Fully Automatic Method for Reliable Spinal Cord Compartment Segmentation in Multiple Sclerosis.

BACKGROUND AND PURPOSE: Fully automatic quantification methods of spinal cord compartments are needed to study pathologic changes of the spinal cord GM and WM in MS in vivo. We propose a novel method for automatic spinal cord compartment segmentation (SCORE) in patients with MS. MATERIALS AND METHODS: The cervical spinal cords of 24 patients with MS and 24 sex- and age-matched healthy controls were scanned on a 3T MR imaging system, including an averaged magnetization inversion recovery acquisition sequence. Three experienced raters manually segmented the spinal cord GM and WM, anterior and posterior horns, gray commissure, and MS lesions. Subsequently, manual segmentations were used to train neural segmentation networks of spinal cord compartments with multidimensional gated recurrent units in a 3-fold cross-validation fashion. Total intracranial volumes were quantified using FreeSurfer. RESULTS: The intra- and intersession reproducibility of SCORE was high in all spinal cord compartments (eg, mean relative SD of GM and WM: ≤ 3.50% and ≤1.47%, respectively) and was better than manual segmentations (all P < .001). The accuracy of SCORE compared with manual segmentations was excellent, both in healthy controls and in patients with MS (Dice similarity coefficients of GM and WM: ≥ 0.84 and ≥0.92, respectively). Patients with MS had lower total WM areas (P < .05), and total anterior horn areas (P < .01 respectively), as measured with SCORE. CONCLUSIONS: We demonstrate a novel, reliable quantification method for spinal cord tissue segmentation in healthy controls and patients with MS and other neurologic disorders affecting the spinal cord. Patients with MS have reduced areas in specific spinal cord tissue compartments, which may be used as MS biomarkers.

Kv4 channel expression and kinetics in GABAergic and non-GABAergic rNST neurons.

The rostral nucleus of the solitary tract (rNST) serves as the first central relay in the gustatory system. In addition to synaptic interactions, central processing is also influenced by the ion channel composition of individual neurons. For example, voltage-gated K+ channels such as outward K+ current (IA) can modify the integrative properties of neurons. IA currents are prevalent in rNST projection cells but are also found to a lesser extent in GABAergic interneurons. However, characterization of the kinetic properties of IA, the molecular basis of these currents, as well as the consequences of IA on spiking properties of identified rNST cells is lacking. Here, we show that IA in rNST GABAergic (G+) and non-GABAergic (G-) neurons share a common molecular basis. In both cell types, there was a reduction in IA following treatment with the specific Kv4 channel blocker AmmTx3. However, the kinetics of activation and inactivation of IA in the two cell types were different with G- neurons having significantly more negative half-maximal activation and inactivation values. Likewise, under current clamp, G- cells had significantly longer delays to spike initiation in response to a depolarizing stimulus preceded by a hyperpolarizing prepulse. Computational modeling and dynamic clamp suggest that differences in the activation half-maximum may account for the differences in delay. We further observed evidence for a window current under both voltage clamp and current clamp protocols. We speculate that the location of Kv4.3 channels on dendrites, together with a window current for IA at rest, serves to regulate excitatory afferent inputs.NEW & NOTEWORTHY Here, we demonstrate that the transient outward K+ current IA occurs in both GABAergic and non-GABAergic neurons via Kv4.3 channels in the rostral (gustatory) solitary nucleus. Although found in both cell types, IA is more prevalent in non-GABAergic cells; a larger conductance at more negative potentials leads to a greater impact on spike initiation compared with GABAergic neurons. An IA window current further suggests that IA can regulate excitatory afferent input to the nucleus.

How memory effects, check dams, and channel geometry control erosion and deposition by debris flows.

Debris flows can grow greatly in size and hazardous potential by eroding bed and bank material, but effective hazard assessment and mitigation is currently hampered by limited understanding of erosion and deposition dynamics. We have collected high-resolution pre- and post-flow topography for 6 debris flows over a 3 km long unconsolidated reach of the Illgraben channel in the Swiss Alps with drone-based photogrammetry. We show that the spatio-temporal patterns of erosion and deposition in debris-flow torrents are highly variable and dynamic. Check dams strongly control the spatial patterns of erosion and deposition. We identify a memory effect where erosion is strong at locations of strong deposition during previous flows and vice versa. Large sediment inputs from subcatchments initially result in new channel erosion through the subcatchment deposits and simultaneous upstream deposition, likely as a result of backwater effects. It is generally believed that erosion increases with debris-flow magnitude, but we show that there is a limit to debris-flow bulking set by channel geometry. These findings provide key guidelines for flow volume forecasting, emphasizing the importance of memory effects and the need to resolve both erosion and deposition in predictive models.

