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Drylands cover approximately 40% of the Earth’s land surface and are home to over a quarter of the global population. Despite the deficit of surface water, rare but strong precipitation events are the fundamental driver for geomorphic activity in arid regions. A quantification of the frequency and magnitude of episodic river discharge is essential for a robust characterization of flood hazards and, thus, better understanding of the poorly studied hydromorphodynamics in deserts. However, observation data from gauges are sparsely distributed and, if existent, often do not cover a sufficiently long seamless time series or feature extensive gaps. This applies, for instance, to the remote Northwest Namibia, where more than a dozen ephemeral rivers drain the Kunene Highlands towards the Skeleton Coast, yet daily river flow data for a period of several decades is only available from the Hoanib.Hence, we propose a workflow based on the Landsat multispectral satellite imagery archive to detect flood events and their spatial impact since 1984 in a high resolution (30 m) for the entire Kunene Region (~144 km²). To cater for the limitations related to a revisit time of 16 days and potential impracticality of scenes due to cloud cover, we calculated spectral indices allowing for the detection of both inundated areas during flooding (e.g., Normalized Difference Water Index) and effects sustained after flood recession (e.g., Tasseled Cap Wetness to detect increased soil moisture). The large remote sensing dataset is processed via cloud computing using the Google Earth Engine. As a novel approach, we try to implement a frequency analysis directly in the Google Earth Engine environment after attributing the spectral imprints of floods to their magnitudes. For this purpose, a statistical relationship is developed between the daily record of the gauging station at the Hoanib and the spatiotemporal multispectral surface characteristics along the river course and floodplains. By transferring this relationship to the other ephemeral streams, spatially highly resolved recurrence intervals for areas affected by floods of different magnitudes can be derived for the entire Kunene Region.

The contribution of veno-venous (VV) extracorporeal membrane oxygenation (ECMO) to systemic oxygen delivery is determined by the ratio of total extracorporeal blood flow (Q˙EC) to cardiac output (Q˙). Thermodilution-based measurements of Q˙ may be compromised by blood recirculating through the ECMO (recirculation fraction; Rf). We measured the effects of Q˙EC and Rf on classic thermodilution-based measurements of Q˙ in six anesthetized pigs. An ultrasound flow probe measured total aortic blood flow (Q˙A0) at the aortic root. Rf was quantified with the ultrasound dilution technique. Q˙EC was set to 0-125% of Q˙A0 and Q˙ was measured using a pulmonary artery catheter (PAC) in healthy and lung injured animals. PAC overestimated Q˙ (Q˙Pa) at all Q˙EC settings compared to Q˙A0. The mean bias between both methods was 2.1 L/min in healthy animals and 2.7 L/min after lung injury. The difference between Q˙Pa and Q˙A0 increased with an Q˙EC of 75-125%/Q˙A0 compared to QEC

ZusammenfassungDer Beitrag untersucht am Beispiel des Engagements für Geflüchtete Stärken, Herausforderungen und Probleme freiwilligen Engagements und arbeitet zugleich die Spezifika dieser Form der Hilfe und Solidarität heraus. Die Analyse rekurriert auf eine qualitative Erhebung, die problemzentrierte Interviews mit Engagierten und Leitfadeninterviews mit Expert*innen sowie eine Dokumentenanalyse von politischen, medialen, zivilgesellschaftlichen und wissenschaftlichen Quellen für den Zeitraum von 2011 bis 2018 umfasst. Im Zentrum der Analyse stehen (1) der mediale und gesellschaftliche Außenblick auf die ehrenamtliche Flüchtlingshilfe, (2) multiple Grenzziehungen, -überschreitungen und -erfahrungen im Engagement sowie (3) die Bewältigung von Problemen und Herausforderungen seitens der Engagierten – durch den Ausstieg aus dem Engagement, die Kritik an Engagementbedingungen, die Verheimlichung des Engagements oder die Politisierung der Rolle freiwilliger Hilfe im Strukturwandel des Wohlfahrtsstaats.

Ausgehend von einer qualitativen Studie zu Freiwilligenarbeit im Strukturwandel des Wohlfahrtsstaats entwickelt der Beitrag die Diagnose einer Verzivilgesellschaftlichung der sozialen Frage, die auf die Aktivierung nicht-erwerbsförmiger Sorgetätigkeiten im Rahmen einer sozialpolitischen Gabenökonomie zielt. Eingebettet in konzeptionelle Überlegungen zur Bedeutung von Freiwilligenarbeit werden empirische Beispiele für die tragende Rolle von Freiwilligenarbeit präsentiert, um sodann die Ermöglichungsbedingungen ihrer staatlichen Indienstnahme auszuloten und die politische Ökonomie von Freiwilligenarbeit im Gegenwartskapitalismus in den Blick zu nehmen.

