Search results for "Suction."
showing 10 items of 70 documents
Recommended practice for out-of-hospital emergency anaesthesia in adults: Statement from the Out-of-Hospital Emergency Anaesthesia Working Group of t…
2016
Emergency anaesthesia is an important therapeutic measure in out-of-hospital emergency medicine. The associated risks are considerably higher than those of in-hospital anaesthesia. The primary objectives of emergency anaesthesia are hypnosis, analgesia, oxygenation and ventilation through airway management. The secondary objectives of emergency anaesthesia are amnesia, anxiolysis, the reduction of oxygen consumption and respiratory work, the protection of vital organs and the avoidance of secondary myocardial and cerebral damage. A critical evaluation of the indications for outof- hospital emergency anaesthesia must take into consideration patient, case and provider-related factors. Rapid s…
Gasless laparoscopy with conventional surgical instruments
1996
The main advantages of gasless laparoscopy arise from the use of conventional laparotomy instruments (clamps, scissors and needle pushers). The operative time, for example, for hysterectomy procedures decreases to about 60% of the time taken hysterectomy for using conventional gas techniques. During cauterization, smoke escapes immediately through the open trocars and may even be suctioned using a conventional suction tube. As far as the nursing team is concerned, the equipment is familiar as they use the same instruments and the same sutures as in laparotomy. High respiration pressure, caused by the elevated abdominal pressure, as well as hypercapnia, are avoided. Therefore this procedure …
Entfernung von subfovealem Perfluorcarbon durch ein therapeutisches Makulaforamen
2018
Die Herzpunktion bei der Ratte zur wiederholten Blutentnahme und Injektion
1971
Cardiopunkture in anesthesia is a rapid and accurate method for withdrawal of blood and injection without as many complications as suspected if carried out correctly. In the animal placed on its back a syringe with a gauge-24 needle is inserted in the left 4th or 5th intercostal space close to the sternum. When the needle is slowly pushed forward toward the spine continuous suction is exerted with the plunger. After blood has been drawn the needle is removed with a quick jerk. Thus when rats were punctured 8 to 18 times only 1 animal died of a hemopericard in 275 punctures. No other complication could be observed.
A Comparative Study of Soil Suction Measurement Using Two Different High-Range Psychrometers
2007
An extensive experimental study was performed to compare the measurement capabilities within different ranges of two total suction measurement equipment: SMI transistor psychrometers and a chilled-mirror dew-point psychrometer (WP4 Dewpoint PotentiaMeter). The equipment were used in a systematic way to determine the relative humidity of the environment surrounding different compacted clayey soils along drying paths and covering a wide total suction range (0.1 to 70 MPa). The equipment description and the calibration protocols followed are presented, as well as suggestions regarding the improvement of their performance. The water retention curves of two different compacted clayey soils are p…
Mechanical behaviour of compacted scaly clay during cyclic controlled-suction testing
2007
Scaly clays are stiff and highly fissured soils due to their complex geological history. Owing to these characteristics, they may be placed and compacted as excavated, to obtain a material with adequate engineering properties, suitable as core material in earth dams and in waste isolation fills. With reference to these engineering applications, an exhaustive experimental programme is developed to characterise the hydro-mechanical behaviour of this compacted material under a variety of controlled-suction paths. This paper presents selected test results, focusing on the interpretation of specific behavioural features of the volume change of this complex material; namely, the strain accumulati…
Hydraulic Characterization of a Pervious Concrete for Deep Draining Trenches
2018
Reduction in pore water pressure is an useful strategy to improve the stability of slopes. Deep draining trenches can be used for this purpose. For the realization of deep trenches, the usual conventional construction techniques are not adequate and the use of adjacent vertical panels, built by means of the methods well-established for diaphragm walls, is necessary. However, unbonded materials (i.e., gravels) cannot be used, because the excavation of a panel adjacent to one already built will cause instability. For this scope a bonded material such as pervious concrete can be used. It must have high permeability; filtering capacity, in order to prevent internal erosion of the soil in which …
Volumetric Behaviour of Lime Treated High Plasticity Clay Subjected to Suction Controlled Drying and Wetting Cycles
2017
The paper presents some experimental results collected on samples recovered from an experimental embankment obtained by compacting a lime-treated clay. Samples were collected soon after the in situ compaction and they were cured in controlled environmental conditions for at least 18 months. Mercury intrusion porosimetry tests (MIP) were carried out on freeze-dried specimens to characterize the microstructure of the material. In order to assess the durability of the improved material, laboratory tests focused on the effects of cyclic variations of the degree of saturation on the water retention properties and the volumetric behaviour of the stabilized clay. Collected results show that the li…
Stress path dependence of hydromechanical behaviour of compacted scaly clay in wetting and drying suction controlled oedometer tests at constant vert…
2008
The results are presented of an experimental programme devoted to investigating the volumetric strain and water ratio (volume of water to volume of solids) evolution of a compacted scaly clay stressed by wetting and drying cycles in suction-controlled oedometer tests. The stress paths applied included loading and unloading cycles at constant matric suction and suction controlled wetting-drying cycles at constant vertical net stress. The test results show that during wetting and drying cycles the samples experienced irreversible shrinkage or swelling strains depending on the stress path applied. Irreversible water ratio increases were always observed in these cycles. However, a quasi-reversi…
Volume change behaviour of a compacted scaly clay during cyclic suction changes
2010
The research presented in this paper focuses on the investigation and modelling of the volume change response of compacted tectonised clay samples subjected to several wetting and drying cycles in controlled-suction oedometers. Oedometer tests were carried out under different values of constant vertical net stress, and wetting and drying cycles were performed varying applied matric suction between 10 and 800 kPa. The investigation was complemented with a study of the material microstructure to support the interpretation of the overall mechanical response. At a microscopic level, the material is characterized by different types of particle assemblages, scales, and clay aggregates. One of th…