic concept is necessary to meet the peculiar pathophysiologic conditions during LTX. This report describes the anaesthesiological relevant aspects of the LTX and provides suitable therapeutic options.

Space observations of the Middle East show that geopolitics and armed conflict have drastically altered air pollution emissions., Nitrogen oxides, released from fossil fuel use and other combustion processes, affect air quality and climate. From the mid-1990s onward, nitrogen dioxide (NO2) has been monitored from space, and since 2004 with relatively high spatial resolution by the Ozone Monitoring Instrument. Strong upward NO2 trends have been observed over South and East Asia and the Middle East, in particular over major cities. We show, however, that a combination of air quality control and political factors, including economical crisis and armed conflict, has drastically altered the emission landscape of nitrogen oxides in the Middle East. Large changes, including trend reversals, have occurred since about 2010 that could not have been predicted and therefore are at odds with emission scenarios used in projections of air pollution and climate change in the early 21st century.

OBJECTIVE Outcome after trauma with severe hemorrhagic shock is still dismal. Since the majority of blood is present in the venous vessels, it might be beneficial to perform venous recruiting via the airway during severe hemorrhagic shock. Therefore, the purpose of our study was to evaluate the effects of negative expiratory pressure ventilation on mean arterial blood pressure, cardiac output, and short-term survival during severe hemorrhagic shock. DESIGN Prospective study in 21 laboratory animals. SETTING University hospital research laboratory. SUBJECTS : Tyrolean domestic pigs. INTERVENTIONS After induction of controlled hemorrhagic shock (blood loss approximately 45 mL/kg), 21 pigs were randomly ventilated with either zero end-expiratory pressure (0 PEEP; n = 7), 5 cm H2O positive end-expiratory pressure (5 PEEP; n = 7), or negative expiratory pressure ventilation (up to -30 cm H2O at the endotracheal tube during expiration; n = 7). MEASUREMENTS AND MAIN RESULTS Mean (+/-sd) arterial blood pressure was significantly higher in the negative expiratory pressure ventilation swine when compared with the 0 PEEP (38 +/- 5 vs. 27 +/- 3 mm Hg; p = .001) and the 5 PEEP animals (38 +/- 5 vs. 20 +/- 6 mm Hg; p < .001) after 5 mins of the experiment. Cardiac output was significantly higher in the negative expiratory pressure ventilation swine when compared with the 0 PEEP (3.1 +/- .4 vs. 1.9 +/- .9 L/min; p = .001) and 5 PEEP animals (3.1 +/- .4 vs. 1.2 +/- .8 L/min; p < .001) after 5 mins of the experiment. All seven negative expiratory pressure ventilation animals, but only three of seven 0 PEEP animals (p = .022), survived the 120-min study period, whereas all seven of seven 5 PEEP animals were dead within 35 mins (p < .001). Limitations include that blood loss was controlled and that the small sample size limits the evaluation of survival outcome. CONCLUSIONS When compared with pigs ventilated with either 0 PEEP or 5 PEEP, negative expiratory pressure ventilation during severe hemorrhagic shock improved mean arterial blood pressure and cardiac output.

Bag-valve-mask ventilation in an unprotected airway is often applied with a high flow rate or a short inflation time and, therefore, a high peak airway pressure, which may increase the risk of stomach inflation and subsequent pulmonary aspiration. Strategies to provide more patient safety may be a reduction in inspiratory flow and, therefore, peak airway pressure. The purpose of this study was to evaluate the effects of bag-valve-mask ventilation vs. a resuscitation ventilator on tidal volume, peak airway pressure, and peak inspiratory flow rate in apneic patients. In a crossover design, 40 adults were ventilated during induction of anesthesia with either a bag-valve-mask device with room air, or an oxygen-powered, flow-limited resuscitation ventilator. The study endpoints of expired tidal volume, minute volume, respiratory rate, peak airway pressure, delta airway pressure, peak inspiratory flow rate and inspiratory time fraction were measured using a pulmonary monitor. When compared with the resuscitation ventilator, the bag-valve-mask resulted in significantly higher (mean+/-SD) peak airway pressure (15.3+/-3 vs. 14.1+/-3 cm H2O, respectively; p=0.001) and delta airway pressure (14+/-3 vs. 12+/-3 cm H2O, respectively; p

Liver splitting increased the number of grafts for paediatric recipients. Usually the two left lateral segments are given to a child and the remaining liver to an adult recipient. Splitting into a right and a left lobe may allow a small adult to benefit from the left lobe while the right lobe goes to another adult recipient. Splitting of paediatric grafts, however, has rarely been performed. We here report on a case where the liver from a 9-year-old donor was ex situ split along the principal fissure creating a right and left lobe which provided grafts for two children aged 2 and 3 years. Immunosuppression consisted of Tacrolimus-based triple drug therapy. Recovery was completely uneventful in both children who are alive and well with normally functioning grafts 11 months following transplantation. These cases demonstrate the feasibility of splitting even paediatric grafts for two small children.