Oxidative stress caused by mechanical ventilation contributes to the pathophysiology of ventilator-induced lung injury (VILI). A key mechanism maintaining redox balance is the upregulation of nuclear factor-erythroid-2-related factor 2 (Nrf2)-dependent antioxidant gene expression. We tested whether pretreatment with an Nrf2-antioxidant response element (ARE) pathway activator tert-butylhydroquinone (tBHQ) protects against VILI. Male C57BL/6J mice were pretreated with an intraperitoneal injection of tBHQ ( n = 10), an equivalent volume of 3% ethanol (EtOH3%, vehicle, n = 13), or phosphate-buffered saline (controls, n = 10) and were then subjected to high tidal volume (HVT) ventilation for a maximum of 4 h. HVT ventilation severely impaired arterial oxygenation ([Formula: see text] = 49 ± 7 mmHg, means ± SD) and respiratory system compliance, resulting in a 100% mortality among controls. Compared with controls, tBHQ improved arterial oxygenation ([Formula: see text] = 90 ± 41 mmHg) and respiratory system compliance after HVT ventilation. In addition, tBHQ attenuated the HVT ventilation-induced development of lung edema and proinflammatory response, evidenced by lower concentrations of protein and proinflammatory cytokines (IL-1β and TNF-α) in the bronchoalveolar lavage fluid, respectively. Moreover, tBHQ enhanced the pulmonary redox capacity, indicated by enhanced Nrf2-depentent gene expression at baseline and by the highest total glutathione concentration after HVT ventilation among all groups. Overall, tBHQ pretreatment resulted in 60% survival ( P < 0.001 vs. controls). Interestingly, compared with controls, EtOH3% reduced the proinflammatory response to HVT ventilation in the lung, resulting in 38.5% survival ( P = 0.0054 vs. controls). In this murine model of VILI, tBHQ increases the pulmonary redox capacity by activating the Nrf2-ARE pathway and protects against VILI. These findings support the efficacy of pharmacological Nrf2-ARE pathway activation to increase resilience against oxidative stress during injurious mechanical ventilation.

Introduction The aim of this study was to examine the root canal system morphology of mandibular incisors by means of micro–computed tomographic imaging. Methods The root canal configuration, physiological foramina, frequency of accessory and connecting canals, and the size and shape of the physiological foramina of 125 mandibular incisors were investigated by means of micro-CT and 3-dimensional imaging software. Root canal configuration of the coronal, middle, and apical thirds and the physiological foramina number are described by a 4-digit system code. Results The most frequent root canal configurations were 1-1-1/1 (56%), 1-2-1/1 (17.6%), and 1-1-1/2 (10.4%); 9 additional different root canal configurations were observed. Single-rooted incisors showed in 80% 1, in 16% 2, and in 4% 3 physiological foramina, respectively. Accessory canals were found in only 13.6% of the investigated teeth. Connecting canals were observed in 36% of the sample, most often in root canal configurations 1-2-1/1 (12.8%) and 2-2-1/1 (7.2%). The morphologic dimensions of a total of 146 physiological foramina were measured. Their mean wide and narrow diameters were 0.24 mm (standard deviation = 0.1 mm) and 0.23 mm (standard deviation = 0.08 mm) when only 1 physiological foramen was present. The physiological foramen shapes observed were oval (56%), round (28.8%), and irregular (15.2%). Conclusions The study provides detailed information about the root canal morphology of anterior teeth in a German population. Within the limitations of the study, the authors recommend according to results obtained in this investigation a final physiological foramen preparation size of ISO 30-35; yet, such a decision should be carefully considered on an individual basis.

Background A peripheral venous catheter (PVC) is the most widely used device for obtaining vascular access, allowing the administration of fluids and medication. Up to 25% of adult patients, and 50% of pediatric patients experience a first-attempt cannulation failure. In addition to patient and clinician characteristics, device features might affect the handling and success rates. The objective of the study was to compare the first-attempt cannulation success rate between PVCs with wings and a port access (Vasofix® Safety, B. Braun, abbreviated hereon in as VS) with those without (Introcan® Safety, B. Braun, abbreviated hereon in as IS) in an anesthesiological cohort. Methods An open label, multi-center, randomized trial was performed. First-attempt cannulation success rates were examined, along with relevant patient, clinician, and device characteristics with univariate and multivariate analyses. Information on handling and adherence to use instructions was gathered, and available catheters were assessed for damage. Results Two thousand three hundred four patients were included in the intention to treat analysis. First-attempt success rate was significantly higher with winged and ported catheters (VS) than with the non-winged, non-ported design (IS) (87.5% with VS vs. 78.2% with IS; PChi PChi P P P = .001). Conclusions First-attempt cannulation success of peripheral, ported, winged catheters was higher compared to non-ported, non-winged devices. The handling of the winged and ported design was better rated by the clinicians. Needle reinsertions are related to an increase in rates of catheter damage and cannulation failure. Trial registration ClinicalTrials.gov, Identifier: NCT02213965, Date: 12/08/2014.

Journal of maps (2022). doi:10.1080/17445647.2021.2009926, Published by Taylor & Francis, London

Additional file 3: Supplemental Table 2. Patient characteristics by center (continued). All data shown as frequencies and percentages. CBF Campus Benjamin Franklin, CVK Campus Virchow Klinikum, CCM Campus Charité Mitte, UCT Universitätsklinikum Tübingen. Missing data is treated as such. Vein status is a subjective variable assigned by the corresponding operator; P-values represent Chi-Square Test, or Fisher’s Exact Test when small cell exceptions were present; missing data is treated as such.

Additional file 1: Supplemental Figure 1. Consort diagram, flowchart; *For one study site (Universitätsklinik Tübingen), only information about completed case report forms are available; # Other reasons include screening failure, urgent operations, and missing documentation; ## Other reasons include missing/incomplete data and drop-out participants.

Additional file 2: Supplemental Table 1. Patient characteristics by center. All data shown as frequencies and percentages. ASA American Society of Anesthesiologists, CBF Campus Benjamin Franklin, CVK Campus Virchow Klinikum, CCM Campus Charité Mitte; UCT Universitätsklinikum Tübingen; P-values represent Chi-Square Test, or Fisher’s Exact Test when small cell exceptions were present; missing data is treated as such.

