Abstract:
Drainage belongs to medical equipment, particularly to medical tools and is specified for drainage of cavities. Drainage comprises a first tube, an additional tube, which is fixed upon it, a unit of the clot&#39;s splitter and the splitter&#39;s fixing element. The additional tube has a smaller diameter with an opening, inside which the conductor is mounted, a unit of clots splitter is installed on the working end of the drainage, it comprises a cylinder, a tube with an opening, placed on it, which is the continuation of the additional tube of the drainage and a spring with a cutter inside the cylinder. A cutter is located diametrically inside the working head, while in the end of the wall of the first tube and the splitter&#39;s unit comprises a channel, inside which splitter&#39;s fixing element was led, its working end is inside the unit&#39;s cylinder and fixes the splitter. This design ensures the permeability of the wound channel after the drainage is removed and it is possible to reinstall drainage into the cavity strictly along the existing wound channel.

Description:
This application is the United States national phase application of Ukrainian Patent Application No. 2008 05098 filed Apr. 21, 2008 incorporated therein by reference. 
     FIELD OF THE INVENTION 
     The presented technical solution deals with medical equipment, particularly with tools for surgery and is specified for draining of cavities after various types of surgical operations. 
     BACKGROUND OF THE INVENTION 
     In surgery a necessity of long draining of cavities often arises. Drainage of various designs is used for this purpose, the appliances are inserted into the drained cavity, ensuring active or passive aspiration. The main and so far unsolved problem of prolong drainage of cavities remains maintaining of permeability of drainage and ensuring the natural process of gradual constriction of wound channel as the cavity heals. Unfortunately despite constant perfection of the design of drainage systems, the drainage opening after some time is obturated with fibrin&#39;s clot. In this case drainage is removed and a new drainage system is installed into the drained cavity. Unfortunately it is practically impossible to insert a new drainage into the drained cavity using the old wound passage. This is explained by two main reasons. Firstly, the wound passage is of winding shape on the spot of the removed drainage system and it is practically impossible to lead a new drainage through all its turns. Secondly, fibrin&#39;s clots that are found inside the passage of the removed drainage is fixed inside the cavity and is partially preserved inside the passage of the wound channel after the drainage system is removed. The remaining clots prevent insertion of a new drainage strictly along the old wound channel, it may be infected and promote inflammatory process inside the wound channel, decelerating the healing of the cavity and the wound channel. In such cases in order to obtain prolong drainage of cavities an old drainage is removed after it has been obturated with fibrin clots and a new drainage system is installed, using a new wound channel. Several problems arise here. Firstly, it is impossible to lead a new drainage along a new passage strictly to the spot where the end of the old drainage was, thus making the process of cavity&#39;s draining inadequate. Secondly, formation of a new wound channel will further traumatize the tissues and may provoke generalization of the infection inside the drained cavity. Thirdly, the presence of fibrin clot inside the old wound channel will promote the inflammatory process inside it. 
     The appliance for drainage of cavities through skin is known [V. G. Ivshin An appliance for drainage of cavity formation via skin//Surgery—1998.—No 8.—p. 49-50.], this appliance presents a needle with an external cannula, installed non-stationary upon it and drainage to be inserted into the drained cavity along a new wound channel, supervised by ultrasonic testing. 
     The drawback of this system is impossibility of its insertion along the old wound channel and the necessity to use expensive and technically complicated equipment. 
     Another design includes drainage tube [A. M. Moroz Drainage tube with centimeters points//Clinical surgery.—1969.—No 5—p. 35.], which presents a spherically closed end of children stomach pump. Before application all necessary holes are made in the tube and it is inserted into the desired depth. According to its author this tube can easily be substitutes, by means of a metal mandrel. 
     The main drawback of the drainage tube of such design is the absence of a butt hole, thus making the process of drainage ineffective. It is not possible to reinstall the drainage, using a mandrel, as specified by the author. 
     A model of a drain tube, functioning for a long time is also known [V.I. Shaposhnikov—A design of a drainage tube of a prolong action//Vestnik Khirurghii (Messenger of Surgery).—2002.—No 5—p. 81-83.], it was chosen as prototype which specifies the possibility of regulating the permeability of drainage by inserting a bead fixed on a fishing line, both ends of the line are drawn outside. By means of constant drawing of the bead backwards and forwards along the tube&#39;s body constant destruction of fibrin clots, precipitated into the drainage passage is performed, due to traction on the line&#39;s ends. The authors also specify periodic shift of the drainage system alongside its length, within 1-2 cm, 4-6 times a day. 
