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The neutron activation technique is a well established method to measure neutron capture cross sections relevant for the s-process. The 7Li(p,n) reaction at Ep = 1912 keV is often used as a neutron source since the energy distribution of the emitted neutrons closely resembles a Maxwell-Boltzmann spectrum of kBT = 25 keV, mimicking the 22Ne(α,n) phase in TP-AGB stars. The weak s-process, which takes place in massive stars, can reach energies up to kBT = 90 keV. Neutron spectra corresponding to a Maxwell-Boltzmann distribution with kBT > 25 keV cannot be produced by the 7Li(p,n) reaction directly. We developed a method to obtain quasi-Maxwellian neutron capture cross sections over a wide energy range by combining a set of spectrum average cross sections measured at six different proton energies and distances between the lithium target and the sample. The measured spectrum averaged cross section can be used to calculate the Maxwellian-Averaged cross-section (MACS) from kBT = 25 keV to kBT = 90 keV. Over the last two years neutron capture cross sections on over 20 isotopes have been measured at Goethe University Frankfurt using this methodology. An overview of the current experimental method, challenges during data analysis and the first results are presented.

The slow neutron capture process produces heavy elements in different stellar sites at different temperatures. Neutron capture cross sections for stellar temperatures between kBT = 5 keV and kBT = 100 keV are crucial for a quantitative understanding of the s-process abundance distribution. Over the last decade activation measurements were performed at the Goethe University Frankfurt to study cross sections at a temperature of kBT = 25 keV. We developed a new method to measure neutron capture cross sections at kBT = 6 keV.

We measured the Coulomb dissociation of 16O into 4He and 12C within the FAIR Phase-0 program at GSI Helmholtzzentrum für Schwerionenforschung Darmstadt, Germany. From this we will extract the photon dissociation cross section 16O(α,γ)12C, which is the time reversed reaction to 12C(α,γ)16O. With this indirect method, we aim to improve on the accuracy of the experimental data at lower energies than measured so far. The expected low cross section for the Coulomb dissociation reaction and close magnetic rigidity of beam and fragments demand a high precision measurement. Hence, new detector systems were built and radical changes to the R3B setup were necessary to cope with the high-intensity 16O beam. All tracking detectors were designed to let the unreacted 16O ions pass, while detecting the 12C and 4He.

The neutron activation method is well-suited to investigate neutron-capture cross sections relevant for the main s-process component. Neutrons can be produced via the 7Li(p,n) reaction with proton energies of 1912 keV at e.g. Van de Graaff accelerators, which results in a quasi-Maxwellian spectrum of neutrons corresponding to a temperature of kBT = 25 keV. However, the weak s-process takes place in massive stars at temperatures between 25 and 90 keV. Simulations using the PINO code [2] suggest that a Maxwellian spectrum for higher energies, e.g. kBT = 90 keV, can be approximated by a linear combination of different neutron spectra. To validate the PINO code at proton energies Ep ≠ 1912 keV, neutron time-of-flight measurements were carried out at the PTB Ion Accelerator Facility (PIAF) at the Physikalisch-Technische Bundesanstalt in Braunschweig, Germany.

The determination of astrophysically relevant neutron-induced cross sections is particularly difficult when the involved isotopes are radioactive or the cross sections are very small. Activation experiments at reactors offer the possibility to overcome these limitations with high neutron fluxes. The flux determination is typically based on the activation of two monitors with known cross sections to separate the different flux components. The usually applied cadmium difference method allows a distinction between the thermal and the epithermal part. By a combination of two linear functions representing both monitors the neutron flux components can be determined. However, if more than two monitors are used, the linear system of equations is overdetermined, which allows the identification of a probability distribution. In this proceeding, the feasibility and relevance of this method is demonstrated.

About 50% of the elements heavier than iron are produced during the slow neutron capture process. This process occurs in different stellar sites at various energies. To understand the ongoing nucleosynthesis, the probability of a neutron capture for different temperatures and therefore for different stellar sites is essential. Activation experiments using the 7Li(p,n) reaction as neutron source were performed. At a temperature of kBT = 25 keV the cross sections were determined for 27Al, 37Cl and 41K. A new method was developed to perform activation experiments at even lower temperatures. For a proof of principle, the cross section for 64Ni was measured at kBT = 25 keV as well as for kBT = 6 keV. To study the impact of isomeric states at higher energies, activations of 181Ta were performed using two different proton energies.

