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For the purposes of this guideline, a diving accident is defined as an event that is either potentially life-threatening or hazardous to health as a result of a reduction in ambient pressure while diving or in other hyperbaric atmospheres with and without diving equipment. This national consensus-based guideline (development grade S2k) presents the current state of knowledge and recommendations on the diagnosis and treatment of diving accident victims. The treatment of a breath-hold diver as well as children and adolescents does not differ in principle.In this regard only unusual tiredness and itching without visible skin changes are mild symptoms.The key action statements: on-site 100% oxygen first aid treatment, immobilization/no unnecessary movement, fluid administration and telephone consultation with a diving medicine specialist are recommended.Hyperbaric oxygen therapy (HBOT) remains unchanged as the established treatment in severe cases, as there are no therapeutic alternatives. The basic treatment scheme recommended for diving accidents is hyperbaric oxygenation at 280 kPa., Ein Tauchunfall im Sinne dieser Leitlinie ist ein potenziell lebensbedrohliches oder gesundheitsschädigendes Ereignis, hervorgerufen durch Abfall des Umgebungsdruckes beim Tauchen oder aus sonstiger hyperbarer Atmosphäre mit und ohne Tauchgerät. Diese nationale S2k-Leitlinie legt den aktuellen Stand der Erkenntnisse und der konsentierten Empfehlungen in der Diagnostik und Behandlung von Patienten nach Tauchunfällen dar. Die Behandlung von Apnoetauchern sowie Kindern und Jugendlichen unterscheidet sich prinzipiell nicht.Milde Symptome sind nur die auffällige Müdigkeit und ein Hautjucken ohne sichtbare Hautveränderungen.Wesentliche Bedeutung bei der Versorgung von Tauchunfällen hat die frühzeitige Atmung von 100%igem Sauerstoff. Weiterhin werden die Ruhiglagerung/keine unnötige Bewegung, eine moderate Flüssigkeitsgabe und eine Taucherärztliche Telefonberatung empfohlen.Die hyperbare Sauerstofftherapie (HBOT) ist bei schweren Dekompressionsunfällen unverändert ohne therapeutische Alternative. Als Behandlungsschema wird grundsätzlich eine HBOT bei 280 kPa empfohlen.

Carbon monoxide (CO) can occur in numerous situations and ambient conditions, such as fire smoke, indoor fireplaces, silos containing large quantities of wood pellets, engine exhaust fumes, and when using hookahs.Symptoms of CO poisoning are nonspecific and can range from dizziness, headache, and angina pectoris to unconsciousness and death.This guideline presents the current state of knowledge and national recommendations on the diagnosis and treatment of patients with CO poisoning.The diagnosis of CO poisoning is based on clinical symptoms and proven or probable exposure to CO. Negative carboxyhemoglobin (COHb) levels should not rule out CO poisoning if the history and symptoms are consistent with this phenomenon. Reduced oxygen-carrying capacity, impairment of the cellular respiratory chain, and immunomodulatory processes may result in myocardial and central nervous tissue damage even after a reduction in COHb.If CO poisoning is suspected, 100% oxygen breathing should be immediately initiated in the prehospital setting.Clinical symptoms do not correlate with COHb elimination from the blood; therefore, COHb monitoring alone is unsuitable for treatment management. Especially in the absence of improvement despite treatment, a reevaluation for other possible differential diagnoses ought to be performed.Evidence regarding the benefit of hyperbaric oxygen therapy (HBOT) is scant and the subject of controversy due to the heterogeneity of studies.If required, HBOT should be initiated within 6 h.All patients with CO poisoning should be informed about the risk of delayed neurological sequelae (DNS)., Kohlenmonoxid (CO) kann in zahlreichen Situationen und Umgebungen auftreten, beispielsweise Brandrauch, Feuerstellen in geschlossenen Räumen, Silos mit großen Mengen an Holzpellets; Motoren-Abgase und der Gebrauch von Wasserpfeifen.Die Symptome einer Kohlenmonoxidvergiftung sind unspezifisch und können Schwindel, Kopfschmerz, Angina pectoris bis zu Bewusstlosigkeit und Tod umfassen.Diese Leitlinie legt den aktuellen Stand der Erkenntnisse und der nationalen Empfehlungen in der Diagnostik und Behandlung von Patienten mit Kohlenmonoxidvergiftungen dar.Die Diagnose einer Kohlenmonoxidvergiftung erfordert klinische Symptome und eine nachgewiesene oder wahrscheinliche Exposition mit Kohlenmonoxid. Ein negativer CO-Hämoglobin (Hb)-Nachweis soll nicht zum Ausschluss einer Kohlenmonoxidvergiftung führen, wenn Anamnese und Symptome übereinstimmend sind. Durch eine reduzierte Sauerstofftransportkapazität, die Beeinträchtigung der zellulären Atmungskette und immunmodulatorische Prozesse kann es auch nach Reduktion des CO-Hb zu myokardialen und zentralnervösen Gewebeschäden kommen.Bei Verdacht auf eine Kohlenmonoxidvergiftung soll präklinisch sofort mit einer 100% Sauerstoffatmung begonnen werden.Die klinische Symptomatik der Patienten korreliert nicht mit der CO-Hb Clearance aus dem Blut. CO-Hb-Kontrollen allein sind für eine Therapiesteuerung ungeeignet. Insbesondere bei fehlender Besserung unter Therapie sollte eine Reevaluation für andere möglicherweise vorliegende Differentialdiagnosen erfolgen.Die Evidenz zum Nutzen der hyperbaren Sauerstofftherapie (HBOT) ist aufgrund der heterogenen Studienlage niedrig und wird kontrovers diskutiert.Der Beginn einer HBOT soll gegebenenfalls innerhalb von 6 Stunden erfolgen.Jeder Patient mit Kohlenmonoxidvergiftung soll über das Risiko eines verzögert einsetzenden neurologischen Defizites (delayed neurological sequelae, DNS), aufgeklärt werden.