Initiation and Flow Conditions of Contemporary Flows in Martian Gullies.

Understanding the initial and flow conditions of contemporary flows in Martian gullies, generally believed to be triggered and fluidized by CO2 sublimation, is crucial for deciphering climate conditions needed to trigger and sustain them. We employ the RAMMS (RApid Mass Movement Simulation) debris flow and avalanche model to back calculate initial and flow conditions of recent flows in three gullies in Hale crater. We infer minimum release depths of 1.0-1.5 m and initial release volumes of 100-200 m3. Entrainment leads to final flow volumes that are ∼2.5-5.5 times larger than initially released, and entrainment is found necessary to match the observed flow deposits. Simulated mean cross-channel flow velocities decrease from 3-4 m/s to ∼1 m/s from release area to flow terminus, while flow depths generally decrease from 0.5-1 to 0.1-0.2 m. The mean cross-channel erosion depth and deposition thicknesses are ∼0.1-0.3 m. Back-calculated dry-Coulomb friction ranges from 0.1 to 0.25 and viscous-turbulent friction between 100 and 200 m/s2, which are values similar to those of granular debris flows on Earth. These results suggest that recent flows in gullies are fluidized to a similar degree as are granular debris flows on Earth. Using a novel model for mass flow fluidization by CO2 sublimation we are able to show that under Martian atmospheric conditions very small volumetric fractions of CO2 of ≪1% within mass flows may indeed yield sufficiently large gas fluxes to cause fluidization and enhance flow mobility.

Automatic Spinal Cord Gray Matter Quantification: A Novel Approach.

BACKGROUND AND PURPOSE: Currently, accurate and reproducible spinal cord GM segmentation remains challenging and a noninvasive broadly accepted reference standard for spinal cord GM measurements is still a matter of ongoing discussion. Our aim was to assess the reproducibility and accuracy of cervical spinal cord GM and WM cross-sectional area measurements using averaged magnetization inversion recovery acquisitions images and a fully-automatic postprocessing segmentation algorithm. MATERIALS AND METHODS: The cervical spinal cord of 24 healthy subjects (14 women; mean age, 40 ± 11 years) was scanned in a test-retest fashion on a 3T MR imaging system. Twelve axial averaged magnetization inversion recovery acquisitions slices were acquired over a 48-mm cord segment. GM and WM were both manually segmented by 2 experienced readers and compared with an automatic variational segmentation algorithm with a shape prior modified for 3D data with a slice similarity prior. Precision and accuracy of the automatic method were evaluated using coefficients of variation and Dice similarity coefficients. RESULTS: The mean GM area was 17.20 ± 2.28 mm2 and the mean WM area was 72.71 ± 7.55 mm2 using the automatic method. Reproducibility was high for both methods, while being better for the automatic approach (all mean automatic coefficients of variation, ≤4.77%; all differences, P < .001). The accuracy of the automatic method compared with the manual reference standard was excellent (mean Dice similarity coefficients: 0.86 ± 0.04 for GM and 0.90 ± 0.03 for WM). The automatic approach demonstrated similar coefficients of variation between intra- and intersession reproducibility as well as among all acquired spinal cord slices. CONCLUSIONS: Our novel approach including the averaged magnetization inversion recovery acquisitions sequence and a fully-automated postprocessing segmentation algorithm demonstrated an accurate and reproducible spinal cord GM and WM segmentation. This pipeline is promising for both the exploration of longitudinal structural GM changes and application in clinical settings in disorders affecting the spinal cord.

Pulsating Magnetic Reconnection Driven by Three-Dimensional Flux-Rope Interactions.