The strategies to ensure safety during ventilation of an unprotected airway are limiting airway pressure and/or inspiratory flow. In this prospective, randomized study we assessed the effect of face mask ventilation with small tidal volumes in the modified mouth-to-bag resuscitator (maximal volume, 500 mL) versus a pediatric self-inflatable bag versus automatic pressure-controlled ventilation in 40 adult apneic patients during induction of anesthesia. The mouth-to-bag resuscitator requires the rescuer to blow up a balloon inside the self-inflating bag that subsequently displaces air which then flows into the patient's airway. Respiratory variables were measured with a pulmonary monitor (CP-100). Mouth-to-bag resuscitator and pressure-controlled ventilation resulted in significantly lower (mean +/- sd) peak airway pressure (8 +/- 2 and 8 +/- 1 cm H(2)O), peak inspiratory flow rate (0.7 +/- 0.1 and 0.7 +/- 0.1 L/s), and larger inspiratory time fraction (33% +/- 5% and 47% +/- 2%) in comparison to pediatric self-inflating bag ventilation (12 +/- 3 cm H(2)O; 1 +/- 0.2 L/s; 27% +/- 4%; all P < 0.001). The tidal volumes were similar between groups. No stomach inflation occurred in either group. We conclude that using a modified mouth-to-bag resuscitator or automatic pressure-controlled ventilation with similar small tidal volumes during face mask ventilation resulted in an approximately 25% reduction in peak airway pressure when compared with a standard pediatric self-inflating bag.

Background Recruitment maneuvers performed in early adult respiratory distress syndrome remain a matter of dispute in patients ventilated with low tidal volumes and high levels of positive end-expiratory pressure (PEEP). In this prospective, randomized controlled study the authors evaluated the impact of recruitment maneuvers after a PEEP trial on oxygenation and venous admixture (Qs/Qt) in patients with early extrapulmonary adult respiratory distress syndrome. Methods After a PEEP trial 30 consecutive patients ventilated with low tidal volumes and high levels of PEEP were randomly assigned to either undergo a recruitment maneuver or not. Data were recorded at baseline, 3 min after the recruitment maneuver, and 30 min after baseline. Recruitment maneuvers were performed with a sustained inflation of 50 cm H2O maintained for 30 s. Results Compared with baseline the ratio of the arterial oxygen partial pressure to the fraction of inspired oxygen (Pao2/Fio2) and Qs/Qt improved significantly at 3 min after the recruitment maneuver (Pao2/Fio2, 139 +/- 46 mm Hg versus 246 +/- 111 mm Hg, P < 0.001; Qs/Qt, 30.8 +/- 5.8% versus 21.5 +/- 9.7%, P < 0.005), but baseline values were reached again within 30 min. No significant differences in Pao2/Fio2 and Qs/Qt were detected between the recruitment maneuver group and the control group at baseline and after 30 min (recruitment maneuver group [n = 15]: Pao2/Fio2, 139 +/- 46 mm Hg versus 138 +/- 39 mm Hg; Qs/Qt, 30.8 +/- 5.8% versus 29.2 +/- 7.4%; control group: [n = 15]: Pao2/Fio2, 145 +/- 33 mm Hg versus 155 +/- 52 mm Hg; Qs/Qt, 30.2 +/- 8.5% versus 28.1 +/- 5.4%). Conclusion In patients with early extrapulmonary adult respiratory distress syndrome who underwent a PEEP trial, recruitment maneuvers failed to induce a sustained improvement of oxygenation and venous admixture.

In der fruhen Phase nach Herztransplantation (HTX), der Zeit intensivster Immunsuppression, haben Patienten ein hohes Infektionsrisiko. Diese retrospektive Kohortenstudie evaluiert die Wirksamkeit einer dreimonatigen antiviralen Cytomegalievirus (CMV)-Prophylaxe. 133 Patienten (Gruppe II: HTX 1997 — April 2003) erhielten eine dreimonatige kombiniert intravenos-orale CMV-Prophylaxe (Ganciclovir-Cymevene®) und wurden mit einer historischen Gruppe I (40 Patienten, HTX 1995-1996; CMV-Prophylaxe: CMV-Hyperimmunglobulin [Cytotect®] im 1. postoperativen Monat; Aciclovir [Zovirax®] oral uber 6 Monate) verglichen. Demographische Daten der Spender und Ernpfanqer beider Gruppen zeigten keine relevanten Unterschiede (ausgenommen cardiale Grunderkrankungen; p=0,016). In beiden Gruppen wurde ein identes immunsuppressives Regime verwendet. In Gruppe II war die Mortalitat hochsignifikant geringer (GI: 37,5%, GIl: 9,8%, p

