Detection of human metabolites using multi-capillary columns coupled to ion mobility spectrometers

The human breath contains indicators of human health and delivers information about different metabolism processes of the body. The detection and attribution of these markers provide the possibility for new, non-invasive diagnostic methods. In the recent study, ion mobility spectrometers are used to detect different volatile organic metabolites in human breath directly. By coupling multi-capillary columns using ion mobility spectrometers detection limits down to the ng/L and pg/L range are achieved. The sampling procedure of human breath as well as the detection of different volatiles in human breath are described in detail. Reduced mobilities and detection limits for different analytes occurring in human breath are reported. In addition, spectra of exhaled air using ion mobility spectrometers obtained without any pre-concentration are presented and discussed in detail. Finally, the potential use of IMS with respect to lung infection diseases will be considered.

A novel, non-invasive, online-monitoring, versatile and easy plant-based probe for measuring leaf water status

A high-precision pressure probe is described which allows non-invasive online-monitoring of the water relations of intact leaves. Real-time recording of the leaf water status occurred by data transfer to an Internet server. The leaf patch clamp pressure probe measures the attenuated pressure, P(p), of a leaf patch in response to a constant clamp pressure, P(clamp). P(p) is sensed by a miniaturized silicone pressure sensor integrated into the device. The magnitude of P(p) is dictated by the transfer function of the leaf, T(f), which is a function of leaf patch volume and ultimately of cell turgor pressure, P(c), as shown theoretically. The power function T(f)=f(P(c)) theoretically derived was experimentally confirmed by concomitant P(p) and P(c) measurements on intact leaflets of the liana Tetrastigma voinierianum under greenhouse conditions. Simultaneous P(p) recordings on leaflets up to 10 m height above ground demonstrated that changes in T(f) induced by P(c) changes due to changes of microclimate and/or of the irrigation regime were sensitively reflected in corresponding changes of P(p). Analysis of the data show that transpirational water loss during the morning hours was associated with a transient rise in turgor pressure gradients within the leaflets. Subsequent recovery of turgescence during the afternoon was much faster than the preceding transpiration-induced water loss if the plants were well irrigated. Our data show the enormous potential of the leaf patch clamp pressure probe for leaf water studies including unravelling of the hydraulic communication between neighbouring leaves and over long distances within tall plants (trees).

[Noninvasive Mechanical Ventilation in Acute Respiratory Failure]

The non-invasive ventilation (NIV) is widespread in the clinical medicine and has attained meanwhile a high value in the clinical daily routine. The application of NIV reduces the length of ICU stay and hospitalization as well as mortality of patients with hypercapnic acute respiratory failure. Patients with acute respiratory failure in context of a cardiopulmonary edema should be treated in addition to necessary cardiological interventions with continuous positive airway pressure (CPAP) or NIV. In case of other forms of acute hypoxaemic respiratory failure it is recommended the application of NIV to be limited to mild forms of ARDS as the application of NIV in severe forms of ARDS is associated with higher rates of treatment failure and mortality. In weaning process from invasive ventilation the NIV reduces the risk of reintubation essentially in hypercapnic patients. A delayed intubation of patients with NIV failure leads to an increase of mortality and should therefore be avoided. With appropriate monitoring in intensive care NIV can also be successfully applied in pediatric patients with acute respiratory insufficiency. Furthermore NIV can be useful within palliative care for reduction of dyspnea and improving quality of life. The aim of the guideline update is, taking into account the growing scientific evidence, to outline the advantages as well as the limitations of NIV in the treatment of acute respiratory failure in daily clinical practice and in different indications.