The dynamics of magnetic reconnection is investigated in a laboratory experiment consisting of two magnetic flux ropes, with currents slightly above the threshold for the kink instability. The evolution features periodic bursts of magnetic reconnection. To diagnose this complex evolution, volumetric three-dimensional data were acquired for both the magnetic and electric fields, allowing key field-line mapping quantities to be directly evaluated for the first time with experimental data. The ropes interact by rotating about each other and periodically bouncing at the kink frequency. During each reconnection event, the formation of a quasiseparatrix layer (QSL) is observed in the magnetic field between the flux ropes. Furthermore, a clear correlation is demonstrated between the quasiseparatrix layer and enhanced values of the quasipotential computed by integrating the parallel electric field along magnetic field lines. These results provide clear evidence that field lines passing through the quasiseparatrix layer are undergoing reconnection and give a direct measure of the nonlinear reconnection rate. The measurements suggest that the parallel electric field within the QSL is supported predominantly by electron pressure; however, resistivity may play a role.

[Monitoring tidal volumes when using the Ventrain® emergency ventilator]. / Monitoring der Tidalvolumina bei Verwendung des Ventrain® Notfallbeatmungsgerätes.

BACKGROUND: The Ventrain® emergency ventilation device allows active inspiration and expiration through transtracheal catheters or the lumen of an airway exchange catheter. This single-use handheld device is manually operated and driven by an external pressurized oxygen source. The Ventrain® may be used to ventilate patients with a complete or pending upper airway obstruction reducing the risk of barotrauma due to the possibility of active expiration. However tidal volumes (V T) applied and withdrawn with the Ventrain® can only be controlled by visual inspection of chest movements; V T monitoring is not provided. Excessive inspiratory volumes or air trapping due to insufficient expiration may remain clinically undetected until pulmonary trauma and/or cardio-respiratory deterioration occur. Active expiration itself carries the risk of overwhelming lung deflation with the formation of atelectasis. Thus, an inspiratory and expiratory tidal volume monitor is urgently required. The aim of this study was to evaluate efficacy and precision of the Florian respiratory function monitor (RFM) to monitor in- and expiratory V T administered by the Ventrain® emergency ventilation device through a small cannula to the ASL 5000 test lung (ASL). METHODS: In an in-vitro setting the RFM was used with its neonatal flow sensor to monitor inspiratory and expiratory V T applied by the Ventrain® emergency ventilation device through a 2 mm internal diameter (ID) transtracheal catheter to the ASL. Driving flows of 6, 9, 12 and 15 l min(-1) were chosen to vary tidal volumes at a constant respiratory rate of 15 min(-1) and an I:E ratio of 1:1. Experiments were repeated five times with two flow sensors. An initial set-up calibration run was performed to calculate a bias correction factor for inspiratory and expiratory V T measured by the RFM. This bias correction factor was used to simulate a correction of the in the RFM programmed linearization table. In a second, identical setting the experiments were repeated five times with two flow sensors. V T measured by the adjusted RFM were compared with those obtained from the ASL 5000 in this second run and the percentage differences were calculated. Bland Altman analysis was used to investigate the agreement of inspiratory or expiratory VT measured by both methods (ASL and RFM). Calculation of the mean of differences between both methods is given as bias and the 95 % agreement interval as precision. RESULTS: Tidal volumes measured by the ASL ranged from 140 to 675 ml. The percentage correction factor was 16.27 % (2.60 %) during inspiration for V T ranged from 0 to 700 ml and 11.51 % (2.56 %) during expiration for V T of 0 to 225 ml, 7.41 % (2.94 %) for VT 226 to 325 ml and 5.35 % (3.57 %) for TV e > 325 ml. Inspiratory and expiratory tidal volumes measured by the adjusted RFM demonstrated a percentage deviation (mean [SD]) of 2.59 % (1.86 %) during inspiration and 1.66 % (1.14 %) during expiration when compared with the ASL 5000. Bias (precision) of the Bland Altman plot for the adjusted RFM is 2.05 ml (23.20) during inspiration and 4.62 ml (10.40) for expiration. CONCLUSION: The tested respiratory function monitor using hot-wire anemometer technology has the potential to monitor tidal volumes applied by the Ventrain®. With the software thus adapted, the RFM measures precise inspiratory and expiratory tidal volumes within common technical tolerance. This could help perform adequate patient ventilation with Ventrain® and reduce the potential risk of patient trauma.

The efficacy and safety of either infliximab or adalimumab in 362 patients with anti-TNF-α naïve Crohn's disease.

