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Geert-Jan van Geffen,1 Hielke Markerink,1 Marc van Barneveld,2 Frank Verhoeven,3 Gert Jan Scheffer,1 Jörgen Bruhn1 1Department of Anesthesiology, Pain and Palliative Care, Radboud University Medical Centre (RUMC), Nijmegen, The Netherlands; 2Medspray Anesthesia BV, Enschede, The Netherlands; 3Medspray T&M, Enschede, The NetherlandsCorrespondence: Geert-Jan van GeffenDepartment of Anesthesiology, Pain and Palliative Care, Radboud University Medical Center, Internal Mail 717, P.O. Box 9101, Nijmegen, HB 6500, The NetherlandsTel +31 24 36 15 24 4Email Geert-Jan.vanGeffen@radboudumc.nlBackground: Obtaining complete topical anaesthesia of the airway remains a clinical challenge. Particle size is one of the most important variables for the dose deposited and the distribution of aerosols in the airways. The mass median aerodynamic diameter of the particles should be in the range of 5– 20 μm. We developed the “Trachospray” as a soft mist spray device for local anaesthetics. This in-vitro comparative test was designed to compare the performance of the new Trachospray device with two existing medical devices. The performance was determined by comparing the spray deposition patterns in the mouth, throat, trachea and lungs.Methods: The human airway was simulated with an artificial idealized mouth and throat model, connected to a Next Generation Impactor. Four measurements were taken for each device (Trachospray, jet nebulizer and a spray pump) with 5.85% NaCl. A fifth measurement was carried out with 0.5% fluorescein solution for a visual inspection of the deposition patterns. The mass median aerodynamic diameter and geometric standard deviation of the droplets were measured.Results: The Trachospray produced an even coverage in the mouth, hypopharynx and vocal cords, with only a small lung fraction. The jet nebulizer produced a much thinner layer coverage of the tongue and surface around the vocal chords with a high lung deposition. The spray pump produced big droplets which deposited mainly at the hypopharynx.Conclusion: The Trachospray device deposits local anaesthetics in the targeted areas for topical anaesthesia of the airway and has promising characteristics for providing effective airway anaesthesia.Keywords: airway model, geometric standard deviation, mass median aerodynamic diameter, medical device, topical airway anaesthesia

Item does not contain fulltext BACKGROUND: Failed spinal anesthesia for cesarean sections may require conversion to general anesthesia. The aim of this study was to determine whether the administered spinal bupivacaine dose for performing a cesarean section under spinal anesthesia was related to the conversion rate to general anesthesia. METHODS: Retrospective analysis was performed on 1252 electronic data and file of patients who underwent a cesarean section under spinal anesthesia between 2004 and 2011. RESULTS: In 15 patients, spinal anesthesia was converted into general anesthesia due to block failure. Patients in whom a bupivacaine dose of 8 mg or smaller was administered had significantly higher conversion rate (3/61 (4.9%) patients and 12/1191 (1.0%) patients, respectively; p < 0.05.). The relative risk of conversion with a 8 mg dose or lower is 4.88 (95% CI 1.41 - 16.85). CONCLUSION: This retrospective study shows that a low dose administration a bupivacaine 0.5% for spinal anesthesia in cesarean section patients elicits significantly more frequent conversion to general anesthesia.

Enterprise Applications (EA) are complex software systems for supporting the business of companies. Evolution of an EA should not affect its availability, e.g., because of a temporal shutdown, business operations may be affected. One possibility to address this problem is the seamless reconfiguration of the affected EA, i.e., applying the relevant changes while the system is running. Our approach to seamless reconfiguration focuses on component-oriented EAs. It is based on the Autonomic Computing infrastructure mKernel that enables the management of EAs that are realized using Enterprise Java Beans (EJB) 3.0 technology. In contrast to other approaches that provide no or only limited reconfiguration facilities, our approach consists of a comprehensive set of steps, that perform fine-grained reconfiguration tasks. These steps can be combined into generic and autonomous reconfiguration procedures for EJB-based EAs. The procedures are not limited to a certain reconfiguration strategy. Instead, our approach provides several reusable strategies and is extensible w.r.t. the opportunity to integrate new ones.