[Prolonged Weaning - S2k-Guideline Published by the German Respiratory Society]

Mechanical ventilation (MV) is an essential part of modern intensive care medicine. MV is performed in patients with severe respiratory failure caused by insufficiency of respiratory muscles and/or lung parenchymal disease when/after other treatments, (i. e. medication, oxygen, secretion management, continuous positive airway pressure or nasal highflow) have failed.MV is required to maintain gas exchange and to buy time for curative therapy of the underlying cause of respiratory failure. In the majority of patients weaning from MV is routine and causes no special problems. However, about 20 % of patients need ongoing MV despite resolution of the conditions which precipitated the need for MV. Approximately 40 - 50 % of time spent on MV is required to liberate the patient from the ventilator, a process called "weaning."There are numberous factors besides the acute respiratory failure that have an impact on duration and success rate of the weaning process such as age, comorbidities and conditions and complications acquired in the ICU. According to an international consensus conference "prolonged weaning" is defined as weaning process of patients who have failed at least three weaning attempts or require more than 7 days of weaning after the first spontaneous breathing trial (SBT). Prolonged weaning is a challenge, therefore, an inter- and multi-disciplinary approach is essential for a weaning success.In specialised weaning centers about 50 % of patients with initial weaning failure can be liberated from MV after prolonged weaning. However, heterogeneity of patients with prolonged weaning precludes direct comparisons of individual centers. Patients with persistant weaning failure either die during the weaning process or are discharged home or to a long term care facility with ongoing MV.Urged by the growing importance of prolonged weaning, this Sk2-guideline was first published in 2014 on the initiative of the German Respiratory Society (DGP) together with other scientific societies involved in prolonged weaning. Current research and study results, registry data and experience in daily practice made the revision of this guideline necessary.The following topics are dealt with in the guideline: Definitions, epidemiology, weaning categories, the underlying pathophysiology, prevention of prolonged weaning, treatment strategies in prolonged weaning, the weaning unit, discharge from hospital on MV and recommendations for end of life decisions.Special emphasis in the revision of the guideline was laid on the following topics:- A new classification of subgroups of patients in prolonged weaning- Important aspects of pneumological rehabilitation and neurorehabilitation in prolonged weaning- Infrastructure and process organization in the care of patients in prolonged weaning in the sense of a continuous treatment concept- Therapeutic goal change and communication with relativesAspects of pediatric weaning are given separately within the individual chapters.The main aim of the revised guideline is to summarize current evidence and also expert based- knowledge on the topic of "prolonged weaning" and, based on the evidence and the experience of experts, make recommendations with regard to "prolonged weaning" not only in the field of acute medicine but also for chronic critical care.Important addressees of this guideline are Intensivists, Pneumologists, Anesthesiologists, Internists, Cardiologists, Surgeons, Neurologists, Pediatricians, Geriatricians, Palliative care clinicians, Rehabilitation physicians, Nurses in intensive and chronic care, Physiotherapists, Respiratory therapists, Speech therapists, Medical service of health insurance and associated ventilator manufacturers.

[Position Paper for the State of the Art Application of Respiratory Support in Patients with COVID-19 - German Respiratory Society]