Additional file 4: Supplemental Table 3. Multivariate analysis without misuse markers; VS: Vasofix® Safety, IS: Introcan® Safety; adult participants only; All data analyzed as categorical variables.

Additional file 5: Supplemental Table 4. Catheter misuse in relation to risk of cannulation failure, detailed by type of catheter. Catheter misuse refers to needle movement, the practice of moving the needle in the cannula prior to puncture or during the catheterization attempt (the manufacturer’s use instructions explicitly warn against such maneuvers).

Additional file 6: Supplemental Table 5. Catheter misuse in relation to risk of catheter damage, detailed by type of catheter. Catheter misuse refers to needle movement, the practice of moving the needle in the cannula prior to puncture or during the catheterization attempt (the manufacturer’s use instructions explicitly warn against such maneuvers). Catheter damage refers to abnormalities in catheter structure, macroscopic or microscopic, such as cuts, tears, compressions or loss of material.

Die alten und neuen Bundesländer unterscheiden sich auch 30 Jahre nach der Systemtransformation in Bezug auf die Verbreitung und Institutionalisierung von Engagement deutlich. Während der Westen über eine kulturell verankerte Engagementtradition verfügt, steht das Engagement im Osten im Ruf, (diskursiv umkämpftes) Neuland zu sein. Der Beitrag argumentiert auf Basis empirischer Forschungsbefunde, dass der Osten auch historisch keinesfalls eine Engagementwüste darstellt, dass sich aber gleichwohl Spezifika des Engagements im Osten zeigen, die im Zusammenhang mit den Folgen der innerdeutschen Spaltung, der Systemtransformation und ihren Folgen zu sehen sind. Diese Folgeerscheinungen müssen zudem im Kontext steigender Erwerbsbeteiligung, des demografischen Wandels und eines Generationenwechsels neu konturiert werden, der Freiwilligenarbeit und Engagement in Ost wie West vor ganz neue Herausforderungen stellt.

Various animal models exist to study the complex pathomechanisms of the acute respiratory distress syndrome (ARDS). These models include pulmo-arterial infusion of oleic acid, infusion of endotoxins or bacteria, cecal ligation and puncture, various pneumonia models, lung ischemia/reperfusion models and, of course, surfactant depletion models, among others. Surfactant depletion produces a rapid, reproducible deterioration of pulmonary gas exchange and hemodynamics and can be induced in anesthetized pigs using repeated lung lavages with 0.9% saline (35 mL/kg body weight, 37 °C). The surfactant depletion model supports investigations with standard respiratory and hemodynamic monitoring with clinically applied devices. But the model suffers from a relatively high recruitability and ventilation with high airway pressures can immediately reduce the severity of the injury by reopening atelectatic lung areas. Thus, this model is not suitable for investigations of ventilator regimes that use high airway pressures. A combination of surfactant depletion and injurious ventilation with high tidal volume/low positive end-expiratory pressure (high Tv/low PEEP) to cause ventilator induced lung injury (VILI) will reduce the recruitability of the resulting lung injury. The advantages of a timely induction and the possibility to perform experimental research in a setting comparable to an intensive care unit are preserved.

Objectives Human health surveillance and food safety monitoring systems use different antimicrobial susceptibility testing (AST) methods. In this study, we compared the MICs of Escherichia coli isolates provided by these methods. Methods E. coli isolates (n = 120) from human urine samples and their MICs were collected from six medical laboratories that used automated AST methods based on bacterial growth kinetic analyses. These isolates were retested using broth microdilution, which is used by the food safety monitoring system. The essential and categorical agreements (EA and CA), very major errors (VME), major errors (ME) and minor errors (mE) for these two methods were calculated for 11 antibiotics using broth microdilution as a reference. For statistical analysis, clinical breakpoints provided by EUCAST were used. Results Five study laboratories used VITEK®2 and one MicroScan (Walkaway Combo Panel). Out of 120 isolates, 118 isolates (98.3%) were confirmed as E. coli. The 99 E. coli isolates from five study laboratories that used VITEK®2 showed high proportions of EA and CA with full agreements for gentamicin, meropenem, imipenem and ertapenem. Additionally, 100% CA was also observed in cefepime. Few VME (0.5%), ME (1.9%) and mE (1.5%) were observed across all antibiotics. One VME for ceftazidime (7.1%) and 12 MEs for ampicillin (29.4%), cefotaxime (2.4%), ciprofloxacin (3.2%), tigecycline (1.5%) and trimethoprim (22.2%) were detected. Conclusions MICs from E. coli isolates produced by VITEK®2 were similar to those determined by broth microdilution. These results will be valuable for comparative analyses of resistance data from human health surveillance and food safety monitoring systems.

Earth science reviews 215, 103496 (2021). doi:10.1016/j.earscirev.2020.103496, Published by Elsevier, Amsterdam [u.a.]

