[Internal medical emergencies in the pregnant patient : Peripartum sepsis, metabolic derailment, endocrinological emergencies and pulmonary edema]. / Internistische Notfälle bei der schwangeren Patientin : Peripartale Sepsis, Stoffwechselentgleisungen, endokrinologische Notfälle und Lungenödem.

Peripartum emergencies that require intensive medical care represent a major challenge for the interdisciplinary treatment team. Due to physiological changes in pregnant women symptoms can be masked and the initiation of treatment is delayed. Peripartum sepsis has a relatively high incidence. The anti-infective treatment depends on the spectrum of pathogens to be expected. Endocrinological emergencies are rare but can be fulminant and fatal. The development of ketoacidosis is favored by decreased bicarbonate buffer and placental hormones. In the case of thyrotoxicosis, propylthiouracil and thiamazole are available for treatment depending on the stage of gestation. Sheehan's syndrome is an infarction of the anterior lobe of the pituitary gland during a hemorrhage. Due to the loss of production of vital hormones, this can be fatal. The development of pulmonary edema is just as acute. This is favored by physiological changes during pregnancy. The differentiation between hypertensive and hypotensive pulmonary edema is important for the causal treatment.

[Vascular emergencies in pregnant patients : Peripartum hemorrhage, thromboembolic events and hypertensive diseases in pregnancy]. / Vaskuläre Notfälle bei der schwangeren Patientin : Peripartale Hämorrhagie, thrombembolische Ereignisse und hypertensive Schwangerschaftserkrankungen.

In developed countries, peripartum hemorrhage, thromboembolic events and hypertensive pregnancy disorders are the most frequent complications in pregnancy. They pose a significant challenge for the interdisciplinary team of gynecology and anesthesiology. Untreated, these pregnancy-related complications result in a fulminant course. Close consultation between the specialist departments and knowledge of the area of responsibility are essential. In the case of acute bleeding the anesthesiologist is responsible for maintaining adequate circulatory conditions and management of hemostasis. Thromboembolic events require immediate anticoagulation and focused diagnostics. Thereby, both the fetal and the maternal risks must be weighed up. The hypertensive diseases in pregnancy have a very high risk of complications. In addition to symptomatic treatment in the intensive care unit, the optimal time of delivery must be determined by an interdisciplinary consensus. This is the only causal treatment option possible.

[Internal medical emergencies in the pregnant patient : Peripartum sepsis, metabolic derailment, endocrinological emergencies and pulmonary edema]. / Internistische Notfälle bei der schwangeren Patientin : Peripartale Sepsis, Stoffwechselentgleisungen, endokrinologische Notfälle und Lungenödem.

Peripartum emergencies that require intensive medical care represent a major challenge for the interdisciplinary treatment team. Due to physiological changes in pregnant women symptoms can be masked and the initiation of treatment is delayed. Peripartum sepsis has a relatively high incidence. The anti-infective treatment depends on the spectrum of pathogens to be expected. Endocrinological emergencies are rare but can be fulminant and fatal. The development of ketoacidosis is favored by decreased bicarbonate buffer and placental hormones. In the case of thyrotoxicosis, propylthiouracil and thiamazole are available for treatment depending on the stage of gestation. Sheehan's syndrome is an infarction of the anterior lobe of the pituitary gland during a hemorrhage. Due to the loss of production of vital hormones, this can be fatal. The development of pulmonary edema is just as acute. This is favored by physiological changes during pregnancy. The differentiation between hypertensive and hypotensive pulmonary edema is important for the causal treatment.

[Peripheral truncal blocks-Overview and assessment]. / Periphere Rumpfwandblockaden ­ Übersicht und Bewertung.

