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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.

Background Dislocation of catheters within the tissue is a challenge in continuous regional anesthesia. A novel self-coiling catheter design is available and has demonstrated a lower dislocation rate in a cadaver model. The dislocation rate and effect on postoperative pain of these catheters in vivo has yet to be determined and were the subjects of this investigation. Methods After ethics committee approval 140 patients undergoing elective distal lower limb surgery were enrolled in this prospective randomized controlled trial. Preoperatively, patients were randomly assigned and received either the conventional (n = 70) or self-coiling catheter (n = 70) for ultrasound-guided popliteal sciatic nerve block in short axis view and by the in-plane approach from lateral to medial. The primary outcome was pain intensity after surgery and on the following three postoperative days. Secondary outcomes investigated were dislocation rate in situ determined by sonography, catheter movement visible from outside, opioid consumption as well as leakage at the puncture site. Results All catheters were successfully inserted. The study population of self-coiling catheters had significantly lower mean numeric rating scale values than the reference cohort on the first (p = 0.01) and second postoperative days (p p = 0.04, p = 0.03 and p = 0.04, respectively). Conclusion The self-coiling catheter offers a better postoperative pain control and a lower dislocation rate within the tissue when blocking the popliteal sciatic nerve compared to a conventional catheter. Further trials in large patient cohorts are warranted to investigate the potential beneficial effects of self-coiling catheters for other localisations and other application techniques. Trial registration The trial was registered at German Clinical Trials Register (DRKS) on 08/04/2020 (DRKS00020938, retrospectively registered).

BackgroundProlonged catheter use is controversial because of the risk of catheter-related infection, but the extent to which the risk increases over time remains unknown. We thus assessed the time-dependence of catheter-related infection risk up to 15 days.MethodsOur analysis was based on the German Network for Regional Anesthesia, which includes 25 centers. We considered 44,555 patients who had surgery between 2007 and 2014 and had continuous regional anesthesia as well as complete covariable details. Cox regression analysis was performed and adjusted for confounding covariables to examine the relationship between catheter duration and probability of infection-free catheter use.ResultsAfter adjustment for confounding factors, the probability of infection-free catheter use decreases with each day of peripheral and epidural catheter use. In peripheral catheters, it was 99% at day 4 of catheter duration, 96% at day 7, and 73% at day 15. In epidural catheters, it was 99% at day 4 of catheter duration, 95% at day 7, and 73% at day 15. Only 31 patients (0.07%) had severe infections that prompted surgical intervention. Among these were five catheters that initially had only mild or moderate signs of infection and were left in situ; all progressed to severe infections.ConclusionsInfection risk in catheter use increases over time, especially after four days. Infected catheters should be removed as soon as practical.

Die ultraschallgesteuerte distale Ischiadikusblockade (DIB) auf Hohe der Bifurkation hat eine hohe Erfolgsrate bei schneller Anschlagzeit. Die sichere Durchfuhrung kann hier fur Unerfahrene allerdings schwierig sein. Wenig distal der Bifurkation sind die abzweigenden N. peroneus communis (NPC) und N. tibialis (NT) aber bereits deutlich voneinander getrennt darstellbar. Wir untersuchten, ob hier, verglichen mit der Blockade proximal der Bifurkation, eine ebenburtige Qualitat erreicht werden kann bei jedoch potenziell geringerer Gefahr von Nervenschaden. Je 56 Patienten erhielten prospektiv randomisiert eine DIB distal der Bifurkation „out-of-plane“ (dist.) bzw. proximal der Bifurkation „in-plane“ (prox.) mit 30 ml Mepivacain 1 %. Nach 15 und 30 min wurde der Erfolg (NT und NPC: sensorische und motorische Blockade: 0 = keine bis max. 2 = vollstandig, Veranderung der Hauttemperatur) untersucherverblindet gepruft. Videosequenzen der Blockaden wurden retrospektiv bezuglich Ausbreitung des Lokalanasthetikums und akzidentieller intraneuraler Injektionen von einem unabhangigen Experten gesichtet. Addierte Einzelmessungen und Temperaturverlauf zeigen bei vergleichbarer Anlagedauer eine signifikant kurzere Anschlagszeit und bessere Wirkung (dist/prox: 15 min: 3,13 ± 1,86/1,82 ± 1,62; 30 min: 5,73 ± 1,92/3,21 ± 1,88; T15 min: 30,3 ± 3,48/28,0 ± 3,67, T30 min. 33,0 ± 2,46/30,6 ± 3,86; Mittelwert/Standardabweichung; ANOVA; p jeweils