Background: Early goal-directed hemodynamic optimization has become a cornerstone of sepsis therapy. One major defined goal is to achieve adequate central venous oxygen saturation (SO(2)). This study aimed to investigate the correlation between central venous SO(2) and frontal cerebral near-infrared spectroscopy (NIRS) measurement in patients with severe sepsis and septic shock. The NIRS method provides non-invasive measurement of regional oxygen saturation (rSO(2)) in tissues approximately 2 cm below the optical NIRS sensors which depends on arterial, capillary and venous blood. Thus this system gives site-specific real-time data about the balance of oxygen supply and demand.Methods: This was a secondary analysis from a prospective study of surgical intensive care (ICU) patients in the early phase of severe sepsis or septic shock. Bilateral cerebral rSO(2), central venous SO(2), arterial oxygen saturation (S(a)O(2)) and other surrogate parameters of oxygen supply, such as hemoglobin, partial pressure of oxygen and oxygen content in arterial blood were recorded.Results: A total of 16 ICU patients (4 women, median age 65.5 years) were included in the study. As sepsis focus an intra-abdominal infection was detected in 62.5 % of patients, severe pneumonia was determined in 31.3 % and skin and soft tissue infections were recognized in 12.5 %. At study inclusion 50 % of patients had septic shock, the median sequential organ failure assessment (SOFA) score was 10.2 (interquartile range 5.25-8.75) and the median acute physiology and chronic health evaluation II (APACHE II) score was 26 (range 23.25-29.75). Mortality at day 28 was 37.5 %. Minimum rSO(2) (median 58) and right-sided rSO(2) (median 58) values showed a significant correlation in the analysis of receiver operating characteristics (area under the curve 0.844, p= 0.045). A central venous SO(2)< 70 % was indicated by rSO(2)< 56.5 with sensitivity and specificity of 75 % and 100 %, respectively.Conclusions: Cerebral NIRS could provide a fast and easily available side effect-free monitoring that could be used in addition to established procedures for goal-directed treatment in the early phase of sepsis. Further studies should be made in a larger population to verify the correlation found and to investigate the impact of NIRS-directed resuscitation treatment in early sepsis. [ABSTRACT FROM AUTHOR]

Intensive care medicine plays an important role in the medical care of patients as well as the economic success of hospitals. Knowledge and implementation of recent relevant scientific evidence are prerequisites for high quality care in intensive care medicine. The aim of this review is to present an overview of the most important publications in intensive care medicine published in 2010 and the first half of the year 2011 and to comment on their attributable clinical relevance for intensive care practitioners. In 2010 and up to June 2011 many studies with high patient numbers have been published. The main topics were the treatment of respiratory failure, sepsis and investigations to improve analgosedation. [ABSTRACT FROM AUTHOR]

Scoring systems are used in all diagnostic areas of medicine. Several parameters are evaluated and rated with points according to their value in order to simplify a complex clinical situation with a score. The application ranges from the classification of disease severity through determining the number of staff for the intensive care unit (ICU) to the evaluation of new therapies under study conditions. Since the introduction of scoring systems in the 1980's a variety of different score models has been developed. The scoring systems that are employed in intensive care and are discussed in this article can be categorized into prognostic scores, expenses scores and disease-specific scores. Since the introduction of compulsory recording of two scoring systems for accounting in the German diagnosis-related groups (DRG) system, these tools have gained more importance for all intensive care physicians. Problems remain in the valid calculation of scores and interpretation of the results. [ABSTRACT FROM AUTHOR]

