Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B43/00—Machines, pumps, or pumping installations having flexible working members
  • F04B43/12—Machines, pumps, or pumping installations having flexible working members having peristaltic action
  • F04B43/1253—Machines, pumps, or pumping installations having flexible working members having peristaltic action by using two or more rollers as squeezing elements, the rollers moving on an arc of a circle during squeezing
• • 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
  • A61M60/00—Blood pumps; Devices for mechanical circulatory actuation; Balloon pumps for circulatory assistance
  • A61M60/10—Location thereof with respect to the patient's body
  • A61M60/104—Extracorporeal pumps, i.e. the blood being pumped outside the patient's body
  • A61M60/109—Extracorporeal pumps, i.e. the blood being pumped outside the patient's body incorporated within extracorporeal blood circuits or systems
• • 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
  • A61M60/00—Blood pumps; Devices for mechanical circulatory actuation; Balloon pumps for circulatory assistance
  • A61M60/20—Type thereof
  • A61M60/247—Positive displacement blood pumps
  • A61M60/253—Positive displacement blood pumps including a displacement member directly acting on the blood
  • A61M60/268—Positive displacement blood pumps including a displacement member directly acting on the blood the displacement member being flexible, e.g. membranes, diaphragms or bladders
  • A61M60/279—Peristaltic pumps, e.g. roller pumps
• • 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
  • A61M60/00—Blood pumps; Devices for mechanical circulatory actuation; Balloon pumps for circulatory assistance
  • A61M60/40—Details relating to driving
  • A61M60/424—Details relating to driving for positive displacement blood pumps
  • A61M60/438—Details relating to driving for positive displacement blood pumps the force acting on the blood contacting member being mechanical
  • A61M60/441—Details relating to driving for positive displacement blood pumps the force acting on the blood contacting member being mechanical generated by an electromotor
• • 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
  • A61M60/00—Blood pumps; Devices for mechanical circulatory actuation; Balloon pumps for circulatory assistance
  • A61M60/80—Constructional details other than related to driving
  • A61M60/835—Constructional details other than related to driving of positive displacement blood pumps
  • A61M60/837—Aspects of flexible displacement members, e.g. shapes or materials
• • 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
  • A61M60/00—Blood pumps; Devices for mechanical circulatory actuation; Balloon pumps for circulatory assistance
  • A61M60/80—Constructional details other than related to driving
  • A61M60/845—Constructional details other than related to driving of extracorporeal blood pumps
  • A61M60/851—Valves

