The present invention generally relates to a method and an apparatus to collect and/or convey various types of liquids, to be stored air or gas free in a closed package or receiver or to be directly led into another receiver. The invention is useful, among other things, for handling of blood, whereby the collected blood can directly be returned to the blood system of living human beings or animals without any contact with human hands and without any risk of contamination during the operation and preferably under sterile conditions. The invention can be used when handling various types of liquids and for many purposes, particularly when handling liquids, which tend to foam when handled, liquids which contain not desirable or harmful particles or impurities, or liquids which become damaged, oxidize or gelify etc. when the liquid comes into contact with the air or the gas. The method and the apparatus can be used e.g. when food-stuffs such as milk, cream, oils, fruit drinks, juices etc. are handled, when oils and corrosive or environment-hazardous liquids of various types are handled, when it is important that the liquid will not come into contact human skin or be discharged into the environment or into drains, when blood is handled in connection with medical surgical operations, when various types of waste liquors etc. are sucked. The invention has been developed particularly in connection with handling of blood, and it will in the following text mainly be decribed in connection with such a handling. Blood is always a liquid in short supply and large amounts of blood are used during blood transfusions, e.g. in connection with surgical operations. Blood is

expensive to collect, to test as well as to store. There is also a risk of transmission of jaundice, HIV- infection and other diseases during blood transfusions. In connection with certain operations the patient may lose large quantities of blood, sometimes as much as several liters. This blood normally is wasted and the patient has to receive the corresponding amount of blood through transfusions. Attempts have been made in different ways to solve the problem of supplying blood. There are e.g. methods of purifying and anticoagulation-treating blood, which has been partially coagulated, but these methods are expensive and time- consuming, and the transfusion product is inferior. Also, autotransfusions are used now, whereby a patient is letting his own blood as a blood-donor a few weeks before a planned operation, and said patient, in case a need arises, having his own blood restored during or subsequent to the operation. However, this method needs planning and cannot be applied when emergency operations are needed. Normally, the patient also must be reasonably healthy, when he is a blood-donor, and equipment for possible purification, catalogueing and storage of the patient's blood is required in the actual localities. This method has so far only been rarely used. The object of the invention therefore is to make it possible to collect the blood of a patient, and in case of need of blood transfusion, in the first plact, to return the patient's own collected blood to him or the blood which he bleeds from his blood vessel system after a tissue injury and/or during the surgical operation (autologuous transfusion). Three main problems arise when doing this: - when blood is sucked from a wound surface, large amounts of air or another gas or gas mixture inevitably are sucked jointly with the blood, which results in an air/gas admixture with a strong frothing, which like the contact of the blood with foreign substances and free air or gas contributes to an initiation of the coagulation system activation of the blood; - air/gas and froth (foam) will be dominant for the content of the storage unit, which accelerates the coagulation and besides prevents a direct returning of the blood to the patient, both due to the air contents itself and also due to the fact that the enzyme system and the cells of the blood are activated by the interface between blood and air bubbles; - the collected material may contain not desirable tissue fragments from the operation wound (clots, muscle particles, fat, bone etc.), which activate the enzyme system of the blood; this activation as well as the admixture of not desirable and in this connection dangerous tissue fragments prevent a direct

