Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
  • A61L2/00—Methods or apparatus for disinfecting or sterilising materials or objects other than foodstuffs or contact lenses; Accessories therefor
  • A61L2/02—Methods or apparatus for disinfecting or sterilising materials or objects other than foodstuffs or contact lenses; Accessories therefor using physical phenomena
  • A61L2/04—Heat
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F1/00—Treatment of water, waste water, or sewage
  • C02F1/02—Treatment of water, waste water, or sewage by heating
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F1/00—Treatment of water, waste water, or sewage
  • C02F1/02—Treatment of water, waste water, or sewage by heating
  • C02F1/04—Treatment of water, waste water, or sewage by heating by distillation or evaporation
  • C02F1/045—Treatment of water, waste water, or sewage by heating by distillation or evaporation for obtaining ultra-pure water

Definitions

• the present invention relates to a method and a device for sterilizing and dispensing a liquid for medical use.
• hemofiltration which is one of the treatments used to alleviate renal failure.
• Hemofiltration consists in extracting from the blood of a patient, by ultrafiltration, a determined quantity of plasma water and simultaneously infusing the patient with a lesser quantity of a so-called substitution solution, which is sterile and contains the main electrolytes. blood in respective concentrations identical to or close to that of the blood of a healthy patient. For a four-hour hemofiltration session, it is not uncommon to prescribe an exchange volume for which approximately sixteen to twenty liters of substitution solution must be available.
• peritoneal dialysis Another example of treatment that requires the use of a large amount of sterile fluid is automatic peritoneal dialysis.
• the principle of peritoneal dialysis which also aims to overcome the insufficiency renal, is to infuse into the peritoneal cavity of a patient a determined amount of a sterile solution containing an osmotic agent such as glucose as well as the main electrolytes of blood in respective concentrations close to those of the blood of a healthy patient .
• the solution thus perfused is allowed to stagnate in contact with the peritoneum, which behaves like a natural dialysis membrane, for the time necessary for the solution to enrich the impurities of the blood (urea, creatinine) in an optimal manner.
• the used solution added with the plasma water which the glucose made migrate in the peritoneal cavity is then drained out of the belly of the patient, then it is replaced by fresh solution.
• peritoneal dialysis In the classic peritoneal dialysis mode, called “continuous ambulatory peritoneal dialysis (CAPD)", it is the patient himself who performs the drainage and filling operations of his peritoneal cavity, by connecting a collection pocket or a pocket filled with solution at the end of a catheter installed permanently through its abdominal wall. The liquid is transferred from the peritoneal cavity to the collection pocket and from the solution pocket to the peritoneal cavity by gravity, the collection pocket being kept below the level of the abdomen and the pocket filled with solution. cool being kept above the level of the abdomen.
• a patient performs the drainage-filling operations which have just been described four to five times during the day and the exchange relates each time to two liters of liquid.
• peritoneal dialysis In the peritoneal dialysis mode called “automatic peritoneal dialysis (APD)", the drainage-filling operations are carried out at night, during the patient's rest, using a machine essentially comprising a pump for circulating the liquid spent and fresh dialysis solution, a heater to heat the fresh solution, a scale to weigh the pockets of fresh solution and used liquid and measure weight loss, and a programmable control unit to control the alternation of stagnation and drainage-filling cycles.
• APD automatic peritoneal dialysis
• the sterile liquids used for the implementation of medical treatments of the type of those which have just been mentioned are prepared industrially and are packaged in bags of flexible plastic material.
• this method of preparation has several drawbacks, in particular the cost of transporting and storing pockets of heavy and bulky solutions and the need to manage products. having expiration dates.
• devices have been proposed for preparing sterile medical liquids at the place of their use.
• the document EP 0 622 087 describes a process for the on-line preparation of a sterile and pyrogen-free liquid which is obtained by filtration of a dialysis liquid produced by a conventional dialysis machine.
• the document GB 2 034 584 describes a process for the preparation of a sterile liquid, the sterility of which is obtained by heating the liquid to a determined sterilization temperature for a determined time.
• a device for implementing this method which is designed to fill bags with the sterile liquid, comprises:
• - heating means for raising the temperature of a liquid immediately upstream of a sterilization unit constituted by a portion of insulated circuit
• a circuit connected to the sterilization unit having a first end connected to a source of liquid to be sterilized and a second end connected to a connector having a first outlet for delivering sterile liquid;
• This device further comprises means for degassing by heating the liquid to be sterilized upstream of the heating means and the sterilization unit in order to prevent the liquid from carrying bubbles during the sterilization treatment.
