Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
  • A61M5/00—Devices for bringing media into the body in a subcutaneous, intra-vascular or intramuscular way; Accessories therefor, e.g. filling or cleaning devices, arm-rests
  • A61M5/14—Infusion devices, e.g. infusing by gravity; Blood infusion; Accessories therefor
  • A61M5/142—Pressure infusion, e.g. using pumps
  • A61M5/14244—Pressure infusion, e.g. using pumps adapted to be carried by the patient, e.g. portable on the body
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
  • A61M5/00—Devices for bringing media into the body in a subcutaneous, intra-vascular or intramuscular way; Accessories therefor, e.g. filling or cleaning devices, arm-rests
  • A61M5/14—Infusion devices, e.g. infusing by gravity; Blood infusion; Accessories therefor
  • A61M5/168—Means for controlling media flow to the body or for metering media to the body, e.g. drip meters, counters ; Monitoring media flow to the body
  • A61M5/16877—Adjusting flow; Devices for setting a flow rate
  • A61M5/16881—Regulating valves
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
  • A61M5/00—Devices for bringing media into the body in a subcutaneous, intra-vascular or intramuscular way; Accessories therefor, e.g. filling or cleaning devices, arm-rests
  • A61M5/14—Infusion devices, e.g. infusing by gravity; Blood infusion; Accessories therefor
  • A61M5/142—Pressure infusion, e.g. using pumps
  • A61M5/14244—Pressure infusion, e.g. using pumps adapted to be carried by the patient, e.g. portable on the body
  • A61M2005/14264—Pressure infusion, e.g. using pumps adapted to be carried by the patient, e.g. portable on the body with means for compensating influence from the environment
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
  • A61M2205/00—General characteristics of the apparatus
  • A61M2205/02—General characteristics of the apparatus characterised by a particular materials
  • A61M2205/0244—Micromachined materials, e.g. made from silicon wafers, microelectromechanical systems [MEMS] or comprising nanotechnology

Definitions

• Deliyrance device for a liquid comprising a pump and a valve
• the invention relates to a device for delivering a liquid comprising a pump comprising an inlet pipe adapted to be connected to a liquid reservoir and connected to an input control member of the pump, an outlet pipe connected to an outlet control member of the pump, a pumping part comprising control means provided with a pumping membrane and a pumping chamber whose volume is variable according to the deformation of the pumping membrane.
• a siphoning effect is a major problem for users of pumps injecting liquid medicine. If the pump or liquid drug reservoir is located at a height greater than that of the injection site on the patient's body, the liquid column of the injection line creates a pressure that draws the liquid into the body of the patient if the pump is not completely sealed.
• CSII Continuous Subcutaneous Infusion of Insulin
• this case can occur if a user of such a type of pump takes a bath in the sea or a pool with this pump.
• the membrane of the hydrophilic filter that protects the ventilation system of the water inlet is blocked by the salt resulting from the drying of this seawater and in this case the pressure of the water.
• sea level air of about 100 kPa becomes trapped inside the case.
• this user climbs a plane that rises in the air quickly to the cruising altitude, in which the cabin has a predetermined pressure of about 72kPa which is below the sea level pressure value, the pressure that was trapped in the housing will cause a 28 kPa thrust of the liquid drug from the reservoir to the patient.
• a patient may have his pump at a higher level than the injection site.
• a depression will be established at the outlet of the pump by the siphon effect, by the weight of the liquid.
• the liquid drug will be driven by this pressure difference (or siphon pressure P s , ph) to the patient.
• these pressure differences can reach up to 10 kPa.
• crack valves are used in the liquid circulation zone, which are closed by default and open at pressures greater than the maximum pressure difference that can be expected (EP 0 882,466).
• the pump must overcome for each injection the barrier erected by this valve.
• This solution therefore has the disadvantage of increasing the pressure required to perform the injection. This increase in injection pressure causes damage in the amount of energy consumed and the dosing accuracy of the pump.
• larger pressure differences between the tank and the pump outlet than those normally expected can open the valve. The sizing of the valve is critical.
• a three-way anti-siphon valve may be used as the outlet control member of the pump itself.
• ASV three-way anti-siphon valve
• Such an anti-siphon valve forms an integral part of the pump and has an inlet duct 20 and an outlet duct 3 for the liquid as well as a reference port ( reference pressure P re f which is the outside pressure above the mobile membrane 18a), no liquid flow is possible from the reference port towards the outlet through such a valve.
• the liquid circulation zone between the inlet and the outlet opens or closes in the first place as a function of the pressure differences between the input port P en and the reference port P re f and between the reference port p ref and the output P SO r.