Aims: Beat-to-beat variability in cycle length is well-known in atrial fibrillation (Afib); whether this also translates to variability in annulus size remains unknown. Defining annulus maximal size in Afib is critical for accurate selection of percutaneous devices given the frequent association with mitral and tricuspid valve diseases. Methods and results: Images were obtained from 170 patients undergoing 3D echocardiography [100 (50 sinus rhythm (SR) and 50 Afib) for mitral annulus (MA) and 70 (35 SR and 35 Afib) for tricuspid annulus (TA)]. Images were analysed for differences in annular dynamics with a commercially available software. Number of cardiac cycles analysed was 567 in mitral valve and 346 in tricuspid valve. Median absolute difference in maximal MA area over four to six cycles was 1.8 cm2 (range 0.5–5.2 cm2) in Afib vs. 0.8 cm2 (range 0.1–2.9 cm2) in SR, P < 0.001. Maximal MA area was observed within 30–70% of the R-R interval in 81% of cardiac cycles in SR and in 73% of cycles in Afib. Median absolute difference in maximal TA area over four to six cycles was 1.4 cm2 (range 0.5–3.6 cm2) in Afib vs. 0.7 cm2 (range 0.3–1.7 cm2) in SR, P < 0.001. Maximal TA area was observed within 60–100% of the R-R interval in 81% of cardiac cycles in SR, but only in 49% of cycles in Afib. Conclusion: MA and TA reach maximal size within a broad time interval centred around end-systole and end-diastole, respectively, with significant beat-to-beat variability. Afib leads to a larger beat-to-beat variability in both timing of occurrence and values of annulus size than in SR.

Steelmaking is a complex process involving simultaneous multi-phase interactions, chemical reactions, heat transfer and turbulent flow patterns at high temperatures. The severe operating conditions make it difficult to make measurements and directly observe the process. Mathematical modelling has been widely used to evaluate the process and improve understanding of the system and optimise process control. Three approaches to modelling the process, equilibrium modelling to predict the equilibrium chemistry of the process, kinetic modelling to analyse rate of chemical changes throughout the process, and computational fluid modelling to understand the fluid flow in the reactor, are discussed in this paper. The governing equations and the forms of numerical computational solution techniques for these models are described, and critically examined.

Computational Fluid Dynamics was used to model the evaporation of moisture from the walls of a rectangular mine drive. The aim was to test the effectiveness of CFD modelling of mine ventilation when there was simultaneous momentum, heat and mass transfer. The standard differential equations used to describe fluid flow, heat transfer and moisture transport are given, and AVL SWIFT software was used for the CFD modelling. A summary of the results are given., Computational Fluid Dynamics was used to model the evaporation of moisture from the walls of a rectangular mine drive. The aim was to test the effectiveness of CFD modelling of mine ventilation when there was simultaneous momentum, heat and mass transfer. The standard differential equations used to describe fluid flow, heat transfer and moisture transport are given, and AVL SWIFT software was used for the CFD modelling. A summary of the results are given.

Slurry bubble column (SBC) reactors are a modification of bubble column reactors extensively used in industry for numerous physical and chemical applications. Computational fluid dynamic (CFD) has emerged as a promising tool to understand the multiphase flow phenomena inside the SBC. A computational fluid dynamic model has been developed to incorporate pulp and froth zones into one model. In the present research, froth was considered as a separate phase comprised of a mixture of gas, liquid and solids. Considering the froth phase as a separate phase allowed the incorporation of pulp and froth zones into one model by tracking the formation and destruction of the froth phase due to mass exchange between the pulp and froth. Bubble break-up and coalescence were taken into account in the pulp zone, by employing user functions, written in FORTRAN. The effect of bubble coalescence process due to film rupture was considered in the froth phase. The variation in the concentration of attached particles due to attachment and detachment processes were also taken into account. The CFD model predicted the height of froth layer, the concentration of different bubble sizes in both pulp and froth zones, and finally the multiphase flow phenomena in the slurry column. Froth height was found to increase with the increase of gas flow rate while increasing solid concentration decreased froth height., Slurry bubble column (SBC) reactors are a modification of bubble column reactors extensively used in industry for numerous physical and chemical applications. Computational fluid dynamic (CFD) has emerged as a promising tool to understand the multiphase flow phenomena inside the SBC. A computational fluid dynamic model has been developed to incorporate pulp and froth zones into one model. In the present research, froth was considered as a separate phase comprised of a mixture of gas, liquid and solids. Considering the froth phase as a separate phase allowed the incorporation of pulp and froth zones into one model by tracking the formation and destruction of the froth phase due to mass exchange between the pulp and froth. Bubble break-up and coalescence were taken into account in the pulp zone, by employing user functions, written in FORTRAN. The effect of bubble coalescence process due to film rupture was considered in the froth phase. The variation in the concentration of attached particles due to attachment and detachment processes were also taken into account. The CFD model predicted the height of froth layer, the concentration of different bubble sizes in both pulp and froth zones, and finally the multiphase flow phenomena in the slurry column. Froth height was found to increase with the increase of gas flow rate while increasing solid concentration decreased froth height.