Background: This study was a pre-planned country-specific secondary analysis of results in Germany from a multinational multicenter observational study to retrospectively evaluate clinical outcomes with caspofungin in patients with probable and proven invasive fungal infection following solid organ transplantation (SOT).Methods: Data were retrospectively collected on a single episode of invasive fungal infection (IFI) in patients who had a SOT between January 2004 and June 2007. Effectiveness was reported as the proportion of patients who received at least five doses of caspofungin with a favorable (complete or partial) response. Safety was assessed for patients who received at least one dose of caspofungin. Descriptive statistics were employed for all evaluations.Results: A total of 41 SOT patients (27 male, 14 female; median age 56 years, median APACHE II score at start of caspofungin therapy 23) were enrolled from 5 sites in Germany. Organs transplanted were mainly heart (51%) and liver (46%). Prevalent risk factors for IFI at baseline were use of central venous catheter (37 out of 41 patients, 90%), steroid use (37 out of 41 patients, 90%), recent stay in intensive care (36 out of 41 patients, 88%),and duration of SOT procedure >5 hours (21 out of 41 patients, 51%). Candidiasis was diagnosed in 34 patients (83%) and aspergillosis in 10 patients (24%). The lungs were the most common site of IFI (21 out of 41, 51%). Caspofungin as monotherapy was received by 28 patients (68%); 6 patients (15%) received caspofungin as salvage therapy for IFI, in most cases because they were refractory to prior antifungal drugs. Immunosuppressants were administered with caspofungin in 39 out of 41 patients (95%). In subjects with at least 5 doses of caspofungin (modified intention to treat population) the favorable response rate at the end of caspofungin therapy was 88% overall, 29 out of 33 patients; 95% confidence interval (95%-CI) 72-97%), 86% (19 out of 22 patients) with monotherapy and 91% (10 out of 11 patients) with combination therapy. No (serious) adverse events or drug interactions related to treatment with caspofungin were reported. The overall survival rate was 79% (26 out of 33 patients; 95%-CI 61-91%) at 7 days after completion of caspofungin treatment.Conclusion: Caspofungin was found to be an effective treatment of probable and proven invasive fungal infections in patients following SOT in Germany. [ABSTRACT FROM AUTHOR]

Critical care medicine plays an important role for the medical and economic success of hospitals. Knowledge and implementation of recent relevant studies are prerequisites for high quality intensive care medicine. The aim of the present manuscript is to present an overview of the most important publications in intensive care medicine in 2009 and comment on their clinical relevance. It has to be recognized that the cited studies are chosen according to the view of the authors. In 2009 many large randomized studies with high patient numbers were published. Main topics in 2009 were the therapy of lung failure, analgosedation and sepsis therapy. New trends are bedside echocardiography and telemedicine. Unfortunately, a magic bullet has not been identified last year. The focus is still on team education and guideline-assisted therapy. [ABSTRACT FROM AUTHOR]

Background: Painful procedures on children and adolescents often have to be performed with the aid of analgesia and sedation in order to prevent pain and emotional distress. Moreover, many procedures can be performed more rapidly and more effectively in a relaxed patient. Because the combination of analgesia and sedation can cause serious or even life-threatening complications, it must be accompanied by the same safety precautions as a general anesthetic. Methods: Selective review of the literature. Results: A high level of safety can be achieved by adherence to the published guidelines of the societies for anesthesiology and pediatrics. The depth of sedation during procedures performed under combined analgesia and sedation is often equivalent to that resulting from general anesthesia. Therefore, in order to avoid serious complications, combined analgesia and sedation should only be administered by physicians trained in pediatric anesthesia or pediatric critical care. This is particularly so when propofol is used, because it has a narrow therapeutic range and can cause cardiorespiratory respiratory problems without warning. As long as the appropriate safety precautions are followed, non-anesthesiologists can also administer propofol in combination with an analgesic, such as ketamine, to children and adolescents. Conclusion: In children and adolescents, the combination of analgesia and sedation can prevent the emotional trauma that would result from a painful procedure, while often enhancing the quality of the procedure itself. This method should be considered a variant of general anesthesia. Accordingly, any non-anesthesiologist employing this method must be as well versed as an anesthesiologist in the management of its specific side effects and complications. [ABSTRACT FROM AUTHOR]

