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Ultrasound-guided intermediate cervical plexus blockade with perivascular infiltration of the carotid artery bifurcation perivacular block (PVB) is a reliable technique for regional anesthesia in carotid endarterectomy (CEA). We investigated the effect of the carotid bifurcation level (CBL) on PVB efficacy and safety in patients undergoing CEA. This prospective observational cohort study included 447 consecutive CEA patients who received PVB over a 6-y period. Vascular and neurologic puncture-related complications were recorded. The CBL was localized at the low level (C4 and C5 vertebra, low-level [LL] group) in 381 (85.2%) patients and at the high level (C2 and C3 vertebra, high-level [HL] group) in 66 (14.8%) patients. Local anesthetic supplementation by surgeons was necessary in 64 (14.3%) patients in the LL group and 38 (59.4%) patients in the HL group (p < 0.001) and was associated with a higher rate of central neurologic complications in the HL group (p = 0.031). Therefore, the efficacy of the PVB may be influenced by the CBL.

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).

Purpose Postoperative pain is a major concern following scoliosis surgery. CEA (continuous epidural analgesia) is established in postoperative pain therapy as well as intravenous patient-controlled analgesia (IV-PCA). The purpose of this study was to compare the clinical outcomes of both methods. Methods We retrospectively studied 175 children between 8 and 18 years who were subject to posterior scoliosis correction and fusion. Two main cohorts were formed: CEA with local anesthetic and opioids, and IV-PCA with opioids. Both groups further comprised two sub-cohorts: those who were mentally and/or physically healthy (H; n = 93 vs. n = 30) and those who were impaired (I; n = 26 vs. n = 26). The outcome parameters were the demand for pain medication, parameters of mobilization, and the presence of adverse reactions. Results Healthy children who received CEA started mobilization 1 day earlier than children with IV-PCA (p = 0.002). First postsurgical defecation was seen earlier in all children who received CEA in both groups (H; Day 4 vs. Day 5, p = 0.011, I; Day 3 vs. Day 5, p = 0.044). Healthy children who received CEA were discharged from hospital 4 days earlier than their IV-PCA counterparts (p Conclusions CEA provides appropriate pain management after scoliosis surgery, regardless of the patient’s mental status. It allows earlier postoperative defecation for all patients , as well as shorter hospitalization and an earlier mobilization for healthy patients.

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.Rumpfblockaden zur Regionalanästhesie haben mit Einführung der Sonographie eine neue Bedeutung erfahren. Durch Umgehung von zu meidenden Begleitstrukturen hilft der Ultraschall, Komplikationen zu vermeiden. Zusätzlich sind komplexe Punktionen möglich, die allein durch Landmarken zu risikoreich wären. Neben der gezielten Blockade einzelner Nervenstrukturen haben sich auch interfasziale bzw. Kompartimentblockaden etabliert, bei denen die Darstellung einzelner Nerven oder Plexusstrukturen nicht von Bedeutung ist. Die vorliegende Übersichtsarbeit beschreibt publizierte und klinisch etablierte Punktionstechniken bezüglich ihrer Indikationen und Durchführung. Es wird erläutert, welchen Stellenwert sie in Bezug auf Wirkungsprofil und klinisch-wissenschaftliche Evidenz haben. Weiterhin erläutern die Autoren mögliche Komplikationen, Risiken und Lokalanästhetikadosierungen.

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.

Ultrasound guided distal sciatic nerve block (DSB) at bifurcation level shows fast onset and provides excellent success rates. However, its safe performance might be difficult for the unexperienced physician. Just slightly distal to the bifurcation, the tibial nerve (TN) and common fibular nerve (CFN) can be shown clearly separated from each other. Therefore, we investigated if a block done here would provide similar quality results compared to the DSB proximally to the division, with a potentially lower risk of nerve damage.In this randomized, prospective trial, 56 patients per group received either a DSB distal to the bifurcation "out-of-plane" (dist.) or proximally "in-plane" (prox.) with 30 ml of Mepivacaine 1% each. Success was tested by a blinded examiner after 15 and 30 min respectively (sensory and motor block of TN and CFN: 0 = none, 2 = complete, change of skin temperature). Videos of the blocks were inspected by an independent expert retrospectively with regard to the spread of the local anesthetic (LA) and accidental intraneural injection.Cumulative single nerve measurements and temperature changes revealed significant shorter onset and better efficacy (dist/prox: 15 min: 3.13 ± 1.86/1.82 ± 1.62; 30 min: 5.73 ± 1.92/3.21 ± 1.88; TThe subparaneural spread of the LA turned out to be crucial for better results in the distal group. The steep angle using the out-of-plane approach favors needle penetration through the paraneural sheath. The distance between the branches allows the safe application of the LA, so an effective block can be done with just one injection.DSB slightly distal to the bifurcation, in an out-of-plane technique between the TN and CFN, can be done fast, effectively and safe.