By implementation of sonography for regional anesthesia, truncal blocks became more relevant in the daily practice of anesthesia and pain therapy. Due to visualized needle guidance ultrasound supports more safety and helps to avoid complications during needle placement. Additionally, complex punctures are possible that were associated with higher risk using landmarks alone. Next to the blocking of specific nerve structures, interfascial and compartment blocks have also become established, whereby the visualization of individual nerves and plexus structures is not of relevance. The present review article describes published and clinically established puncture techniques with respect to the indications and procedures. The clinical value is reported according to the scientific evidence and the analgesic profile. Moreover, the authors explain potential risks, complications and dosing of local anesthetic agents.

Intraneural injection of a test dose of local anesthetic in peripheral nerves - does it induce histological changes in nerve tissue?

BACKGROUND & OBJECTIVES: Most anesthesiologists use the injection of a test dose of local anesthetic in order to evaluate the final needle tip position. Thus, the intraneural injection of a full dose can be avoided. The aim of this study was to analyze whether an intraneural injection of a test dose of bupivacaine could trigger histological changes. METHODS: Intraneural injections under direct vision were performed in 40 brachial plexus nerves in seven anesthetized pigs. Tibial nerves served as positive and negative controls. Two milliliter of bupivacaine 0.5% was injected in three nerves on the left brachial plexus. For control of local anesthetic's toxicity Ringer's solution was applied intraneurally on the right side. After maintaining 48 h of general anesthesia, the nerves were resected. The specimens were processed for histological examination and assessed for inflammation (hematoxylin and eosin stain, CD68-immunohistochemistry) and myelin damage (Kluver-Barrera stain). The degree of nerve injury was rated on a scale from 0 (no injury) to 4 (severe injury). RESULTS: Statistical analysis showed no significant differences between the bupivacaine group [median (interquartile range) 1 (1-1.5)] and the Ringer's solution group [1 (0.5-2) P = 0.772]. Mild myelin alteration was found in 12.5% of all specimens following intraneural injection, irrespective of the applied substance. CONCLUSIONS: "In our experimental study, intraneural injection of 2 ml of bupivacaine or Ringer's solution showed comparable mild inflammation. Nevertheless, inflammation can only be prevented by strictly avoiding nerve perforation followed by intraneural injection, as mechanical nerve perforation is a key factor for evolving inflammation.

[Dexmedetomidine in the treatment of acute alcohol withdrawal delirium]. / Dexmedetomidin in der Therapie des akuten Alkoholentzugsdelirs.

Alcohol withdrawal syndrome has a high clinical prevalence. Severe cases must be treated in an intensive care unit and are associated with a high mortality rate, depending on patient comorbidities. Clinical requirements include sedation, control of vegetative symptoms, treatment of hallucinations and, when necessary, anticonvulsive therapy. Currently, there is no single substance that fulfills these requirements. National and international guidelines recommend a combination of various substances. The central α2-adrenergic receptor agonist clonidine is used as a therapeutic adjuvant. In consideration of its pharmacological characteristics, dexmedetomidine is assumed to be more advantageous compared to clondine. Case studies with dexmedetomidine in alcohol withdrawal syndrome show the safety of its application and a benzodiazepine-sparing effect. Its incorporation in escalating intensive care therapy of severe cases could be appropriate.

[Anesthesia in obstetrics: Tried and trusted methods, current standards and new challenges]. / Anästhesie in der Geburtshilfe: Altbewährtes, gegenwärtige Standards und neue Herausforderungen.

Obstetric analgesia and anesthesia have some specific aspects, which in particular are directly related to pathophysiological alterations during pregnancy and also to the circumstance that two or even more individuals are always affected by complications or therapeutic measures. This review article deals with some evergreens and hot topics of obstetric anesthesia and essential new knowledge on these aspects is described. The article summarizes the talks given at the 16th symposium on obstetric anesthesia organized by the Scientific Committee for Regional Anaesthesia and Obstetric Anaesthesia within the German Society of Anaesthesiology. The topics are in particular, special features and pitfalls of informed consent in the delivery room, challenges in education and training in obstetric anesthesia, expedient inclusion of simulation-assisted training and further education on risk minimization, knowledge and recommendations on fasting for the delivery room and cesarean sections, monitoring in obstetric anesthesia by neuraxial and alternative procedures, the possibilities and limitations of using ultrasound for lumbal epidural catheter positioning in the delivery room, recommended approaches in preparing peridural catheters for cesarean section, basic principles of cardiotocography, postoperative analgesia after cesarean section, the practice of early bonding in the delivery room during cesarean section births and the management of postpartum hemorrhage.