return of the collected blood to the patient. The above-mentioned problems can be solved according to the present invention by a method and a device, by means of which the patient autologuously can be given blood in that - the blood which disappears or has disappeared is suction collected during or after the surgical operation; - the blood/air/gas mixture is brought, in a closed system, to pass a defoaming and separation filter, in which the blood froth is disintegrated and not desirable particles are separated, whereas the blood is allowed to pass; - the blood flows into a receiver, in which the blood is allowed to slowly flow downwards along e.g inclined planes or along the walls of the receiver mounted in the receiver, whereby air bubbles included in the blood are allowed to escape to the upper part of the receiver; - the blood is collected in the lower part of the receiver, which in its bottom is provided with a manually or automatically operating valve, which is being opened or opens up resp. when a certain amount of blood has been collected at the bottom of the receiver, the blood flowing into a collecting vessel or is directly returned to the blood system of the patient, said valve is being closed or closes resp. again when the blood level in the lower part of the receiver has been lowered to such an extent, that there may be a risk that air and gas will follow the blood into the collecting vessel; and - the collection of the blood in the vessel is done entirely without any admixture of air or any other gas by means of a certain negative pressure, which acts on a completely air-void flexible container, and the suction of air from the upper part of the receiver is done by means of a suction system with a pressure, wich is higher than the pressure on the flexible (or elastic) collecting container; - the sucked blood/air/gas-mixture may automaticly and in proportion to the amount of sucked blood be given an admixture of an anticoagulant agent, e.g. , a citrate of a type which is active and known per se, controlled by a differentiated pressure in the system, whereby the pressure in the anticuagulant apparatus is lower than the pressure of the defoaming and separation filter means and of the blood recipient. Characterizing features and advantages of the present invention will be set forth in the following detailed description of an embodiment of the invention, which is illustrated in the accompanying drawings.

In the drawings Fig. 1 shows diagrammatically and substantially simplified a device designed to carry out the method according to the invention, shown before the device is used to collect a liquid. Figures 2 and 3 show two alternative embodiments of a defoaming and collection apparatus included in the device according to figure 1. Figure 4 shows the device according to Fig. 1 in operation during the liquid collecting. Figure 5 shows a device of the same type as that of figure 1 but formed with means for automatically supplying an additive to the sucked liquid at a stage before the suction operation starts. Figure 6 shows the device of figure 5 during the function of sucking liquid, and figure 7, finally, diagrammatically shows a further alternative apparatus for defoaming/deaerizing the liquid and for dozing of an anticuagulant. The device shown in Fig. 1 comprises five main parts, which operate with a certain pre-set pressure gradient, namely a main negative pressure P3 (suction), which acts on some of the parts, and a certain higher pressure P2 (relatively lower suction action), which acts on other parts of the device, which will be explanied in the following text, as well as a third still higher pressure PI , which can be the atmospheric pressure and at which the liquid or the liquid/air/gas mixture is sucked into the device. The main parts of the device have in Fig. 1 been indicated as blocks with dashed lines, although the parts can be competely or partially integrated to a continuous disposable device. The parts are as follows: 1) a suction system with a a pilot valve and a manometer or pressure gauge, designed to provide both a negative pressure with a lower pressure level P3 and a higher pressure level P2 and connected to the various parts of the device by means of conduit systems and designed to provide a suction action from an area having a still higher pressure PI ; 2) a suction nozzle designed to suck a liquid at an atmospheric or normal pressure PI, preferably atmospheric pressure or normal pressure PI , and which is influenced by said relatively high pressure level P2; 3) a separation and defoaming filter, which is connected to the suction nozzle 1 and which is influenced by the relatively higher pressure level P2; 4) a receiver with inclined planes and with a bottom valve for draining the liquid and operated by a pressure of said higher pressure level P2; 5) a system having one or more collecting vessels and directly connected to the receiver 4 and operated by a pressure of said lower pressure level P3 and having means for emtying the collection vessel or vessels or means for directly transferring liquid from one receiver to any other means, e.g.