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.

To 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 für Anästhesiologie und Intensivmedizin, DGAI) and the Professional Association of German Anaesthetists (Berufsverband Deutscher Anästhesisten, BDA) initiated a network for safety in regional anaesthesia. From this the first results on infectious complications will be reported.In 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.After 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%, p0.0001). Multiple punctures of the skin also seem to be associated with a higher infection rate than single skin punctures (4.1% vs. 1.6%, p0.0001).Infectious complications of catheter-based regional anaesthesia are common. Strict hygienic standards must therefore be complied with. More data are necessary to calculate risk factors. The registry provided can also be used as a benchmark to reduce these rates further.

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.

Adequate postoperative pain management is of major importance for a short rehabilitation time after painful orthopaedic surgery. Multimodal pathways have been established to achieve a surgical patient free of pain and complications. Peripheral and central nerve blocks are a fundamental part of these interdisciplinary strategies and are already implemented in orthopaedic surgical care. This article summarises the value of special anaesthetic techniques, especially regional anaesthesia, in orthopaedic surgery and discusses their impact on several postoperative outcome goals.

The application of perfluorohexane (PFH) vapor led to an improvement of oxygenation and mechanical lung function in a model of oleic acid-induced ARDS in sheep. The aim of this study was to investigate the effects of PFH on gas exchange over an extended time period and to reduce the invasiveness of ventilation.ARDS was induced in sheep ( n=12) by injecting 0.1 ml/kg body weight oleic acid intravenously. Six sheep were treated for 30 min with 18 vol.% PFH (PFH-Tx) and followed up over a time period of 240 min while untreated sheep ( n=6) served as controls. Subsequently the F(I)O(2) was reduced to generate a p(a)O(2) between 100-140 mmHg. Gas exchange, respiratory and hemodynamic data were collected at regular intervals. Data were analysed using covariance analysis.PFH treatment led to an improvement in oxygenation ( p0.01) and in mechanical lung function ( p0.01). Furthermore, mean pulmonary artery pressure ( p0.01) and shunt ( p0.01) were lower in PFH-Tx. F(I)O(2) could be reduced in all PFH-treated animals ( p0.01).Treatment of oleic acid-induced lung injury with PFH vapor improved oxygenation and mechanical lung function over a extended time period allowing a reduction in the invasiveness of ventilation.

Inadvertent cranial extension of sympathetic and sensory block following posture change during spinal anaesthesia has been reported for isobaric as well as for hyperbaric local anaesthetics. We present the case of a patient who underwent surgical repair of a refracture of the tibia under spinal anaesthesia with 17.5 mg of isobaric 0.5% bupivacaine. The maximum level of sensory block (MLSB) reached T8 after 15 min. Following posture change into a 15 degrees anti-Trendelenburg position 35 min after lumbar puncture, the MLSB increased cranially for 10 segments and reached the C6 level after 10 min of anti-Trendelenburg position. The patient suffered from severe bradycardia and arterial hypotension which were treated with 6% hydroxyethyl starch, atropine and Akrinor. In addition, the patient developed respiratory insufficiency and was therefore intubated and the lungs were mechanically ventilated. The operation was performed uneventfully with the patient under general anaesthesia. At the end of surgery the trachea was extubated, and the patient was awake with stable hemodynamics, sufficient spontaneous ventilation and free of pain. MLSB reached the second lumbar dermatome. This case shows that after assumed fixation of the local anaesthetic an inadvertent extension of the MLSB following posture change is possible. Close surveillance is recommended for patients with central neuraxial blocks until the block is in complete remission. The mechanisms for inadvertent high extension of the MLSB following posture change are discussed.

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.