Reducing inspiratory flow rate and peak airway pressure may be important in order to minimise the risk of stomach inflation when ventilating an unprotected airway with positive pressure ventilation. The purpose of this study was to assess the effects of a newly developed bag-valve-mask device (SMART BAG † , O-Two Systems International, Ont., Canada) that limits peak inspiratory flow. A bench model simulating a patient with an unintubated airway was used consisting of a face mask, manikin head, training lung (lung compliance, 100 ml/cm H2O, airway resistance 4 cm H2O/l/s, lower oesophageal sphincter pressure 20 cm H2O and simulated stomach). Twenty nurses were randomised to each ventilate the manikin using a standard single person technique for 1 min (respiratory rate, 12/min) with either a standard adult self-inflating bag, or the SMART BAG † . The volunteers were blinded to the experimental design of the model until completion of the experimental protocol. The SMART BAG † vs. standard self-inflating bag resulted in significantly (P B/0.05) lower mean9 /S.D. peak inspiratory flow rates (329 /2 vs. 619 /13 l/min), peak inspiratory pressure (129 /2 vs. 179 / 2c m H 2O), lung tidal volumes (5259 /111 vs. 6809 /154 ml) and stomach tidal volumes (09 /0 vs. 179 /36 ml), longer inspiratory times (1.99 /0.3 vs. 1.59 /0.3 s), but significantly higher mask leakage (269 /13 vs. 149 /8%); mask tidal volumes (7009 /104 vs. 7859 /172 ml) were comparable. The mask leakage observed is not an uncommon factor in bag-valve-mask ventilation with leakage fractions of 25/40% having been previously reported. The differences observed between the standard BVM and the SMART BAG † are due more to the anatomical design of the mask and the non-anatomical shape of the manikin face than the function of the device. Future studies should remove the mask to manikin interface and should introduce a standardized mask leakage fraction. The use of a two-person technique may have removed the problem of mask leakage. In conclusion, using the SMART BAG † during simulated ventilation of an unintubated patient in respiratory arrest significantly decreased inspiratory flow rate, peak inspiratory pressure, stomach tidal volume, and resulted in a significantly longer inspiratory time when compared to a standard self-inflating bag. # 2003 Published by Elsevier Science Ireland Ltd.

OBJECTIVE To evaluate patients without prior pulmonary disease after cardiac surgery and to determine whether resistive unloading by automatic tube compensation, pressure support ventilation, and continuous positive airway pressure has different effects on oxygen consumption, breathing pattern, gas exchange, and hemodynamics. DESIGN Prospective, randomized, controlled study. SETTING Tertiary care, postoperative intensive care unit. PATIENTS Twenty-one patients scheduled for open heart coronary artery bypass graft surgery. INTERVENTIONS Each patient was ventilated with all three modes in random order. MEASUREMENTS AND MAIN RESULTS Patients were ventilated in three modes, each applied for 30 mins according to computer-generated randomization: pressure support ventilation with 5 cm H2O, continuous positive airway pressure, and automatic tube compensation. Oxygen consumption was calculated by means of indirect calorimetry. The hypnotic state of the patients was monitored by Bispectral Index. For hemodynamic measurements, a fiberoptic pulmonary artery catheter was inserted. The main finding of our study was that oxygen consumption and breathing pattern (tidal volume and respiratory rate) did not differ significantly during automatic tube compensation and pressure support ventilation compared with continuous positive airway pressure (oxygen consumption, 170 +/- 29 vs. 170 +/- 26 vs. 174 +/- 29 mL.min.m, respectively; tidal volume, 466 +/- 132 vs. 484 +/- 125 vs. 470 +/- 119 mL, respectively; respiratory rate, 16 +/- 4 vs. 15 +/- 4 vs. 16 +/- 4 breaths/min, respectively). Automatic tube compensation and pressure support ventilation had no clinical effects on gas exchange and hemodynamic variables compared with continuous positive airway pressure. None of the variables differed significantly during the three ventilatory settings. CONCLUSION In postoperative tracheally intubated patients with normal ventilatory demand, automatic tube compensation and pressure support ventilation with 5 cm H2O lead to identical oxygen consumption, breathing patterns, gas exchange, and hemodynamics. We, therefore, suggest that this group of patients does not need any additional positive pressure support from the ventilator to overcome the additional work of breathing imposed by the endotracheal tube during the weaning phase from mechanical ventilation.