Fungal infections are of great relevance in surgical intensive care and Candida species represent the predominant part of fungal pathogens. Invasive aspergillosis is also relevant especially in patients with chronic pulmonary diseases. It is crucial for therapy success to begin adequate antifungal treatment at an early stage of the disease. Risk stratification of individual patient symptoms is essential for therapy timing. In case of suspected or proven candida infection, fluconazole is the agent of choice when the patient is clinically stable and no azoles have been administrated in advance and the local epidemiology makes azol resistance unlikely. For clinically instable patients with organ dysfunction the echinocandins serve as primary therapy because of their broad spectrum and reasonable safety profile. Due to a relevant proportion of azole resistant Candida species, susceptibility testing should be done routinely. Depending on the species detected de-escalating to an azole is feasible if organ dysfunctions have resolved. An invasive aspergillosis is primarily treated with voriconazole. [ABSTRACT FROM AUTHOR]

Traumatic injury of the aorta can be a fatal complication of blunt thoracic trauma and if it is survived and diagnosed, surgery will be necessary. A prerequisite is a prompt imaging diagnosis of the injury in order to plan an optimal therapeutic procedure for the patient, depending on the severity of the injury. Digital angiography has now been replaced by non-invasive methods, such as computer tomography (CT) or transesophageal echocardiography (TEE). Using TEE it is possible to carry out a staging of the injury and this classification together with the corresponding clinical symptoms determines the therapeutic treatment regime. In many cases a staged treatment is standard procedure. In addition to the establishment of an adequate blood pressure (for prophylaxis of the open rupture), monitoring during the course of treatment may be necessary. The main advantage of TEE is that the examination of these mostly multiple traumatised patients can be carried out at the bedside. This review describes the use of TEE as a diagnostic tool in the early phase and for continuous monitoring of an initially conservative treatment regime. [ABSTRACT FROM AUTHOR]

Neutron total cross sections are an important source of experimental data in the evaluation of neutron-induced cross sections. The sum of all neutron-induced reaction cross sections can be determined with a precision of a few per cent in a relative measurement. The neutron spectrum of the photoneutron source nELBE extends in the fast region from about 100 keV to 10 MeV and has favourable conditions for transmission measurements due to the low instantaneous flux of neutrons and low gamma-flash background. Several materials of interest (in part included in the CIELO evaluation or on the HPRL of OECD/NEA) have been investigated: 197Au [1, 2], natFe [2], natW [2], 238U, natPt, 4He, natO, natNe, natXe. For gaseous targets high pressure gas cells with flat end-caps have been built that hold up to 200 bar pressure. The experimental setup will be presented including results from several transmission experiments and the data analysis leading to the total cross sections will be discussed.

Activations with neutrons in the keV energy range were routinely performed at the Karlsruhe Institute of Technology (KIT) in Germany in order to simulate stellar conditions for neutron-capture cross sections. A quasi-Maxwell-Boltzmann neutron spectrum of kT = 25 keV, being of interest for the astrophysical s-process, was produced by the 7Li(p,n) reaction utilizing a 1912 keV proton beam at the Karlsruhe Van de Graaff accelerator. Activated samples resulting in long-lived nuclear reaction products with half-lives in the order of yr 100 Myr were analyzed by Accelerator Mass Spectrometry (AMS). Comparison of the obtained reaction cross sections to literature data from previous Time-of-Flight (ToF) measurements showed that the selected AMS data are systematically lower than the ToF data. To investigate this discrepancy, 54Fe(n,γ)55Fe and 35Cl(n,γ)36Cl reaction cross sections were newly measured at the Frankfurt Neutron Source (FRANZ) in Germany. To complement the existing data, an additional neutron activation of 54Fe and 35Cl at a proton energy of 2 MeV was performed. The results will give implications for the stellar environment at kT = 90 keV, reaching the not yet experimentally explored high-energy s-process range. AMS measurements of the activated samples are scheduled.