Against the background of the pandemic caused by infection with the SARS-CoV-2, the German Society for Pneumology and Respiratory Medicine (DGP e.V.), in cooperation with other associations, has designated a team of experts in order to answer the currently pressing questions about therapy strategies in dealing with COVID-19 patients suffering from acute respiratory insufficiency (ARI).The position paper is based on the current knowledge that is evolving daily. Many of the published and cited studies require further review, also because many of them did not undergo standard review processes.Therefore, this position paper is also subject to a continuous review process and will be further developed in cooperation with the other professional societies.This position paper is structured into the following five topics:1. Pathophysiology of acute respiratory insufficiency in patients without immunity infected with SARS-CoV-22. Temporal course and prognosis of acute respiratory insufficiency during the course of the disease3. Oxygen insufflation, high-flow oxygen, non-invasive ventilation and invasive ventilation with special consideration of infectious aerosol formation4. Non-invasive ventilation in ARI5. Supply continuum for the treatment of ARIKey points have been highlighted as core statements and significant observations. Regarding the pathophysiological aspects of acute respiratory insufficiency (ARI), the pulmonary infection with SARS-CoV-2 COVID-19 runs through three phases: early infection, pulmonary manifestation and severe hyperinflammatory phase.There are differences between advanced COVID-19-induced lung damage and those changes seen in Acute Respiratory Distress Syndromes (ARDS) as defined by the Berlin criteria. In a pathophysiologically plausible - but currently not yet histopathologically substantiated - model, two types (L-type and H-type) are distinguished, which correspond to an early and late phase. This distinction can be taken into consideration in the differential instrumentation in the therapy of ARI.The assessment of the extent of ARI should be carried out by an arterial or capillary blood gas analysis under room air conditions and must include the calculation of the oxygen supply (measured from the variables of oxygen saturation, the Hb value, the corrected values of the Hüfner number and the cardiac output). In principle, aerosols can cause transmission of infectious viral particles. Open systems or leakage systems (so-called vented masks) can prevent the release of respirable particles. Procedures in which the invasive ventilation system must be opened, and endotracheal intubation must be carried out are associated with an increased risk of infection.The protection of personnel with personal protective equipment should have very high priority because fear of contagion must not be a primary reason for intubation. If the specifications for protective equipment (eye protection, FFP2 or FFP-3 mask, gown) are adhered to, inhalation therapy, nasal high-flow (NHF) therapy, CPAP therapy or NIV can be carried out according to the current state of knowledge without increased risk of infection to the staff. A significant proportion of patients with respiratory failure presents with relevant hypoxemia, often also caused by a high inspiratory oxygen fraction (FiO2) including NHF, and this hypoxemia cannot be not completely corrected. In this situation, CPAP/NIV therapy can be administered under use of a mouth and nose mask or a respiratory helmet as therapy escalation, as long as the criteria for endotracheal intubation are not fulfilled.In acute hypoxemic respiratory insufficiency, NIV should be performed in an intensive care unit or in a comparable unit by personnel with appropriate expertise. Under CPAP/NIV, a patient can deteriorate rapidly. For this reason, continuous monitoring with readiness to carry out intubation must be ensured at all times. If CPAP/NIV leads to further progression of ARI, intubation and subsequent invasive ventilation should be carried out without delay if no DNI order is in place.In the case of patients in whom invasive ventilation, after exhausting all guideline-based measures, is not sufficient, extracorporeal membrane oxygenation procedure (ECMO) should be considered to ensure sufficient oxygen supply and to remove CO2.

Foliar water supply of tall trees: evidence for mucilage-facilitated moisture uptake from the atmosphere and the impact on pressure bomb measurements

The water supply to leaves of 25 to 60 m tall trees (including high-salinity-tolerant ones) was studied. The filling status of the xylem vessels was determined by xylem sap extraction (using jet-discharge, gravity-discharge, and centrifugation) and by (1)H nuclear magnetic resonance imaging of wood pieces. Simultaneously, pressure bomb experiments were performed along the entire trunk of the trees up to a height of 57 m. Clear-cut evidence was found that the balancing pressure (P(b)) values of leafy twigs were dictated by the ambient relative humidity rather than by height. Refilling of xylem vessels of apical leaves (branches) obviously mainly occurred via moisture uptake from the atmosphere. These findings could be traced back to the hydration and rehydration of mucilage layers on the leaf surfaces and/or of epistomatal mucilage plugs. Xylem vessels also contained mucilage. Mucilage formation was apparently enforced by water stress. The observed mucilage-based foliar water uptake and humidity dependency of the P(b) values are at variance with the cohesion-tension theory and with the hypothesis that P(b) measurements yield information about the relationships between xylem pressure gradients and height.