• FIG. 1 a state of the valve, characterized by the two pressure differences ⁇ P in and ⁇ P SO r, is represented by a point with the coordinates ( ⁇ P in , ⁇ P SO r) - If this point is located in the hatched area the valve is closed, if the point is located in the unhatched area the valve is open.
• the curve separating the two zones represents the transition between opening and closing, and is therefore characteristic for the valve.
• the valve opens when the pressure difference .DELTA.P is greater at S in (input pressure threshold), which is another fixed value intrinsic to the anti-siphon valve.
• FIG. 2 is a more general example of a curve representative of the principle of opening and closing of these antisiphon valves, for a representation which is no longer rectilinear as in FIG. 1.
• f ( ⁇ P sor ) S in + ⁇ P sor (S e n / S SO r), but which presents another form in accordance with the general principle of a relation f ( ⁇ P sor ).
• additional pressure differences between the P res liquid reservoir and the injection pump outlet will allow the siphon valve to close ( ASV), whether because of the arrangement of the pressures inside the pump or because of a column of liquid sucking the liquid from the outlet of the pump.
• the anti-siphon valve will therefore be well closed, if Ssor ⁇ 28 kPa. If for any reason the pressure difference ⁇ Psor will be even greater than 28 kPa the anti-siphon valve will remain closed and thus will fulfill its safety function.
• micropumps such as those used in EP183957, have advantages for the injection of liquid drugs, among which a high accuracy and a small volume of pumping. With micromachining technology, micropumps can also be produced which have a sufficiently high compression ratio to be self-priming, despite their small pumping volume. This is achieved by reducing all volumes in the pump in relation to the pumping volume.
• the valves are made from hard materials (for example silicon), since it is not possible to integrate soft materials into micro-machining processes, especially for the moving part. and / or the seat of the valve.
• this type of pump is extremely sensitive to dust and particles that can be housed between the valve hard surfaces in contact with hard materials, thus preventing any possibility of sealing.
• Leaky valves allow dangerous leaks if there is a pressure difference between the liquid drug reservoir and the injection site.
• the present invention aims to provide a device for overcoming the disadvantages of the prior art and in particular offering the possibility of combining the advantages of self-priming micropumps and anti-siphon valves less sensitive to particles.
• the device for delivering a liquid presented above is characterized in that it further comprises an anti-siphon valve external to the pump, having an inlet duct connected to the pipe of outlet of the pump and an outlet duct between which is disposed a seat and movable member adapted to cooperate together and which delimit, between the inlet duct and the outlet duct of the valve, a sealed liquid circulation zone, said movable member being adapted to pass from an open position allowing the flow of liquid in said circulation zone, to a closed position, in which the movable member comes into contact with the seat of the valve and prevents any circulation in said circulation zone, said movable member being subjected to the pressure of a reference chamber which is not in fluid communication with the outlet duct.
• an anti-siphon valve external to the pump, having an inlet duct connected to the pipe of outlet of the pump and an outlet duct between which is disposed a seat and movable member adapted to cooperate together and which delimit, between the inlet duct and the outlet duct of the valve,
• an anti-siphon valve external to the pump can advantageously be obtained by different techniques of micromachining techniques, so to form for example macroscopic anti-siphon valves less susceptible to particles.
• the seat and / or the movable member of said anti-siphon valve is made of a flexible material, for example elastomer, in particular silicone or natural rubber or synthetic rubber.
• such an outer valve will have a larger size than the size of a micro-machined valve, and therefore also a larger dead volume.
• the micropump will have to compress the gas throughout the volume up to the opening threshold S en of the outer valve for this gas to enter this valve and advance the liquid.
• the dead volume and the opening threshold (or inlet pressure threshold) S en of this external valve will therefore influence the self-priming properties of the micropump and therefore of the complete system.
• the passage between the closed position and the open position of the movable member of the anti-siphon valve is controlled at least by the pressure P re f prevailing in the reference chamber.
• ⁇ P in Pen - Pre f
• ⁇ P sor Pref - Psor-
• the outer valve is open by default, and therefore the pressure threshold S sor predetermined output is positive and the inlet pressure in predetermined threshold S is negative.
• This preferred embodiment is illustrated in FIGS. 5 and 6.
• the movable member is in the open position when said valve is in the equilibrium position in which the pressures in the inlet duct (P in ), in the output duct (P SO r) and in the reference chamber (P re f) are equal to each other.