• sterility defines a microbiological quality of the so-called "sterile" object and that according to standard EN 556 as well as according to the American Pharmacopoeia and the European Pharmacopoeia, for a device or a liquid to be labeled sterile, it the theoretical probability of the presence of a viable microorganism in this device or liquid must be less than or equal to 10 " .
• An object of the invention is to provide a sterilization process and a device for implementing this process which make it possible to guarantee the sterility of the liquid prepared by the device according to the process. To achieve this goal, provision is made, in accordance with the invention, for a device for preparing a sterile liquid comprising:
• main circuit comprising:
• a first pipe having one end connectable to a source of liquid to be sterilized and another end connected to an inlet of the heating enclosure, and
• a second pipe having one end connected to an outlet of the heating enclosure and another end connected to a connector having a first outlet for delivering a sterile liquid
• the device further comprises control means for controlling the pumping means and / or the main heating means so that the calculated value of the parameter representative of the sterilizing value (F0) of the sterilization treatment applied to the second pipe and to the connector is greater than the threshold value F0min2 corresponding to the sterility of the second pipe and the connector.
• the device further comprises means for preventing the formation of bubbles in the liquid during the sterilization of the second pipe and of the connector, such as an adjustable opening valve for regulating the pressure of the liquid. at least one pressure value greater than the vaporization pressure of the liquid, whatever the temperature of the liquid, this valve being arranged on the first evacuation pipe.
• the device comprises means for validating a sterilization treatment applied to the liquid comprising calculation means for calculating a parameter representative of the sterilizing value (F0) of the sterilization treatment from the value at least one operating parameter of the device (Q, Tin, THin, All, THout), and comparison means for comparing the calculated value of the parameter representative of the sterilizing value (FO) at a threshold value FOminl corresponding to the sterility of the liquid.
• the calculation means are provided for calculating the parameter representative of the sterilizing value (FO) of the sterilization treatment applied to the liquid from a mathematical model of the distribution of the temperatures in the heating enclosure, of the temperature (Tin, All) of the liquid entering or leaving the heating chamber, the temperature of the heating liquid (THin) and the flow rate of the liquid (Q) in the heating chamber.
• FO sterilizing value
• the subject of the invention is also a method for sterilizing and dispensing a liquid comprising:
• FIG. 1 represents the diagram of a first embodiment of a device according to the invention
• FIG. 2 represents the diagram of a second embodiment of a device according to the invention
• Figure 3 is a perspective view of a first embodiment of a heat exchanger according to the invention
• Figure 4 is a perspective view of a second embodiment of a heat exchanger according to the invention.
• the device for preparing and dispensing a sterile liquid shown in FIG. 1 essentially comprises main heating means 80 having a heating enclosure 511 for the liquid, and a main circuit having a first pipe 1 connected to an inlet of the enclosure. heating 511 and a second pipe 2 connected to an output of the heating enclosure 511.
• the main heating means 80 comprise a reservoir 81 for a heating liquid (oil or ethylene glycol, for example) connected by a pipe 83 for recirculating heating liquid to a tubular jacket 512 which surrounds the heating enclosure 511 of the liquid to be sterilized.
• the heating chamber 511 and the jacket 512 form a first heat exchanger 51.
• the main heating means 80 further comprise an adjustable heating member 84 for heating the heating liquid, and a pump 42 for continuously circulating the heating liquid in the exchanger 51.
• the first pipe 1 has two inputs controlled respectively by means of two valves 20, 21: a first input is connected to a source of water (valve 20) and the second input is connected to a source of medical liquid (valve 21).
• the following members are arranged on the first pipe 1, in order from the valves 20, 21: a conductivity meter 85 for measuring the conductivity of the liquid in the circuit and for checking whether the liquid is water or a solution; a filter 86; a degassing chamber 87 provided with a level detector 88; a flow meter 74; a first pump 40; first additional heating means 501 and a valve 23.
• a drain pipe 3 which is provided with a valve 22 and a non-return valve 89, connects a high point of the degassing chamber 87 to the sewer .
• a bypass line 4 provided with a pump 41 is connected to the purge line 3 so as to bypass the valve 22.
• the second pipe 2 connects the outlet of the heating enclosure 511 to an outlet of the main circuit, which is constituted by a special sterilizable connector 90, having one entrance and two exits.