Purpose Admixture of nitric oxide (NO) to the gas inspired with mechanical ventilation can be achieved through continuous, timed, or pulsed injection of NO into the inspiratory limb. The dose and timing of NO injection govern the inspired and intrapulmonary effect site concentrations achieved with different administration modes. Here we test the effectiveness and target reliability of a new mode injecting pulsed NO boluses exclusively during early inspiration. Methods An in vitro lung model was operated under various ventilator settings. Admixture of NO through injection into the inspiratory limb was timed either (i) selectively during early inspiration (“pulsed delivery”), or as customary, (ii) during inspiratory time or (iii) the entire respiratory cycle. Set NO target concentrations of 5–40 parts per million (ppm) were tested for agreement with the yield NO concentrations measured at various sites in the inspiratory limb, to assess the effectiveness of these NO administration modes. Results Pulsed delivery produced inspiratory NO concentrations comparable with those of customary modes of NO administration. At low (450 ml) and ultra-low (230 ml) tidal volumes, pulsed delivery yielded better agreement of the set target (up to 40 ppm) and inspiratory NO concentrations as compared to customary modes. Pulsed delivery with NO injection close to the artificial lung yielded higher intrapulmonary NO concentrations than with NO injection close to the ventilator. The maximum inspiratory NO concentration observed in the trachea (68 ± 30 ppm) occurred with pulsed delivery at a set target of 40 ppm. Conclusion Pulsed early inspiratory phase NO injection is as effective as continuous or non-selective admixture of NO to inspired gas and may confer improved target reliability, especially at low, lung protective tidal volumes.

Cryogenic turning of metastable austenitic steels allows for a surface layer hardening integrated into the machining process, which renders a separate hardening process obsolete. This surface layer hardening is the result of a superposition of strain hardening mechanisms and deformation-induced phase transformation from austenite to martensite. The activation energy required for the latter depends on the chemical composition of the metastable austenitic steel. It can hence be expected that the austenitic stability of the workpiece material varies depending on the batch and that differences in the metallurgical surface layer properties and thus also in the microhardness result after cryogenic turning. Therefore, in this paper, various batches of the metastable austenitic steel AISI 347 were turned utilizing cryogenic cooling with the same machining parameters. The thermomechanical load during the experiments was characterized and the resulting subsurface properties were investigated. The content of deformation-induced α′-martensite was quantified via magnetic sensor measurements and the distribution was examined using optical micrographs of etched cross-sections. It was found that similar amounts of deformation-induced α′-martensite were generated in the workpiece surface layer for all batches examined. Furthermore, the workpieces were analyzed with regard to the maximal hardness increase and the hardness penetration depth based on microhardness measurements. A significant surface layer hardening was achieved for all batches. This shows that surface layer hardening integrated in the manufacturing process is possible regardless of batch-dependent differences in the chemical composition and thus varying austenite stability of the metastable austenitic steel.

In recent years, deformation induced surface hardening when turning was carried out to enhance the component performance of metastable austenitic steels. To induce such a phase transformation from austenite to martensite in the workpiece surface layer, high mechanical loads and low process temperatures are required. Therefore, cryogenic CO2-snow cooling is an appropriate method to assure low temperatures in the workpiece surface layer. In this context, the influence of the process parameters cutting speed, feed, depth of cut and tool cutting edge inclination on the surface morphology in terms of deformation induced surface hardening and resulting surface roughness was investigated. The results show that the deformation induced surface hardening when cryogenic turning is adjustable via a targeted variation of the investigated process parameters. Thus, the morphology of the surface layer and therefore the properties of the component can be adjusted according to the requirements of the application.

The aim of this study was to investigate the nerve supply to the structures in the male lesser pelvis and review its clinical relevance, especially during nerve sparing surgery. Three formalin-embalmed and 16 Thiel-embalmed male hemipelves were used. They were microdissected after repeated treatments with nitric acid diluted 1:10 with milliQ-water. The inferior hypogastric plexus (IHP) is a fan-like structure lateral from the rectum on the fascia of the levator ani. Nerves emerging from the proximal, solid part of the plexus follow the internal iliacal vessels and reach the prostate from dorsolateral. The innervation of the urethra and the corpora cavernosa derives from two origins: one follows the ejaculatory duct and the seminal vesicle, reaching the proximal urethra and the prostate from dorsal; the other follows the inferior vesical artery to reach the prostate from lateral, and then forms the neurovascular bundle on both sides of the prostatic fascia, spreading to the pelvic floor muscles and the corpora cavernosa along with the distal urethra. A connection between the two parts was demonstrated in approximately one third of the samples investigated. The nerve supply to the urinary bladder, the urethra, and the corpora cavernosa emerges mainly from the IHP. The innervation of the proximal urethra and its autonomic muscular structures has a dorsal (ejaculatory duct) and lateral (inferior vesical artery) origin. To maintain good erectile and continence function it is important to save both the dorsal and lateral neurovascular roots. Clin. Anat. 31:788-796, 2018. © 2018 Wiley Periodicals, Inc.