• the movable member moves into the closed position, from said equilibrium position of the anti-siphon valve, if the pressure in the outlet duct (P SO r) is lowered by at least the value of a threshold predetermined pressure output (S SO r), the pressures in the inlet duct (P en ) and in the reference chamber (P re f) remaining constant. Also, the movable member moves into the closed position, from said equilibrium position of the anti-siphon valve, if the pressure in the reference chamber (P ref ) is increased by at least the absolute value of a threshold of predetermined inlet pressure (S en ), the pressures in the outlet duct (P SO r) and in the reference chamber (P ref ) remaining constant.
• the self-priming capacity of the micropump is also not affected by the external anti-siphon valve since it is not necessary to compress the gas at the pump outlet to exceed the pressure threshold at the inlet S in and bring the gas into the anti-siphon valve.
• the pump is a micropump, that is to say a micromechanical pump manufactured by micromachining techniques.
• said predetermined closing pressure threshold (S SO r) is less than 1 opposite of the siphon pressure (-P S i P h) prevailing in the valve, if said injection line is disposed vertically with the distal end (the one that is close to the patient) at the bottom.
• said reference pressure (P ref ) is substantially equal to the pressure prevailing in the inlet pipe of the pump, when the pump is at rest (inactive) or in equilibrium state.
• said valve has a valve body in which said inlet duct, said circulation zone and the outlet duct are formed;
• said movable member belongs to a flexible film which is sealingly attached to the surface of the valve body, and extends along said circulation zone.
• said flexible film is made of an elastic material or combinations (such as superimposed layers) of polymers such as polyvinyl chloride, polyethylene, polycarbonate, polyamide, or a polyolefin, and in particular an elastomeric polymer.
• polymers such as polyvinyl chloride, polyethylene, polycarbonate, polyamide, or a polyolefin, and in particular an elastomeric polymer.
• silicone, polybutadiene, Viton (registered trademark) synthetic rubber, ethylene propylene rubber, or natural rubber such as silicone, polybutadiene, Viton (registered trademark) synthetic rubber, ethylene propylene rubber, or natural rubber;
• said reference chamber is in communication with the inlet pipe of the pump
• the device further comprises a liquid reservoir connected to said inlet pipe of the pump;
• the reference chamber is subjected to the same pressure (P ref) that the pressure (P rs) prevailing in the liquid reservoir;
• said liquid reservoir has a variable volume
• said liquid reservoir comprises a fixed reservoir body and a movable reservoir wall delimiting the cavity of said liquid reservoir; in this case, preferably, said movable tank wall is sealingly attached to the outer surface of the fixed tank body, and / or said movable tank wall is formed of a flexible film, preferably made of a polymer material or combinations (such as superimposed layers) of polymeric materials such as polyvinyl chloride, polyethylene, polycarbonate, polyamide, or a polyolefin, or in particular an elastomeric polymer such as silicone, polybutadiene, Viton (registered trademark) synthetic rubber, ethylene propylene rubber, or natural rubber;
• the pressure (P re ) prevailing in said liquid reservoir is substantially equal to the pressure prevailing outside the liquid reservoir;
• said fixed valve body and said fixed tank body are formed in one piece forming a fixed body, in particular said valve and said liquid reservoir are delimited by the same surface of said fixed body forming the valve body and tank body;
• the flexible film of the movable member and the flexible film of said movable tank wall are made from the same flexible film;
• said single flexible film comprises a first flexible layer and a second flexible layer located on the face of the film facing the reservoir and towards the seat of the anti-siphon valve, in particular said single flexible film is fixed against said surface of the body a single fixed sealably to form said circulation zone of said antisiphon valve and the cavity of said liquid reservoir;
• this waterproof fastening is for example carried out by ultrasonic welding, by thermal welding, by laser welding, by gluing, by a precision fitting technique under pressure, or by a retaining technique such as using a clip, or by hot-pressing;
• said liquid reservoir further comprises a cap mounted on said fixed tank body, said mobile tank wall being housed between said cap and said fixed tank body, in particular said reference chamber is connected to the space delimited between the hood and the movable tank wall, and / or said hood is mounted on said fixed body forming said fixed valve body and said fixed tank body, said hood and said fixed body delimiting a space which encloses said liquid reservoir and said chamber reference ;
• the pump is a pump of the volumetric type; said pump is self-priming in the absence of the antisiphon valve, that is to say that said pump has a compression ratio which is higher than the ratio of the absolute opening pressures of the input control members and the output (the compression ratio being defined as the ratio of the pumping volume to the sum of the pumping volume and the internal dead volume between the two control members);
• the pump has a small pumping volume smaller than 10 ⁇ l, preferably smaller than 1 ⁇ l, preferably smaller than 500 ⁇ l, in particular the pump is manufactured by micro-machining techniques.