The impact of lipid distribution, composition and mobility on xylem water refilling of the resurrection plant Myrothamnus flabellifolia

•  Lipids play a crucial role in the maintenance of the structural and functional integrity of the water-conducting elements and cells of the resurrection plant Myrothamnus flabellifolia during complete dehydration. •  Lipid composition, mobility and distribution within the internodal and nodal xylem regions (including short shoots and leaves) were investigated in the presence and absence of water by using various nuclear magnetic resonance (NMR) spectroscopy and imaging techniques differing greatly in the level of spatial resolution and acquisition of lipid parameters. •  Significant findings include: a discontinuity in the branch xylem between an inner zone where no water moves and an outer zone where the water moves; the blocking of water movement in the inner zone by lipids that are not dispersed by water, and the facilitation of water advance in the xylem elements and pits of the outer zone by water-dispersed lipids; the relative impermeability of leaf trace xylem to the rehydrating water and, hence, the relative hydraulic isolation of the leaves. •  These results elucidated part of the strategy used by the resurrection plant to cope with extreme drought and to minimize transpirational water loss upon hydration.

Effects of environmental parameters and irrigation on the turgor pressure of banana plants measured using the non-invasive, online monitoring leaf patch clamp pressure probe

Turgor pressure provides a sensitive indicator for irrigation scheduling. Leaf turgor pressure of Musa acuminate was measured by using the so-called leaf patch clamp pressure probe, i.e. by application of an external, magnetically generated and constantly retained clamp pressure to a leaf patch and determination of the attenuated output pressure P(p) that is highly correlated with the turgor pressure. Real-time recording of P(p) values was made using wireless telemetric transmitters, which send the data to a receiver base station where data are logged and transferred to a GPRS modem linked to an Internet server. Probes functioned over several months under field and laboratory conditions without damage to the leaf patch. Measurements showed that the magnetic-based probe could monitor very sensitively changes in turgor pressure induced by changes in microclimate (temperature, relative humidity, irradiation and wind) and irrigation. Irrigation effects could clearly be distinguished from environmental effects. Interestingly, oscillations in stomatal aperture, which occurred frequently below turgor pressures of 100 kPa towards noon at high transpiration or at high wind speed, were reflected in the P(p) values. The period of pressure oscillations was comparable with the period of oscillations in transpiration and photosynthesis. Multiple probe readings on individual leaves and/or on several leaves over the entire height of the plants further emphasised the great impact of this non-invasive turgor pressure sensor system for elucidating the dynamics of short- and long-distance water transport in higher plants.

[Prolonged weaning: S2k-guideline published by the German Respiratory Society]

Mechanical ventilation (MV) is an essential part of modern intensive care medicine. MV is performed in patients with severe respiratory failure caused by insufficiency of the respiratory muscles and/or lung parenchymal disease when/after other treatments, i. e. oxygen, body position, secretion management, medication or non invasive ventilation have failed.In the majority of ICU patients weaning is routine and does not present any problems. Nevertheless 40-50 % of the time during mechanical ventilation is spent on weaning. About 20 % of patients need continued MV despite resolution of the conditions which originally precipitated the need for MV.There maybe a combination of reasons; chronic lung disease, comorbidities, age and conditions acquired in ICU (critical care neuromyopathy, psychological problems). According to an International Consensus Conference the criteria for "prolonged weaning" are fulfilled if patients fail at least three weaning attempts or require more than 7 days of weaning after the first spontaneous breathing trial. Prolonged weaning is a challenge. An inter- and multi-disciplinary approach is essential for weaning success. Complex, difficult to wean patients who fulfill the criteria for "prolonged weaning" can still be successfully weaned in specialised weaning units in about 50% of cases.In patients with unsuccessful weaning, invasive mechanical ventilation has to be arranged either at home or in a long term care facility.This S2-guideline was developed because of the growing number of patients requiring prolonged weaning. It is an initiative of the German Respiratory Society (Deutsche Gesellschaft für Pneumologie und Beatmungsmedizin e. V., DGP) in cooperation with other societies engaged in the field.The guideline is based on a systematic literature review of other guidelines, the Cochrane Library and PubMed.The consensus project was chaired by the Association of Scientific Medical Societies in Germany (Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften, AWMF) based on a formal interdisciplinary process applying the Delphi-concept. The guideline covers the following topics: Definitions, epidemiology, weaning categories, pathophysiology, the spectrum of treatment strategies, the weaning unit, discharge from hospital on MV and recommendations for end of life decisions. Special issues relating to paediatric patients were considered at the end of each chapter.The target audience for this guideline are intensivists, pneumologists, anesthesiologists, internists, cardiologists, surgeons, neurologists, pediatricians, geriatricians, palliative care clinicians, nurses, physiotherapists, respiratory therapists, ventilator manufacturers.The aim of the guideline is to disseminate current knowledge about prolonged weaning to all interested parties. Because there is a lack of clinical research data in this field the guideline is mainly based on expert opinion.