Introduction Automated control of mechanical ventilation during general anaesthesia is not common. A novel system for automated control of most of the ventilator settings was designed and is available on an anaesthesia machine. Methods and analysis The ‘Automated control of mechanical ventilation during general anesthesia study’ (AVAS) is an international investigator-initiated bicentric observational study designed to examine safety and efficacy of the system during general anaesthesia. The system controls mechanical breathing frequency, inspiratory pressure, pressure support, inspiratory time and trigger sensitivity with the aim to keep a patient stable in user adoptable target zones. Adult patients, who are classified as American Society of Anesthesiologists physical status I, II or III, scheduled for elective surgery of the upper or lower limb or for peripheral vascular surgery in general anaesthesia without any additional regional anaesthesia technique and who gave written consent for study participation are eligible for study inclusion. Primary endpoint of the study is the frequency of specifically defined adverse events. Secondary endpoints are frequency of normoventilation, hypoventilation and hyperventilation, the time period between switch from controlled ventilation to assisted ventilation, achievement of stable assisted ventilation of the patient, proportion of time within the target zone for tidal volume, end-tidal partial pressure of carbon dioxide as individually set up for each patient by the user, frequency of alarms, frequency distribution of tidal volume, inspiratory pressure, inspiration time, expiration time, end-tidal partial pressure of carbon dioxide and the number of re-intubations. Ethics and dissemination AVAS will be the first clinical study investigating a novel automated system for the control of mechanical ventilation on an anaesthesia machine. The study was approved by the ethics committees of both participating study sites. In case that safety and efficacy are acceptable, a randomised controlled trial comparing the novel system with the usual practice may be warranted. Trial registration DRKS DRKS00011025, registered 12 October 2016; clinicaltrials.gov ID. NCT02644005, registered 30 December 2015.

Anesthesia for diagnostic procedures, e.g., MRI measurements, has increasingly used sevoflurane and nitrous oxide in recent years. Sevoflurane and nitrous oxide are known cerebrovasodilatators, however, which potentially interferes with MRI examination of cerebral hemodynamics. To compare the effects of relevant equianesthetic concentrations (0.4 MAC) of both drugs on regional cerebral blood flow (rCBF) and regional cerebral blood volume (rCBV) we used contrast-enhanced magnetic resonance imaging (MRI) perfusion measurement, which has the advantage of providing regional anatomic resolution. Sevoflurane increased rCBF more than did nitrous oxide in all regions except in parietal and frontal gray matter. Nitrous oxide, by contrast, increased rCBV in most of the gray matter regions more than did sevoflurane. In summary we show that, in contrast to nitrous oxide, sevoflurane supratentorially reversed the anterior-posterior gradient in rCBF and typically redistributed rCBF to infratentorial gray matter. In contrast, nitrous oxide increased rCBV more than did sevoflurane. Both inhalational anesthetics had a drug-specific influence on cerebral hemodynamics, which is of importance when interpreting MRI studies of cerebral hemodynamics in anesthetized patients.

The American Heart Association recommends tidal volumes of 700 to 1000 mL during mouth-to-mouth ventilation, but smaller tidal volumes of 500 mL may be of advantage to decrease the likelihood of stomach inflation. Because mouth-to-mouth ventilation gas contains only 17% oxygen, but 4% carbon dioxide, it is unknown whether 500-mL tidal volumes given during rescue breathing may result in insufficient oxygenation and inadequate carbon dioxide elimination. In a university hospital research laboratory, 20 fully conscious volunteer health care professionals were randomly assigned to breathe tidal volumes of 500 or 1000 mL of mouth-to-mouth ventilation gas (17% oxygen, 4% carbon dioxide, 79% nitrogen), or room air control (21% oxygen, 79% nitrogen) for 5 min. Arterial blood gases were taken immediately before, and after breathing 5 min of the experimental gas composition. When comparing 500 versus 1000 mL of mouth-to-mouth ventilation tidal volumes with 500 mL of room air, 500 mL of mouth-to-mouth ventilation tidal volume resulted in significantly (P0.05) lower mean +/- SEM arterial oxygen partial pressure (70 +/- 1 versus 85 +/- 2 versus 92 +/- 3 mm Hg, respectively), and lower oxygen saturation (94 +/- 0.4 versus 97 +/- 0.2 versus 98 +/- 0.2%), but increased arterial carbon dioxide partial pressure (46 +/- 1 versus 40 +/- 1 versus 39 +/- 1 mm Hg, respectively). Sixteen of 20 volunteers had to be excluded from the experiment with 500 mL of mouth-to-mouth ventilation gas after about 3 min instead of after 5 minutes as planned because of severe nervousness, sweating, and air hunger. We conclude that during simulated mouth-to-mouth ventilation, only large (approximately 1000 mL), but not small (approximately 500 mL) tidal volumes were able to maintain both sufficient oxygenation and adequate carbon dioxide elimination.To provide efficient mouth-to-mouth ventilation, it is important to administer tidal volumes of 1000 mL; tidal volumes of 500 mL were not adequate.

The use of sevoflurane is favored for its rapid onset and offset of anesthesia as well as good intraoperative titratability of the anesthetic. With regard to neuroanesthesia, the reported effects of sevoflurane on cerebral hemodynamics and cerebrospinal fluid dynamics are inconsistent. We used phase-contrast magnetic resonance imaging measurement of systolic cerebrospinal fluid peak velocity (CSFVPeak) to evaluate the effect of sevoflurane on cerebral compliance in healthy individuals. During administration of 0.4 MAC sevoflurane, systolic CSFVPeak in the aqueduct of Sylvius remained unchanged, thereby indicating unaffected cerebral compliance: (CSFVPeak baseline: -3.1 +/- 1.0 cm/s vs. sevoflurane: -3.0 +/- 1.2 cm/s). We conclude that low-dose administration of sevoflurane does not influence cerebral compliance in healthy individuals, but the influence of coexisting intracranial pathology or comedications on cerebral compliance requires further clinical investigation.