Dural puncture, paraesthesia and vascular puncture are the most common complications of epidural catheter insertion. Their association with variation in midline needle insertion depth is unknown. This study evaluated the risk of dural and vascular punctures and the unwanted events paraesthesia and multiple skin punctures related to midline needle insertion depth. A total of 14,503 epidural catheter insertions including lumbar (L1–L5; n = 5367), low thoracic (T7–T12, n = 8234) and upper thoracic (T1–T6, n = 902) insertions, were extracted from the German Network for Regional Anaesthesia registry between 2007 and 2015. The primary outcomes were compared with logistic regression and adjusted (adj) for confounders to determine the risk of complications/events. Results are presented as odds ratios (OR, [95% confidence interval]). Midline insertion depth depended on body mass index, sex, and spinal level. After adjusting for confounders increased puncture depth (cm) remained an independent risk factor for vascular puncture (adjOR 1.27 [1.09–1.47], p = 0.002) and multiple skin punctures (adjOR 1.25 [1.21–1.29], p

BACKGROUND Ultrasound, nerve stimulation, and their combination are all considered acceptable ways to guide peripheral nerve blocks. Which approach is most effective and associated with the fewest complications is unknown. We therefore used a large registry to analyze whether there are differences in vascular punctures, multiple skin punctures, and unintended paresthesia. METHODS Twenty-six thousand seven hundred and thirty-three cases were extracted from the 25-center German Network for Regional Anesthesia registry between 2007 and 2016 and grouped into ultrasound-guided puncture (n = 10,380), ultrasound combined with nerve stimulation (n=8173), and nerve stimulation alone (n = 8180). The primary outcomes of vascular puncture, multiple skin punctures, and unintended paresthesia during insertion were compared with conditional logistic regression after 1:1:1 propensity score matching. Results are presented as odds ratios and 95% CIs. RESULTS Propensity matching successfully paired 2508 patients with ultrasound alone (24% of 10,380 patients), 2508 patients with a combination of ultrasound/nerve stimulation (31% of 8173 patients), and 2508 patients with nerve stimulation alone (31% of 8180 patients). After matching, no variable was imbalanced (standardized differences

Background Large amounts of local anaesthetics (LA) are used during psoas compartment block (PCB), especially if combined with sciatic nerve block. Data regarding early pharmacokinetics of ropivacaine for PCB are lacking, notably when a vasoconstrictive agent has not been added. Methods PCB was established in 11 patients using 150 mg ropivacaine without epinephrine. Free and total arterial plasma concentrations of ropivacaine were measured at nine time points during the following 30 min. Also total protein, albumin, and α1-acid glycoprotein concentrations were analysed. Results Ropivacaine plasma concentrations were found in all patients within 30 s after injections. Maximum measured plasma concentrations were measured in all but two patients within the first 10 min. One patient experienced partial intravascular injection. Plasma concentrations showed wide inter-individual variability. Ranges of maximum measured plasma concentrations of total and free ropivacaine were 422–3905 and 5–186 ng ml−1, respectively. The Pearson correlation between total and free concentrations was 0.96. No obvious relationship between concentrations of different plasma proteins (total protein, albumin, α1-acid glycoprotein) and ropivacaine concentrations was found. Maximal 5% of the measured ropivacaine was unbound. All blocks were successful and no signs of toxicity were observed. Conclusions Maximum measured plasma concentrations of ropivacaine after PCB must be expected within 10 min. Although plasma concentrations stayed below toxic thresholds, our study demonstrates the risk of this regional anaesthesia technique. Clinical trial registration The clinical study was not registered because enrolment of study patients occurred in 2006.

