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
  • A61M5/145—Pressure infusion, e.g. using pumps using pressurised reservoirs, e.g. pressurised by means of pistons
  • A61M5/148—Pressure infusion, e.g. using pumps using pressurised reservoirs, e.g. pressurised by means of pistons flexible, e.g. independent bags

Definitions

• the present invention has its origin in an autonomous perfusion device according to the preamble of claim 1.
• infusion is an intervention technique that allows the slow and continuous introduction of a liquid, such as a drug substance or blood, into an organism.
• a liquid such as a drug substance or blood
• This operation is commonly practiced in human medicine as in veterinary medicine. It is intended to compensate for the loss of biological fluids suffered by an organism as a result, for example, of a surgical intervention, a road accident or any circumstance which has resulted in serious bodily harm. It is also common for the organism receiving the infusion to be in shock.
• the infusion consists of the flow of an appropriate liquid, contained in a flexible bag, from this pocket to the receiving organism, via a defined circuit, also called an infusion line.
• This flow must be done with a constant flow, adapted to the needs of the organism which receives it.
• the bag of liquid is maintained at a certain height above the organism to be perfused, so as to ensure a gravity flow of the liquid.
• This method is fairly easily applied in a hospital or similar environment, where the bag can be suspended at a constant height from a bracket and accompany the patient in his possible movements. Outside, for example at the scene of a road accident or a natural disaster, the maintenance of the pocket mobilizes a member of the intervention services, who is therefore no longer available for proper care missions say. In addition, the constancy of the flow is far from being guaranteed under such conditions. Furthermore, particularly with large bags, this method does not always guarantee a truly constant flow rate during the infusion, since the pressure of the liquid decreases as the bag is emptied. Finally, there is a significant risk that the patient, by an uncontrolled gesture, tears off the infusion line which connects it to the hanging bag.
• an autonomous perfusion device which comprises means for putting a perfusion bag under pressure between two parallel compression plates.
• the compression plates are essentially horizontal.
• the upper plate remains fixed and the lower plate, carrying the bag, can move upwards under the action of an elastic mechanism.
• lift the upper plate which in fact constitutes a hinged cover, in order to have access to the lower plate; closing this cover causes the elastic mechanism to be armed.
• This known device has several drawbacks. Its loading and arming mode requiring the opening of the upper cover to clear the loading opening prevents the stacking of several devices in battery in order to simultaneously perform several infusions.
• closing the cover requires the application of a significant effort, which on the one hand is required of the intervention personnel and which on the other hand can harm, by reaction, the reliability of the locking and the rigidity. of the cover. This can result in an irregularity in the pressure in the bag and therefore also in the flow rate of the infusion fluid. It should also be emphasized that this effort is higher the larger the pocket. For larger pockets, for example with a capacity of 3000 ml, the effort required may exceed the physical possibilities of the personnel. intervention; improvised mechanical means must therefore be used, which often cause loss of time.
• the invention seeks precisely to remedy these drawbacks, by proposing an autonomous perfusion device which ensures a constant flow rate of the perfusion liquid throughout its duration, which guarantees a substantially complete emptying of the infusion bags and finally which can be installed in a battery, in particular to simultaneously infuse several patients or to simultaneously inject several liquids into the same patient.
• the autonomous perfusion device will here also be considered in its normal rest position.
• an autonomous perfusion device which comprises means for pressurizing an infusion bag between a fixed plate and a movable plate driven by an elastic mechanism, is characterized in that the lower plate is fixed in the direction vertical, in that the upper plate is movable in the vertical direction under the action of said elastic mechanism, in that there is provided at least one opening in at least one side wall of the device for the introduction of an infusion bag between said two plates, in that said elastic mechanism is provided with independent control and locking means of said plates, and in that means are provided for unlocking said elastic mechanism after loading of said infusion bag.