Inhaled anesthetics exert metabolically mediated effects on cerebral blood vessels both directly and indirectly. We investigated the effects of a 0.4 minimum alveolar subanesthetic concentration of sevoflurane on regional cerebral blood flow (rCBF), regional cerebral blood volume (rCBV), regional cerebrovascular resistance (rCVR), and regional mean transit time (rMTT) in volunteers by means of contrast-enhanced magnetic resonance imaging perfusion measurement. Sevoflurane increased rCBF by 16% to 55% (control, 55. 03 +/- 0.33 to 148.83 +/- 1.9 mL. 100 g(-1). min(-1); sevoflurane, 71.75 +/- 0.36 to 193.26 +/- 2.14 mL. 100 g(-1). min(-1)) and rCBV by 7% to 39% (control, 4.66 +/- 0.03 to 10.04 +/- 0.12 mL/100 g; sevoflurane, 5.04 +/- 0.03 to 13.6 +/- 0.15 mL/100 g); however, sevoflurane decreased rMTT by 7% to 18% (control, 3.75 +/- 0.04 to 5. 39 +/- 0.04 s; sevoflurane, 3.4 +/- 0.03 to 4.44 +/- 0.03 s) and rCVR by 22% to 36% (control, 0.74 +/- 0.01 to 1.9 +/- 0.2 mm Hg/[mL. 100 g(-1). min(-1)]; sevoflurane, 0.54 +/- 0.01 to 1.41 +/- 0.01 mm Hg/[mL. 100 g(-1). min(-1)]). Interhemispheric differences in rCBF, rCBV, and rCVR were markedly reduced after the administration of sevoflurane. These findings are consistent with the known direct vasodilating effect of sevoflurane. The decrease in rMTT further shows that rCBF increases more than does rCBV. Furthermore, we can show that the observed increase in rCBF during inhalation of sevoflurane is not explained by vasodilation alone.

Remifentanil, a short-acting potent m-opioid agonist proposed for intraoperative analgesia but also for postoperative pain therapy, has not been investigated with regard to the effects of the drug on cerebral capacity in awake humans. We assessed cerebral capacity noninvasively by means of phase-contrast magnetic resonance imaging measurement of systolic cerebrospinal fluid peak velocity in the aqueduct of Sylvius before and during infusion of remifentanil (0.1 mg z kg 21 z min 21 IV) in normocapnic humans. Remifentanil had no significant effect on systolic cerebrospinal fluid peak velocity as compared with baseline (mean 6 sd): baseline, 24.3 6 1.3 cm/s versus remifentanil (0.1 mg z kg 21 z min 21 ): 24.7 6 1.0 cm/s. Small-dose remifentanil (0.1 mg z kg 21 z min 21 ) did not influence cerebral capacity in healthy, awake volunteers free of intracranial pathology. Implications: Knowledge about the influence of remifentanil on cerebral capacity is crucial before routine use of the drug in neuroanesthesia. Thus, we assessed the influence of remifentanil on cerebral capacity noninvasively by means of phase-contrast magnetic resonance imaging measurement of systolic cerebrospinal fluid peak velocity in the aqueduct of Sylvius in humans. (Anesth Analg 2000;90:609 ‐13)

Die kontinuierliche Uberwachung des Herzens und der zentralen, herznahen Gefase mittels transosophagealer Echokardiographie (TEE) ist ein etabliertes Verfahren der erweiterten perioperativen Uberwachung des kardialen Risikopatienten [7,14,18]. Die TEE eroglicht intraoperativ ein kontinuierliches Monitoring der Ventrikelfunktion, eine hochsensitive Uberwachung des Patienten auf Myokardischamien und eine optimierte Beurteilung der links- und rechtsventrikularen Vorlast (Fullungszustand, Volamie). Sowohl intra-als auch postoperativ ist die TEE ein wertvolles Hilfsmittel in der Differentialdiagnostik des hamodynamisch instabilen Patienten [4,22]. Die TEE ist ein semiinvasives, in Notsituationen rasch einsetzbares Verfahren. Die TEE liefert Informationen (anatomische Information, Information uber Blutflusse), die mit keinem alternativen Uberwachungsverfahren zu erhalten sind. Untersuchungen haben gezeigt, dass die TEE im Operationssaal oder auf der Intensivstation bei 30–50% der Patienten neue, die Therapie wesentlich beeinflussende diagnostische Informationen liefert [4,11,18]. Im Folgenden sollen die Grundlagen der TEE und die wichtigsten Einsatzmoglichkeiten fur den Anasthesisten vorgestellt werden.