returning the liquid to a patient. The suction system 1 comprises a tube or hose 7 which is connected to a suitabl negative pressure source P3 (not shown), which can be any conventional or available negative pressure source or which can be an air ejection pump or the like. Conduit 7 is through a first branch conduit 9 connected to a certain part of collecting vessel 5 and through a second branch conduit 10 to de-air receiver 4 via choke/pilot valve 11 , which chokes the gas flow in this branch conduit and consequently also in receiver 4 to a predetermined extent, i.e. to obtain a higher pressure P2 (suction action lower) in receiver 4 than in those parts which are influenced by pressure P3. In order to be able to preset and read pressure gradient P2-P3 a manometer or pressure gauge 12 is connected between the conduits 9 and 10 having pressures P3 and P2 respectively. In the illustrated case the manometer is a water seal manometer, the pressure gradient being measured in mm water column, but it can just as well be any type of manometer or water gauge as shown in figure 7. Pressur gradient P2-P3 is controlled by setting the pilot valve and is adjusted in such a way, read on the water seal or the manometer, that an automaticly operating outlet valve which can be connected in the bottom of the receiver 4 normally is closed and opens up only when a certain liquid volume is obtained in the lower part of receiver 4 and closes before the liquid level in the receiver has decreased so much that a risk exists that air or another gas or gas mixture will pass the valve. The upper and the lower limits of pressure gradient P2-P3 is a very important factor for the function and the safety of the device. The water seal or a similar device used instead is a guarantee for a reliable control of pressure gradient P2-P3. The artisan knows very well that the two different negative pressures P3 and P2 respectively alternatively can be obtained from two external negative pressure sources for the different pressure levels, pilot valve 11 being left out and pressure P2 of the higher pressure level being propagate directly into conduit 10 to venting receiver 4. Suction mozzle 2 can be any known nozzle, designed to suck a liquid in the open air or in any other gas or in a gas mixture. The nozzle in the embodiment shown in figure 1 is connected to venting receiver 4 via separation and defoaming filter 3 and acts with pressure P2, possibly reduced to some extent due to the restriction, which may exist in filter 3. Figures 2 and 3 show two alternative embodiments in which the defoaming filter 3 is formed integral with de-air recipient 4.

Separation and defoaming filter 3 comprises a closed container 13 with a filter insert 14 mounted therein of a type which is capable of both filtering off particles, tissues etc. from the liquid and also is capable of disintegrating foam by separating air from blood in the foam, whereby the liquid passes through the filter. Filter inse 14 divides up the container into two parts, an upper container part 15, designed to collect foam and particles and a lower part 16, from which the liquid flows to de-a receiver 4. Suction nozzle 2 leads to upper container part 15, and an outlet or connection tube 17 from lower container part 16 leads to receiver 4. Filter 13 suitably is mounted slightly downwardly inclined towards outlet tube 17. Higher pressure P2 acts in filter 13 and is transmitted via connection tube 17 from the upp part of receiver 4. The de-air recipient 4 comprises a closed container 24, in the upper part of which the connection tube 17 for the liquid opens, and which is formed with any type of a plane along which the liquid can flow, e.g. a system of inclined planes 25 as shown in figure 1 along which the liquid or liquids are allowed to flow slowly downwards whereby the air which is admixed in the liquid is given the possibility o leaving to the upper part 26 of the unit 24. The inclined plane can be a system of inclined plates or a spiral-shaped track or preferably it is a helical tube or a helicall arranged flexible hose having such a dimension that the liquid medium fills a portion of the cross-section, the air having a chance to escape upwards. Also, it i posible to lead the liquid towards the walls of the receiver and thereby let it flow downwards along said walls. It is also possible that the air is allowed to leave the liquied after the liquid has been colected at the lower part of the recipient 24. In the upper part of the container branch conduit 10 also opens, which constitutes an achaustion tube for air, which can escape directly outwards through pilot valve 11 and suction hose 7. In the bottom of receiver 24 there is a valve, which can be a manual valve of an automatically operating valve. In case the liquid will be directly transferred to another liquid system, the valve can be a manual valve and can be connected to a hose or a conduit 31a. An automatically operating valve can comprises a valve seat 27, in which a valve cone of any type is seated, in the illustrated case a displacement valve ball 28. Valve ball 28 is designed with such a mass and such a lifting force in relation both to the pressure P2 in the evacuation conduit 10 and also the pressure P3 from from the outlet 31 of the receiver 24, that it will open up, when a certain amount of liquid column has been collected on the bottom of the receiver and will close, before the