Neutron capture and β− -decay are competing branches of the s-process nucleosynthesis path at 85Kr [1], which makes it an important branching point. The knowledge of its neutron capture cross section is therefore essential to constrain stellar models of nucleosynthesis. Despite its importance for different fields, no direct measurement of the cross section of 85Kr in the keV-regime has been performed. The currently reported uncertainties are still in the order of 50% [2, 3]. Neutron capture cross section measurements on a 4% enriched 85Kr gas enclosed in a stainless steel cylinder were performed at Los Alamos National Laboratory (LANL) using the Detector for Advanced Neutron Capture Experiments (DANCE). 85Kr is radioactive isotope with a half life of 10.8 years. As this was a low-enrichment sample, the main contaminants, the stable krypton isotopes 83Kr and 86Kr, were also investigated. The material was highly enriched and contained in pressurized stainless steel spheres.

We measured the neutron capture cross sections of 69Ga and 71Ga for a quasi-stellar spectrum at kBT = 25 keV and a spectrum with a peak energy at 90 keV by the activation technique at the Joint Research Centre (JRC) in Geel, Belgium. Protons were provided by an electrostatic Van de Graaff accelerator to produce neutrons via the reaction 7Li(p,n). The produced activity was measured via the γ emission of the product nuclei by high-purity germanium detectors. We present preliminary results.

The huge neutron fluxes offer the possibility to use research reactors to produce isotopes of interest, which can be investigated afterwards. An example is the half-lives of long-lived isotopes like 129I. A direct usage of reactor neutrons in the astrophysical energy regime is only possible, if the corresponding ions are not at rest in the laboratory frame. The combination of an ion storage ring with a reactor and a neutron guide could open the path to direct measurements of neutron-induced cross sections on short-lived radioactive isotopes in the astrophysically interesting energy regime.

Neutron capture cross sections of unstable isotopes are important for neutron-induced nucleosynthesis as well as for technological applications. A combination of a radioactive beam facility, an ion storage ring and a high flux reactor would allow a direct measurement of neutron induced reactions over a wide energy range on isotopes with half lives down to minutes. The idea is to measure neutron-induced reactions on radioactive ions in inverse kinematics. This means, the radioactive ions will pass through a neutron target. In order to efficiently use the rare nuclides as well as to enhance the luminosity, the exotic nuclides can be stored in an ion storage ring. The neutron target can be the core of a research reactor, where one of the central fuel elements is replaced by the evacuated beam pipe of the storage ring. Using particle detectors and Schottky spectroscopy, most of the important neutron-induced reactions, such as (n,γ), (n,p), (n,α), (n,2n), or (n,f), could be investigated.

Abstract Background Although a device is needed to continuously measure blood glucose levels within an intensive care setting, and several large-scale prospective studies have shown that patients might benefit from intensive insulin, potassium, or glucose therapy during intensive care, no devices are currently available to continuously assess blood glucose levels in critically ill patients. We conceived the study described here to evaluate the clinical use of the Continuous Glucose Monitor (CGM) performed via a central vein, and to determine the impact of phenomena, such as drift and shift, on the agreement between the CGM and a RAPIDLab® 1265 blood gas analyser (BGA). Methods/design In the CONTinuous ASSessment of blood GLUcose (CONTASSGLU) study, up to 130 patients under intensive care will be fitted with the CGM, an ex vivo device that continuously measures blood glucose and lactate levels. Readings from the device taken 8 h after initial placement and calibration will be compared with values measured by a BGA. For this study, we chose the BGA as it is an established standard point-of-care device, instead of the devices used in certified central laboratories. Nevertheless, we will also independently compare the results from the point-of-care BGA with those determined by a central laboratory-based device. Blood samples will be collected from each patient from the same site in which the CGM will measure blood glucose. Consequently, each participant will serve as their own control, and no randomisation is necessary. The 95% limits of agreement and the corresponding confidence intervals will be calculated and compared with a prespecified clinically acceptable relative difference of 20%. Discussion Several attempts have been made to develop a device to continuously measure blood glucose levels within an intensive care setting or to use the devices that were originally designed for diabetes management, as several of these devices are already available. However, none of these devices were successful in intensive care settings. CONTASSGLU may well bridge this gap by confirming the ability of the CGM to continuously measure blood glucose levels in intensive care settings. Trial registration ClinicalTrials.gov NCT01580176

