Background: Electrical impedance tomography (EIT) with indicator dilution may be clinically useful to measure relative lung perfusion, but there is limited information on the performance of this technique. Methods: Thirteen pigs (50e66 kg) were anaesthetised and mechanically ventilated. Sequential changes in ventilation were made: (i) right-lung ventilation with left-lung collapse, (ii) two-lung ventilation with optimised PEEP, (iii) two-lung ventilation with zero PEEP after saline lung lavage, (iv) two-lung ventilation with maximum PEEP (20/25 cm H 2 O to achieve peak airway pressure 45 cm H 2 O), and (v) two-lung ventilation under unilateral pulmonary artery occlusion. Relative lung perfusion was assessed with EIT and central venous injection of saline 3%, 5%, and 10% (10 ml) during breath holds. Relative perfusion was determined by positron emission tomography (PET) using 68 Gallium-labelled microspheres. EIT and PET were compared in eight regions of equal ventro-dorsal height (right, left, ventral, mid-ventral, mid-dorsal, and dorsal), and directional changes in regional perfusion were determined. Results: Differences between methods were relatively small (95% of values differed by less than 8.7%, 8.9%, and 9.5% for saline 10%, 5%, and 3%, respectively). Compared with PET, EIT underestimated relative perfusion in dependent, and overestimated it in non-dependent, regions. EIT and PET detected the same direction of change in relative lung perfusion in 68.9e95.9% of measurements. Conclusions: The agreement between EIT and PET for measuring and tracking changes of relative lung perfusion was satisfactory for clinical purposes. Indicator-based EIT may prove useful for measuring pulmonary perfusion at bedside.

Historically, method-oriented middleware, such as Sun RPC, DCE, Java RMI, COM, and CORBA, has

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The ASDEX Upgrade (AUG) system for glow discharge (GD) has been revised comprehensively. This was necessary due to technical as well as operational requirements. The available space with in the low field side of the vacuum vessel is strongly limited because it's the preferred place for diagnostics. The new development based on the design of the W7-X anode now has a smaller footprint, is long term reliable and easier maintainable. Additionally each of the anodes is equipped with a separate starting device. The use of this device now allows the fast ignition of GD at operational pressure without the need of a short-term pressure increase. With the change from carbon to tungsten plasma-facing components (PFCs) an enhanced Helium (He) content at plasma discharges was observed for unboronized walls and the implantation of He during GD could be identified as source. For this reason the use of He GD has to be strongly reduced. It turned out that pulsed GDs of about 10 seconds length followed by a pumping down phase are sufficient to clean the wall. This mode of operation requires a reliable breakdown of the GD at operating pressure. This paper gives an overview of the technical setup and first measurement results.