[Intraoperative transesophageal echocardiography for emergency diagnostics in noncardiac surgery patients]. / Intraoperative transösophageale Echokardiographie als Notfalldiagnostik bei nichtkardiochirurgischen Patienten.

Due to the development of compact and mobile devices, transesophageal echocardiography (TEE) is now being used as one important point-of-care diagnostic method in emergency rooms, intensive care units and operating rooms. In the first part of this advanced training series, general aspects of the examination method and the procedure as well as indications and contraindications were outlined. In addition, an overview of application areas beyond cardiac surgery in which TEE can be used to monitor the patient or to assist with the operative procedure was provided. In the second part, the main findings during intraoperative TEE in the event of hemodynamic instability or unexplained hypoxemia are presented. A shortened emergency examination as proposed by Reeves et al. is outlined. The article concludes with an outlook on semiautomatic interpretation software and computer-aided image acquisition.

[Intraoperative transesophageal echocardiography as monitoring procedure in noncardiac surgery patients]. / Intraoperative transösophageale Echokardiographie als Monitoring-Verfahren bei nichtkardiochirurgischen Patienten.

Transesophageal echocardiography (TEE) is firmly established in cardiac surgery for diagnostics, hemodynamic monitoring and as a guiding tool. Dynamic and (patho)physiological processes of the heart can be immediately depicted. Ideally, therapeutic changes can be derived. For this reason, TEE is increasingly used in high-risk non-cardiac surgery interventions and in the interventional setting. In the first part of this advanced training series, general aspects regarding TEE examinations as well as indications and contraindications are presented. Clinical fields of application, where TEE can play a role in hemodynamic monitoring are outlined. The second part focusses on an emergency examination pathway and differential diagnoses, which can be made in the event of intraoperative hemodynamic instability or unexplained hypoxemia using TEE. The article concludes with an outlook on the use of computer-aided evaluation of TEE images.

[Near-infrared spectroscopy : Technique, development, current use and perspectives]. / Nahinfrarotspektroskopie : Technik, Entwicklung, aktueller Einsatz und Ausblick.

Near-infrared spectroscopy (NIRS) has been available in research and clinical practice for more than four decades. Recently, there have been numerous publications and substantial developments in the field. This article describes the clinical application of NIRS in relation to current guidelines, with a focus on pediatric and cardiac anesthesia. It discusses technical and physiological principles, pitfalls in clinical use and presents (patho)physiological influencing factors and derived variables, such as fractional oxygen extraction (FOE) and the cerebral oxygen index (COx). Recommendations for the interpretation of NIRS values in connection with influencing factors, such as oxygen transport capacity, gas exchange and circulation as well as an algorithm for cardiac anesthesia are presented. Limitations of the method and the lack of comparability of values from different devices as well as generally accepted standard values are explained. Technical differences and advantages compared to pulse oxymetry and transcranial Doppler sonography are illuminated. Finally, the prognostic significance and requirements for future clinical studies are discussed.

[Drugs for intravenous induction of anesthesia: ketamine, midazolam and synopsis of current hypnotics]. / Medikamente zur intravenösen Narkoseinduktion: Ketamin, Midazolam und Synopsis der gängigen Hypnotika.

Ketamine and midazolam form the endpoint of a series of articles about intravenous induction of anesthesia . Both substances can be used as single induction hypnotic drugs; however, in practice, this is unusual. Both substances, with the exception of a few very specific indications and clinical situations, are more frequently used in combination or with one of the more common alternatives propofol, barbiturates and etomidate. The reasons are the activity and side effects of both substances and their positive characteristics are used more as a supplement. In the concluding comparison the five discussed induction hypnotics are judged against each other. The use in certain clinical constellations and in special patient populations is evaluated individually for each substance. It is highlighted which drug appears most appropriate in which situation. As methohexital is nowadays only administered in very few clinical situations, this substance is not included in the comparative assessment.

[Drugs for intravenous induction of anesthesia: barbiturates]. / Medikamente zur intravenösen Narkoseinduktion: Barbiturate.

The discovery of barbituric acid and research on its derivatives have long been of importance in advancements in modern anesthesia. Decades of clinical use of barbiturates worldwide and their abuse has led to an enormous amount of knowledge. Thiopental and methohexital are ultra-short acting derivatives of barbiturates. Their clinical application has been accompanied by an enormous increase in the knowledge of the pharmacology of cerebrally active drugs, in particular gamma-aminobutyric acid (GABAA) receptor and GABA-induced effects on nerve cell membranes. Despite the development of newer substances, thiopental still has a firm place in clinical applications. Currently it is mainly used in obstetrics for induction of cesarean sections under general anesthesia. A disadvantage, when properly used to induce anesthesia, is usually only the prolonged elimination kinetics of barbiturates. It is beneficial that barbiturates do not require side effect provoking solubilizers.

[Drugs for intravenous induction of anesthesia: propofol]. / Medikamente zur intravenösen Narkoseinduktion: Propofol.

In a series of articles dealing with hypnotics for induction of anesthesia, this article describes the development and current value of propofol. Its significance far exceeds that of a pure induction hypnotic (sedation in diagnostic and therapeutic procedures and on the intensive care unit). Propofol is also used for sedation in diagnostic and therapeutic procedures and on the intensive care unit. In the field of induction of anesthesia, the alternatives are barely used. Some contraindications are still controversial whereas others are no longer sufficiently anchored in the users' awareness (widespread off-label use). Adverse effects, such as injection pain, infection risk and propofol-related infusion syndrome (PRIS) could be significantly reduced by pharmacovigilance. With appropriate caution nearly the whole spectrum of anesthesiology patients can be treated using propofol. The hemodynamic side effects and the rare but potentially fatal PRIS are limitations. Further developments address the water solubility and the solubilizing agents of propofol.

[Etomidate for intravenous induction of anaesthesia]. / Medikamente zur intravenösen Narkoseinduktion: Etomidat.

The pharmacological and historical knowledge about the currently available intravenous induction hypnotics form the basis for the daily work of anesthetists. Side effects of using hypnotic induction agents must be anticipated and adequately treated. Decades of experience with using intravenous induction hypnotics have led to theoretical requirements for an ideal narcotic agent with a best possible side effect profile. In the absence of this optimal hypnotic induction agent, a careful selection of one or a combination of narcotic drugs is necessary to meet the needs of the respective risk constellation of the patient. While propofol enjoyed increasing frequency of use over the last three decades and is currently regarded as the gold standard in numerous clinics, thiopental is a noteworthy alternative apart from its elimination kinetics. Furthermore, substances with favorable hemodynamic profiles are available with etomidate and ketamine. Midazolam as a short-acting benzodiazepine rounds off the spectrum.

[Perioperative coagulation management during ascending aorta replacement on apixaban]. / Perioperatives Gerinnungsmanagement bei Ersatz der Aorta ascendens unter Apixaban.

The direct oral anticoagulants (DOACs) present a valid therapeutic alternative to vitamin K antagonists in patients with non-valvular atrial fibrillation, for the prevention of venous thromboembolism, and for the treatment and prevention of the recurrence of pulmonary embolisms and deep vein thrombosis. Despite Idarucizumab as an antagonist of Dabigatran there are no other specific antidotes available yet. Therefore, perioperative coagulation management by DOACs is challenging in patients undergoing emergency surgical procedures with a high risk of bleeding complications. This case study describes the perioperative procedure during ascending aorta replacement after aortic dissection with apixaban administration.