[Improvement of sonographic visualization of cannula needle tips by alignment of the needle lumen : In vitro investigation of established needle tip forms]. / Verbesserung der sonographischen Sichtbarkeit von Kanülenspitzen durch Ausrichtung der Öffnungsfläche : In-vitro-Untersuchung etablierter Schliffformen.

BACKGROUND: In the context of ultrasound-guided peripheral nerve blocks (regional anesthesia), clear visualization of the needle tip and the target structure are mandatory for the performance of a safe puncture and injection. The purpose of this in vitro study was to analyze the visualization of different forms of needle tips and calibers of cannulas in a phantom simulating human tissue, with the help of a standardized image analysis system. Different depths and angles of the puncture needle in relation to the ultrasound probe were tested. MATERIAL AND METHODS: Cannula needles established for use in regional anesthesia with different surfaces, diameters and needle tip form in 23 different combinations were analyzed. A gelatine-based phantom was used to simulate human tissue. The standardized visualization of the needle tip with the ultrasound probe was performed in plane at different angles (30°, 45° and 60°), depths of penetration (1 cm, 2 cm and 3 cm) and two different alignments of the cannula needle lumen to the ultrasound probe (0° and 180°). The screenshots of the ultrasound pictures were analyzed by quantifying the pixel brightness around the needle tip (region of interest) with a standardized software (score 0-255). RESULTS: In this study 1104 ultrasound images of cannula needles were analyzed. Diminished scores (reduced pixel brightness) of the needle tips were documented with increasing distance from the ultrasound probe. Comparison of punctures at angles of 30° and 45° showed no differences in needle tip visibility (same scores) but punctures at an angle of 60° were poorly visualized compared with 30° and 45° (mean scores 87.90 ± 11.60 vs. 78.40 ± 12.07, p < 0.001 and 81.85 ± 11.79 vs. 78.40 ± 12.07, p < 0.001, respectively). The direct alignment of the cannula lumen towards the ultrasound probe (0°) was significantly more easily visualized when compared with the reverse alignment of 180° (mean scores 86.90 ± 12.74 vs. 84.80 ± 11.66, p = 0.003, respectively). No differences in visibility were detected between the different cannula needle diameters examined. The Sprotte cannula showed the best visibility score with respect to the cut of the needle tip (mean score 89.40 ± 11.72). CONCLUSION: The visibility of cannulas in ultrasound scans depends on the ultrasound frequency, angle of the puncture in relation to the ultrasound probe and the depth of penetration. The results of this study showed that direct alignment of the cannula needle lumen towards the ultrasound probe (0°) independently improved needle tip visualization. This simple measure allows a significant improvement in the safe performance of ultrasound-guided peripheral nerve blocks.

Peripheral nerve blocks on the upper extremity: Technique of landmark-based and ultrasound-guided approaches.

The German Society of Anaesthesiology and Intensive Care Medicine (Deutsche Gesellschaft für Anästhesiologie und Intensivmedizin, DGAI) established an expert panel to develop preliminary recommendations for the application of peripheral nerve blocks on the upper extremity. The present recommendations state in different variations how ultrasound and/or electrical nerve stimulation guided nerve blocks should be performed. The description of each procedure is rather a recommendation than a guideline. The anaesthesiologist should select the variation of block which provides the highest grade of safety according to his individual opportunities. The first section comprises recommendations regarding dosages of local anaesthetics, general indications and contraindications for peripheral nerve blocks and informations about complications. In the following sections most common blocks techniques on the upper extremity are described.

[Post-mortem organ donation]. / Postmortale Organspende.