Abstract Background Intraoperative haemorrhage is a known predictor for perioperative outcome of patients undergoing hepatic resection. While anaesthesiological lowering of central venous pressure (CVP) by fluid restriction is known to reduce bleeding during transection of the hepatic parenchyma its potential side effects remain poorly investigated. In theory it may have negative effects on kidney function and tissue perfusion and bears the risk to result in severe haemodynamic instability in case of profound intraoperative blood loss. The present randomised controlled trial evaluates efficacy and safety of infrahepatic inferior vena cava (IVC) clamping as an alternative surgical technique to reduce CVP during hepatic resection. Methods/Design The proposed IVC CLAMP trial is a single-centre randomised controlled trial with a two-group parallel design. Patients and outcome-assessors are blinded for the treatment intervention. Patients undergoing elective hepatic resection due to any reason are enrolled in IVC CLAMP. All patients admitted to the Department of General-, Visceral-, and Transplant Surgery, University of Heidelberg for elective hepatic resection are consecutively screened for eligibility and written informed consent is obtained on the day before surgery. The primary objective of this trial is to assess and compare the amount of blood loss during hepatic resection in patients receiving surgical CVP reduction by clamping of the IVC as compared to anaesthesiological CVP without infrahepatic IVC clamping reduction. In addition to blood loss a set of general as well as surgical variables are analysed. Discussion This is a randomised controlled patient and observer blinded two-group parallel trial designed to assess efficacy and safety of infrahepatic IVC clamping during elective hepatectomy. Trial registration ClinicalTrials NCT00732979

Abstract Background Major surgical procedures facilitate systemic endotoxinemia and formation of free radicals with subsequent inflammatory changes that can influence the postoperative course. Experimental data suggest that preoperative supraphysiological doses of melatonin, a potent immuno-modulator and antioxidant, would decrease postoperative infectious and non-infectious complications induced by major abdominal surgery. Methods/Design A randomized controlled double blind single center clinical trial with two study arms comprising a total of 40 patients has been designed to assess the effects of a single preoperative dose of melatonin before major liver resection. Primary endpoints include the determination of safety and tolerance of the regimen as well as clinical parameters reflecting pathophysiological functions of the liver. Furthermore, data on clinical outcome (infectious and non-infectious complications) will be collected as secondary endpoints to allow a power calculation for a randomized clinical trial aiming at clinical efficacy. Discussion Based on experimental data, this ongoing clinical trial represents an advanced element of the research chain from bench to bedside in order to reach the highest level of evidence-based clinical facts to determine if melatonin can improve the general outcome after liver resection. Trial Registration EudraCT200600530815

Abstract Background Interactions between mononuclear cells and activated pancreatic myofibroblasts (pancreatic stellate cells; PSC) may contribute to inflammation and fibrosis in chronic pancreatitis (CP). Methods Markers of fibrosis and inflammation were concomitantly analysed by immunohistochemistry in chronic pancreatitis tissues. In vitro, PSC were stimulated with TNFalpha and LPS. Primary human blood mononuclear cells (PBMC) and PSC were cocultured, followed by analysis of cytokines and extracellular matrix (ECM) proteins. PBMC were derived from healthy donors and CP and septic shock patients. Results In areas of mononuclear cell infiltration in chronic pancreatitis tissues, there was decreased immunoreactivity for collagen1 and fibronectin, in contrast to areas with sparse mononuclear cells, although PSC were detectable in both areas. LPS and TNFalpha induced collagen1 and fibronectin levels as well as the matrix degradation enzyme MMP-1. Coculture experiments with PSC and PBMC revealed increased fibronectin secretion induced by PBMC. In addition, donor and CP PBMC significantly induced an increase in IL-6, MCP-1 and TGFbeta levels under coculture conditions. Determination of the source of cytokines and ECM proteins by mRNA expression analysis confirmed PSC as major contributors of ECM production. The increase in cytokine expression was PBMC- and also PSC-derived. Conclusion Mononuclear cells modulate the activity of pancreatic stellate cells, which may in turn promote fibrosis and inflammation.