[S2k Guideline - Recommendations for Inpatient Therapy of Patients with COVID-19]

Since December 2019, the novel coronavirus SARS-CoV-2 (Severe Acute Respiratory Syndrome - Corona Virus-2) has been spreading rapidly in the sense of a global pandemic. This poses significant challenges for clinicians and hospitals and is placing unprecedented strain on the healthcare systems of many countries. The majority of patients with Coronavirus Disease 2019 (COVID-19) present with only mild symptoms such as cough and fever. However, about 6 % require hospitalization. Early clarification of whether inpatient and, if necessary, intensive care treatment is medically appropriate and desired by the patient is of particular importance in the pandemic. Acute hypoxemic respiratory insufficiency with dyspnea and high respiratory rate (> 30/min) usually leads to admission to the intensive care unit. Often, bilateral pulmonary infiltrates/consolidations or even pulmonary emboli are already found on imaging. As the disease progresses, some of these patients develop acute respiratory distress syndrome (ARDS). Mortality reduction of available drug therapy in severe COVID-19 disease has only been demonstrated for dexamethasone in randomized controlled trials. The main goal of supportive therapy is to ensure adequate oxygenation. In this regard, invasive ventilation and repeated prone positioning are important elements in the treatment of severely hypoxemic COVID-19 patients. Strict adherence to basic hygiene, including hand hygiene, and the correct wearing of adequate personal protective equipment are essential when handling patients. Medically necessary actions on patients that could result in aerosol formation should be performed with extreme care and preparation.

Azelastine eye-drops in seasonal allergic conjunctivitis or rhinoconjunctivitis. A double-blind, randomized, placebo-controlled study

This study was carried out to assess the efficacy of 0.025% and 0.05% azelastine eye-drops in patients with seasonal allergic conjunctivitis of > or = 1 year's duration. A total of 151 patients received 0.025% or 0.05% azelastine eye-drops or placebo b.i.d. for 14 days according to a double-blind, randomized, placebo-controlled, parallel-dosing design; 129 patients completed the study as planned. The three target symptoms, scored on 4-point scales, were itching, lacrimation, and redness of the eyes; responders were patients whose symptom sum score decreased by > or = 3 from a baseline score of > or = 6 by day 3. Mean scores of these and five other symptoms were recorded also on days 7 and 14, and patients kept daily diaries of the three main symptoms and swollen eyelids. Responder rates were 73% for 0.025% (P=0.115 vs placebo) and 82% for 0.05% azelastine eye-drops (P=0.011 vs placebo) and 56% for placebo. The time courses of the mean (investigators' and patients') scores for the three main symptoms reflected the dose-dependent effect of azelastine eye-drops. One patient each from the two azelastine groups and three from the placebo group withdrew because of inefficacy. Adverse drug reactions were reported by 14 and 24 patients receiving 0.025% and 0.05% azelastine eye-drops, respectively, and by eight placebo patients. These reactions were mainly slight application site reactions and taste perversion (bitter or unpleasant taste). Azelastine eye-drops are effective and well tolerated at a dose of 0.05% for the treatment of seasonal allergic conjunctivitis.