• a connector of this type is for example described in patent No. WO 96/05883.
• first additional cooling means 502 which are advantageously combined with the first additional heating means 501 to form a second heat exchanger 50
• main cooling means comprising a tubular jacket 521 surrounding the pipe 2 over a part 522 of its length to form a third heat exchanger 52, the jacket 521 having an inlet connected to a source of cold water by a supply pipe 5 on which is disposed a pump 43, and an outlet connected to the sewer by a discharge pipe 6 on which are arranged, in order from the exchanger 52, a valve 25 and a non-return valve 91 ;
• the first evacuation pipe 7 is used during the sterilization of the second pipe 2 and of the connector 90, and during the drainage of the peritoneal cavity of a patient, when the device according to the invention is used for the treatment of a patient by peritoneal dialysis.
• the following members are arranged on the first evacuation pipe 7, in order from the connector 90: two valves 28, 29 which are split for safety reasons; second additional cooling means 531; second means for adjusting the liquid pressure constituted by a valve 37 with adjustable opening, which a bypass line 8, provided with a valve 30, makes it possible to bypass; a non-return valve 92; a second flow meter 75; a blood detector 95; a valve 31.
• a bypass line 9 provided with a valve 32 and a second pump 44 is connected to the evacuation line 7 so as to bypass the valve 31.
• the second pump 44 is used for drainage of the peritoneal cavity of a patient.
• This second pump can also be used at the start of a step of filling a container or the peritoneal cavity of a patient subjected to a treatment by peritoneal dialysis.
• a second discharge line 10 has one end connected to the second line 2 of the main circuit, immediately downstream of the adjustable valve 36, and its other end is connected to the sewer. On this line 10 are arranged, in order from the second line 2, a first valve 33, a second valve 34, and a non-return valve 93. As described in detail below, this line of evacuation 10 is used during peritoneal dialysis treatment, outside the steps of filling the patient's peritoneal cavity.
• the first and second evacuation pipes 7, 10 are connected by a connecting pipe 11, having one end connected to the pipe 7, between the valve 29 and the second additional cooling means 531, and its other end connected to the pipe 10, between valves 33 and 34. On this connecting pipe 11 is arranged a valve 35.
• the device for preparing and dispensing a sterile liquid according to the invention further comprises a third line 12 mounted as a bypass to the first line 1, between a first point located downstream of the first pump 40 and a second point located upstream of the first exchanger 51.
• On this third pipe 12 are arranged, in order from the pump 40, second additional heating means 532 and a valve 24.
• the second additional heating means 532 are combined with the second means of additional cooling 531 to form a fourth heat exchanger 53.
• the third pipe 12 and its accessories, as well as the adjustable valve 37 disposed on the first discharge pipe 7, are part of the device's sterilization means (second pipe 2 and connector 90).
• the device shown in FIG. 1 also comprises a plurality of pressure and temperature measurement means arranged at various points in the main circuit (pipes 1 and 2), the first discharge pipe 7, and main heating means 80.
• a pressure sensor is connected to the following pipes, at the following points:
• a temperature sensor is connected to the following pipes, at the following points:
• the device according to the invention further comprises a control unit (not shown).
• This unit receives the information measured by the pressure sensors 70 to 72, by the temperature sensors 60 to 68 and the flow meters 74 and 75. From this information, from the set value for the operating parameters communicated by an operator (notably, possibly, the flow rate of the liquid), and from a command and control program stored in a memory of the control unit, this unit controls and controls the operation of the device.
• the control unit controls and validates the sterilization treatment applied on the one hand to the liquid, on the other hand to the device.
• a parameter representative of the sterilizing value of the treatment used which can be calculated , for example, from an algorithm modeling the temperature distribution inside the exchanger 51 of the main heating means 80, and from the value of at least one of the parameters likely to influence the treatment sterilization, namely the flow Q of the liquid to be sterilized in one exchanger 51, the temperature of the liquid to be sterilized (Tin) at the inlet of the exchanger 51 and the temperature of the heating liquid (THin) at the inlet of the exchanger 51.
• control unit is programmed to calculate at regular intervals the value of the parameter representative of the sterilizing value of the treatment, on the basis of the temperature distribution algorithm in the exchanger 51, and temperature and temperature information. flow measured by the corresponding sensors. Each time a new parameter value is calculated, the control unit checks that this calculated value is greater than the set value and validates the sterilization of the liquid.