Proceedings Of The 6Th International Bci Meeting: Bci Past, Present, And Future

Contains fulltext : 88084.pdf (Publisher’s version ) (Closed access) BACKGROUND AND OBJECTIVES: Thoracic paravertebral block (TPVB) can be used for unilateral surgical procedures. Modifications of the classic approach have been proposed to minimize the risk of pleural puncture. In this study, we evaluated the feasibility and success rate of a transverse in-plane ultrasound (US)-guided TPVB with radiologic confirmation of catheter position. METHODS: A total of 36 patients scheduled for unilateral surgery with a TPVB catheter were included in this prospective study. Ultrasonographically, the transverse process of the thoracic vertebra and rib were identified at the appropriate thoracic level. The transducer was moved cranially until an intercostal US view was obtained, indicated by visualization of the parietal pleura. An in-plane needle insertion approach from lateral to medial was used, and a total of 20 mL ropivacaine 0.75% was injected through the needle and a subsequently threaded catheter, while the spread of local anesthetic was observed. Sensory spread of the block was evaluated by loss of cold sensation in the dermatomes. Catheter position was radiologically evaluated with radiopaque dye. RESULTS: Block success rate was 100%. In all patients, correct radiologic thoracic paravertebral catheter position was confirmed; 1 patient also showed additional epidural spread. The median number of total dermatomal segments with loss of cold sensation was 6. No pneumothorax or contralateral loss of cold sensation occurred. CONCLUSION: An in-plane transverse US-guided TPVB using the described technique is feasible and has a high success rate. In all patients, correct catheter position in the thoracic paravertebral space was radiologically confirmed.

Item does not contain fulltext This study was designed to investigate the impact of the Entropy Module and Bispectral Index (BIS) monitoring on drug consumption and recovery times compared with standard anaesthetic practice in patients undergoing orthopaedic surgery using a combination of regional and general anaesthesia as performed by an experienced anaesthesiologist. We hypothesised that electroencephalogram monitoring would lead to a lower drug consumption as well as shorter recovery times. With institutional review board approval and written informed consent, 90 adult patients undergoing surgery to the upper or lower extremity received regional anaesthesia for post- and intraoperative pain control and were randomised to receive general anaesthesia by propofol/remifentanil infusion controlled either solely by clinical parameters or by targeting Entropy or BIS values of 50. Recovery times and drug consumption were recorded. Data from 79 patients were analysed. Compared with standard practice, patients with Entropy or BIS monitoring showed a similar propofol consumption (standard practice 101 +/- 22 microg/kg/minute, Entropy 106 +/- 24 microg/kg/minute, BIS 104 +/- 20 microg/kg/minute) and showed similar Aldrete scores (10/10) one minute after extubation: 9.1 +/- 0.3, 9.2 +/- 0.6 and 9.3 +/- 0.5, respectively. Time points of extubation were 7.3 +/- 2.9 minutes, 9.2 +/- 3.9 minutes and 6.8 +/- 2.9 minutes, respectively, demonstrating a significant difference between Entropy and BIS (P = 0.023). Compared with standard practice, targeting an Entropy or BIS value of 50 did not result in a reduction of propofol consumption during general anaesthesia combined with regional anaesthesia as performed by an experienced anaesthesiologist in orthopaedic patients. 01 januari 2010

Contains fulltext : 69446.pdf (Publisher’s version ) (Closed access) BACKGROUND: The sciatic nerve block by the posterior approaches represents one of the more difficult ultrasound-guided nerve blocks. Our clinical experiences with these blocks indicated a point slightly distal to the subgluteal fold as an advantageous position to allow good ultrasonic visibility. In this study, we systematically scanned the sciatic nerve from the subgluteal fold to the popliteal crease, to determine an optimal point for ultrasonographic visualization. METHODS: After institutional approval and written informed consent, we recruited 15 volunteers to visualize the sciatic nerve from the subgluteal fold to the popliteal crease using a linear ultrasound probe in the range of 7-13 MHz. The ultrasonographic visibility of the sciatic nerve, nerve diameter (width and thickness), and skin-to-nerve distance at 20 equidistant points between the subgluteal fold and the popliteal crease were recorded. RESULTS: The sciatic nerve could be successfully visualized in cross-section as a hyperechoic structure on ultrasound in all volunteers. In the course from subgluteal to the popliteal area, the shape of the sciatic nerve changed from flat to round, while the skin-nerve distance varied with the smallest skin-nerve distances at the popliteal crease and at 5.4 cm (on average) distal to the subgluteal fold. The best ultrasonographic visibility scores were found between 7.2 and 10.8 cm (on average) distal to the gluteal fold. CONCLUSION: Between 5.4 and 10.8 cm from the subgluteal fold seems to be the best area to scan the sciatic nerve in terms of superficial nerve position and good ultrasonic visibility.