Background: Intraoperative haemorrhage is a known predictor for perioperative outcome of patients undergoing hepatic resection. While anaesthesiological lowering of central venous pressure (CVP) by fluid restriction is known to reduce bleeding during transection of the hepatic parenchyma its potential side effects remain poorly investigated. In theory it may have negative effects on kidney function and tissue perfusion and bears the risk to result in severe haemodynamic instability in case of profound intraoperative blood loss. The present randomised controlled trial evaluates efficacy and safety of infrahepatic inferior vena cava (IVC) clamping as an alternative surgical technique to reduce CVP during hepatic resection.Methods/design: The proposed IVC CLAMP trial is a single-centre randomised controlled trial with a two-group parallel design. Patients and outcome-assessors are blinded for the treatment intervention. Patients undergoing elective hepatic resection due to any reason are enrolled in IVC CLAMP. All patients admitted to the Department of General-, Visceral-, and Transplant Surgery, University of Heidelberg for elective hepatic resection are consecutively screened for eligibility and written informed consent is obtained on the day before surgery. The primary objective of this trial is to assess and compare the amount of blood loss during hepatic resection in patients receiving surgical CVP reduction by clamping of the IVC as compared to anaesthesiological CVP without infrahepatic IVC clamping reduction. In addition to blood loss a set of general as well as surgical variables are analysed.Discussion: This is a randomised controlled patient and observer blinded two-group parallel trial designed to assess efficacy and safety of infrahepatic IVC clamping during elective hepatectomy. [ABSTRACT FROM AUTHOR]

Background: Pulmonary intravascular thrombus formation has been widely observed in patients with respiratory failure, for example, in patients with SARS-CoV-2 infection (COVID-19). The aim of this study was to evaluate the efficacy/safety of alteplase thrombolysis in COVID-19 severe hypoxemic respiratory failure. In this multicenter, open-label study, patients were randomized to receive alteplase (low- or high-dose) over 5 days plus standard of care (SOC), or SOC alone. The primary endpoint was time to clinical improvement (≥ 2-point decrease on WHO Clinical Progression Scale, or hospital discharge) up to Day 28. Secondary endpoints included all-cause mortality at Day 28, treatment failure at Day 28 and change in arterial oxygen partial pressure/fractional inspired oxygen (PaO 2 /FiO 2 ) ratio at Day 6 versus baseline., Results: Sixty-nine patients were randomized to alteplase (low- or high-dose) and 35 to SOC; 65% were on high-flow oxygen or non-invasive ventilation at baseline. Median time to clinical improvement was 25 days in the alteplase group and > 28 days (median not reached) in the SOC group. All-cause mortality was 8/69 (12%) versus 10/35 (29%) in the alteplase versus SOC groups, respectively (unadjusted risk difference [RD], - 17% [95% confidence interval (CI) - 34 to 0], p = 0.047; adjusted RD, - 16% [95% CI - 31 to 1], p = 0.058). The PaO 2 /FiO 2 ratio (mean [standard deviation]) increased by + 30 (84) mmHg in the alteplase group and decreased by - 12 (59) mmHg in the SOC group (adjusted mean difference vs. SOC, p = 0.052). Differences were greater in patients receiving high-dose alteplase, and in those not receiving invasive ventilation. Eighteen patients (26.1%) in the alteplase group discontinued treatment due to adverse events. Major bleeding was more frequent with alteplase than with SOC (9 vs. 0 patients); no bleeding was fatal. The study closed early due to insufficient patient recruitment., Conclusion: Alteplase was not associated with faster clinical recovery from COVID-19 severe hypoxemic respiratory failure. A numerical difference in survival and PaO 2 /FiO 2 ratio was observed, particularly in patients not receiving invasive ventilation. These exploratory findings merit further investigation in larger patient cohorts that are adequately powered to confirm the hypotheses generated in this study regarding the impact of alteplase on treatment outcomes. Trial registration ClinicalTrials.gov: NCT04640194 (November 23, 2020); https://clinicaltrials.gov/study/NCT04640194 (early discontinuation due to insufficient patient recruitment)., (© 2024. The Author(s).)