• This control method which makes it possible to validate the effective sterilization of the liquid as resulting from the correct implementation of the device according to the invention can be passive. Indeed, given that the sterile state is a crucial characteristic of a medical liquid to be injected, it is possible to provide a standard operating mode of the sterilization device where the choice of the flow rate of the liquid to be sterilized is limited to a limited number of different predetermined values (for example three) and where all the other operating parameters of the device are preset according to the predetermined flow rates so that the operation of the device is simplified as much as possible. The control method described above is then used only to validate the sterilization.
• the control unit can be used to calculate, from the chosen flow rate and the setpoint of the parameter representative of the sterilizing value, the other operating parameters of the device, in particular the temperature of the heating liquid. .
• the control unit regularly adjusts the flow rate of the first pump 40 and / or the temperature of the heating liquid, so that the calculated value of the parameter is always greater than the set value.
• the parameter designated in the literature by F0 (expressed in minutes) is used as the parameter representative of the sterilizing value of the sterilization process. Recall that F0 is the sum F ⁇ of the sterilizing effects accumulated during a
• sterilization treatment (or "sterilizing value F ⁇ ") when the reference temperature T is equal to 250 ° F (121, 1 ° C) and the thermal inactivation value Z is equal to 18 ° F (10 ° C) .
• the thermal inactivation value Z is the rise in temperature which multiplies by ten the speed of destruction of a specific microorganism.
• Z 10 ° C corresponds to a theoretical microorganism slightly more resistant than the microorganism reputed to be more heat resistant than any other spore-forming microorganism, Bacillus stearothermophilus.
• This formula is not directly applicable to the control of a sterilization treatment where the liquid to be sterilized is in permanent flow and where the heating means used to raise the temperature of the liquid to be sterilized do not carry this liquid at any point of the heating enclosure at the same temperature.
• the heating means when the heating means are arranged to heat the liquid to be sterilized along a portion of the pipe where the liquid is circulated, the following formula can be used to calculate F0:
• L length of the pipe portion (heating enclosure 511) through which the liquid to be sterilized is heated by the heating means 80;
• T (y) equation of the distribution of the temperature of the liquid as a function of the distance from the inlet of the heating enclosure 511.
• the equation T (y) depends on the structure of the exchanger 51 of the main heating means 80 and on its mode of operation.
• FIG. 3 represents a first embodiment of an exchanger adapted to the device of the invention.
• This exchanger consists of two concentric pipes, the outside pipe forming a jacket 512 around the inside pipe which constitutes the heating enclosure 511 mentioned above.
• the liquid to be sterilized and the heating liquid (ethylene glycol) coming from the tank 81 are circulated, against the current, in the internal pipe (heating chamber 511) and in the external pipe (jacket 512).
• the internal diameter of the heating enclosure 511 is chosen so that, in the range of flow rates where the operating flow rates of the sterilization device (for example from 100 to 400 ml / min.), the flow of the liquid to be sterilized is always turbulent.
• T (y) Tin + (THin -Tin) x r x e -nL
• Tin temperature of the liquid to be serialized at the inlet of the heating chamber 511 (as measured by the sensor 63).
• THin temperature of the heating liquid at the inlet of the jacket 512 (as measured by the sensor 61).
• the sterilizing value F0 it is possible to calculate the sterilizing value F0 at any time, from a measurement of the temperature Tin of the liquid to be sterilized at the inlet of the exchanger 51, from a measurement of the temperature THin of the heating liquid at the inlet of the exchanger 51, of a measurement of the flow rate Q of liquid to be sterilized and of an equation modeling the distribution of the temperatures inside the exchanger 51.
• the control unit validates the sterilization treatment implemented by checking that the calculated sterilizing value F0 is always higher than a first threshold value FOminl corresponding to the sterility of the liquid.
• the main circuit of the device must be sterilized, from the exchanger 51 to the connector 90 included, that is to say beyond the connector. 90, for example up to the level of the temperature sensor 67 connected to the first sterilization pipe 7.
• the sterilization of the main circuit can be considered to be effective when all the points of the main circuit downstream of the exchanger 51 have been worn, by sterile liquid, at a minimum temperature of T2 for a minimum time of t2, which corresponds to a second sterilizing setpoint value F0min2, such as:
• T2-121 FOmin2 t2 x 10 10
• the validation of the sterilization of the main circuit can be carried out simply by the control unit by checking that for an uninterrupted period of time of a duration at least equal to t2, the temperature of the liquid measured by the temperature sensor 67 has constantly was greater than T2.