BACKGROUND: TNFα antagonists, including infliximab (IFX) and adalimumab (ADA), have revolutionised treatment for Crohn's disease. Studies comparing efficacy in patients with Crohn's disease naïve to TNFα antagonists are lacking. METHODS: Consecutive TNFα antagonist-naïve patients with luminal or perianal Crohn's disease from four tertiary centres in Austria were assessed prospectively for induction and maintenance efficacy, and safety, of either IFX or ADA. RESULTS: In a total of 362 patients, 251 (69.3%) started IFX and 111 (30.7%) started ADA. At baseline, the median Harvey-Bradshaw Index (HBI) score was 8 (range 5-29) and 8 (5-36), and the median C-reactive protein (CRP) was 1.07 (interquartile range (IQR) 1.36) mg/dL and 1.16 (IQR 1.23) mg/dL for IFX and ADA, respectively. At week 12, there was no difference between IFX and ADA among patients with luminal Crohn's disease in clinical remission (IFX 128/204; 62.7% vs. ADA 68/107; 63.6%, P = 0.47), clinical response (IFX 154/204; 75.5% vs. ADA 82/107; 76.6%, P = 0.82) and steroid-free remission (IFX 110/204; 53.9% vs. ADA 61/107; 57%, P = 0.60). At 12 months, there were similar numbers of patients treated with IFX and ADA who maintained clinical remission (IFX 77/154; 50.4% vs. ADA 47/82; 57.3%, P = 0.48) and steroid-free remission (IFX 68/154; 44.3% vs. ADA 44/82; 53.7%, P = 0.16). Baseline CRP >0.7 mg/dL (OR 0.24; 95% CI 0.07-0.77, P = 0.01) was the only predictor of clinical remission at 12 months in patients who did not have escalation of anti-TNFα therapy. CONCLUSION: IFX and ADA appear comparable in clinical outcomes for patients with Crohn's disease who are naïve to TNFα antagonists.

Impact of oxygen sources on performance of the Ventrain(®) ventilation device in an in vitro set-up.

BACKGROUND: The Ventrain(®) (Dolphys Medical, Eindhoven, The Netherlands) is a disposable handheld ventilation device allowing active inspiration and expiration through a transtracheal catheter. This study investigated Ventrain(®) 's performance when used with different clinical oxygen sources in an in vitro set-up. METHODS: Three anesthesia oxygen sources (wall-mounted flowmeter, respirator oxygen outlet port, and anesthesia ventilator circuit) were used at gas flow rates of 6, 9, 12, and 15 l/min. First, the sources' driving pressures (DP), the insufflation pressure (IP), and the flow at the catheter tip were measured using a gas flow analyzer. Tidal volumes (VT) delivered by the Ventrain(®) were assessed by the ASL5000 test lung (respiratory rate: 15 min(-1), I:E = 1:1, compliance: 100 ml/cmH2O, resistance: 3.06 cmH2O/l/s). RESULTS: VT ranged from 82 to 483 ml for inspiration and 82 to 419 ml for expiration. Measured IP, flow, and VT were less dependent on the set gas flow rate but more on the source's DP. With rising DP the IP, the flow at the catheter tip and consequently VT increased. At an approximate target I:E ratio of 1:1, the ratio of inspiratory to expiratory VT increased with higher DP and gas flow rates. CONCLUSION: The oxygen sources resulted in clinically different IP, flows, and VT delivered by the Ventrain(®) at given gas flow rates. This needs to be considered in a clinical emergency situation. Integrating an adjustable pressure valve into Ventrain(®) to allow regulation of the lowest necessary IP would make its use safer.

[Comparison of five video laryngoscopes and conventional direct laryngoscopy : Investigations on simple and simulated difficult airways on the intubation trainer]. / Vergleich von fünf Videolaryngoskopen und direkter konventioneller Laryngoskopie : Untersuchung des einfachen und simulierten schwierigen Atemweg am Intubationstrainer.