• the lower plate is movable in its plane in the manner of a drawer, between an interior position, used for the infusion and the rest, and an exterior position, used for loading the bag into the device.
• the device comprises means for unlocking said elastic mechanism actuated by said lower plate during its return stroke to its internal position.
• the elastic mechanism comprises two sets of crossed levers, parallel two by two, in which the levers of the same set are joined by springs and the two sets of levers are assembled by transverse axes.
• the elastic mechanism thus constitutes a pantograph, controlling the vertical displacement of the upper plate under the effect of the traction of the springs, which causes a variation in the opening angle of the pantograph.
• the bandage of the springs is obtained by closing the cover and transmitting the closing force to the lower plate via the infusion bag.
• the bandage of the springs is produced by means of control independent of the compression plates.
• the means for controlling said elastic mechanism comprise its own kinematic chain, connecting a point of application of the arming force to the member for bandaging the springs and for varying the angle of opening of the pantograph.
• the arming force can be applied by a mechanical member such as a crank or a motor
• the bandage member of the springs can be a transmission by screw wheel and worm.
• suitable control members in particular mechanical, but also pneumatic or hydraulic, are well known in the art and do not require a detailed description here.
• Fig. 1 shows a front view of the device of the invention, from the side of the loading opening;
• Fig. 2 is a side view of the device of FIG. 1, with the elastic mechanism in the deployed position, the upper plate in the lower position and the lower plate in the internal position;
• Fig. 3 is a view similar to FIG. 2, but with the elastic mechanism folded, the upper plate in the high position and the lower plate in the external position, ready to receive an infusion bag.
• Figures 1 to 3 schematically show the active part of the device of the invention.
• this device can be housed in a protective or decorative case, generally parallelepipedal; to simplify the drawing, only the frame represented by the bearing edges has been shown here.
• the possible housing essentially consists of a horizontal bottom panel 1, an upper panel 2, side panels 3, 4 and possibly front panels 5 and rear 6.
• FIG 1 there is shown a front view of the device of the invention; when present, a front panel 5 has at least one opening 7, which allows in particular the loading of the bag, the outlet of the loading drawer which will be described later, and the passage of the infusion line.
• the position of the possible opening 7 is symbolized in phantom in Figure 1 and better visible in Figures 2 and 3.
• the lower plate 8 which carries an infusion bag 9; this lower plate 8 can be provided with lateral flanges 10, 11 which in particular facilitate the correct positioning of the infusion bag.
• the lower plate 8 rests on a support 12 fixed to the bottom panel 1, on which it can slide horizontally, by slides or the like 13. The sliding movement takes place between an internal or retracted position (Fig. 2), which is the work and rest position, and an outside or exit position (Fig. 3), which is the loading position.
• an upper plate 14 which can move in a vertical direction, parallel to itself, under the action of an elastic mechanism 15, known per se in the art. This mechanism and its action are better visible in Figures 2 and 3.
• the upper plate 14 is attached to the elastic mechanism 15 by means known per se and not shown here.
• the elastic mechanism 15 is composed of two sets of crossed levers 16, 17 articulated one on the other in their middle and together defining a vertical plane.
• the lever 16 of each assembly is articulated to the upper frame of the device; similarly, the lever 17 of each assembly can be articulated by its rear end to the upper plate 14.
• the two levers 16 are assembled to each other by a transverse axis 18, which rolls by example in slides provided on the upper plate 14; similarly, the other ends of the two levers 17 are assembled to one another by a transverse axis 19, which rolls under the upper frame.
• tension springs 20, 21 are tensioned between the upper ends, respectively between the lower ends, of the crossed levers 16, 17 of each assembly.
• Control means such as a crank actuating a screw wheel and a worm screw, make it possible to vary the opening angle ⁇ of the crossed levers of each assembly, and from this makes the tension in the springs 20, 21 of the two assemblies and the vertical position of the upper plate 14.
• the point of application of the arming force to these control means is preferably located in the front face 5 of the device , so as to facilitate access and limit the lateral dimensions of the device.
