Abstract: The invention relates to a procedure for the perfusion of body cavities with a fluid led from a dispenser reservoir 3 via a perfusion line 10 and a medical instrument 6. Pump 4 is connected with the perfusion line 10, a pressure sensor 5 is connected between pump 4 and medical instrument 6 to perfusion line 10, and an adjustment and measurement electronic system 12 is connected to pressure sensor 5 and pump 4.To build up, maintain, and measure as precisely as possible a preselected and precisely determined pressure in the body cavity, according to the invention the adjustment and measurement electronic system 12 determines the actual pressure in body cavity 1 by evaluating the pressure P.sub.IST measured by pressure sensor 5, the volume flow V supplied by pump 4, and the conductance G of the perfusion line 9 between pressure sensor 5 and instrument 6 and conductance G of instrument 6, and the pressure P.sub.SOLL in body cavity 1 is maintained constant at preset level P.sub.

Abstract: The invention relates to a method and device for insufflating gas, in particular CO.sup.2 into the human or animal body, especially for laparoscope, with an insufflation instrument, for example, a Veress inflow needle, with the following structures arranged successively along a gas line a: pressure reducer 1a throughflow meter and pressure meter and with a control circuit connected with the throughflow meter and a pressure meter via respective control lines. The device is without noise-generating magnetic valves, and the intra-abdominal pressure can be measured continuously without elaborate switch overs. The pressure reducer is electrically controllable and connected with the evaluating and control circuit via a control line and is controllable via control line as a function of a clock generator and a nominal pressure generator.

Abstract: The invention is an apparatus for purifying polluted liquids, especially water. The apparatus comprises a vessel with a relatively large length to width ratio including a reaction zone for contacting the liquid with a gas, separated from the rest of the vessel by a downflow-upflow wall, having a liquid inlet means for introducing a liquid into the reaction zone, the flotation zone connected with the reaction zone occupying the rest of the vessel and a skimmer disposed at the end of the flotation zone for skimming off the floating materials to a channel arranged transverse to the longitudinal axis of the vessel and means for removing the purifying liquid from the apparatus.