     The drawback of this design, chosen as a prototype is the necessity of location of both ends outside, thus making it impossible to apply it in the bulk of clinical situations, when drainage has to be inserted from one side only. Besides, the drained cavity may get infected when the bead is moved, through a piece of fishing line that was led outside. An organizational difficulty of application of such type of drainage that supposes constant bandaging (up to 6 times a day) may be considered another drawback. 
     The present invention solves the problem of ensuring the possibility of removing the clot inside the drainage opening, but fixed by one end inside the wound cavity during the drainage removal, as well as ensuring the possibility of reinstallation of the drainage with smaller inside diameter, strictly along the old wound channel, irrespective of length and direction of the latter. 
     SUMMARY OF THE INVENTION 
     The problem set is solved by fixing an additional tube of smaller diameter with an opening on a tube draining along its entire length, and upon the working end of drainage a unit for clot&#39;s destruction is installed, consisting of a cylindrical body, a tube with an opening, an opening, corresponding to an opening of an additional drainage tube and a spring with a splitter, located inside the body, the drainage having a working head with a diametrically located line inside it, connected by means of thread with the body of the splitter, besides inside the wall of the tube drainage and the splitter&#39;s unit a channel is made, inside of which there is a fixing unit of the splitter, the working end of which is inside the body of the splitter&#39;s unit and it fixes the splitter, while its opposite end is drawn to the outside surface of the drainage through the aforesaid channel and is equipped with a ring. The body of splitter&#39;s unit has an internal growing-through from on one side and an external growing-through from the other side, it is also equipped with internal thread on the side of the internal growing-through for ½ of its length, while the diameter of the body in the spot of the external growing-through is equal to the internal diameter of the tube drainage. The channel of splitter&#39;s fixing unit, inside the tube drainage and the channel of splitter&#39;s fixing unit inside the wall of the body of clots&#39; splitting unit are located on the side, opposite to the place of fixation of an additional tube and the tube of the splitter&#39;s unit respectively, the channel of splitter&#39;s fixing unit, inside the body of the splitter is opened with an internal opening upon the surface of ledge&#39;s ring, formed by the difference between the diameter of the internal growing-through and the internal diameter of the body. The external diameter of the spring is equal to the internal diameter of the splitter&#39;s unit, while the diameter and the height of the fixing unit of the spring are equal to the width and depth of the body&#39;s slot, respectively. Clots&#39; splitter is fixed to the spring in such a way, so that its axis is located at 90° angle with regard to the axis of the spring&#39;s fixing unit&#39;s, the protruding end of clots&#39; splitter corresponds to the width of ring&#39;s ledge, formed by the difference between the diameter of the internal growing through and the internal diameter of the body, there being a possibility of its turning inside the body at the level of internal growing-through. The working head is made with an external growing-through, equipped with external thread for internal thread of the unit of clots&#39; splitter, the length of the external growing-through being equal to ½ of the length of the internal growing-through of the unit of clots&#39; splitter. The conductor is equipped with a plate and a handle and it has the working and directing ends, both ends being round in shape, while the conductor&#39;s plate is installed at 1.5-2.0 mm distance from the butt of the directing end of the conductor. The external surface of the tube drainage possesses slots with latches for the conductor and the fixing element of the splitter, respectively. 