Contrast‐enhanced magnetic resonance imaging (MRI) measurement of cerebral perfusion is a diagnostic procedure increasingly gaining access to clinical practice not only in spontaneously breathing patients but also in mechanically ventilated patients. Effects of increased mean airway pressure on cerebral perfusion are entirely possible. Therefore, the present study used continuous positive airway pressure (CPAP) (12 cm H2O) to study the effects of increased mean airway pressure on cerebral perfusion in volunteers. CPAP significantly reduced regional cerebral blood flow (rCBF) and regional cerebral blood volume (rCBV) but increased regional mean transit time (rMTT) and regional cerebrovascular resistance (rCVR). Active vasoconstriction (e.g., arterial) and/or passive compression of capillary and/or venous vessel areas are the most likely underlying mechanisms. The number of interhemispheric differences in rCBF, rCBV, rMTT, and rCVR found at baseline rose when mean airway pressure was increased. These results, although obtained in volunteers, should be taken into consideration for the interpretation of contrast‐enhanced MRI perfusion measurements in mechanically ventilated patients with an increased positive airway pressure. Hum. Brain Mapping 11:214–222, 2000. © 2000 Wiley‐Liss, Inc.

Background Cerebrospinal fluid (CSF) outflow to intra- and extracranial subarachnoid spaces caused by arterial inflow to the brain predominantly compensates systolic increases in cerebral blood volume. Phase-contrast magnetic resonance imaging is a new tool for noninvasive assessment of CSF displacement by measuring CSF peak velocity (CSFV(Peak)). The authors tested this new tool in an experimental human model of increased intracranial pressure and reduced cerebral capacity by means of continuous positive airway pressure (CPAP) breathing. Methods The authors investigated systolic CSFV(Peak) in the aqueduct of Sylvius in 11 awake, normocapnic (end-tidal carbon dioxide [ET(CO2)] = 40 mmHg) volunteers without CPAP and at two different CPAP levels (6 and 12 cm H2O) by means of electroencephalography-gated phase-contrast magnetic resonance imaging. Results Administration of 6 cm H2O CPAP did not change systolic CSFV(Peak) (-4.9+/-2.8 cm/s vs. control: -5.1+/-2.7 cm/s), whereas 12 cm H2O CPAP significantly reduced systolic CSFV(Peak) (-4.0+/-1.8 cm/s vs. control: -5.1+/-2.7 cm/s; P < 0.05). Conclusions These findings in awake volunteers show that monitoring CSFV(Peak) in the aqueduct of Sylvius is a sensitive method for detecting even minor impairment of cerebral capacity caused by experimentally induced increases in intracranial pressure.

The present work provides assistance for physicians concerning decision making in clinical borderline situations in the ICU. Based on a structured checklist the two fundamental aspects of any medical decision, the medical indication and the patient's preference are queried in a systematic way. Four possible steps of withholding and/or withdrawing therapy are discussed. Finally, recommendations regarding appropriate documentation of end of life decisions are provided.

sensitizing effect in the cardiac myofilaments.Pleiotropic effects include activation of adenosine triphospha-te–sensitive sarcolemmal K channels of smooth muscle cells(linked to vasodilation) and activation of adenosine triphospha-te–sensitive K channels in cardiovascular mitochondria (in-volved in a cardioprotective effect). The active long-lived me-tabolite OR-1896, also an inodilator

The aim of this study was to investigate the influence of acid-base management (pH stat or alpha stat) on hemodynamics and oxygen metabolism during long-term hypothermia in the pig. Seventeen female pigs were anesthetized, slowly cooled to 28 degrees C with cooling mats and kept at this temperature for 36 h. Thereafter, slow rewarming was performed with inhalation of a 40 degrees C warm air/oxygen mixture and insulation. Eight of the 17 pigs were ventilated according to the pH stat strategy and 9 according to the alpha stat strategy. Both groups were compared 4 times each for hemodynamics and metabolism during cooling, hypothermia and rewarming. The 2 strategies showed no significant difference in cardiac output, heart rate or mean arterial pressure. The only difference in hemodynamics was observed in mean pulmonary artery pressure and pulmonary artery resistance during hypothermia, showing higher values in pH stat animals. As for oxygen metabolism, oxygen consumption during hypothermia was significantly higher in alpha stat animals. Long-term hypothermia with spontaneous circulation revealed significant differences in oxygen metabolism and pulmonary artery pressure as well as resistance between alpha and pH stat acid-base management. These differences may be of importance when using moderate hypothermia in a clinical or experimental setting.