INTRODUCTION: Securing the airway with a tracheal tube is essential in emergency situations, in the intensive care setting as well as during anesthesia for surgery and other interventions. Current methods of airway assessment are poor screening tests for predicting difficult direct laryngoscopy due to a generally low positive predictive value; therefore, successful endotracheal intubation requires a high level of expertise, regular training and practice and sometimes additional tools. Currently, several video laryngoscopes (VL) with different designs are commercially available and have been investigated in a wide variety of settings. To our knowledge there is no prospective study evaluating and comparing performance among these three groups of VL; therefore, the aim of this study was to compare performance of five VL and conventional direct laryngoscopy in an intubation manikin model, both in a normal and simulated difficult intubation setting. METHODS: In this study 10 residents, 12 senior staff physicians and 5 anesthesia nurses, all experienced in conventional direct laryngoscopy and inexperienced with VL underwent theoretical and hands-on training with all VL lasting 60 min. Afterwards participants performed intubation with all 5 VL and conventional direct laryngoscopy in a randomized sequence using an intubation manikin with normal intubation settings. Thereafter participants performed intubation in a simulated difficult intubation setting using the same intubation manikin with a neck collar to immobilize the cervical spine. In this study, the C-MAC(®) with Macintosh blade size 3, GlideScope(®) size 3, McGrath(®) series 5, King Vision(®) and Airtraq(®) size 2 were used. Time to intubation served as primary outcome and time to glottis visualization, number of intubation attempts, success rate and subjective evaluation of difficulty served as secondary outcomes. RESULTS: In the normal intubation setting, time to intubation ranged from 16.0 s (conventional direct laryngoscopy) to 34.3 s (McGrath). GlideScope and conventional direct laryngoscopy were successful in 100 % followed by C-MAC (96.7 %), Airtraq (88.9 %), King Vision (77.8 %) and McGrath VL (44.4 %). In the simulated difficult intubation setting, time to intubation ranged between 20.3 s (Airtraq) and 26.7 s (McGrath). Success rate with C-MAC was 100 %, followed by GlideScope (96.7 %), Airtraq (85.2 %), conventional direct laryngoscopy (85.2 %), King Vision (81.5 %) and McGrath VL (70.4 %). CONCLUSION: In the manikin with normal intubation setting, conventional direct laryngoscopy using a Macintosh blade was convincing and superior to any VL used in this study. During simulated difficult intubation, a blade with video transmission, such as C-MAC and the GlideScope were superior compared to conventional direct laryngoscopy and any other VL tested.

Earth-like aqueous debris-flow activity on Mars at high orbital obliquity in the last million years.

Liquid water is currently extremely rare on Mars, but was more abundant during periods of high obliquity in the last few millions of years. This is testified by the widespread occurrence of mid-latitude gullies: small catchment-fan systems. However, there are no direct estimates of the amount and frequency of liquid water generation during these periods. Here we determine debris-flow size, frequency and associated water volumes in Istok crater, and show that debris flows occurred at Earth-like frequencies during high-obliquity periods in the last million years on Mars. Results further imply that local accumulations of snow/ice within gullies were much more voluminous than currently predicted; melting must have yielded centimetres of liquid water in catchments; and recent aqueous activity in some mid-latitude craters was much more frequent than previously anticipated.

Higher fibrinogen concentrations for reduction of transfusion requirements during major paediatric surgery: A prospective randomised controlled trial.

BACKGROUND: Hypofibrinogenaemia is one of the main reasons for development of perioperative coagulopathy during major paediatric surgery. The aim of this study was to assess whether prophylactic maintenance of higher fibrinogen concentrations through administration of fibrinogen concentrate would decrease the volume of transfused red blood cell (RBCs). METHODS: In this prospective, randomised, clinical trial, patients aged 6 months to 17 yr undergoing craniosynostosis and scoliosis surgery received fibrinogen concentrate (30 mg kg(-1)) at two predefined intraoperative fibrinogen concentrations [ROTEM(®) FIBTEM maximum clot firmness (MCF) of <8 mm (conventional) or <13 mm (early substitution)]. Total volume of transfused RBCs was recorded over 24 h after start of surgery. RESULTS: Thirty children who underwent craniosynostosis surgery and 19 children who underwent scoliosis surgery were treated per protocol. During craniosynostosis surgery, children in the early substitution group received significantly less RBCs (median, 28 ml kg(-1); IQR, 21 to 50 ml kg(-1)) compared with the conventional fibrinogen trigger of <8 mm (median, 56 ml kg(-1); IQR, 28 to 62 ml kg(-1)) (P=0.03). Calculated blood loss as per cent of estimated total blood volume decreased from a median of 160% (IQR, 110-190%) to a median of 90% (IQR, 78-110%) (P=0.017). No significant changes were observed in the scoliosis surgery population. No bleeding events requiring surgical intervention, postoperative transfusions of RBCs, or treatment-related adverse events were observed. CONCLUSIONS: Intraoperative administration of fibrinogen concentrate using a FIBTEM MCF trigger level of <13 mm can be successfully used to significantly decrease bleeding, and transfusion requirements in the setting of craniosynostosis surgery, but not scoliosis. CLINICAL TRIAL REGISTRY NUMBER: ClinicalTrials.gov NCT01487837.