     The novelty of this design is in the fact that the device ensures permeability of the wound channel after drainage is removed by means of clots removal from the drainage opening, clots being fixed by one end inside the wound&#39;s cavity, and by fixing such clots inside drainage. The new drainage may be reinstalled into the drained cavity strictly along the previously formed channel up to the healing of the latter. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The essence of the presented technical solution is illustrated with the drawings, where: 
         FIG. 1  presents the longitudinal section of the drainage system, 
         FIG. 2  presents the side view of the drainage, 
         FIG. 3  presents the longitudinal section of the tube drainage, 
         FIG. 4  presents the front view of the tube drainage, 
         FIG. 5  presents the back view of the tube drainage, 
         FIG. 5   a  presents the cross section view of the tube drainage  5   a,    
         FIG. 5   b  presents the cross section view of the tube drainage  5   b,    
         FIG. 6  presents the upper view of the tube drainage, 
         FIG. 7  presents the bottom view of the tube drainage, 
         FIG. 8  presents the side view of the tube drainage, pictured from the side of the slot of the splitter&#39;s fixing element, 
         FIG. 9  presents the side view of the tube drainage, pictured from the side of the slot of the conductor, 
         FIG. 10  presents the cross section view of the cylinder of the clots&#39; splitter unit, 
         FIG. 10   a  presents the view of the cylinder of the clots splitter unit in  10   a  section, 
         FIG. 10   b  presents the view of the cylinder of the clots splitter unit in  10   d  section, 
         FIG. 10   c  the view of the cylinder of the clots splitter unit in  10   c  section, 
         FIG. 11  presents side view of the cylinder of the clots splitter unit, 
         FIG. 12  presents the top view of the cylinder of the clots splitter unit, 
         FIG. 13  presents the bottom view of the cylinder of the clots splitter unit, 
         FIG. 14  presents the front view of the cylinder of the clots splitter unit, 
         FIG. 15  presents the back view of the cylinder of the clots splitter unit, 
         FIG. 16  presents the view of the spring with the clots splitter in longitudinal section, 
         FIG. 17  presents the side view of the spring with the clots splitter, 
         FIG. 18  presents the top view of the spring with the clots splitter, 
         FIG. 19  presents the front view of the spring with the clots splitter, 
         FIG. 20  presents the cross-sectional view of the working head, 
         FIG. 21  presents the side view of the working head, 
         FIG. 22  presents the front view of the working head, 
         FIG. 23  presents the back view of the working head, 
         FIG. 24  presents the cross-sectional view of the conductor, 
         FIG. 25  presents the side view of the conductor, 
         FIG. 26  presents the back view of the conductor, 
         FIG. 27  presents the splitter&#39;s fixing element in longitudinal section, 
         FIG. 28  presents the side view of the splitter&#39;s fixing element, 
         FIG. 29  presents the front view of the splitter&#39;s fixing element, 
         FIG. 30  presents the front view of the clots splitter&#39;s unit after the spring with the splitter were inserted into the cylinder of the clots splitter&#39;s unit, 
         FIG. 31  presents the front view of the clots splitter&#39;s unit at the moment when the splitter is turned in a counter-clockwise direction, 
         FIG. 32  presents the front view of the clots splitter&#39;s unit after the splitter was turned and was fixed anew by the protruded fixing element, 
         FIG. 33  presents the front view of the drainage with installed working head, after the splitter was turned and was fixed anew by the protruded fixing element, 
         FIG. 34  presents the front view of the clots splitter unit, pictured at the moment, when the splitter is returned into the previous position, after removal of the splitter&#39;s fixing element, 
         FIG. 35  presents the front view of the drainage with the working head installed after the clots splitter was returned into its previous position, 
         FIG. 36  presents the general view of the drainage, disassembled, in its isometric view. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     All drawings bear the same numbers for: 
       1 —the tube drainage;  2 —an additional tube;  3 —the unit of clots splitter;  4 —the working head;  5 —the conductor;  6 —the fixing element of the splitter;  7 —the working end of the tube drainage;  8 —the drainage openings;  9 —the opening of the additional tube;  10 —splitter&#39;s fixing element&#39;s channel inside the wall of the tube drainage;  11 —the opening of the channel of the splitter&#39;s fixing element on the external surface of the tube drainage;  12 —the opening of the channel of the fixing element in the butt of the tube drainage;  13 —fixing plates;  14 —holes, made in fixing plates;  15 —the slot for the conductor, made on the external surface of the tube drainage;  16 —the slot for the clots splitter&#39;s fixing element, made on the external surface of the tube drainage;  17 —growing-through of the additional tube, corresponding to the slot for the conductor;  18 —the latch, installed in the slot for the conductor;  19 —the latch installed in the slot for the fixing element of the splitter;  20 —the body of the clots splitter unit;  21 —the tube of the clots splitter unit;  22 —the opening in the tube of the clots splitter unit;  23 —the internal growing-through of the clots splitter unit;  24 —the internal thread of the internal growing-through of the clots splitter unit;  25 —the external growing-through of the clots splitter unit;  26 —the slot of the clots splitter unit;  27 —the channel of the splitter&#39;s fixing element, made inside the wall of the body of the clots splitter unit;  28 —the opening of the channel of the body of the clots splitter unit from the side of the growing-through;  29 —the ring of the ledge, formed by the difference between the diameter of the internal growing through and the internal diameter of the body of the clots splitter unit;  30 —the opening in the channel of the body of the clots splitter unit; pictured from the side of the external growing-through;  31 —the spring;  32 —clots splitter;  33 —spring&#39;s fixing element;  34 —the protruding end of the clots splitter;  35 —the beveled end of the working head;  36 —the external growing-through of the working head;  37 —the external thread on the external growing-through of the working head;  38 —the rod of the working head;  39 —the conductor&#39;s working end;  40 —the leading end of the conductor;  41 —the conductor&#39;s plate;  42 —the conductor&#39;s plate handle;  43 —the working end of the splitter&#39;s fixing element;  44 —the splitter&#39;s fixing element&#39;s ring;  45 —direction of turning of the clots splitter, when it is transferred into the working position;  46 —direction of turning of the clots splitter after the splitter&#39;s fixing element is removed. 