• the control unit must validate both the sterilization of the liquid and the sterilization of the main circuit. In other words, the control unit must check both that the sterilizing value of the sterilization treatment applied to the liquid is higher at FOminl and that the sterilizing value of the sterilization treatment applied to the circuit is greater than F0min2.
• the operation of the device essentially comprises the following four phases:
• the first phase corresponds to the initial sterilization of the device.
• the second phase corresponds to a state. the device is kept sterile and produces sterile water at low flow rates. This second phase occurs just after the initial sterilization of the device or between two active phases of device operation, filling of the patient's peritoneal cavity and drainage of this cavity after the liquid has stagnated there for a determined time.
• the third phase corresponds to the continuous production of the sterile solution to fill the patient's peritoneal cavity.
• the fourth phase corresponds to the drainage of the peritoneal cavity of the patient while the device is kept sterile and produces sterile water at low flow rate.
• the sterilization of the circuit is preferably carried out with water (valve 20 open, valve 21 closed).
• this first phase which comprises several stages, the valve 23 is closed and the valve 24 is open, so that the water circulated by the first pump 40 circulates in the third pipe 12.
• the first adjustable valve 36 is fully open and the second adjustable valve 37 is only partially open so that the pressure in the circuit upstream of the valve is always greater than the pressure at which the water would boil (if the water boiled, it would not be possible to validate the sterilization of the circuit, since it would not be possible to certify that the circuit has been contacted in all points by water having a minimum temperature for a minimum uninterrupted period of time).
• the pumps 43 and 44 are not in service.
• valves 26, 27, 28, 29, 30, 32, 34 are closed, and the valves 33, 35, 31 are open, so that, downstream of the first adjustable valve 36 , the water flows in a part of the second evacuation pipe 10, in the connecting pipe 11, then in the first evacuation pipe 7.
• valves 26, 27, 28, 29 are open, so that the water then also flows into the end of the second pipe 2, through the connector 90 and then into the first evacuation pipe 7, as soon as it is connected to the connector 90.
• valves 33, 35 are then closed, so that the water no longer circulates in the start of the second evacuation pipe 10.
• the duration of these three stages, as well as the flow of water in the circuit, the degree of opening of the valve 37, and the intensity of the heating provided by the heating means main 80 are either set to preprogrammed values or adjusted according to one another so that the sterilizing value of the sterilization treatment applied to the water and to the circuit is greater than the first and the second setpoint FOminl, F0min2 .
• the control unit also checks that, taking into account the actual operating conditions of the device, as measured by the various sensors, the effective sterilizing value is greater than FOmin1 and F0min2.
• the flow of water circulated by the pump 40 is adjusted to 250 ml / min.
• the pressure in the circuit upstream of the valve 37 is adjusted to seven bars
• the temperature of ethylene glycol at the inlet of the exchanger 51 is adjusted to 165 ° C. (the pressure in question here, as in the whole document, is the absolute pressure).
• the temperature of the water at the outlet of the exchanger 51 is then at least equal to 153 ° C. and the temperature upstream from the fourth exchanger 53, as measured by the sensor 67, is at least equal to 131 ° C.
• the duration of the different stages is chosen so that the sterilizing value of the sterilization treatment applied to the liquid is greater than 30 min. and the sterilizing value of the sterilization treatment applied to the circuit is greater than 30 min.
• Second phase putting the device on hold.
• the main objective of this phase is to have sterile water at a temperature of 37 ° C and at atmospheric pressure at the connector 90.
• the valve 23 is opened so that the water circulated by the pump 40 flows both in the first pipe 1 and in the third pipe 12.
• the valve 24 is closed so that the third line 12 is isolated.
• the valve 25 of the main cooling means is open and the pump 43 is put into service.
• the water is cooled in the exchanger 52, from which it leaves about 37 ° C.
• the first adjustable valve 36 is gradually closed and the second adjustable valve 37 is gradually opened so that at no time , the water does not boil, whatever its temperature, and that, when the adjustment of the valves 36, 37 is complete, the pressure upstream of the first adjustable valve 36 is of the order of seven bars and the pressure upstream of the second adjustable valve 37 is of the order of one bar (atmospheric pressure).
• the valve 30 mounted in bypass to the second adjustable valve 37 is closed.