In Germany approximately 3000 body organs are transplanted annually. In general, all artificially ventilated patients with diagnosed brain death are potential organ donors. All German hospitals are obliged to report potential organ donors and be actively involved in the organ donation process. These matters lie under the jurisdiction of the German transplantation act. An essential prerequisite for organ donation is the diagnosis of brain death according to the guidelines of the German Medical Association. Brain death is associated with complex pathophysiological changes in cardiopulmonary function as well as fluid, electrolyte and metabolic homeostasis. In the case of diagnosed brain death and with permission for organ donation, a precise organ-protective therapy is initiated, essentially focussing on optimal organ perfusion and oxygenation. The quality of organ protection has a direct influence on the outcome of transplantation.

[Seeing more : Technical innovations in regional anesthesia]. / Mehr sehen : Technische Innovationen in der Regionalanästhesie.

Visualization and verification are key factors since the implementation of ultrasound-guided regional anesthesia. This article reviews and discusses newer technical innovations in regional anesthesia with regard to optimization of needle guidance, improvements in needle visibility, technical improvements in ultrasound techniques and innovative technologies in regional anesthesia. Clinically available applications are presented as well as experimental tools and techniques with a potential for clinical implementation in the future. Mechanical needle guides are used to improve alignment of needle axis and ultrasound beam axis. Compound imaging technology improves needle visibility in steep needle insertion angles and is already implemented in daily clinical practice. Sonoelastography improves tissue discrimination and detection of small amounts of fluids. Benefits of 3D and 4D ultrasound in regional anesthesia are discussed as well as experimental tools for tissue discrimination, such as optical reflection spectrophotometry.

Nerve localization for peripheral regional anesthesia. Recommendations of the German Society of Anaesthesiology and Intensive Care Medicine.

The German Society of Anaesthesiology and Intensive Care Medicine (Deutsche Gesellschaft für Anästhesiologie und Intensivmedizin, DGAI) established an expert panel to develop preliminary recommendations for nerve localization in peripheral regional anesthesia. Based on expert knowledge and the relatively limited data, the recommendations state how ultrasound and/or electrical nerve stimulation should be used in daily practice, and where and when local anesthetics should be injected. Moreover, it was defined under which conditions a peripheral nerve block under general anesthesia or deep sedation is applicable.Regarding the use of ultrasound the expert opinion was that out-of-plane and in-plane-techniques can be considered equal with respect to patient safety. Nevertheless, the direct or indirect visualization of the needle tip has to be assured. The injection of local anesthetics has to be visualized. Injections into nerves or those requiring an injection pressure should be avoided. The sole use of electrical nerve stimulation or ultrasound for nerve localization is still a suitable option as well as their combined use. To avoid accidental intraneural needle placement, an electrical current threshold ≥ 0.5 mA should be used. Moreover, it was stated that peripheral nerve blocks or continuous nerve block techniques under sedation or general anesthesia are applicable in adult patients who are unable to tolerate the block being performed in an awake state or have difficulty cooperating.This article is published in English.

[Guidance of axillary multiple injection technique for plexus anesthesia. Ultrasound versus nerve stimulation]. / Steuerung der axillären Multiinjektionstechnik zur Plexusanästhesie. Ultraschall vs. Nervenstimulation.