Key points Carbonic anhydrase (CA) inhibitors such as acetazolamide inhibit hypoxic pulmonary vasoconstriction (HPV) in humans and other mammals, but the mechanism of this action remains unknown. It has been postulated that carbonic anhydrase may act as a nitrous anhydrase in vivo to generate nitric oxide (NO) from nitrite and that this formation is increased in the presence of acetazolamide. Acetazolamide reduces HPV in pigs without evidence of any NO generation, whereas nebulized sodium nitrite reduces HPV by NO formation; however; combined infusion of acetazolamide with sodium nitrite inhalation did not further increase exhaled NO concentration over inhaled nitrite alone in pigs exposed to alveolar hypoxia. We conclude that acetazolamide does not function as either a nitrous anhydrase or a nitrite reductase in the lungs of pigs, and probably other mammals, to explain its vasodilating actions in the pulmonary or systemic circulations. Abstract The carbonic anhydrase (CA) inhibitors acetazolamide and its structurally similar analogue methazolamide prevent or reduce hypoxic pulmonary vasoconstriction (HPV) in dogs and humans in vivo, by a mechanism unrelated to CA inhibition. In rodent blood and isolated blood vessels, it has been reported that inhibition of CA leads to increased generation of nitric oxide (NO) from nitrite and vascular relaxation in vitro. We tested the physiological relevance of augmented NO generation by CA from nitrite with acetazolamide in anaesthetized pigs during alveolar hypoxia in vivo. We found that acetazolamide prevents HPV in anaesthetized pigs, as in other mammalian species. A single nebulization of sodium nitrite reduces HPV, but this action wanes in the succeeding 3 h of hypoxia as nitrite is metabolized and excreted. Pulmonary artery pressure reduction and NO formation as measured by exhaled gas concentration from inhaled sodium nitrite were not increased by acetazolamide during alveolar hypoxia. Thus, our data argue against a physiological role of carbonic anhydrase as a nitrous anhydrase or nitrite reductase as a mechanism for its inhibition of HPV in the lung and blood in vivo.

BACKGROUND: After transfusion of senescent red blood cells (RBCs) a considerable fraction is rapidly cleared from the recipients' circulation. Thus, transfusion of senescent RBCs may be less effective in terms of increasing hemoglobin concentration (cHb) after transfusion. STUDY DESIGN AND METHODS: Data were retrospectively obtained in patients who underwent major abdominal surgery between 2006 and 2012. Patients were eligible if they received RBCs during surgery and had at least two arterial blood gas analyses performed. The primary endpoint was the increase of recipients' cHb related to the transfusion of 1 unit of RBCs with respect to different storage periods. Four storage periods were defined according to the distribution of RBC storage of the study population. General estimating equation was used for calculation of the primary endpoint and to adjust for confounding variables. RESULTS: A total of 598 arterial blood gas samples from 120 patients, receiving 429 RBC units, were analyzed. Mean (±SD) RBC storage was 21 (±9) days. RBC storage duration and the increase in recipients' cHb were inversely and gradually related; that is, the older the RBCs, the lower the increase in the recipients' cHb after transfusion (storage

BACKGROUND: Allogeneic red blood cells (RBCs) have the potential to impact the immunosurveillance of the recipient and may therefore increase the risk of recurrence after cancer surgery. In this article the relationship between perioperative RBC transfusion and the risk of recurrence after ovarian cancer surgery is examined. STUDY DESIGN AND METHODS: This is a retrospective cohort analysis of a prospective database of patients who underwent surgery due to primary ovarian cancer between 2006 and 2014 and who had no residual disease after surgery. Patients who did and did not receive perioperative RBC transfusion were compared. The primary endpoint was progression-free survival (PFS). Propensity score matching (PSM) and Cox proportional hazards regression (CPH) was used to control for between-group differences of prognostic determinants. RESULTS: A total of 529 patients with a median follow-up of 51.4 months (95% CI, 46.1-56.5) were eligible for analysis. Of those, 408 patients (77.1%) received allogeneic, leukoreduced RBCs with a median of 4 units (IQR, 2-6) per patient. There was a strong selection bias of prognostic determinants between patients with and without transfusion. In unadjusted analysis, transfusion of RBCs was associated with an increased risk of cancer recurrence (hazard ratio [HR] of PFS 2.71 [95% CI, 1.94-3.77], p < 0.001). After bias reduction, transfusion of RBCs was no longer associated with an increased risk of cancer recurrence, neither in PSM-adjusted (HR 1.03 [95% CI, 0.59-1.80], p = 0.91), nor in multivariable CPH-adjusted analysis (HR 1.26 [95% CI, 0.85-1.86], p = 0.23). CONCLUSION Perioperative transfusion of RBCs did not increase the risk of recurrence after ovarian cancer surgery.

Chemische Grundlagen des Saure-Basen-Haushalts werden in diesem Kapitel ebenso erlautert, wie die unterschiedlichen Puffersysteme und Transport und Elimination von Kohlendioxid. Die Funktionen der Niere bei der Regulation des pH-Wertes sowie der Oxygenierungsstatus des Bluts werden erortert. Zudem werden die typischen Storungen des Saure-Basen-Haushalts bei Patienten vorgestellt.

To investigate the fatigue behavior of metastable austenite steels in the VHCF-regime, high loading frequencies are essential to realize acceptable testing times. Hence, two high-frequency testing systems were used at the authors’ institute: an ultrasonic testing system with a test frequency of 20 000 Hz and also, a servohydraulic system with a test frequency of 980 Hz. In the present study, two different batches of the metastable austenitic stainless steel AISI 347 were investigated. Fatigue tests on metastable austenitic steel AISI 347 batch A were carried out at an ultrasonic test system at a test frequency of 20 000 Hz, at ambient temperature. Because the test rig acts as a mechanical resonant circuit excited by a piezoelectric transducer the specimen must be designed for oscillation in its vibration Eigenmode at the test frequency to assure maximum displacement at the end and maximum stress in the gauge length center, respectively. For analyzing the deformation behavior during the tests, the change in temperature was measured. Additionally, Feritscope™ measurements at the specimen surface were performed ex-situ after defined load cycles. First results showed a pronounced development of phase transformation from paramagnetic face-centered cubic γ-austenite to ferromagnetic body-centered cubic α‘-martensite. Because formation of α‘-martensite influences the transient behavior and high frequency loadings leads to pronounced self-heating of the material, ultrasonic fatigue tests on metastable austenites represent a challenge in controlling of displacement amplitude and limiting the specimen temperature. First investigations on metastable austenitc steel AISI 347 batch B using a servohydraulic test system at a frequency of 980 Hz and a temperature of T = 300 °C resulted in no fatigue failure beyond N = 107 cycles in the VHCF-regime. However, only specimens with a low content of cyclic deformation-induced α‘-martensite achieved the ultimate number of cycles (Nu = 5·108).