A non-invasive probe for online-monitoring of turgor pressure changes under field conditions

An advanced non-invasive, field-suitable and inexpensive leaf patch clamp pressure probe for online-monitoring of the water relations of intact leaves is described. The probe measures the attenuated output patch clamp pressure, P(p), of a clamped leaf in response to an externally applied input pressure, P(clamp). P(clamp) is generated magnetically. P(p) is sensed by a pressure sensor integrated into the magnetic clamp. The magnitude of P(p) depends on the transfer function, T(f), of the leaf cells. T(f) consists of a turgor pressure-independent (related to the compression of the cuticle, cell walls and other structural elements) and a turgor pressure-dependent term. T(f) is dimensionless and assumes values between 0 and 1. Theory shows that T(f) is a power function of cell turgor pressure P(c). Concomitant P(p) and P(c) measurements on grapevines confirmed the relationship between T(f) and P(c). P(p) peaked if P(c) approached zero and assumed low values if P(c) reached maximum values. The novel probe was successfully tested on leaves of irrigated and non-irrigated grapevines under field conditions. Data show that slight changes in the microclimate and/or water supply (by irrigation or rain) are reflected very sensitively in P(p).

[Exercise testing in respiratory medicine]

This document replaces the DGP recommendations published in 1998. Based on recent studies and a consensus conference, the indications, choice and performance of the adequate exercise testing method in its necessary technical and staffing setting are discussed. Detailed recommendations are provided: for arterial blood gas analysis and right heart catherterization during exercise, 6-minute walk test, spiroergometry, and stress echocardiography. The correct use of different exercise tests is discussed for specific situations in respiratory medicine: exercise induced asthma, monitoring of physical training or therapeutical interventions, preoperative risk stratification, and evaluation in occupational medicine.

[Non-invasive ventilation as treatment for acute respiratory insufficiency. Essentials from the new S3 guidelines]

BACKGROUND

Scientific evidence is accumulating that non-invasive ventilation (NIV) may be beneficial for different patient groups with acute respiratory insufficiency (ARI). The aim of the new S3 guidelines is to propagate evidence-based knowledge about the indications and limitations of NIV in clinical practice.

METHODS

A total of 28 experts from 12 German medical societies were involved in the process of development of the present guidelines. These experts systematically analyzed approximately 2,900 publications. Finally, the recommendations were discussed and approved in two consensus conferences.

RESULTS

In hypercapnic ARI, NIV reduces the length of stay and mortality during intensive care treatment [grade A recommendation (A)]. Patients with cardiopulmonary edema should be treated with continuous positive airway pressure (CPAP) or NIV (A). For immunocompromized patients with ARI, NIV reduces the mortality (A). In patients with postextubation respiratory failure and during weaning from mechanical ventilation, NIV reduces the risk of reintubation (A). For patients who decline to be ventilated invasively, NIV may be an acceptable alternative (B). Non-invasive ventilation can also successfully be used in pediatric patients with ARI caused by different reasons (C). In acute respiratory distress syndrome (ARDS) NIV cannot generally be recommended because the failure rate is relatively high.

CONCLUSION

Non-invasive ventilation is still not as widely implemented in clinical medicine as would be expected on the basis of the scientific literature. The aim of the present guidelines is to further propagate NIV for the treatment of ARI.

The mechanisms of refilling of xylem conduits and bleeding of tall birch during spring

Seasonal variations in osmolality and components of xylem sap in tall birch trees were determined using several techniques. Xylem sap was extracted from branch and trunk sections of 58 trees using the very rapid gas bubble-based jet-discharge method. The 5-cm long wood pieces were taken at short intervals over the entire tree height. The data show that large biphasic osmolality gradients temporarily exist within the conducting xylem conduits during leaf emergence (up to 272 mosmol x kg(-1) at the apex). These gradients (arising mainly from glucose and fructose) were clearly held within the xylem conduit as demonstrated by (1)H NMR imaging of intact twigs. Refilling experiments with benzene, sucrose infusion, electron and light microscopy, as well as (1)H NMR chemical shift microimaging provided evidence that the xylem of birch represents a compartment confined by solute-reflecting barriers (radial: lipid linings/lipid bodies; axial: presumably air-filled spaces). These features allow transformation of osmolality gradients into osmotic pressure gradients. Refilling of the xylem occurs by a dual mechanism: from the base (by root pressure) and from the top (by hydrostatic pressure generated by xylem-bound osmotic pressure). The generation of osmotic pressure gradients was accompanied by bleeding. Bleeding could be observed at a height of up to 21 m. Bleeding rates measured at a given height decreased exponentially with time. Evidence is presented that the driving force for bleeding is the weight of the static water columns above the bleeding point. The pressure exerted by the water columns and the bleeding volume depend on the water-filling status of (communicating) vessels.