• the valves 33, 34 are opened, so that the water also flows into the second discharge line 10.
• a fourth step the valves 26, 27, 28, 29 are closed, so that the sterile water no longer flows except in the second discharge line 10 and that the water stagnates in the portion of circuit comprising the connector 90.
• this operating mode of the device which is a standby mode, all the sterile water is sent to the sewer.
• the flow rate of the pump 40 is reduced at maximum, that is to say up to a value (100 ml / min.) where the flow of water in the heating chamber 511 remains turbulent.
• the temperature of the heating liquid of the main heating means 80 is lowered accordingly.
• the control unit checks at regular time intervals that the sterilizing value F0 of the treatment applied to water, as calculated from the measured values of the flow Q and temperatures Tin, THin at the inlet of the exchanger 51, is always within a range of values having the first setpoint value FOminl as the lower limit (for example between 30 min. And 40 min.).
• Third phase production of sterile medical liquid.
• the objective of this third phase is to produce a sterile medical liquid and to perfuse this liquid in the patient's peritoneal cavity.
• a first step consists in closing the valve 20 and in opening the valve 21 which gives access to a source of medical liquid to be sterilized so that the medical liquid replaces the water in the first line 1, in the second line 2 until the first adjustable valve 36, and in the second discharge pipe 10.
• the second step of the third phase consists in opening the valves 26, 27, 28, 29, 31 so that the sterile medical liquid replaces the water in the end of the second pipe 2, the connector 90 and the first pipe d 'evacuation 7. Then the valves 33, 34 are closed, so that the liquid is no longer routed to the sewer except through the first evacuation pipe 7.
• the third step consists in connecting the patient to be treated to the device by means of a flexible pipe (not shown), having one end connected to the catheter of the patient and another end connected to the connector 90 of the device. During the three preceding steps, the flow rate of the medical liquid controlled by the pump 40 is adjusted to a set perfusion rate suitable for the patient.
• the flow of liquid at the outlet of the connector 90 is controlled by the comparison between the pressure measured by the pressure sensor 71 and a set pressure corresponding to an admissible pressure for the patient.
• a first possibility consists in modifying the rate of the first pump 40, which may require correspondingly modifying the temperature of the heating liquid.
• another possibility consists in opening the valves 28, 29, 32, in closing the valve 31 and in controlling the second pump 44 at appropriate flow.
• the filling of the peritoneal cavity of the patient is not carried out at a constant rate as soon as the patient connects to the device and the infusion at nominal rate is preceded by a transient phase where the rate is gradually increased until the nominal flow rate is reached.
• the first evacuation pipe is used. 7 and the second pump 44 for withdrawing from the connector 90 and sending a decreasing fraction of the liquid sterilized by the device to the sewer.
• the valves 28, 29, 30, 32 are open, the valve 31 is closed, and the second pump 44 is put into service at the same rate as the main pump 40.
• the second pump 44 is controlled so that its flow gradually decreases until it becomes zero (pump 44 stopped).
• This filling phase ends either when a predetermined quantity of liquid, calculated using the information supplied by the flow meters 74 and 75, has been perfused, or when the pressure measured by the pressure sensor 71 reaches a predetermined pressure. In the latter case, the control unit calculates using the information supplied by the flow meters 74, 75 the total quantity of liquid infused.
• Fourth phase drainage of the patient's peritoneal cavity.
• This phase follows the waiting phase described above, during which the device produces sterile water at a low flow rate to maintain the sterility of the device, this sterile water being sent to the sewer by the second pipe of evacuation 10.
• the drainage of the peritoneal cavity of the patient is controlled when the liquid perfused during the previous filling phase has stagnated in the peritoneal cavity for a predetermined period.
• the valves 28, 29, 30, 32 are open and the pump 44 is put into service at a predetermined flow rate.
• the pump 44 is stopped when the amount of liquid drained is equal to the amount of liquid previously perfused, increased by an amount of liquid corresponding to the weight that the patient must lose during each phase of stagnation. According to a variant, the pump 44 is stopped when the pressure measured by the pressure sensor 71 reaches a determined low threshold value. At the end of this drainage phase, the valve 20 is closed and the valve 21 is opened so that the device again sterilizes medical liquid.
• FIG. 2 represents a second embodiment of the device according to the invention.
• This device essentially comprises main heating means 80 having a heating enclosure 511 for the liquid, and a main circuit having a first pipe 1 connected to an inlet of the heating enclosure 511 and a second pipe 2 connected to an outlet of the heating chamber 511.