BACKGROUND: Ultrasound guidance is still a young method in regional anesthesia when compared to nerve stimulation and only a few studies exist comparing these two techniques in an axillary multiple injection approach. AIM: This prospective, randomized, observer-blinded study compared an ultrasound-guided (SONO) quadruple injection axillary block (out of plane, perineural) with a nerve stimulation-guided (STIM) triple injection axillary block for upper limb surgery. MATERIAL AND METHODS: A total of 60 patients were randomized to either the SONO (n = 30) or STIM (n = 30) group. For the block 40-50 ml mepivacaine 1.5 % (plexus) and 5-10 ml mepivacaine 0.5 % (subcutaneous in the medial skin of the arm) was used. Anesthesia time was recorded as the primary end point. After evaluation of block-related pain using a visual analog scale (VAS) a blinded observer tested sensory and motor function of the median nerve (MED), ulnar nerve (ULN), radial nerve (RAD), musculocutaneous nerve of the upper limb (MUC) and medial cutaneous nerve of the forearm (CAM) at defined times. The main outcome variable was onset time (defined loss of sensory/motor function). RESULTS: No differences were observed between the groups in terms of onset time (single nerves 10-20 min, plexus 20-25 min) and success rate (SONO 90 %, STIM 89 %). Patient satisfaction as measured by block-related pain score (VAS 2 cm), complications (vascular puncture SONO 7 %, STIM 11 %; paresthesia SONO 21 %, STIM 22 %) and patient acceptance (SONO 92 %, STIM 91 %) showed no differences. Performance time was shorter in the SONO group (6.68 ± 1.72 min vs. 8.05 ± 2.58, p = 0.02). CONCLUSION: Nerve stimulation-guided axillary plexus blocks performed by trained anesthesiologists may result in similar onset times and success rates compared to ultrasound-guided blocks.

[Localization of peripheral nerves. Success and safety with electrical nerve stimulation]. / Lokalisation peripherer Nerven. Erfolg und Sicherheit mit elektrischer Nervenstimulation.

Peripheral electrical nerve stimulation is one of the standard applications in peripheral regional anesthesia in addition to the ultrasound technique. Among other findings, the visualization of needle and nerve during ultrasound-guided blockade caused a change in clinical practice of peripheral nerve stimulation in the last decade. In the present article old and new aspects of principles and clinical practice of the nerve stimulation technique are presented and summarized in a total clinical concept in order to achieve safe and successful peripheral regional anesthesia using electrical peripheral nerve stimulation.

[Dexmedetomidine]. / Dexmedetomidin.

Dexmedetomidine is a highly selective α2-receptor agonist with sedative, analgetic and anxiolytic effects. It is chemically related to clonidine and has been an authorized drug in Europe since September 2011. Dexmedetomidine enables a level of sedation in which mechanically ventilated patients may be woken by verbal stimulation (Richmond agitation sedation scale RASS 0--3). In this respect dexmedetomidine achieves the same desired effect as propofol and midazolam; however, in direct comparison to a sedation regime with benzodiazepines, dexmedetomidine reduces the prevalence, duration and severity of delirium in intensive care. Patients sedated by dexmedetomidine can statistically be extubated earlier and an influence on duration of stay in the intensive care unit (ICU) has not been shown. Daily therapy costs are approximately 5 times higher than those of propofol but an objective standpoint in relation to clinical cost efficiency is unattainable.

[Peripheral regional anesthesia in patients under general anesthesia: risk assessment with respect to parasthesia, injection pain and nerve damage]. / Periphere Regionalanästhesie beim Patienten in Allgemeinanästhesie : Risikobewertung bezüglich Parästhesie, Injektionsschmerz und Nervenschäden.

Nerve injury after peripheral regional anesthesia is rare and is not usually permanent. Some authors believe that inducing peripheral nerve blocks in patients during general anesthesia or analgosedation adds an additional risk factor for neuronal damage. This is based on published case reports showing that there is a positive correlation between paresthesia experienced during regional anesthesia and subsequent nerve injury. Therefore, many sources recommend that regional nerve blocks should only be performed in awake or lightly sedated patients, at least in adults. However, there is no scientific basis for this recommendation. Furthermore, there is no proof that regional anesthesia performed in patients under general anesthesia or deep sedation bears a greater risk than in awake or lightly sedated patients. Currently anesthesiologists are free to follow personal preferences in this matter as there is no good evidence favoring one approach over the other. The risk of systemic toxicity of local anesthetic agents is not higher in patients who receive regional anesthesia under general anesthesia or deep sedation. Finally, in children and uncooperative adults the administration of peripheral nerve blocks under general anesthesia or deep sedation is widely accepted.