• each set of crossed levers 16, 17 is in fact constituted by a double set of crossed levers, arranged on either side of the respective articulation bearings of the levers on the upper panel 2 and possibly to the upper plate 14. This arrangement makes it possible to avoid the introduction of parasitic bending moments into the levers when controlling the movement of the elastic mechanism 15 and of the upper plate 14.
• Figure 3 also shows an example of a locking and unlocking system of the elastic mechanism 15.
• the bottom plate 8 is shown here in the loading position. It carries a rod 24 which comes out at the rear of the lower plate 8.
• On the rear panel 6 is arranged an elastic strip 25 which, when deformed, can actuate the hook 22 against the force of the spring 23.
• This rod 24 can for example be sliding through the bottom plate 8.
• the device comprises means for monitoring the degree of emptying of the bag during the infusion.
• These means can consist for example in a graduated window for monitoring the variation of the distance h, or a member for monitoring the angular position of the elastic mechanism 15.
• a window is advantageously located in the front panel 5 of the housing.
• the elastic mechanism 15 and the springs 20, 21 are advantageously made of a material resistant to corrosion, for example stainless steel.
• the device can thus be used without problem in humid or polluted atmospheres.
• the operating mode of the device of the invention is as follows:
• the elastic mechanism 15 is brought to the high position, by an appropriate control means. The effect of this movement is to release the lower plate 8, to close the angle ⁇ formed by the crossed levers 16, 17 and to tension the springs 20, 21.
• the elastic mechanism 15 is locked in the high position by the hook 22.
• the lower plate 8 On then moves the lower plate 8 to the loading position (Fig. 3) and an infusion bag 9 is placed there.
• the lower plate 8 is pushed back into the working position.
• the elastic mechanism 15 is unlocked, which applies the upper plate 14 to the pocket 9 under the effect of the tensile force exerted by the springs 20, 21.
• L angle ⁇ of the crossed levers 16, 17 opens.
• the upper plate 14 thus exerts pressure on the perfusion bag 9, which causes the expulsion of the perfusion liquid out of the bag towards the perfusion line, not shown here.
• the perfusion line is equipped with means for adjusting the flow rate of liquid, as well as with a device for measuring this flow rate. It is thus possible to adapt the infusion rate to each particular case and to monitor the constancy of this rate.
• the constancy of the infusion rate is conditioned by the constancy of the pressure generated within the liquid contained in the bag.
• This pressure is itself determined by the ratio between the pressure force F P exerted by the plates and the contact surface S between these plates and the infusion bag.
• the restoring force F R is in turn a linear function of the stiffness of the spring and its elongation; it decreases linearly as a function of the decrease in the elongation of the spring and consequently also as a function of the decrease in the distance h, therefore as a function of the volume perfused.
• the pressure force depends linearly on the variation of the distance h, by means of a proportionality factor which in turn depends on the stiffness of the springs and the size of the pantograph.
• the springs have a stiffness which, combined with an appropriate dimensioning of the pantograph, leads to an increase in the pressure force F P as a function of the decrease in the distance h, at least substantially equal to the increase in the contact surface S also as a function of the decrease in this distance h.
• the size of the device of the invention is adapted to the size of the pockets it receives;
• the corresponding springs in each case have a stiffness, that is to say a diameter of the wire and a number and a diameter of turns, determined so as to ensure the pressure force required as a function of the size of the pocket.

Landscapes

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

Applications Claiming Priority (3)

Publications (1)

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• 2000
  • 2000-09-21 BE BE2000/0600A patent/BE1013694A3/fr not_active IP Right Cessation
• 2001
  • 2001-09-20 IL IL15500401A patent/IL155004A0/xx unknown
  • 2001-09-20 EP EP01969089A patent/EP1333873A1/de not_active Withdrawn
  • 2001-09-20 US US10/380,762 patent/US20040026448A1/en not_active Abandoned
  • 2001-09-20 AU AU2001289437A patent/AU2001289437B2/en not_active Expired - Fee Related
  • 2001-09-20 JP JP2002528327A patent/JP2004508156A/ja active Pending
  • 2001-09-20 CA CA002424045A patent/CA2424045A1/fr not_active Abandoned
  • 2001-09-20 AU AU8943701A patent/AU8943701A/xx active Pending
  • 2001-09-20 WO PCT/BE2001/000161 patent/WO2002024258A1/fr not_active Application Discontinuation

Non-Patent Citations (1)

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