Definitions

• a roller pump is used.
• a pump is constituted by a flexible pipe, in which the patient's blood circulation is bypassed and by rollers, situated at the end of rotary arms, which successively crush said tube, a portion of the length of which is arranged in an arc of circle whose center is located on the axis of rotation of said arms.
• Such a pump has a flow rate which is substantially equal to that supplied by a normal core.
• the pressure of the fluid delivered by the pump is barely equal to that of the diastolic pressure.
• Such a pump ensures a practically continuous flow while the blood circulation has a flow having a pulsed characteristic. It follows that if these pumps can be used without major dangers for the patient for a very short time, that of a surgical intervention gicale for example, they cannot be used to provide continuous assistance.
• a pump which can be called “helical pump” constituted in its simplest form by a pipe wound so as to form a helical turn pivoting about its axis alternately in one direction and in the other, the inlet and the output of the pump extending along said axis. It emerges from the mathematical studies carried out on such a pump that it makes it possible to obtain a high pressure but with a very low flow rate.
• this pump cannot be used to provide extra-bodily blood circulation. Indeed, if it allows to easily reach a pressure equal to that of the systolic pressure the maximum flow remains much lower than the diastolic flow.
• the pump of the invention which overcomes these drawbacks, is constituted by the association of a roller pump and a helical pump, the blood flow first passing through the roller pump.
• the pump of the invention exhibits a flow rate and a pressure which can vary between the usual values specific to normal blood circulation and this, without carrying out untimely hemolysis or requiring the supply of foreign blood in due to the small internal volume of the pump.
• the invention also relates to a pump, of the type described above, which can be used to assist a patient whose heart is in operation. It should be noted that in assistance the roller pump is not essential. In a simplified manner, this problem manifests itself mechanically by the fact that the frequency and the amplitude of the oscillations of the drum of the helical pump must be able to vary at will.
• the drum of the helical pump is driven by means of an electric stepper motor housed inside said drum.
• the invention remedies these drawbacks in the following manner: a) at the level of the inlet pipe, This pipe passes through a nozzle made integral with the drum and opens into an annular chamber formed by the combination of a circular groove provided on said nozzle, a fixed ring comprising the inlet orifice and two seals, ensuring the 'sealing between the ring and the tip, arranged on either side of said groove. b) at the outlet pipe.
• the aforementioned endpiece is axially traversed by the, conduit and is placed in coincidence with an outlet orifice provided in the bottom of a fixed housing made integral with the aforementioned ring and to which the outlet orifice is connected, said housing being closed by a seal cooperating with it and the end piece while providing around the latter an annular chamber.
• Figure 1 is a schematic perspective view of a pump according to the invention
• Figure 2 is an enlarged view of detail A of Figure 1;
• Figure 3 is a longitudinal sectional view of an embodiment of a helical pump.
• the pump consists mainly of a flexible pipe 1, having an internal diameter of approximately ten millimeters.
• This pipe is maintained in a circular arc 2 and is subjected to one successive action of rollers 3 carried by arms 4, the center of the circular arc being located on the axis 5 of rotation of said arms, the whole constituting a conventional roller pump.
• the pipe 1 is wound on a drum 6 so as to constitute at least one turn 7.
• the cana lization 1 enters the drum 6 and leaves it so that its axis is coincident with that of said drum.
• the coil 7 is driven, around its axis, by an oscillating movement by means of a connecting rod-crank device 8-9, the assembly 6 to 9 constituting a helical pump.
• the pump of the invention makes it possible, at any time, to vary one of the three characteristics above.
• the flow rate can vary depending on the speed of rotation of the rollers.
• the pulsation depends on the frequency of the oscillations of the drum 6, therefore on the speed of rotation of the crank 9 which can be easily adjusted.
• the pressure varies as a function of the amplitude of the oscillations which depends on the length a of the crank 9.
• an electric actuator 10 can be used, as shown in FIG. 1.
• the pump which has just been described makes it possible to produce a blood circulation whose pulsed flow rate varies between a zero value and a maximum value.
• this valve is constituted by a flexible tube, flattened, the two walls of which are normally in contact with one another (FIG. 2). It follows from the above explanations that the pump of the invention can be used to provide continuous circulatory assistance, but experience has shown that, in this case, it was preferable to simply use a helical pump conforming to that shown. in figure 3.
• the pump consists essentially of a pipe 12 helically wound on a drum 13.
• the drum 13 is driven in rotation by a stepping electric motor 14 housed inside said drum and made integral with a frame 15.
• the drum 13 has an endpiece 16 which can rotate freely in a bearing 17 carried by the frame 15.
• the endpiece 16 has an axial outlet duct 18 and an inlet duct 19.
• the duct 19 opens, by means of a groove 20 provided on the endpiece 16, into an annular chamber 21 formed by the cooperation of said groove, of a ring 22, made integral with the bearing 17 . and two lip seals 23.
• the chamber 21 communicates with the inlet 24 by means of a radial hole 25 in the ring 22.
• the conduit 18 opens in coincidence with the outlet orifice 26 provided in the bottom of a fixed casing 27 and made integral with the ring 22.
• the seal between the housing 27 and the endpiece 16 is ensured by a lip seal 28 sealing the annular space formed between said endpiece and the internal periphery of said housing while forming a chamber 29 sealing.
• the pump which has just been described draws blood into the cardiac chambers and reduces the work of the heart by achieving a double assistance in flow and in pressure.
• This pump allows on the one hand, to decrease the ventricular flow and, on the other hand, the telediastolic and systolic pressures.
• the inlet 24 can be arranged, along the axis of the drum 13, opposite the end piece 16, the seal being produced by a rotary joint similar to that 16-27 -28 described above.
• roller pump described with reference to Figures 1 and 2 can be connected bypass to the input 24 and only intervene in the event of sudden failure of the heart muscle.

Landscapes

• Health & Medical Sciences (AREA)
• Engineering & Computer Science (AREA)
• Heart & Thoracic Surgery (AREA)
• Mechanical Engineering (AREA)
• Anesthesiology (AREA)
• Cardiology (AREA)
• Biomedical Technology (AREA)
• Hematology (AREA)
• Life Sciences & Earth Sciences (AREA)
• Animal Behavior & Ethology (AREA)
• General Health & Medical Sciences (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• General Engineering & Computer Science (AREA)
• External Artificial Organs (AREA)

Applications Claiming Priority (4)

Publications (1)

Family

ID=26221980

Family Applications (1)

Country Status (3)

Families Citing this family (2)

Family Cites Families (4)

• 1981
  • 1981-09-11 JP JP56502993A patent/JPS57501363A/ja active Pending
  • 1981-09-11 EP EP81902623A patent/EP0059743A1/de not_active Withdrawn
  • 1981-09-11 WO PCT/FR1981/000117 patent/WO1982000956A1/en not_active Application Discontinuation

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events