liquid column has been drained completely. Thereby the risk is eliminated that air will be sucked through the valve seat and into the hose of the liquid system, e.g. th patient, or into the collecting container or containers 5. The valve alternatively can be an electrically, pneumaticly or hydraulicly actuatable stop valve, which is operationally connected to an electric, optical or capacitive level sensor, which is mounted inside or outside the receiver and which opens up and closes the valve for a certain predetermined high and low respectively liquid level in the receiver. Such an apparatus is diagrammatically illustrated in figure 7. In the illustrated case the device, as an alternative to the hose 31a for directly transmitting the liquid to another liquid system, is designed with two liquid containers 29 and 30, connected in parallel, which are identical and connected to receiver 4 through a drain conduit 31 , which starts at valve seat 27. Each liquid container contains a flexible bag 32, which is enclosed in a shape- permanent casin 33. Bag 32 is with its upper part directly connected to drain conduit 31 via a branch conduit 34, 35 with stop valve 36, 37. The lower part of bag 32 has a drain condui 38 with a stop valve 39. The shape-permanent casing 33, which stands under pressure P3, is connected to branch conduit 9 via a stop valve 40, which when it is opened up give the space between casing 33 and bag 32 the lower pressure P3 and thereby causes a suction action on the bag and a suction downwards of liquid from receiver 5, when its bottom valve 28 is opened up. Shape-permanent casing 33 has second tube joint 41 with a stop valve 42 in order to give the space between casing 33 and bag 32 a positive pressure in order to remove all the air from bag 32, which in Fig. 1 is shown in its flat compressed air-void condition, which is the starting point for liquid suction. Figure 2 shows a combined defoaming an de-air apparatus, in which a defoaming unit 13' with a separation filter 14' is mounted inside the de-air receiver 24' . The filter is formed as a cone which is widened in the direction downwards, and in which the filter 14' forms the upper part of the apparatus and is sealingly connected to the walls of the receiver 24' , and in which the walls of the chamber 16' formed underneath the filter 14' is shaped like a kind of sub- cone 43 the outer periphery of which is located on a slight distance from the receiver walls, so that liquid, which flows down along the sub-cone, is guided along the walls of the receiver 24'. In this case the liquid is sucked directly into the chamber 44 above the filter 14' through a conduit 45 from the suction nozzle. The de-air conduit 10' open at the top of the sub-cone 32.

Figure 3 shows a still alternative embodiment of a combined defoaming and de air unit in which the filed is formed as a upright filter cylinder which is mounted concetrically inside the de-air receiver, and in which the liquid, e-g- the blood, enters through a conduit 45 in the inner chamber 44" of the filter cylinder 14" . Th de-air conduit 10" is, like the drain conduit 31", mounted in the outer chamber 46 utside the filter 14", and the liquid is sucked through the filter 14" and into the out chamber 46, from which the liquid is drained through the conduit 31". The air is evacuated through the de-air conduit 10" . Fig. 4 shows the device of Fig. 1 in operation when used to suck a liquid, e.g. blood, through suction nozzle 2. The function is as follows: Suction hose 7 is connected to a source of negative pressure P3, which pressure is propagated through branch conduit 9 to the collecting vessel 6. Via pilot valve 11 a higher pressure P2 (less suction) is propagated to receiver 5 and via the latter also through separation and defoaming filter 3 to suction nozzle 2, in which a pressure is obtained, which is at least approximatively the same as pressure P2. Valve 36 to the one container bag 32, the left bag in the drawings, is opened up and valve 40 to container casing 33 is opened up, whereby a pressure P3 being obtained between bag 32 and casing 33. Suction nozzle 2 is lowered towards or into the liquid to be sucked. The liquid must be influenced by a pressure PI , which is higher than pressures P3 and P2, and generally the liquid is influenced by the atmospheric pressure in the open air. Usually a mixture of air and liquid drops or a continuous liquid column is sucked into nozzle 2. In case nozzle 2 contains liquid, the free air stream through the nozzle is stopped and the pressure decreases (the suction action increases) in hose 45 to filter 3, and this means that pressure P2' is so much less than the counter pressure P3 in the flexible receiver bag 20 that the liquid, e.g. blood, flows into the separation and defoaming filter 3, which which tissue particles, e.g. coagulumm muscle particles, bone particles and fat etc. is separated on the upper surface of the filter 14, and on which surface also blood foam is desolved, which foam may have been formed during the passage of the air/liquid mixture through the suction nozle 2 and the conduit as far as to the filter 13 whereas the liquid passes ghrough the filter 14 and is passed into the reciever 4 through conduit 17. The liquid is then allowed, due to its own gravitation, to slowly flow downwards along the inclined plane(s) 25 or along the walls of the receiver 24, the air which has come along with the liquid into receiver 4 and the air bubbles which are included in the liquid being allowed to be separated. The air escapes from the upper