     The presented drainage design (See  FIG. 1-9 ,  36 ) consists of the tube drainage  1 , an additional tube  2 , fixed upon it, the unit of clots splitter  3 , the working head  4 , the conductor  5  and the splitter&#39;s fixing element  6 . 
     Six openings for drainage, of oval shape  8 , three on each side are made on the side surfaces of the tube drainage  1  ( FIG. 3 ) on the side of its working end  7 . Along the entire length of the additional tube  2  ( FIGS. 3-5   a ) an opening  9  was made. Inside the wall of the tube drainage  1  on the side opposite to the spot where the additional tube is fixed  2  a channel  10  of the splitter&#39;s fixing element  6  was made ( FIGS. 51 ,  5   b ), which is opened on one side by a hole  11  on the external surface of the tube drainage  1 , and by a hole  12  on the side of the working end  12  on the butt end of the tube drainage  1 . Two fixing plates  13  ( FIG. 5 ,  5   a ,  6 - 8 ) with two holes  14  in each are fixed on the external surface of the tube drainage  1 , on the side, opposite to the working end  7 . Besides the external surface of the tube drainage  1  has the slot  15  for the conductor  5  and the slot  16  for the clots splitter&#39;s fixing element ( FIGS. 5   b ,  6 - 8 ). The additional tube  2  also possesses growing-through  17  ( FIGS. 6 ,  9 ), corresponding to the slot  15  for the conductor  5 . The slot  15  for the conductor  5  has a latch  18  ( FIGS. 6 ,  9 ), and a latch  19  ( FIGS. 8 ,  9 ) is installed in the slot  16  for the splitter&#39;s fixing element  6 . 
     Clots splitter&#39;s unit  3  consists of a body  20 , a tube placed on its surface  21 , with an opening  22  ( FIGS. 10-15 ). The tube of the clots splitter&#39;s unit  21  is the continuation of the additional tube  2 , having the same diameter, while the opening  22  of the tube  21  of the clots splitter&#39;s unit  21  coincides with the opening  9  of the additional tube  2 . Besides, the body  20  has got on one side an internal growing-through  23  with internal thread  24  for ½ of its length. On the other side of the body  20  there is an external growing-through  25 , the external diameter of the body  20  in the area of the external growing-through  25  being equal to the internal diameter of the tube drainage  1 . A slot  26  is made on the internal surface of the body  20 , on the side of the tube&#39;s fixing  21 , while on the opposite side a channel  27  is made inside the wall of the body for the splitter&#39;s fixing element, being the continuation of the channel  10  of the splitter&#39;s fixing element, made inside the wall of the tube drainage. The channel  27  is opened by the hole  28  on the ledge&#39;s ring  29 , which is formed by the difference in the diameter of the internal growing-through  23  and the internal diameter of the body  20 . The channel  27  ends on the side of the external growing-through  25  with an opening  30 , the diameter of which is equal to the diameter of the opening  12  of the channel of the fixing element in the butt of the tube drainage  1 . The unit of the clots splitter also contains the spring  31  with clots splitter  32  and the spring&#39;s fixing element  33  ( FIGS. 16-19 ). The external diameter of the spring  31  is equal to the internal diameter of the body  20 , the length of the spring&#39;s fixing element  33  being equal to the height of the slot  26  of the body  20 . The length of the clots splitter  32  is bigger than the diameter of the spring  31  and it corresponds to the internal diameter of the body  20  in the area of the internal growing-through  23 . The axis of the clots splitter  32  is located at 90° angle towards the axis of the spring&#39;s fixing element  33 . The protruding end  34  of the clots splitter  32  ensures fixing of the spring in the necessary position, by means of the splitters fixing element  6 . 