• FIG. 3 is a diagrammatic sectional view of a device according to a first embodiment of the invention.
• FIG. 4 is a schematic sectional view of a device according to a second embodiment of the invention.
• FIGS. 5 and 6 are block diagrams in opening and closing of an anti-siphon valve according to a particular preferred embodiment where the outer valve is open by default.
• the device according to the invention may comprise, in accordance with the first and second embodiments described below, a pump 1 of micromechanical pump type or self-priming micropump such as that shown in EP739451, essentially made of silicon and glass.
• this micropump 1 is schematized according to the shape of a box, but among its components, it comprises:
• An outlet pipe 2 connected to the output control member of the pump 1 located upstream of the outlet pipe 2; and - A pumping part (not shown) comprising control means provided with a pumping membrane and a pumping chamber whose volume is variable according to the deformation of the pumping membrane.
• a pump 1 is chosen whose compression ratio is sufficiently high to exceed the opening pressures of the internal valves acting as input and output control members for a compressible fluid such as air.
• the inlet pipe 8 is adapted to be connected to a liquid reservoir 6 which, in the embodiment shown is an integral part of the device, but which could be in a separable form.
• the device further comprises an external anti-siphon valve 4 separate from the pump 1.
• the inlet conduit 3 of the valve 4 is connected to the outlet pipe 2 of the pump 1.
• a valve 4 is chosen, the movable portion 11 and the seat 11a located opposite each other, or at least one of them, made of a flexible material. In this way, the anti-siphon valve 4 remains sealed in its closed position despite the presence of dust and particles.
• flexible material is meant a material which is not rigid, the nature and / or thickness of which makes the mobile part 11 elastic and / or soft to deform and absorb surface state variations due to the presence of dust and particles, of a size of the order of a fraction of a micrometer to a few microns.
• this flexible material is an elastomeric polymer such as silicone, polybutadiene, Viton-type synthetic rubber, ethylene-propylene rubber, or natural rubber.
• the mobile part 11 is a flexible polymer film such as polyvinyl chloride, polyethylene, polycarbonate, polyamide, or polyolefin, with a thickness of between 5 microns and 200 microns.
• valve 4 is made in a housing 10, for example rigid plastic, in which were made: the inlet duct 3 of the valve 4 connected to the outlet pipe 2 of the pump 1,
• the outlet duct 7 of the valve 4 mounted on the upstream end of the injection line (not shown), the downstream end of which is connected to the patient, for example at the level of a catheter, and
• the film constituting the movable member 11 is sealingly attached to the surface of the valve body 10, around the seat 11a of the valve 4.
• the movable member 11 delimit a sealed liquid circulation zone located downstream of the pump 1 and upstream of the patient (no represent).
• the face of the movable portion 11 facing away from the seat 11a is in contact with a reference chamber 5 whose pressure P ref will influence the position (open or closed) of the valve 4, depending on the value of the pressure P SO r prevailing in the outlet duct 7 of the valve 4.
• the reservoir 6 has been formed in a tank body 13 delimiting a cavity that can be filled with liquid medicine, this cavity being closed by a tank wall 14.
• the tank wall 14 is mobile and formed of a flexible polymer film, sealingly attached to the surface of the tank body 13.
• the reservoir 6 is intended to be filled with liquid, without the presence of gas, in order to avoid any risk of gas entering the pump 1.
• the mobile tank wall 14 is formed of a film that can be deformed (flexible film) without being elastic or extensible.
• a polymer such as polyvinyl chloride, polyethylene, polycarbonate, polyamide, or polyolefin, with a thickness of between 5 micrometers and 200 microns.
• the housing 10 of the valve 4 and the tank body 13 form the two parts of the same part forming a fixed body 10/13 for the device, and c is a single film 11/14 which constitutes the mobile tank wall 14 and the movable member 11 of the valve 4.
• this single film 11/14 one can choose a flexible film made of material such as those presented above. It is also possible to provide a film 11/14 formed of a superposition of at least two layers:
• first layer is flexible and can be made of material such as those presented above so as not to be able to extend
• the second layer is flexible, is located on the face of the film 11/14 facing the reservoir 6 and the seat 11a of the valve 4, and is for example made of an elastomeric polymer such as silicone, polybutadiene, Viton (registered trademark) synthetic rubber, ethylene-propylene rubber, or natural rubber.
• an elastomeric polymer such as silicone, polybutadiene, Viton (registered trademark) synthetic rubber, ethylene-propylene rubber, or natural rubber.
• a cover 15 overcomes the fixed body 10/13 extending above the reservoir 6 and the valve 4, the pump 1 being located on another face of the fixed body 10/13.
