This application claims priority of German Patent Application Serial No. 10 2016 212 579.6 filed on Jul. 11, 2016, pursuant to 35 U.S.C. (a)-(d), the content of which is incorporated herein by reference in its entirety as if fully set forth herein.
The invention relates to a mobile infusion pump for the constant delivery of a fluid medium. The invention further relates to a balloon body for an infusion pump of this type and to a tube body as a semi-finished product to be used as a component of a balloon body of this type.
Mobile infusion pumps are used in ambulant medical treatment, in particular in the fields of parenteral nutrition, chemotherapy and pain management. Conventional infusion pumps are equipped with a balloon body for receiving the fluid medium. The balloon body is filled with the fluid medium by means of a filling unit, causing the balloon body to expand. The expansion of the balloon body generates restoring forces in said balloon body, which allow the fluid medium to be delivered to a patient under pressure. Delivery is carried out using a delivery unit, which forms a fluid connection between the infusion pump and a patient. Infusion pumps of this type are for instance disclosed in the specifications U.S. Pat. No. 8,398,595 B2, U.S. Pat. No. 7,341,572 and U.S. Pat. No. 8,439,862.
Therefore, the present invention is based on the object of providing an infusion pump having a precise dosage behavior during the delivery of the fluid medium. In particular, a variation of the total time of the delivery process shall amount to no more than 10% of a desired delivery time.
This object is achieved according to the invention by a mobile infusion pump for the constant delivery of a fluid medium, the mobile infusion pump comprising a balloon body for receiving the medium; a filling unit, which is in fluid connection with an internal volume of the balloon body, for filling the medium into the balloon body; and a delivery unit, which is in fluid connection with an internal volume of the balloon body, for delivering the medium from the balloon body, wherein the delivery unit is provided with a throttling unit for defining a delivery flow rate of the medium; and a part of the balloon body is a tube body with a cross-sectional profile comprising a plurality of continuous longitudinal ribs.
The mobile infusion pump according to the invention comprises a balloon body for receiving the medium, a filling unit and a delivery unit. The filling unit and delivery unit are in a fluid connection with an internal volume of the balloon body to fill the fluid medium into the balloon body and deliver the fluid medium from the balloon body to a patient. In order to define a delivery flow rate of the fluid medium, the delivery unit is further provided with a throttling or fluid restricting unit. In order to optimize the expansion behavior of the balloon body, and therefore the dosage behavior of the infusion pump, it is intended for a part of the balloon body to be configured as a tube body having a cross-sectional profile with a plurality of continuous longitudinal ribs. The longitudinal ribs increase the stability of the tube body. The expansion behavior can therefore be controlled in a targeted manner as only individual segments disposed between the longitudinal ribs are able to expand. The controlled expansion behavior of the balloon body ensures a constant delivery pressure, which allows the dosage behavior and the time of the delivery process to be defined more precisely. An unwanted varying expansion of the balloon body, which would result in a varying delivery pressure, is thus avoided. Correspondingly, there is no unwanted variation of the delivery time.
The increased stability of the tube body further has the advantage of an easier manipulation and arrangement of the balloon body in the infusion pump.
Configuring at least one of the longitudinal ribs as an internal longitudinal rib forming part of an internal profile of the tube body allows the contact of the balloon body with a support body of the infusion pump to be controlled in a targeted manner. This prevents the balloon body from adhering to the support body, which may occur when the infusion pump is stored for a longer period of time.
When at least two internal longitudinal ribs are provided, this ensures an improved distribution of the support forces of the internal longitudinal ribs along an internal profile of the tube body. Furthermore, the contact surface of the tube body with the support body is reduced even more. During delivery, a part of the fluid medium may remain in the compartments between the longitudinal ribs, which may prevent a complete emptying of the balloon body.
The embodiment in which an external profile of the tube body is produced by at least one longitudinal rib configured as an external longitudinal rib forming part of an external profile of the tube body has the advantage that the stability of the tube body is increased without preventing a complete emptying of the balloon body during the delivery of the fluid medium.
Providing a plurality of external longitudinal ribs, in particular at least two, in particular at least four external longitudinal ribs, improves the distribution of the support forces along an outer circumference of the tube body.
According to a preferred embodiment, an infusion pump is provided that combines at least one internal longitudinal rib forming part of an internal profile of the tube body and at least one external longitudinal rib forming part of an external profile of the tube body. The internal and external longitudinal ribs are arranged on the same level when seen in the circumferential direction so as to increase the stability of the respective longitudinal ribs. The support forces of the longitudinal ribs are therefore increased locally.