Psoas blocks are an alternative to femoral nerve blocks and have the potential advantage of blocking the entire lumbar plexus. However, the psoas muscle is located deeply, making psoas blocks more difficult than femoral blocks. In contrast, while femoral blocks are generally easy to perform, the inguinal region is prone to infection. We thus tested the hypothesis that psoas blocks are associated with more insertion-related complications than femoral blocks but have fewer catheter-related infections.We extracted 22,434 surgical cases from the German Network for Regional Anesthesia registry (2007-2014) and grouped cases as psoas (n = 7593) and femoral (n = 14,841) blocks. Insertion-related complications (including single-shot blocks and catheter) and infectious complications (including only catheter) in each group were compared with χ tests. The groups were compared with multivariable logistic models, adjusted for potential confounding factors.After adjustment for potential confounding factors, psoas blocks were associated with more complications than femoral blocks including vascular puncture 6.3% versus 1.1%, with an adjusted odds ratio (aOR) of 3.6 (95% confidence interval [CI], 2.9-4.6; P0.001), and multiple skin punctures 12.6% versus 7.7%, with an aOR of 2.6 (95% CI, 2.1-3.3; P0.001). Psoas blocks were also associated with fewer catheter-related infections: 0.3% versus 0.9% (aOR of 0.4; 95% CI, 0.2-0.8; P = 0.016), and with improved patient satisfaction (mean ± SD 0- to 10-point scale score, 9.6 ± 1.2 vs 8.4 ± 2.9; P0.001). Results from a propensity-matched sensitivity analysis were similar.Psoas blocks are associated with more insertion-related complications but fewer infectious complications.ID NCT02846610.

The German Society of Anaesthesiology and Intensive Care Medicine (Deutsche Gesellschaft fur Anasthesiologie 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.

The German Society of Anaesthesiology and Intensive Care Medicine (Deutsche Gesellschaft fur Anasthesiologie 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.

Fragestellung Die Inhalation von Perfluorhexan (PFH) fuhrt im Olsaure-induzierten Lungenversagen am Schaf zu einer Verbesserung der Oxygenierung und der mechanischen Lungenfunktion. Ziel der Untersuchung war es, Effekte von PFH bei der Therapie eines experimentellen „acute respiratory distress syndrome“ (ARDS) uber einen langeren Beobachtungszeitraum (4 h) zu untersuchen sowie die Moglichkeit einer schrittweisen Reduktion der inspiratorischen Sauerstofffraktion (FIO2) in der Behandlungsgruppe zu evaluieren.

Im Rahmen von Spinalanasthesien (SPA) kann die Ausbreitung der sensorischen und sympathischen Blockade durch Lagewechsel sowohl nach der Anwendung von isobaren wie auch hyperbaren Lokalanasthetika (LA) unvorhersehbar zunehmen. Wir berichten in diesem Zusammenhang uber einen 50-jahrigen adiposen Patienten, bei dem zur Versorgung einer Unterschenkelfraktur eine SPA mit 17,5 mg 0,5%igem isobarem Bupivacain durchgefuhrt wurde. Nach 15 min erreichte die Ausbreitung der sensorischen Blockade ihr Maximum bei Th8. Nach 15° Oberkorperhochlagerung, 35 min nach der intrathekalen Injektion des LA, kam es innerhalb der nachsten 10 min zu einer unbeabsichtigten Zunahme der kranialen Ausbreitung um 10 Segmente bis C6. Der Patient wurde bradykard, hypoton, respiratorisch insuffizient und musste intubiert und beatmet werden. Die Hamodynamik wurde durch die intravenose Applikation von Akrinor®, Atropin und kolloidalen Volumenersatzmitteln rasch stabilisiert. Die anschliesende Operation erfolgte ohne Besonderheiten in Intubationsnarkose. Bei Operationsende wurde der Patient bei stabiler Hamodynamik und suffizienter Spontanatmung problemlos extubiert. Unmittelbar nach Extubation erreichte die kraniale sensorische Ausbreitung L2. Die Kasuistik zeigt, dass es auch nach vermeintlicher Fixierung des LA zu einer unerwarteten Zunahme der Blockade nach Lagewechsel kommen kann, und dass Patienten nach SPA bis zur Remission der Blockade sorgfaltig uberwacht werden mussen. Die der unbeabsichtigten kranialen Ausbreitung von sensorischer und sympathischer Blockade zugrunde liegenden Pathomechanismen werden diskutiert.