Purpose. To validate a small, easy to use and cost-effective augmented marker-based hybrid navigation system for peri-acetabular osteotomy surgery.Methods. A cadaver study including 3 pelvises (6 hip joints) undergoing navigated PAO was performed. Inclination and anteversion of two navigation systems for PAO were compared during acetabular reorientation. The hybrid system consists of a tracking unit which is placed on the patient’s pelvis and an augmented marker which is attached to the patient’s acetabular fragment. The tracking unit sends a video stream of the augmented marker to the host computer. Simultaneously, the augmented marker sends orientation output from an integrated inertial measurement unit (IMU) to the host computer. The host computer then computes the pose of the augmented marker and uses it (if visible) to compute acetabular orientation. If the marker is not visible, the output from the IMU is used to update the orientation. The second system served as ground truth and is a previously developed and validated optical tracking-based navigation system.Results. Mean absolute difference for inclination and anteversion (N = 360) was 1.34 degrees and 1.21 degrees, respectively. The measurements from our system show a very strong correlation to the ground-truth optical tracking-based navigation system for both inclination and anteversion (0.9809 / 0.9711).Conclusion. In this work we successfully demonstrated the feasibility of our system to measure inclination and anteversion during acetabular reorientation.

Introduction Due to the realistic colour, texture conservation and preservation of biomechanical properties, Thiel-embalming is becoming the main embalming procedure for clinical courses and research based on human cadaver material. The aim of this study is to establish a new procedure that allows advanced microdissection of small vessels and intraorganic nerves in Thiel-embalmed material. Material and methods/results After a classical gross anatomical dissection, human hemipelves underwent repetitive application of 3 consecutive steps: (i) maceration with alloy of nitric acid and MiliQ water 1:10 for 24–48 h. (ii) Immersion: the hemipelves were rinsed under tap water for 20–30 min. and placed in a water bath for 1 h. The nerves become more prominent due to the swelling and increased water content. (iii) microdissection under surgical microscope. To facilitate the organ visualization perfusion with polyurethane (Pu4ii, VasQtec ® , Switzerland) in red/blue for arteries/veins respectively has been performed. Conclusion By using the proposed procedure, we performed satisfactory microdissection on Thiel-embalmed samples. The combination with polyurethane vascular casting permits visualization of small arterioles and venules in a range of 20–25 μm. The method is very suitable for demonstration of somatic and vegetative nerves. Branches of the sacral plexuses and autonomic nerves from the superior and inferior hypogastric plexus have been tracked up to the smallest intraorganic branches in a range of 12.5–15 μm. In conclusion, the established combined procedure offers a new possibility for advanced microdissection, which will allow acquisition of clinically relevant information about organ specific micro- vascularization and innervation.

After transfusion of senescent red blood cells (RBCs) a considerable fraction is rapidly cleared from the recipients' circulation. Thus, transfusion of senescent RBCs may be less effective in terms of increasing hemoglobin concentration (cHb) after transfusion.Data were retrospectively obtained in patients who underwent major abdominal surgery between 2006 and 2012. Patients were eligible if they received RBCs during surgery and had at least two arterial blood gas analyses performed. The primary endpoint was the increase of recipients' cHb related to the transfusion of 1 unit of RBCs with respect to different storage periods. Four storage periods were defined according to the distribution of RBC storage of the study population. General estimating equation was used for calculation of the primary endpoint and to adjust for confounding variables.A total of 598 arterial blood gas samples from 120 patients, receiving 429 RBC units, were analyzed. Mean (±SD) RBC storage was 21 (±9) days. RBC storage duration and the increase in recipients' cHb were inversely and gradually related; that is, the older the RBCs, the lower the increase in the recipients' cHb after transfusion (storage 12 days, ΔcHb per unit RBCs +0.82 [95% confidence interval, 0.42-1.21] g/dL, p 0.01; storage 12-20 days, +0.66 [0.46-0.86] g/dL, p 0.01; storage 21-29 days, +0.56 [0.33-0.79] g/dL, p 0.01; storage ≥30 days, +0.39 [0.07 to 0.71] g/dL, p = 0.02).Transfusion of senescent RBCs increased cHb less effectively than transfusion of fresher RBCs.

The aim of this study was to investigate the nerve supply to the structures in the male lesser pelvis and review its clinical relevance, especially during nerve sparing surgery. Three formalin-embalmed and 16 Thiel-embalmed male hemipelves were used. They were microdissected after repeated treatments with nitric acid diluted 1:10 with milliQ-water. The inferior hypogastric plexus (IHP) is a fan-like structure lateral from the rectum on the fascia of the levator ani. Nerves emerging from the proximal, solid part of the plexus follow the internal iliacal vessels and reach the prostate from dorsolateral. The innervation of the urethra and the corpora cavernosa derives from two origins: one follows the ejaculatory duct and the seminal vesicle, reaching the proximal urethra and the prostate from dorsal; the other follows the inferior vesical artery to reach the prostate from lateral, and then forms the neurovascular bundle on both sides of the prostatic fascia, spreading to the pelvic floor muscles and the corpora cavernosa along with the distal urethra. A connection between the two parts was demonstrated in approximately one third of the samples investigated. The nerve supply to the urinary bladder, the urethra, and the corpora cavernosa emerges mainly from the IHP. The innervation of the proximal urethra and its autonomic muscular structures has a dorsal (ejaculatory duct) and lateral (inferior vesical artery) origin. To maintain good erectile and continence function it is important to save both the dorsal and lateral neurovascular roots. Clin. Anat. 31:788-796, 2018. © 2018 Wiley Periodicals, Inc.