According to another preferred embodiment, an infusion pump is provided that combines at least one internal longitudinal rib forming part of an internal profile of the tube body and at least one external longitudinal rib forming part of an external profile of the tube body, too, with the at least one internal longitudinal rib and the at least one external longitudinal rib being arranged such as to be staggered relative to each other when seen in the circumferential direction of the tube body. Said staggered arrangement of the internal and external longitudinal ribs when seen in the circumferential direction ensures an optimal distribution of the support forces.
The invention further relates to a balloon body for an infusion pump as outlined above. Another subject matter of the invention is a tube body as a semi-finished product to be used as a component of a balloon body of this type.
An exemplary embodiment of the invention will hereinafter be explained in more detail with reference to the drawing.
In order to protect the balloon body 2 from external influences, the balloon body 2 is surrounded by a solid external housing 8. The external housing 8 is transparent, thus allowing the fill level of the balloon body 2 to be monitored at any time.
The balloon body 2 comprises a tube body 10, a closed end portion 12 and a collar 14 arranged opposite the end portion 12. The balloon body 2 encloses a cylindrical support body 16 the longitudinal axis 17 of which coincides with the longitudinal axis of the tube body 10. The collar 14 of the balloon body 2 surrounds a tapered neck portion 18 of the support body 16. In other words, the support body 16 is disposed entirely inside the internal volume of the balloon body 2. The collar 14 ensures that the internal volume of the balloon body 2 is sealed with respect to the remaining housing and the balloon body 2 is held on the support body 16. The support body 16 is connected to the external housing 8. A tube connector 20 is arranged on the external housing as an extension of the support body 16. The support body 16 is configured as a hollow body that is in fluid connection with the tube connector 20. A fluid connection between the hollow body of the support body 16 and the internal volume of the balloon body 2 is provided by radial holes 22 through the cylindrical shell of the support body 16.
In the exemplary embodiment shown, the tube connector is provided with a tube 24 forming part of the fluid connection between the internal volume of the balloon body 2 and the filling unit 4 or the delivery unit 6, respectively. A coupling 26 is arranged at the end of the tube 24 opposite the tube connector 20. By means of the coupling 26, a fluid connection can be formed selectively between the tube 24 and the filling unit 4 for filling in the fluid medium or between the tube 24 and the delivery unit 6 for delivering the fluid medium. The tube 24 is provided with a valve 28 for shutting off the fluid connection. The valve 28 may in particular be configured as a tube clamp. In other words, the fluid connection between the internal volume of the balloon body 2 and the filling unit 4 or delivery unit 6, respectively, comprises the coupling 26, the tube 24 comprising the valve 28, the tube connector 20 and the support body 16 configured as a hollow body. As an alternative to the embodiment shown here comprising a single tube 24 and a coupling 26, it is possible as well to provide separate fluid connections for the filling unit 4 and the delivery unit 6.
The filling unit 4 is not shown in more detail in
The delivery unit 6 arranged downstream of the coupling 26 comprises a throttling unit 30 for defining a delivery flow rate of the fluid medium. The rest of the delivery unit 6 is not shown explicitly in
The balloon body 2 is made of an elastic material. In the empty state, the internal volume of the balloon body 2 is minimal. The internal volume is however at least equal to the volume of the support body 16. When filling in the fluid medium, the fluid medium flows through the radial hole 22 of the support body 16 into the internal volume of the balloon body 2, causing the balloon body 2 to expand. When the filling process is finished, the internal volume of the balloon body 2 has expanded by the volume of the fluid medium received therein. The volume of the fluid medium received therein may be adapted to the treatment and requirements of the patient. It may for instance amount to 75 ml or 100 ml.
When the elastic material of the balloon body 2 expands, this generates a restoring force that serves as a pumping pressure when delivering the fluid medium. In order to generate a pumping pressure that is as constant as possible during the entire delivery time, it is necessary for the balloon body 2 to expand constantly when filling in the fluid medium. In order to ensure an expansion of the balloon body 2 that is as constant as possible, the tube body 10 of the balloon body 2 is provided with longitudinal ribs. The longitudinal ribs run continuously along the longitudinal axis of the tube body 10 along the entire length thereof. The longitudinal ribs stabilize the tube body 10 along a longitudinal axis. This allows only individual segments between the longitudinal ribs to be expanded, which improves the expansion behavior of the balloon body 2 and, consequently, the dosage behavior of the infusion pump.
The stability and the expansion behavior of the balloon body 2 can be improved even more by combining internal longitudinal ribs 32 and external longitudinal ribs 34. As shown in
Number | Date | Country | Kind |
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10 2016 212 579.6 | Jul 2016 | DE | national |