Objectives: We aimed to examine organizational, structural and routine infection control measures provided by European ICUs and staff practices in ventilator-associated pneumonia prevention in relation with current recommendations. Methods: European ICU staffs were invited to complete a web-based 20 closed-item questionnaire. Results: 675 nurses and 886 physicians from 13 countries answered the questionnaire. Median number of respondents per country was 118.0 (64.5-155.5). Availability and organizational aspects of infection control revealed wide variations between countries. Among them, single-patient rooms was the aspect with the lowest availability (median availability 38%), but the largest variation ranging from 15 to 84%. Self-reported median adherence rate to recommendations was 72% (34.5-83.0) with a strong correlation between nurses and physicians responses (r(2) = 0.96; p

OBJECTIVE To examine the glottic function in extubated patients recovering from acute lung injury by simultaneous measurement of airway opening and subglottic airway pressures while patients are breathing at ambient pressure and receiving continuous positive airway pressure by a face mask. DESIGN Descriptive, prospective study. SETTING Intensive care unit at a university hospital. PATIENTS Ten patients who required continuous positive airway pressure of at least 7 cm H2O in order to restore gas exchange after mechanical ventilation for acute lung injury. INTERVENTIONS Spontaneous breathing at ambient airway pressure and with continuous positive airway pressures of 5 and 10 cm H2O via face mask. MEASUREMENTS AND MAIN RESULTS Intratracheal pressure, airway opening pressure, and airflow at the airway opening were measured. Breathing at ambient pressure resulted in significantly higher end-expiratory intratracheal pressure than end-expiratory airway opening pressure (p < .01). No significant differences between end-expiratory intratracheal pressure and end-expiratory airway opening pressure were observed during breathing with continuous positive airway pressures of 5 and 10 cm H2O. A significant end-expiratory airflow at the airway opening (p < .01), observed during ambient pressure breathing, was not detectable while the patient received mask continuous positive airway pressure. The partial pressure of oxygen in the arterial blood (Pao2) increased significantly while patients breathed with 10 cm H2O, but not while patients breathed 5 cm H2O continuous positive airway pressure compared with breathing at ambient pressure (p < .05). CONCLUSIONS Our data imply that patients recovering from acute lung injury create an intratracheal positive end-expiratory pressure by braking the expiratory airflow, probably by glottic narrowing. Despite compensatory glottic narrowing, extubated patients with reduced lung function may benefit from higher levels of continuous positive airway pressure.

UNLABELLED Phase-contrast magnetic resonance imaging measurements of systolic cerebrospinal fluid peak velocity (CSFVPeak) in the aqueduct of Sylvius have been shown to be sensitive enough to detect even minor changes in cerebral compliance. Clinically relevant changes in cerebral compliance can be caused by changes in cerebral blood volume (CBV). Changes in arterial carbon dioxide partial pressure, which correlate well with end-tidal carbon dioxide concentration (ETCO(2)), cause changes in CBV. In this study, we investigated the effect of hypercapnia-induced changes in CBV on systolic CSFVPeak in anesthetized patients (n = 8). Hypercapnia (ETCO(2) = 60 mm Hg) increased systolic CSFVPeak in the aqueduct of Sylvius as compared with normocapnia (ETCO(2) = 40 mm Hg) (hypercapnia: -5.67 +/- 0.74 cm/s versus normocapnia: -3.54 +/- 0.98 cm/s). In addition to the already known decrease in systolic CSFVPeak, changes in cerebral compliance can also prompt an increase in systolic CSFVPeak. IMPLICATIONS Magnetic resonance imaging measurements of systolic cerebrospinal fluid peak velocity (CSFVPeak) in the aqueduct of Sylvius are sensitive enough to detect even minor changes in cerebral compliance. We investigated the effect of hypercapnia-induced changes in cerebral blood volume on systolic CSFVPeak in anesthetized patients. Hypercapnia (end-tidal carbon dioxide concentration = 60 mm Hg) increased systolic CSFVPeak.

OBJECTIVE To examine the effects of continuous positive airway pressure applied via face masks and nose masks on the change in functional residual capacity and gas exchange. DESIGN Descriptive and prospective study. SETTING Intensive care unit of a university hospital. PATIENTS Ten patients with acute lung injury who had required mechanical ventilation. INTERVENTIONS Continuous positive airway pressure at a level of 10 cm H2O applied in random order via face and nose masks. MEASUREMENTS AND MAIN RESULTS Both continuous positive airway pressure methods resulted in an almost identical increase of functional residual capacity. During nasal continuous positive airway pressure, the increase in functional residual capacity was 294 +/- 82 mL. During mask continuous positive airway pressure, the increase in functional residual capacity was 290 +/- 85 mL. PaO2 increased and the alveolar-arterial oxygen tension/alveolar oxygen tension quotient decreased significantly during mask continuous positive airway pressure and nasal continuous positive airway pressure at a level of 10 cm H2O. Two patients showed a periodic change in their breathing patterns; they took a few breaths at an increased lung volume, followed by one deep expiration caused by mouth opening. Change in mask pressure was negligible in these two patients. Using a visual analog scale (10 = highly comfortable; 0 = severely uncomfortable), the patients rated nasal continuous positive airway pressure (8.6 +/- 0.9) significantly more comfortable than mask continuous positive airway pressure (2.6 +/- 0.8). CONCLUSION The major advantages of continuous positive airway pressure (the improvement of functional residual capacity and oxygen transfer) can also be achieved with nasal continuous positive airway pressure in the postextubation period in patients who have been mechanically ventilated for acute lung injury.