     The working head  4  ( FIGS. 20-23 ) presents a body with one end beveled at 60° angle on one end  35  and the external growing-through  36 , made on the other end, having external thread  37  for internal thread  24  of the internal growing-through  23  of the body  20 . 
     The end beveled at 60° angle  35  of the working head  4  ensures minimal injuring of tissues by the end of the drainage system, installed during an operation and it also minimizes traumas, caused to the wound channel, when a new drainage is inserted. The maximal external diameter of the working head  4  is equal to the external diameter of the tube drainage  1  and its internal diameter is equal to the internal diameter of the tube diameter  1 . The external diameter of the working head in the area of the external growing-through  36  is equal to the internal diameter of the body  20  of lots splitter in the area of its internal growing-through  23 . Inside the working head  4  a rod  38  is installed diametrically on the side of the external growing-through. 
     The conductor  5  ( FIG. 24-FIG .  26 ) presents a flexible rod of a round cross section, made of dense, elastic material and possesses a working end  39  and a leading end  40 . Both ends are rounded. The rounded working end  39  eliminates the possibility of tissues injury, when drainage is replaced. The plate  41  is fixed on the conductor on the side of the leading end  40 , a handle  42  being mounted on it. The diameter of the conductor  5  is equal to the internal diameter of the additional tube  2  and the internal diameter of the tube of the clots splitter&#39;s unit  21 . The plate&#39;s thickness  41  of the conductor  5  is equal to the width of an opening  9  of the additional tube  2  and an opening  22  of the tube  21  of the clots splitter&#39;s unit, while the plate&#39;s  41  height and width correspond to dimensions of the lot  15 , made on the body of the tube drainage  1 . 
     The splitter&#39;s fixing element  6  presents a flexible rod of a round cross section, it is made of a dense and elastic material its working end  43  has a flat butt ( FIG. 27-FIG .  29 ). A ring  44  is fixed on the opposite end of the fixing element  6 . 
     The drainage system and its elements may be made of the following materials: tubical drainage, additional tube made from medical silicone, block for clot cutting, working head, conductor, holder of cutter, cutter is made from medical steel. 
     The drainage works in the following way. Before a surgical operation drainage is put into the working state. For this purpose a body of the clots splitter&#39;s unit  20  is inserted into the tube drainage on the side of its working end  7 . The uniform diameter of the external growing-through  25  of the body  20  the clots splitter&#39;s unit and the internal diameter of the tube drainage  1  ensure their dense contact and fixing of the body  20  in the tube drainage. The body  20  being orientated in such a way, so that an opening of the additional tube  2 , fixing on the tube drainage should coincide with the opening of the tube  21  of the clots splitter&#39;s unit and the opening  12  of the channel  10  of the splitter&#39;s fixing element, made inside the wall of the tube drainage should coincide with the opening  30  of the channel  27  of the body. A spring  31  is inserted into the body  20  in such a way, so that the spring&#39;s fixing element should pass into the slot  26  of the clots splitter&#39;s unit. The clots splitter  32  here will be located inside the body  20  on the level of the internal growing-through  23  of the body (See  FIG. 30-FIG .  35 ). Through the opening  11 , made on the external surface of the tube drainage  1  a fixing element of the splitter  6  is inserted and it is passed to the wall of the tube drainage through the channel  10  and channel  27 , made inside the body up to the level, when the working end  43  of the fixing element is on the level of the opening  28  of the body&#39;s channel on the side of its internal growing through. Clots ( 32 ) splitter  45  is turned by 270° angle in a counter-clockwise direction. The protruding end of the splitter  34  should be located behind the opening  28  of the body&#39;s channel. Holding the clots splitter  32  in such position, the splitter&#39;s fixing element  6  is moved in such a way, so that its working end  43  should keep the protruding end  34  of the splitter  32  in that position. 