part 26 of the receiver through de-air conduit 10, which is influenced by the highe pressure P2 and then out through suction hose 7. Liquid is collected successively i the lower part of the receiver 24, and when the liquid has reached a certain predermined volyme valve ball 28 is lifted and liquid is sucked downwards into container bag 32 through the influence of pressure P3 on container bag 32, which pressure is lower than pressure P2 in the receiver. When the liquid level in receiver 4 has been lowered to a predetermined level, set in order to prevent a stream of air into drain conduit 31 and container bag 32, valve ball 28 closes again, balanced both by the mass of the ball and also by pressure gradient P2-P3, and a new unit volume of liquid is collected in the same way at the bottom of the receiver. In case bag 32 in one of the liquid containers will be full, valves 36 and 40 are closed and the corresponding valves in the other, the shown right-hand liquid container are opened up, this second container being filled with liquid in the same way. Filled liquid bag 32 can be emptied into a handling bag, and the liquid be directly fed to the patient, possibly via a blood processor, or to a cold storage device, to be used at a later date. In many cases, for instance when a so called heart-lung-machine is used, the collected blood can with advantage be directly transferred from the receiver 4 to th vein reservoir of the machine and from this reservoir to the patient. Filled bag 32 in the collecting vessel can be emptied through gravitational flow, but the drainage can also be done by applying a positive pressure in the chamber between casing 33 and bag 32 via connection conduit 41. The apparatus shown in figures 5 and 6 is also formed with an apparatus 6 for dosing of any type of additives for the suction collected liquid, and said apparatus i fed with pressure of the lower presure level P3, i.e. the stronger suction, through the branch conduit 8 from the suction hose 7. The dosage material can be in the form of a liquid, a gel, a powder or in the form of granulas as long as said material can be sucked into and mixed with the sucked liquid, and it may for instance be an anti-oxidant, an anti-coagulant and/or a disinfectant for blood, an emulsifier for water and oil etc. The apparatus has two or more dosing units, connected parallelly or in series, in case is is desired to mix several different additives into the sucked liquid. The dosing apparatus is mounted at a position between suction nozzle 2 and filter 13 a dosage device 4, and on a higher level than suction nozzle 2 and filter 3, and it is connected to the conduit 45 between the suction nozzle 2 and the filter

through a connecting tube 18 having a pilot valve 19, by means of which the flow o dosage medium can be regulated. The dosage device comprises a flexible container or a bag 20, which is enclosed in a rigid casing 21, which via branch conduit 8 is influenced by lower pressure P3. Container 20 can be filled through a conduit 22 with a stop valve 23. The pressure between casing 21 and container 20 is lower than the pressure in suction nozzle 2, and the result thereof is that no dosage medium is sucked from the bag 20 into the suction nozzle until the pressure of the suctions nozzles is lowered, and said pressure is being lowered when when a liquid in drop form or in the form of a liquid column enters the nozzle and chokes a free entry of air into the nozzle. In this situation dosage medium enters the suction nozzle and is mixed with liquid. The amount of dosage medium sucked into the nozzle is, surprisingly, close to proportional to the amount of liquid sucked into the nozzle.