[German recommendations for treatment of critically ill patients with COVID-19-version 3 : S1-guideline]

Seit Dezember 2019 verbreitet sich das neuartige Coronavirus SARS-CoV‑2 (Severe Acute Respiratory Syndrome – Corona Virus-2) rasch im Sinne einer weltweiten Pandemie. Dies stellt Kliniker und Krankenhäuser vor große Herausforderungen und belastet die Gesundheitssysteme vieler Länder in einem nie dagewesenen Ausmaß. Die Mehrheit der Patienten zeigt lediglich milde Symptome der sogenannten Coronavirus Disease 2019 (COVID-19). Dennoch benötigen etwa 5–8 % eine intensivmedizinische Behandlung. Die akute hypoxämische respiratorische Insuffizienz mit Dyspnoe und hoher Atemfrequenz (>30/Min) führt in der Regel zur Aufnahme auf die Intensivstation. Oft finden sich dann bereits bilaterale pulmonale Infiltrate/Konsolidierungen oder auch Lungenembolien in der Bildgebung. Im weiteren Verlauf entwickeln viele Patienten ein Acute Respiratory Distress Syndrome (ARDS). Eine klinische Wirksamkeit einer medikamentösen Therapie bei schwerer COVID-Erkrankung (hospitalisierte Patienten) ist bisher für Remdesivir und Dexamethason nachgewiesen. Das Hauptziel der supportiven Therapie ist es eine ausreichende Oxygenierung sicherzustellen. Die invasive Beatmung und wiederholte Bauchlagerung sind dabei wichtige Elemente in der Behandlung von schwer hypoxämischen COVID-19 Patienten. Die strikte Einhaltung der Basishygiene, einschließlich der Händehygiene, sowie das korrekte Tragen von adäquater persönlicher Schutzausrüstung sind im Umgang mit den Patienten unabdingbar. Prozeduren, die zur Aerosolbildung führen könnten, sollten falls nötig, mit äußerster Sorgfalt und Vorbereitung durchgeführt werden.

S2k-Guideline "Prolonged Weaning"

All mechanically ventilated patients must be weaned from the ventilator at some stage. According to an International Consensus Conference the criteria for "prolonged weaning" are fulfilled if patients fail at least 3 weaning attempts (i. e. spontaneous breathing trial, SBT) or require more than 7 days of weaning after the first SBT. This occurs in about 15 - 20 % of patients.Because of the growing number of patients requiring prolonged weaning a German guideline on prolonged weaning has been developed. It is an initiative of the German Respiratory Society (Deutsche Gesellschaft für Pneumologie und Beatmungsmedizin e. V., DGP) in cooperation with other societies (see acknowledgement) engaged in the field chaired by the Association of Scientific and Medical Societies in Germany (Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften, AWMF).This guideline deals with the definition, epidemiology, weaning categories, underlying pathophysiology, therapeutic strategies, the weaning unit, transition to out-of-hospital ventilation and therapeutic recommendations for end of life care. This short version summarises recommendations on prolonged weaning from the German guideline.

Distribution and function of epistomatal mucilage plugs

Investigation of 67 gymnosperm and angiosperm species belonging to 25 orders shows that epistomatal mucilage plugs are a widespread phenomenon. Measurements of the leaf water status by using the leaf patch clamp pressure technique suggest that the mucilage plugs are involved in moisture uptake and buffering leaf cells against complete turgor pressure loss at low humidity.