This prospective, observational study evaluated Hyperspectral Imaging (HSI) to assess the effects of cardiac surgery and cardiopulmonary bypass (CPB) on microcirculation. 40 Patients with severe aortic stenosis were enrolled. 20 patients underwent transapical/transaxillary/transaortic aortic valve replacement (TAVR), 20 underwent an open surgical approach with CPB (SAVR). HSI was used to determine tissue oxygenation (StO 2 and NIR), hemoglobin (THI) and water content (TWI) at the palm before/after surgery (T1/T2), and on the third postoperative day (T3). TAVR patients showed no significant changes of microcirculatory parameters during surgery. TWI significantly increased until T3. SAVR patients showed an increase of TWI and a decrease of THI, while StO 2 and NIR remained unchanged at T2. In SAVR patients, StO 2 and NIR correlated negatively with the duration of CPB and StO 2 correlated with intraoperative urine output at T2. HSI was able to detect microcirculatory changes during cardiac surgery. CPB duration seemed to affect tissue oxygenation. Clinical trial registration: (German Clinical Trial Register): DRKS00024765., (© 2024. The Author(s).)

Integrity of epithelial and endothelial cell barriers is of critical importance for health, barrier disruption is a hallmark of numerous diseases, of which many are driven by carbonyl stressors such as methylglyoxal (MG). Carnosine and anserine exert some MG-quenching activity, but the impact of these and of other histidine containing dipeptides on cell barrier integrity has not been explored in detail. In human proximal tubular (HK-2) and umbilical vein endothelial (HUVEC) cells, exposure to 200 µM MG decreased transepithelial resistance (TER), i.e. increased ionic permeability and permeability for 4-, 10- and 70-kDa dextran, membrane zonula occludens (ZO-1) abundance was reduced, methylglyoxal 5-hydro-5-methylimidazolones (MG-H1) formation was increased. Carnosine, balenine (ß-ala-1methyl-histidine) and anserine (ß-ala-3-methyl-histidine) ameliorated MG-induced reduction of TER in both cell types. Incubation with histidine, 1-/3-methylhistidine, but not with ß-alanine alone, restored TER, although to a lower extent than the corresponding dipeptides. Carnosine and anserine normalized transport and membrane ZO-1 abundance. Aminoguanidine, a well-described MG-quencher, did not mitigate MG-induced loss of TER. Our results show that the effects of the dipeptides on epithelial and endothelial resistance and junction function depend on the methylation status of histidine and are not exclusively explained by their quenching activity., (© 2024. The Author(s).)

Background: Hepatic chemosaturation for inoperable liver tumors is a palliative treatment option with a beneficial effect on survival. However, the procedure regularly leads to circulatory failure during the filtration phase, and hemodynamic management is challenging. Our study aimed to compare two different strategies for hemodynamic management during chemosaturation to develop hypotheses for improving patient care and reducing peri-interventional morbidity. Methods: We conducted a single-center retrospective cohort study including 66 procedures of chemosaturation between May 2016 and March 2024. Procedures were divided into two groups: group 1 was managed with norepinephrine as the only vasopressor and liberal use of hydroxyethyl starch (HES). Group 2 was managed with norepinephrine and vasopressin and the preferred use of balanced crystalloids. We compared these two groups with respect to hemodynamic parameters, laboratory values, and post-interventional complications. Results: The heart rate was highest and the mean arterial pressure (MAP) was lowest during the filtration phase in both groups ( p = 0.868, p = 0.270). The vasoactive inotropic score (VIS) was significantly higher in group 2 during the filtration phase (31.5 vs. 89, p < 0.001). Group 1 received significantly more HES overall (1000 mL vs. 0 mL, p < 0.001). Lactate levels at admission to the ICU were higher in group 1 (22.9 vs. 14.45 mg/dL, p = 0.041). Platelet counts were lower in group 2 from directly after chemosaturation through day 2 ( p = 0.022, p = 0.001, p = 0.032). The INR differed significantly directly after chemosaturation (1.13 vs. 1.26, p = 0.015). Overall, group 1 received significantly more blood products peri-interventionally. There were two bleedings and one ischemic stroke in the overall cohort. There was no peri-interventional mortality. Conclusions: Advanced hemodynamic management ensures low peri-interventional mortality and morbidity. High-dose vasopressors, including vasopressin and the preferred use of balanced crystalloids, are sufficient to stabilize circulatory function during chemosaturation.