BackgroundTo analyze safety issues of regional anaesthesia and analgesia in Germany only a few single center studies are available. Therefore, the German Society for Anaesthesiology and Intensive Care Medicine (Deutschen Gesellschaft fur Anasthesiologie und Intensivmedizin, DGAI) and the Professional Association of German Anaesthetists (Berufsverband Deutscher Anasthesisten, BDA) initiated a network for safety in regional anaesthesia. From this the first results on infectious complications will be reported.Materials and methodsIn a Delphi process the documentation of the setup and maintenance of regional anaesthesia and analgesia was agreed with the participants in a working group from the DGAI. After approval by the officially authorized representative for patient data privacy protection a registry was programmed to collect anonymous data. Up to October 2008 data from 6 centers could be analyzed.ResultsAfter testing for plausibility 8,781 regional anaesthesia procedures (22,112 catheter days) could be analyzed. The 5,057 neuraxial and 3,724 peripheral catheter-based procedures were in place for a median of 2.48 days (range 1.0-3.0 days) and 4 severe, 15 moderate and 128 mild infections were recorded. Diabetics were not found to show a statistically significant increase in risk (2.6% compared to 1.9% for non-diabetics: n.s.). Neuraxial procedures seem to have a higher rate of infections than peripheral procedures (2.7% vs. 1.3%, p

Regional anaesthesia generally is considered to be safe. However, reports of complications with different severities are also well known. The scientific working group of regional anaesthesia of the DGAI has founded a network in conjunction with the BDA. With the aid of a registry, we are now able to describe risk profiles and associations in case of a complication. Moreover, a benchmark has been implemented in order to continuously improve complication rates.

Background and Objectives: This case report describes an unusual cause of misplacement of an indwelling catheter in the subarachnoid space after primary psoas compartment block in a patient undergoing total knee arthroplasty. Case Report: A 67-year-old woman presenting for total knee joint replacement received a combination of continuous psoas compartment block and sciatic nerve block. Neurostimulation and additional ultrasound guidance were used for identification of the lumbar plexus. After elicitation of a quadriceps motor response, a negative aspiration test, and an uneventful test dose, 20 mL ropivacaine 0.375% and 20 mL mepivacaine 1% were injected. Despite difficult ultrasound conditions because of intestinal air, local anesthetic spread was observed paravertebrally at the medial border of the psoas muscle as usual. A catheter was then advanced 7 cm through the insulated directional puncture needle. An additional sciatic nerve block was performed by using Labat9s approach. Ten minutes after injection unilateral sensory block was noted and surgery was started. After uneventful surgery, bilateral sensory block to the T4 level and complete motor block in both lower limbs was detected. A second aspiration test was negative, and an epidural block was suspected. For verification of the catheter tip location, a computed tomography scan with contrast dye was performed revealing catheter placement in the subarachnoid space. The catheter was removed and showed a kink about 7 cm from the tip. After regression of the neuraxial block, lumbar plexus block persisted for another 2 hours. Conclusion: An additional test dose via the catheter is recommended if the indwelling catheter is inserted after injection of the local anesthetics through the puncture needle. If epidural anesthesia occurs, an x-ray of the catheter is advisable because negative aspiration via catheter does not rule out subarachnoid catheter location.