Background The authors tested the hypothesis that pressure support ventilation (PSV) provides more effective gas exchange than does unassisted ventilation with continuous positive airway pressure (CPAP) in anesthetized adult patients treated using the laryngeal mask airway. Methods Forty patients were randomized to two equal-sized crossover groups, and data were collected before surgery. In group 1, patients underwent CPAP, PSV, and CPAP in sequence. In group 2, patients underwent PSV, CPAP, and PSV in sequence. PSV comprised positive end expiratory pressure set at 5 cm H2O and inspiratory pressure support set at 5 cm H2O above positive end expiratory pressure. CPAP was set at 5 cm H2O. Each ventilatory mode was maintained for 10 min. The following data were recorded every minute for the last 5 min of each ventilatory mode and the average reading taken: end tidal carbon dioxide, oxygen saturation, expired tidal volume, leak fraction, respiratory rate, noninvasive mean arterial pressure, and heart rate. Results In both groups, PSV showed lower end tidal carbon dioxide (P < 0.001), higher oxygen saturation, (P < 0.001), and higher expired tidal volume (P < 0.001) compared with CPAP. In both groups, PSV had similar leak fraction, respiratory rate, mean arterial pressure, and heart rate compared with CPAP. In group 1, measurements for CPAP were similar before and after PSV. In group 2, measurements for PSV were similar before and after CPAP. Conclusion The authors concluded that PSV provides more effective gas exchange than does unassisted ventilation with CPAP during LMA anesthesia while preserving leak fraction and hemodynamic homeostasis.

In the year 2006 over 1000 liver transplantation (LTX) were performed in Austria, Germany and Switzerland. The feasible association of liver failure with pathologic affections of all other organ systems requires a thorough examination of the potential liver host and a carefully guided anaesthesia. A comprehensive monitoring of the patient and an elaborate therapeutic concept is necessary to meet the peculiar pathophysiologic conditions during LTX. This report describes the anaesthesiological relevant aspects of the LTX and provides suitable therapeutic options.

Survival of hypothermic avalanche victims with cardiac arrest is rare. This report describes full recovery of a 29-year-old backcountry skier completely buried for 100 min at 3.0m (9.8 ft) depth. On extrication he was unconscious, but breathing spontaneously into an air pocket; core body temperature measured 22.0 degrees C (71.6 degrees F). He was intubated and ventilated on site. Ventricular fibrillation commenced during helicopter transportation, whereby chest compression was lacking for 15 min. At the nearest hospital continuous cardiopulmonary resuscitation was initiated, but defibrillation failed. Tympanic core body temperature measurement confirmed life-threatening hypothermia of 21.7 degrees C (71.1 degrees F) and serum K(+) was 4.3 mmol/l, necessitating transferral to a hospital with cardiopulmonary bypass facilities. Defibrillation finally succeeded following re-warming, by femoral veno-arterial bypass, to 34.5 degrees C (94.1 degrees F). Total duration of cardiac arrest was 150 min. The patient developed pulmonary oedema, treated by extracorporeal membrane oxygenation, but progressed well and was discharged from hospital on day 17, fit to resume professional and social activities. Follow-up cerebral magnetic resonance imaging 2 years after avalanche burial demonstrated only minimal changes attributable to unrelated, prior cranial trauma. Extensive neurological and psychological investigations gave excellent results. This report confirms previous literature that an air pocket with patent airways is essential for survival of a completely buried avalanche victim after 35 min and endorses the recommended management strategies of the International Commission for Mountain Emergency Medicine ICAR MEDCOM. In particular, all hypothermic victims extricated with an air pocket and free airways must be treated optimistically, even despite prolonged cardiac arrest. This remarkable case documents the fastest drop in core temperature ever recorded during snow burial, namely 9.0 degrees C (16.2 degrees F)/h, and the second-lowest reversible core temperature in avalanche literature.

Mean cerebral blood flow velocity (CBFVMCA) and mean cerebral perfusion pressure (CPP) were investigated in five patients undergoing placement of an implantable cardioverter/defibrillator during 30 periods of induced pulseless ventricular tachycardia (VT) or induced ventricular fibrillation (VF) with a duration from 4 seconds to a maximum of 47 seconds. During VT (n=6) CBFVMCA decreased from 42 cm/sec (range: 32-60) to 20 cm/sec (range: 17-28) and during VF (n=24) it decreased from 44 cm/sec (range: 28-75) to 13 cm/sec (range: 10-15). CPP decreased from 66 mm Hg (range: 60-72) to 30 mm Hg (range: 27-38) during VT and from 63 mm Hg (range: 58-85) to 15 mm Hg (range: 8-25) during VF. Regardless of the type of underlying cardiac rhythm, transcranial Doppler ultrasonography revealed a constant forward blood flow in the middle cerebral artery during the early phase of induced VT or VF.