To develop a hybrid augmented marker-based navigation system for acetabular reorientation during peri-acetabular osteotomy (PAO). The system consists of a tracking unit attached to the patient’s pelvis, augmented marker attached to the acetabular fragment and a host computer to do all the computations and visualization. The augmented marker is comprised of an external planar Aruco marker facing toward the tracking unit and an internal inertial measurement unit (IMU) to measure its orientation. The orientation output from the IMU is sent to the host computer. The tracking unit streams a live video of the augmented marker to the host computer, where the planar marker is detected and its pose is estimated. A Kalman filter-based sensor fusion combines the output from marker tracking and the IMU. We validated the proposed system using a plastic bone study and a cadaver study. Every time, we compared the inclination and anteversion values measured by the proposed system to those from a previously developed optical tracking-based navigation system. Mean absolute differences for inclination and anteversion were 1.34 ( $$\pm \,1.50$$ ) and 1.21 ( $$\pm \, 1.07$$ ) $$^\circ $$ , respectively, for the cadaver study. Mean absolute differences were 1.63 ( $$\pm \,1.48$$ ) and 1.55 ( $$\pm \,1.49$$ ) $$^\circ $$ for inclination and anteversion for the plastic bone study. In both validation studies, very strong correlations were observed. We successfully demonstrated the feasibility of our system to measure the acetabular orientation during PAO.

Corrosion resistance has been the main scope of the development in high-alloyed low carbon austenitic stainless steels. However, the chemical composition influences not only the passivity but also significantly affects their metastability and, consequently, the transformation as well as the cyclic deformation behavior. In technical applications, the austenitic stainless steels undergo fatigue in low cycle fatigue (LCF), high cycle fatigue (HCF), and very high cycle fatigue (VHCF) regime at room and elevated temperatures. In this context, the paper focuses on fatigue and transformation behavior at ambient temperature and 300 &deg, C of two batches of metastable austenitic stainless steel AISI 347 in the whole fatigue regime from LCF to VHCF. Fatigue tests were performed on two types of testing machines: (i) servohydraulic and (ii) ultrasonic with frequencies: at (i) 0.01 Hz (LCF), 5 and 20 Hz (HCF) and 980 Hz (VHCF), and at (ii) with 20 kHz (VHCF). The results show the significant influence of chemical composition and temperature of deformation induced &acute, martensite formation and cyclic deformation behavior. Furthermore, a &ldquo, true&rdquo, fatigue limit of investigated metastable austenitic stainless steel AISI 347 was identified including the VHCF regime at ambient temperature and elevated temperatures.

Purpose Combination of prone positioning (PrP) and extracorporeal membrane oxygenation (ECMO) might be beneficial in severe acute respiratory distress syndrome (ARDS), because both approaches are recommended. However, PrP during ECMO might be associated with complications such as dislocation of ECMO cannulae. We investigated complications and change of oxygenation effects of PrP during ECMO to identify “responders” and discuss our results considering different definitions of response in the literature. Methods Retrospective analysis of complications, gas exchange, and invasiveness of mechanical ventilation during first and second PrP on ECMO at specified time points (before, during, and after PrP). We used multivariate nonparametric analysis of longitudinal data (MANOVA) to compare changes of mechanical ventilation and hemodynamics associated with the first and second procedures. Results In 12 ECMO patients, 74 PrPs were performed (median ECMO duration: 10 days (IQR: 6.315.5 days)). No dislocations of intravascular catheters/cannulae, endotracheal tubes or chest tubes were observed. Two PrPs had to be interrupted (endotracheal tube obstruction, acute pulmonary embolism). PaO2/FiO2-ratio increased associated with the first and second PrP (p = 0.002) and lasted after PrP in 58% of these turning procedures (“responders”) without changes in ECMO blood flow, respiratory pressures, minute ventilation, portion of spontaneously triggered breathing, and compliance. Hemodynamics did not change with exception of increased mean pulmonary arterial pressure during PrP and decrease after PrP p≤0.001), while norepinephrine dosage decreased (p = 0.03) (MANOVA). Conclusions Prone position during ECMO is safe and improves oxygenation even after repositioning. This might ameliorate hypoxemia and reduce the harm from mechanical ventilation.

Journal of clinical monitoring and computing (2017). doi:10.1007/s10877-017-0040-0, Published by Springer Science + Business Media B.V., Dordrecht [u.a.]