Muscle-derived vascular endothelial growth factor regulates microvascular remodelling in response to increased shear stress in mice.

AIM: The source of vascular endothelial growth factor-A (VEGF-A) may influence vascular function. Exercise-induced vascular growth has been attributed to elevated metabolic demand and to increased blood flow, involving the production of VEGF-A by skeletal muscle and by endothelial cells respectively. We hypothesized that muscle-derived VEGF-A is not required for vascular adaptations to blood flow in skeletal muscle, as this remodelling stimulus originates within the capillary. METHODS: Myocyte-specific VEGF-A (mVEGF(-/-) ) deleted mice were treated for 7-21 days with the vasodilator prazosin to produce a sustained increase in skeletal muscle blood flow. RESULTS: Capillary number increased in the extensor digitorum longus (EDL) muscle in response to prazosin in wild type but not mVEGF(-/-) mice. Prazosin increased the number of smooth muscle actin-positive blood vessels in the EDL of wild-type but not mVEGF(-/-) mice. The average size of smooth muscle actin-positive blood vessels also was smaller in knockout mice after prazosin treatment. In response to prazosin treatment, VEGF-A mRNA was elevated within the EDL of wild-type but not mVEGF(-/-) mice. Ex vivo incubation of wild-type EDL with a nitric oxide donor increased VEGF-A mRNA. Likewise, we demonstrated that nitric oxide donor treatment of cultured myoblasts stimulated an increase in VEGF-A mRNA and protein. CONCLUSION: These results suggest a link through which flow-mediated endothelial-derived signals may promote myocyte production of VEGF-A. In turn, myocyte-derived VEGF-A is required for appropriate flow-mediated microvascular remodelling. This highlights the importance of the local environment and paracrine interactions in the regulation of tissue perfusion.

Usefulness of standard plasma coagulation tests in the management of perioperative coagulopathic bleeding: is there any evidence?

Standard laboratory coagulation tests (SLTs) such as prothrombin time/international normalized ratio or partial thromboplastin time are frequently used to assess coagulopathy and to guide haemostatic interventions. However, this has been challenged by numerous reports, including the current European guidelines for perioperative bleeding management, which question the utility and reliability of SLTs in this setting. Furthermore, the arbitrary definition of coagulopathy (i.e. SLTs are prolonged by more than 1.5-fold) has been questioned. The present study aims to review the evidence for the usefulness of SLTs to assess coagulopathy and to guide bleeding management in the perioperative and massive bleeding setting. Medline was searched for investigations using results of SLTs as a means to determine coagulopathy or to guide bleeding management, and the outcomes (i.e. blood loss, transfusion requirements, mortality) were reported. A total of 11 guidelines for management of massive bleeding or perioperative bleeding and 64 studies investigating the usefulness of SLTs in this setting were identified and were included for final data synthesis. Referenced evidence for the usefulness of SLTs was found in only three prospective trials, investigating a total of 108 patients (whereby microvascular bleeding was a rare finding). Furthermore, no data from randomized controlled trials support the use of SLTs. In contrast, numerous investigations have challenged the reliability of SLTs to assess coagulopathy or guide bleeding management. There is actually no sound evidence from well-designed studies that confirm the usefulness of SLTs for diagnosis of coagulopathy or to guide haemostatic therapy.

[Intubation with a tube exchanger on an intubation trainer. Influence of tube tip position on successful intubation]. / Intubation über den Tubuswechsler an einem Intubationstrainer. Einfluss der Tubusspitzenposition auf den Intubationserfolg.