It ^' is assumed that pilot valve 19 to dosage device 4 in advance has been set in such a way, that low pressure P3 in dosage device 4 prevents dosage liquid from flowing into condiut between suction nozzle 2 and filter 13, in case the suction nozzle does not contain any liquid. When liquid is sucked into conduit between suction nozzle 2 and filter 3 pressure activity in this conduit is accordingly increased and this makes dosage agent in a certain amount in proportion to the amount of liquid sucked from suction nozzle 2 being sucked through the conduit 18 and further into filter 13. The device is then ready to be used. In the embodiment of the invention, in which the device is used to collect blood, the dosage medium can e.g. be a so called citrate solution, which, as the artisan knows, is used to bind the ionized calcium in the blood and in this way prevent the coagulation of the blood. The dosage medium also can be any other liquid agent or a mixture of agents having an active influence on the sucked liquid or designed to facilitate the disintegration of the foam or with any other functions. By admixing a disinfectant combined with a citrate solution also relatively stonrgly infected blood can be disinfected and can be reused. As is known, a contact with foreign substances such as walls in flowc conduits and apparatuses may activate the cells of the blood and it enzyme system, e.g. the coagulation system and the cells of the

blood, which will strongly and harmfully affect the quality of the blood. In order to eliminate these problems when treating blood by means of the described device it may be good - if considered necessary of preferable - that the walls in suction nozzle 2, filter 3, connection tube 17, de-air receiver 24 as well as on inclined planes 25 be provided with a coating of resistant heparin, which is capable of inhibiting the mechanisms, which activate the coagulation system of the blood as well as changes of or in the cells of the blood. Several heparinizing methods and similar methods are known, one of them being protected i.e. by European patent No. 86.186. In order to achieve a satisfactory result, when a citrate solution is dosed in blood, the dimensions of connection tube 18 of the citration device, in such a way, that citrate bag 20 doses an amount of citrate solution, which is equal to 10-20 % of the amount of blood, which flows into suction nozzle 2. The apparatus shown in figure 7 basically coincides with the apparatus shown in figures 5 and 6, and those parts of the apparatus which correspond to said earlier described apparatus have been given the same reference numerals with a prim-index ('). The latter apparatus structurally differs from the earlier apparatus in that the separation and defoaming filter 3 and the de-air recipient 4 are built integral to form a common unit. The anticoagulant from the dosing device is, in this case, collected in a funnel formed container at the upper side of the filter 14' , where the anticuagulant is mixed with the blood entering the container 13' tangentially like a cyclone. After having been filtered and defoamed the blood flows down along the walls of the container 13' and into several successive collection compartments 47 having overflow walls 48 before entering the drainage conduit 31. Figure 7 also shows that a valve can preferably be arranged close to the end of the suction nozzle 2 since it may happen that fragments get stuck at the inlet of the suction nozzle so that said nozzle becomes blocked. In order to prevent dosage medium from thereby entering the blood mixing portion of the apparatus it is important that the suction nozzle can easily be evacuated. As known the valve in the suction nozzle cas e.g. be formed as a finger hole in the nozzle tube as shown in a detail picture of figure 7.

REFERENCE NUMERALS

Part 4

24 container

25 inclined plane, spiral

26 upper part

27 valve seat

28 valve ball

Part 5

29 liquid container

30 liquid Container

31 drain conduit

32 bag

33 casing

34 branch conduit

35 branch conduit

36 stop valve

37 stop valve

38 drain conduit

39 stop valve (in 38)

40 stop valve (in 9)

41 tube connection

42 stop valve (in 41) 43 sub-cone

44 inner chamber

18 tube house (6 to 3) 45 suction house

19 pilot valve 46 outer chamber 0 container 47 collection compartment 1 casing 48 overflow wall 2 conduit 3 valve