Dank der raschen technischen Entwicklung sowie diverser Strategien zur Fehlerbeobachtung und -vermeidung gilt die Intensivmedizin und Anasthesiologie als ein sicheres Fach. Der Verabschiedung der „Patient Safety in the ICU: The Vienna Declaration“ der ESICM vom Oktober 2009 sowie der „Helsinki Declaration on Patient Safety in Anaesthesiology“ der ESA und EBA vom Juni 2010 ist es zu verdanken, dass europaweit festgelegt wurde, welche der erprobten Sicherheitskonzepte als unerlasslich zu werten sind. Viele der allgemein bekannten Strategien haben ihren Ursprung in primar nichtmedizinischen Bereichen, wie beispielsweise der zivilen Luftfahrt, und sind dort nicht mehr wegzudenken. Solche „high reliability organisations“ konnen diesbezuglich als Vorbilder fur das Gesundheitswesen angesehen werden. Critical-Incident-Reporting-Systeme zur Meldung von Beinahezwischenfallen, Crisis-Resource-Management zur Verbesserung von Teamwork und kommunikativen Fahigkeiten sowie Checklisten, wie die WHO-Checkliste, zahlen zu konkreten Umsetzungen dieser Art. Des Weiteren wurden standardisierte Medikamentenbeschriftungen, Handedesinfektion, Techniken fur die Patientenubergabe und die realitatsnahe Ausbildung am Simulator als Masnahmen zur Verbesserung der Patientensicherheit exemplarisch fur diesen Beitrag ausgewahlt.

Background: This study investigates whether long-term treatment with an angiotensin-converting enzyme inhibitor (ACEI) impairs the haemodynamic regulation during total intravenous anaesthesia (TIVA) for minor surgery. Methods: In a prospective, two-armed observational study, 36 patients undergoing TIVA for minor surgery were studied. Seventeen were taking ACEIs regularly but no other antihypertensive medication (ACEI group); 19 patients without any cardiovascular medication served as controls (non-ACEI group). Haemodynamic variables were measured every minute during induction and every 5 min during surgery. The plasma levels of renin, angiotensin II, vasopressin and catecholamines were measured before and 18 min after the induction of anaesthesia. Results: The mean arterial pressure decreased to the same extent in both the groups during the induction of TIVA. There were also no differences between the groups regarding the heart rate, systolic and diastolic arterial pressure, as well as the use of vasoconstrictors, and fluids during induction and throughout surgery. In the ACEI group, the plasma renin concentration was higher at baseline and after the induction of anaesthesia presumably due to the interruption of the negative renin–angiotensin feedback loop (P

The authors aimed to test the hypothesis that xenon anesthesia limits adverse hypotensive effects of losartan during acute hemorrhage. In six conscious unsedated Beagle dogs, the systemic and pulmonary circulation were monitored invasively, and two subsequent 60-min hypotensive challenges were performed by (a) induction (propofol) and maintenance of anesthesia with isoflurane/remifentanil or xenon/remifentanil and by (b) subsequent hemorrhage (20 mL kg⁻¹ within 5 min) from a central vein. The same amount of blood was retransfused 1 h after hemorrhage. Experiments were performed with or without acute angiotensin II receptor subtype 1 blockade by i.v. losartan (100 μg·kg⁻¹·min⁻¹) starting 45 min before induction of anesthesia. Four experiments were performed in each individual dog. Xenon/remifentanil anesthesia provided higher baseline mean arterial blood pressure (85 ± 6 mmHg) than isoflurane/remifentanil anesthesia (67 ± 3 mmHg). In losartan-treated animals, isoflurane/remifentanil caused significant hypotension (42 ± 4 mmHg for isoflurane/remifentanil vs. 71 ± 6 mmHg for xenon/remifentanil). Independent of losartan, hemorrhage did not induce any further reduction of mean arterial blood pressure or cardiac output in either group. Spontaneous hemodynamic recovery was observed in all groups before retransfusion was started. Losartan did not alter the adrenaline, noradrenaline, and vasopressin response to acute hemorrhage. Losartan potentiates hypotension induced by isoflurane/remifentanil anesthesia but does not affect the hemodynamic stability during xenon/remifentanil anesthesia. Losartan does not deteriorate the hemodynamic adaptation to hemorrhage of 20 mL kg⁻¹ during xenon/remifentanil and isoflurane/remifentanil anesthesia. Therefore, xenon/remifentanil anesthesia protects against circulatory side effects of losartan pretreatment and thus may afford safer therapeutic use of losartan during acute hemorrhage.

Context Complications often occur during the early phase after lung transplantation, and rapid diagnosis is vital. Home spirometry is used to detect early changes in graft function. Bluetooth-equipped cell phones are easy to use and facilitate data transfer from home spirometry. Objective To explore use of home spirometry with Bluetooth data transfer in outpatient lung transplant recipients. Design Single-center prospective randomized controlled trial. Intervention Fifty-six patients were randomized either to home spirometry with data transfer via Bluetooth-equipped cell phones or to home spirometry alone before discharge after lung transplantation. In the Bluetooth group, results were transferred to a database capable of generating alarm messages. Main Outcome Measures Time from onset of symptoms to physician consultation during the first 6 months after lung transplantation was the primary end point. Results Adherence to home spirometry was 97.2% in the Bluetooth group and 95.3% in the home spirometry alone group ( P= .73). Median time to first consultation ( P = .60) and frequency of consultation ( P = .06) did not differ significantly in the 2 groups. Mean scores on the Hospital Anxiety and Depression Scale were lower in patients in the Bluetooth group (1.5; range, 0.0–4.0) than in the home spirometry alone group (4.0; range, 2.0–6.0; P = .04). Conclusion Home spirometry with data transfer is feasible and safe in lung transplant recipients. Compared with home spirometry alone, additional data transfer was equally effective regarding the time interval from symptom onset to consultation. Patients in the Bluetooth group reported less anxiety, which may improve emotional well-being.