• the main heating means 80 comprise a tank 81 containing a heating liquid, such as oil or ethylene glycol.
• the heating enclosure 511 which is shaped in a helix, is arranged in the tank 81 so as to be immersed in the heating liquid.
• An adjustable heating element 84 makes it possible to raise the temperature of the heating liquid.
• the heating means 80 further comprise means for homogenizing liquid constituted by a pipe 83 connecting the lower part to the upper part of the tank 81, on which a pump 42 is arranged.
• the first pipe 1 has an inlet which can be connected either to a source of water or to a source of medical liquid.
• the following members are connected to the first pipe 1, in order from the entry of the pipe 1: a flow meter 74; a first pump 40; a valve 23; first and second additional heating means 541, 551.
• the second pipe 2 connects the outlet of the heating enclosure 511 to an inlet of a sterilizable connector 90, having a first outlet for dispensing the sterile liquid.
• first additional cooling means 552 which are advantageously combined with the second additional heating means 551 to form a first heat exchanger 55
• second additional cooling means 542 which are advantageously combined with the first additional heating means 541 to form a second heat exchanger 54
• main cooling means 56 a valve 27
• first pressure regulation means 36 constituted by a valve calibrated at a first pressure threshold (five bars); and a valve 26.
• the heat exchangers 54, 55 are preferably shaped like the exchanger shown in FIG. 4, namely by the junction over part of their length of the pipe 1 and of the pipe 2.
• the two portions of pipes contiguous are shaped to form a helix with contiguous turns, and the interior and exterior of the cylinder thus formed are covered with a material which is a good conductor of heat.
• the main cooling means 56 comprise a tank 57 having an inlet connected to a source of cold water by a pipe 5 and an outlet connected to the sewer by a pipe 6 on which is disposed a valve 25.
• a drain pipe 15 provided with a valve 39 is connected to the pipe 5 to allow the emptying of the tank 57 by gravity when the supply of the pipe 5 with cold water is interrupted and the valves 25 and 39 are open.
• Line 2 comprises a portion 522 shaped as a helix, which is arranged in tank 57 so as to be immersed in cold water.
• the cooling means 56 are further provided with liquid homogenization means constituted by a recirculation line 58 connecting the lower part to the upper part of the tank 57, on which a pump 43 is arranged.
• the pump 43 rotates permanently, and the temperature of the water in line 2 downstream of the cooling means, which is measured by a temperature sensor 65, is compared to a reference temperature: when the temperature of the water in line 2 exceeds the reference temperature, the valve 25 is opened until the temperature of the water in the pipe 2 has dropped below the reference temperature.
• the sterilization device shown in FIG. 2 also includes a first evacuation pipe 7 which is connected to a second outlet of the connector 90, thus that a second discharge line 10 which is connected to the second line 2 of the main circuit.
• the first evacuation pipe 7 is used for drainage of the peritoneal cavity of a patient, when the device according to the invention is used for the treatment of a patient by peritoneal dialysis; it is also used, partially, during the sterilization of the second pipe 2 and of the connector 90.
• the following members are connected to the first discharge pipe 7, in order from the connector 90: a first valve 28; a second valve 32; a second flow meter 75; a third valve 35; and a pump 44.
• the second discharge line 10 has one end connected to the second line 2 of the main circuit, between the calibrated valve 36 and the valve 26, and its other end is connected to the sewer.
• the second evacuation pipe 10, on which are disposed a first valve 33 and a second valve 34, is used during a peritoneal dialysis treatment, outside the patient's perfusion steps.
• the first and second evacuation pipes 7, 10 are connected by a connecting pipe 11, having one end connected to the pipe 7, between the valves 28 and 32 and its other end connected to the pipe 10, between the valves 33 and 34.
• a valve 29 is arranged on this connecting pipe 11.
• the device shown in FIG. 2 further comprises means used specifically for the sterilization of the second pipe 2 of the main circuit and of the connector 90, namely a third pipe 12 mounted as a bypass to the first pipe 1, and a fourth pipe 13 mounted as a bypass to the second discharge pipe 10.
• the third pipe 12 has one end connected to the first pipe 1 between the pump 40 and the valve 23 and its other end connected to the first pipe 1 between the two heat exchangers 54, 55.
• On this third pipe 12 are arranged, in the direction of circulation of the liquid, a valve 24 and third additional heating means 532.