Early Detection and Prevention of Schizophrenic Psychosis-A Review

Psychotic disorders often run a chronic course and are associated with a considerable emotional and social impact for patients and their relatives. Therefore, early recognition, combined with the possibility of preventive intervention, is urgently warranted since the duration of untreated psychosis (DUP) significantly determines the further course of the disease. In addition to established diagnostic tools, neurobiological factors in the development of schizophrenic psychoses are increasingly being investigated. It is shown that numerous molecular alterations already exist before the clinical onset of the disease. As schizophrenic psychoses are not elicited by a single mutation in the deoxyribonucleic acid (DNA) sequence, epigenetics likely constitute the missing link between environmental influences and disease development and could potentially serve as a biomarker. The results from transcriptomic and proteomic studies point to a dysregulated immune system, likely evoked by epigenetic alterations. Despite the increasing knowledge of the neurobiological mechanisms involved in the development of psychotic disorders, further research efforts with large population-based study designs are needed to identify suitable biomarkers. In conclusion, a combination of blood examinations, functional imaging techniques, electroencephalography (EEG) investigations and polygenic risk scores should be considered as the basis for predicting how subjects will transition into manifest psychosis.

[Exercise Testing in Respiratory Medicine - DGP Recommendations]

This document replaces the DGP recommendations published in 1998 and 2013. Based on recent studies and a consensus conference, the indications, choice and performance of the adequate exercise testing method and its necessary technical and staffing setting are discussed. Detailed recommendations are provided: for blood gas analysis and right heart catheterization during exercise, walk tests, spiroergometry, and stress echocardiography. The correct use of different exercise tests is discussed for specific situations in respiratory medicine: exercise induced asthma, obesity, monitoring of rehabilitation or therapeutical interventions, preoperative risk stratification, and evaluation in occupational medicine.

Recommendations for treatment of critically ill patients with COVID-19 : Version 3 S1 guideline

Since December 2019 a novel coronavirus (severe acute respiratory syndrome coronavirus 2, SARS-CoV-2) has rapidly spread around the world resulting in an acute respiratory illness pandemic. The immense challenges for clinicians and hospitals as well as the strain on many healthcare systems has been unprecedented.The majority of patients present with mild symptoms of coronavirus disease 2019 (COVID-19); however, 5-8% become critically ill and require intensive care treatment. Acute hypoxemic respiratory failure with severe dyspnea and an increased respiratory rate (>30/min) usually leads to intensive care unit (ICU) admission. At this point bilateral pulmonary infiltrates are typically seen. Patients often develop a severe acute respiratory distress syndrome (ARDS).So far, remdesivir and dexamethasone have shown clinical effectiveness in severe COVID-19 in hospitalized patients. The main goal of supportive treatment is to ascertain adequate oxygenation. Invasive mechanical ventilation and repeated prone positioning are key elements in treating severely hypoxemic COVID-19 patients.Strict adherence to basic infection control measures (including hand hygiene) and correct use of personal protection equipment (PPE) are essential in the care of patients. Procedures that lead to formation of aerosols should be carried out with utmost precaution and preparation.

[Responsibilities of Weaning Centers during the COVID-19 Pandemic Outbreak - Recommendations for the Assignment of ICU Capacities in COVID-19 Patients as shown by the Berlin-Brandenburg POST-SAVE-Model]

The enormous increase in patients with severe respiratory distress due to the COVID-19 pandemic outbreak requires a systematic approach to optimize ventilated patient at risk flow. A standardised algorithm called "SAVE" was developed to distribute patients with COVID-19 respiratory distress syndrome requiring invasive ventilation. This program is established by now in Berlin. An instrumental bottleneck of this approach is the vacant slot assignment in the intensive care unit to guarantee constant patient flow. The transfer of the patients after acute care treatment is needed urgently to facilitate the weaning process. In a next step we developed a triage algorithm to identify patients at SAVE intensive care units with potential to wean and transfer to weaning institutions - we called POST SAVE. This manuscript highlights the algorithms including the use of a standardised digital evaluation tool, the use of trained navigators to facilitate the communication between SAVE intensive care units and weaning institutions and the establishment of a prospective data registry for patient assignment and reevaluation of the weaning potential in the future.