     A working head  4  is inserted into the body  20  so that the thread  37  of the external growing-through of the head  36  should combine with the internal thread  24  of the internal growing-through  23  of the body. The 4 is turned in such a way, so the rod  38  of the working head  4  should be placed parallel with the clots splitter  32 . The splitter&#39;s ring  44  is turned, so that it will go into the slot  16 , made on the external surface of the tube surface. By placing the splitter&#39;s ring into the slot  16  a stable position of the working end of the fixing element  43  is ensured and consequently clots splitter  32  can be kept reliably in the desired position. 
     The splitter&#39;s ring  44  is kept inside the slot  16  by means of a latch  19 . Then a conductor  5  is inserted into the gap of the additional tube  2 , from the side of the opposite head and it is led throughout the entire additional tube  2  and the tube  21  of the unit of clots splitter. The conductor&#39;s plate  41  being led through the opening  9  of the additional tube and is to be placed opposite to the growing-through  17  inside the additional tube  2  and slot  15 . After that the conductor&#39;s plate  41  is turned and inserted into the slot  15 , where it is eventually fixed with a latch  18 . The location of the plate  41  in the slot  15  eliminates the possibility of distortion of the working end during the process of prolong staying of the drainage, thus guaranteeing the precise location of the end of the following drainage installation, which will replace the old one through the conductor  5 . Now the drainage is ready for work. The described preparation of drainage can be performed at a plant. 
     A set of drainage installations, of the design, described here, of equal length with different diameter of tube drainage  1  and the body  20  of the splitter&#39;s unit. The diameter of the additional tube  2  and the tube  21  of the clots splitter&#39;s unit and also the diameters of the channel  10  of the conductor&#39;s fixing element in the tube drainage  1  and the channel of the clots splitter&#39;s fixing element in the splitter&#39;s unit are equal for all drainage procedures. Only the first drainage set is supplied with the conductor  5 . 
     Drainage is used in the following way. After the surgical operation drainage is inserted into a cavity, which needs to undergo drainage. Drainage is fixed to skin by means of the openings  14 , made in the fixing plates  13 . Aspiration is carried out in an active or passive way both through the side openings  8  and through the opening in the working head  4 . After the drainage system has completed its work due to its obstruction with a clot or a piece of tissue, the system is replaced with a drainage set of smaller diameter. To perform it is necessary to remove drainage coupling to skin, after that the ring  44  of the splitter&#39;s fixing element is removed from the slot  16  and by traction through the ring  44 , the fixing element  6  is removed from the drainage. This results in the spring&#39;s  31  returning to its original location. The clots  32  splitter  46  is turned by 270° angle in a clockwise direction. As the result the clot is cut out between the splitter  32  and the head&#39;s rod  38 . After the turning the splitter is located perpendicular to the axis of the head&#39;s rod  38 , thus making it possible to retain the cut out clot inside the drainage opening. The conductor&#39;s plate  41  is removed from the slot  15  using the plate&#39;s handle  42 , after which, holding the conductor in its previous position, the drainage is removed from the cavity by means of the handle  42 . Then the leading end  40  of the conductor  5  is inserted into the opening of the tube  21  of the splitter&#39;s unit of the new drainage set with smaller diameter of the tube drainage and the new drainage is led up to the level where the old drainage has stood, along the conductor  5 . The rounded shape of the leading end  40  facilitates its insertion into the tube&#39;s opening  21 . The conductor  5  first passes inside the tube of the splitter&#39;s unit  21  and then inside the additional tube  2  up to the level of the growing-through  17 . After that the conductor&#39;s plate  41  is turned and it is placed into the slot  15 , where it is fixed by means of a latch  18 . a new drainage set is coupled to the skin through the openings  14  in the fixing plates  13 . Then the cavity undergoes drainage. In case of necessity the new drainage set is replaced by the subsequent sets of smaller diameters, using the methods described above. After the cavity has become smaller, as well as the diameter of the wound channel it may be possible to leave only the conductor  5  inside, which could be used for subsequent insertion of drainage a few days later. In case the conductor  5  is remained in the cavity it is to be fixed to the skin through the handle  42 . Besides, in case the drainage has to stand for a long time it is possible to replace the conductor  5 , prior to the removal of the last drainage.