• the cover 15 is not sealingly mounted on the fixed body 10/13 but it must prevent the penetration of any liquid into the device, in particular inside the cavity 16 of the cover 15. For this purpose, there is a ventilation (not shown) between the outside of the cover 15 and the cavity 16 of the cover 15, with a hydrophobic filter.
• the (gas) pressure P re f of the reference chamber 5 is therefore the same as the liquid pressure (P res ) prevailing in the reservoir 6 of liquid medicine.
• FIGS. 5 and 6 A particular preferred embodiment where the outer valve is open by default is illustrated in its operating mode in FIGS. 5 and 6 (the material structure can be that of the first embodiment of Figure 3 or the second embodiment of Figure 4).
• the valve 4 then has a pressure threshold output S SO r which is positive, that is to say it is open if the pressure P sor prevailing in the outlet pipe 7 of the valve 4 is equal to or greater at the pressure P ref prevailing in the reference chamber 5, from which the pressure threshold at the output S sor of the valve 4 (P SO r Pref Pref - S SO r) is removed, in the case where the pressure P in d entry is in equilibrium with the pressure P ref by reference.
• a pressure threshold output S SO r which is positive, that is to say it is open if the pressure P sor prevailing in the outlet pipe 7 of the valve 4 is equal to or greater at the pressure P ref prevailing in the reference chamber 5, from which the pressure threshold at the output S sor of the valve 4 (P SO r Pref Pref - S SO r) is removed, in the case where the pressure P in d entry is in equilibrium with the pressure P ref by reference.
• the valve 4 has an S input pressure threshold in a negative value: when the pressure P output sor is in equilibrium with the pressure P reference ref then the valve is opened if Dp ⁇ S en and the valve is closed if
• the pressure enclosed in the cavity 16 of the cover 15 is of the order of 100 kPa or more than 100 kPa.
• the pressure in the cabin of the plane, and therefore the output 7 of the anti-siphon valve 4 will be about 72 kPa. There will therefore be a pressure difference .DELTA.P SO r of 28 kPa between the reference chamber 5 and the outlet duct 7 of the anti-siphon valve 4.
• valve 4 closes and also plays its role anti-siphon when the pressure (P res ) of the reservoir 6 is higher than that of the injection site at the patient's body, this which prevents any leakage of liquid to the patient, not controlled by the pump 1.
• valve 4 is open by default so that it does not contribute to the dead volume of gas to be compressed from the liquid delivery device according to the present invention. So it does not affect the self-priming performance of pump 1.
• the same pressure of 100 kPa will be enclosed under the hood 15 and will act on the liquid in the tank 6 and thus also on the reference chamber 5 of the anti-siphon valve 4. If the valves 1 of the micropump are not perfectly sealed the pressure of 100 kPa will then play on the outlet pressure P sor of the valve 4 and the pressure P at the inlet of the valve 4. Then, when the user arrives on a plane at cruising altitude, the pressure in the cabin of the aircraft is 72 kPa. This scenario results in:
• the outer valve 4 has three ports (inlet duct 3, outlet 7 and reference chamber 5 which is located outside the liquid circuit). This valve 4 serves as a security between the pump 1 and the patient, because it remains in principle open and closes only in case of potential problem (if its fluidic outlet path is in depression with respect to the external pressure device ).

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• Health & Medical Sciences (AREA)
• Animal Behavior & Ethology (AREA)
• Life Sciences & Earth Sciences (AREA)
• Anesthesiology (AREA)
• Biomedical Technology (AREA)
• General Health & Medical Sciences (AREA)
• Hematology (AREA)
• Engineering & Computer Science (AREA)
• Vascular Medicine (AREA)
• Heart & Thoracic Surgery (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• Infusion, Injection, And Reservoir Apparatuses (AREA)
• Reciprocating Pumps (AREA)
• Details Of Reciprocating Pumps (AREA)

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ID=37909451

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• 2006
  • 2006-09-04 FR FR0653560A patent/FR2905429A1/fr active Pending
• 2007
  • 2007-09-03 WO PCT/FR2007/051863 patent/WO2008029051A2/fr active Application Filing
  • 2007-09-03 EP EP07823760A patent/EP2059283A2/de not_active Withdrawn
  • 2007-09-03 US US12/439,855 patent/US8167581B2/en not_active Expired - Fee Related
  • 2007-09-03 CN CNA2007800328300A patent/CN101511408A/zh active Pending
  • 2007-09-03 JP JP2009526155A patent/JP5665072B2/ja not_active Expired - Fee Related

Non-Patent Citations (1)

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