BACKGROUND: Securing the airway using a tube exchanger catheter is an important and useful technique in anesthesia. Its success is mainly hampered by tube tip impingement of laryngeal structures. Advancing the tracheal tube along its normal curvature via a tube exchanger catheter has a high risk of tube tip impingement mainly of right laryngeal structures. The authors achieved successful clinical experience by rotating the tracheal tube 90° anticlockwise (ventral tube tip position) before railroading the tube via a tube exchanger catheter or a fiber optic bronchoscope through the larynx. AIM: The aim of the study was to investigate the influence of the tracheal tube tip position while intubating an airway trainer over a tube exchange catheter. MATERIAL AND METHODS: Volunteer anesthetists with varying years of professional experience were asked to intubate an intubation mannequin (Laerdal Airway Management Trainer) using the orotracheal route with an established tube exchange catheter (Cook Airway Exchange Catheter, 11F). Two different brands of tracheal tubes (Rüsch and Covidien, ID 7.0 mm) were used in a randomized order, each with the tracheal tube tip at first positioned right (90°), then ventrally (0°), left (270°) and finally dorsally (180°), resulting in eight intubation attempts for each participant. To ensure the correct tube tip position the tube was withdrawn before every intubation attempt until the tube tip position was visualized. The oropharnyx, larynx, trachea and tube were sufficiently lubricated with silicon spray (Rüsch Silikospray). The tube and airway exchange catheter size selection were made according to the clinical trial of Loudermilk et al. Successful endotracheal intubation without resistance was recorded for each tube tip position and tracheal tube brand. RESULTS: In total 20 anesthetists (13 consultants and 7 residents) with a median of 9.5 years (range 3-37 years) of professional experience participated in the study. Overall 160 intubation attempts were performed, 2 participants showed no successful intubation attempts at all and 38 out of 160 intubation attempts (23.8 %) were successful. Intubation success with the tracheal tube tip placed ventrally (0°) was 60 % followed by the left (270°) and right (90°) tracheal tube tip positions with 27.5 % and 7.5 % intubation success, respectively. With the tube tip placed dorsally (180°) none of the 40 intubation attempts were successful. Intubation attempts with the Rüsch tube were more successful (28.8 %) than those with the Covidien tube (18.8 %). Placing the tracheal tube tip ventrally, the Rüsch tube was twice as successful as the Covidien tube with 16 (80 %) versus 8 attempts (40 %, p = 0.011). There was no correlation between professional experience and intubation success (p = 0.362). CONCLUSION: Tube insertion via an airway exchange catheter or a fiberoptic bronchoscope is a basic technique in anesthesia. Knowledge about the difficulties and their prevention are essential for every anesthetist. The gap between the airway exchange catheter, the fiber bronchoscope and the tube diameters is one of the major reasons for tube tip impingement. This investigation showed that intubation success via a tube exchange catheter, as investigated in an intubation mannequin, is considerably influenced by the tracheal tube tip position. A 90° anticlockwise rotation, placing the tracheal tube tip ventrally, considerably increased intubation success. This is of particular importance if an anesthesia department has no appropriately sized tube exchange catheters or fiber bronchoscope for every age group of patients.

[Nutrition and IBD-Consensus of the Austrian Working Group of IBD (Inflammatory Bowel Diseases) of the ÖGGH]. / Ernährung und chronisch entzündliche Darmerkrankungen - ein Konsensus der Arbeitsgruppe chronisch entzündliche Darmerkrankungen der Österreichischen Gesellschaft für Gastroenterologie und Hepatologie (Austrian Guidelines for nutrition in IBD).

This is a consensus of the Austrian working group of IBD (inflammatory bowel diseases) of the ÖGGH on nutrition in IBD. Malnutrition should be assessed in case of IBD (in 20 - 70 % of Crohn's patients) and weight loss(> 5 % within 3 months) or nutritional deficiencies or after extensive bowel resection and afterwards also treated. Malnutrition should be treated with medical therapy of IBD and also adequate - as far as possible - with oral nutritional therapy particularly because of reduced life quality, risk of opportunistic infections, osteopenia/osteoporosis, longer hospitalisations and higher mortality. Iron homeostasis, serum levels of Vitamin B12- and folic acid, 25-hydroxyvitamin D and zinc should be checked. Therapy with enteral liquid diets is only indicated as therapy of first choice in children and adolescents, but only in rare situations in adults with IBD. There is - up to now - no proven oral diet for maintenance of remission in IBD. Probiotics as E. coli Nissle could be used as alternative to mesalazine for maintenance of remission in patients with ulcerative colitis. A specific dietary counselling is mandatory in patients with ileostoma or short bowel syndrome. Malnutrition of short bowel patients is particularly dependent on the function and length of the remaining bowel, therefore the most effective medical therapy should be administered.