Contains fulltext : 69239.pdf (Publisher’s version ) (Closed access) In this in vitro study, a needle guidance device and a 'free hand' technique for ultrasound guided needle insertion were compared in a simulated ultrasound-guided interventional task using a porcine phantom. Residents inexperienced in using ultrasonography were asked to insert a needle, using an in-plane techniques, and to make contact with metal rods at a depth of 2 and 4 cm in the phantom. The transducer made angles of 90 degrees, 60 degrees and 45 degrees with the surface of the phantom. The times to perform the procedures were significantly shorter and the needle visualisation was significantly better when using the needle guidance device. The residents ranked their satisfaction with the needle-guidance device significantly better than the 'free-hand' technique. This device may be beneficial when performing ultrasound guided peripheral nerve blocks, especially by inexperienced operators.

Item does not contain fulltext Given the fast development and increasing clinical relevance of ultrasound guidance for thoracic paravertebral blockade, this review article strives (1) to provide comprehensive information on thoracic paravertebral space anatomy, tailored to the needs of a regional anesthesia practitioner, (2) to interpret ultrasound images of the thoracic paravertebral space using cross-sectional anatomical images that are matched in location and plane, and (3) to briefly describe and discuss different ultrasound-guided approaches to thoracic paravertebral blockade. To illustrate the pertinent anatomy, high-resolution photographs of anatomical cross-sections are used. By using voxel anatomy, it is possible to visualize the needle pathway of different approaches in the same human specimen. This offers a unique presentation of this complex anatomical region and is inherently more realistic than anatomical drawings.

Item does not contain fulltext Motor-impaired individuals such as tetraplegics could benefit from Brain-Computer Interfaces with an intuitive control mechanism, for instance for the control of a neuroprosthesis. Whereas BCI studies in healthy users commonly focus on motor imagery, for the eventual target users, namely patients, attempted movements could potentially be a more promising alternative. In the current study, EEG frequency information was used for classification of both imagined and attempted movements in tetraplegics. Although overall classification rates were considerably lower for tetraplegics than for the control group, both imagined and attempted movement were detectable. Classification rates were significantly higher for the attempted movement condition, with a mean rate of 77%. These results suggest that attempted movement is an appropriate task for BCI control in long-term paralysis patients. 3 p.

Item does not contain fulltext [Durham (UK)] Theoretical Roman Archaeology Conference 2004, 24 maart 2004 Durham (UK) : [s.n.]

Contains fulltext : 79741.pdf (Publisher’s version ) (Closed access) Since its commercial introduction in 1996, target-controlled infusion (TCI) has become an established technique for administration of intravenous anaesthetics. Modern TCI systems, however, are characterized by an increasing number of additional options and features, such as the choice between different pharmacokinetic models and modes of application, which may confuse the less experienced user. This review describes the differences between pharmacokinetic models, modes of application and the effect of covariates as well as the consequences for dosing. The aim is to explicate for the user of modern TCI systems the underlying scientific concepts and the relevance for clinical practice.

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Contains fulltext : 202624.pdf (Publisher’s version ) (Open Access) Radboud University, 01 mei 2019 Promotores : Scheffer, G.J., Velde, M. van de Co-promotores : Geffen, G.J. van, Bruhn, J.

Contains fulltext : 148937.pdf (Publisher’s version ) (Open Access) Radboud Universiteit Nijmegen, 22 december 2015 Promotores : Scheffer, G.J., Bruhn, J. Co-promotor : Farquhar, J.D.R.

Contains fulltext : 105837.pdf (Publisher’s version ) (Open Access) Radboud Universiteit Nijmegen, 18 maart 2013 Promotores : Scheffer, G.J., Bruhn, J. Co-promotor : Geffen, G.J. van

Contains fulltext : 98292.pdf (Publisher’s version ) (Open Access) Radboud Universiteit Nijmegen, 03 november 2011 Promotores : Scheffer, G.J., Bruhn, J. Co-promotores : Geffen, G.J. van, Gielen, M.J.M.