• the fourth pipe 13 has one end connected to the second discharge pipe 10 between the valves 33 and 34 and its other end connected to the pipe 10 downstream of the valve 34.
• third additional cooling means 531 second pressure regulation means constituted by a valve 37 calibrated at a second pressure threshold (three bars) and a valve 31.
• the third additional heating means 532 are combined with the third additional cooling means 531 to form a heat exchanger 53 shaped like the exchanger shown in Figure 4.
• the device shown in Figure 2 further comprises a plurality of measuring means pressure and temperature arranged at various points in the main circuit (pipes 1 and 2), from the a first evacuation pipe 7, means for main heating 80 and main cooling means 56.
• a pressure sensor is connected to the following pipes, at the following points:
• a temperature sensor is connected to the following pipes, at the following points: - on the first pipe 1, at the outlet of the heating enclosure 511 of the main heating means 80 (item 64);
• the device shown in Figure 2 further includes a command and control unit (not shown).
• This unit receives the information measured by the pressure sensors 70, 71, the temperature sensors 60, 62, 64, 65 and the flow meters 74 and 75. From this information, operating parameters communicated by an operator, and d calculation algorithms and control programs stored in a memory, the control unit commands and controls the different operating phases of the device. The operation of this device is not fundamentally different from the operation of the device shown in FIG. 1.
• the main cooling means 56 are out of service: the pump 43 is stopped, the valves 25 and 39 are open and the cold water supply to line 5 is interrupted so that the reservoir 57 is empty.
• the valves 24, 26, 27, 28, 29, 31 are open and the valves 23, 32, 33, 34, 35 are closed.
• the valve 33 is open and one of the valves 26, 28, 29 is closed.
• the pressure in the main circuit between the pump 40 and the valve 36 calibrated at the first pressure value is five bars
• the pressure between the valve 36 and the valve 37 calibrated at the second pressure value is three bars
• the pressure downstream of the valve 37 is one bar (atmospheric pressure).
• the temperature of the heating liquid is adjusted so that, for an adequate configuration of the heating means and for an appropriate flow rate, the temperature of the water in the pipe 12 downstream of the third exchanger 53 is 110 ° C.
• the temperature of water at the outlet of the heating enclosure 511 is 150 ° C.
• the temperature of the water downstream of the first and second exchangers 54, 55 and upstream of the third exchanger 53 is of 130 ° C
• the temperature of the water in line 13 downstream of the third exchanger 53 is 60 ° C.
• the time at which the second line 2 and the connector 90 are left in contact with sterile water at 130 ° C. is sufficient to guarantee their sterility, that is to say also that the sterilizing value FO of the sterilization treatment applied to them is greater than the second threshold value F0min2.
• valves 23, 27, 33, 34 are open and the valves 24, 26, 28, 29, 31, 32, 33, 35 are closed.
• the main cooling means 56 are in service (pump 43 in operation, valve 39 closed, valve 25 open intermittently).
• valves 23, 26, 27, 28, 32 are open and all the other valves are closed.
• the main cooling means 56 are in service (pump 43 in operation, valve 25 intermittently open).
• the pressure in the main circuit between the pump 40 and the valve 36 calibrated at the first pressure value is five bars and the pressure downstream of the valve 36 is one bar (atmospheric pressure) .
• the temperature of the heating liquid is adjusted so that, for an adequate configuration of the heating means, the temperature of the water leaving the heating enclosure 511 is 150 ° C., the temperature of the water in downstream of the first and second exchangers 54, 55 is 60 ° C, and the water temperature downstream of the main cooling means is 37 ° C.
• the sterilizing value FO of the sterilization treatment applied to water or to the medical liquid is greater than the first threshold value FOmin1.
• the invention is not limited to the exemplary embodiments which have just been described and it is susceptible of variants.

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• 1999
  • 1999-03-30 FR FR9904209A patent/FR2791576B1/fr not_active Expired - Fee Related
• 2000
  • 2000-02-24 AU AU25676/00A patent/AU768128B2/en not_active Ceased
  • 2000-02-24 WO PCT/IB2000/000196 patent/WO2000057925A1/fr not_active Application Discontinuation
  • 2000-02-24 EP EP00903926A patent/EP1083940A1/de not_active Withdrawn
  • 2000-02-24 CA CA002333786A patent/CA2333786A1/fr not_active Abandoned

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