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
  • A61M1/00—Suction or pumping devices for medical purposes; Devices for carrying-off, for treatment of, or for carrying-over, body-liquids; Drainage systems
  • A61M1/14—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis
  • A61M1/16—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis with membranes
  • A61M1/1654—Dialysates therefor
  • A61M1/1656—Apparatus for preparing dialysates
• • 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
  • A61M1/00—Suction or pumping devices for medical purposes; Devices for carrying-off, for treatment of, or for carrying-over, body-liquids; Drainage systems
  • A61M1/14—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis
  • A61M1/15—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis with a cassette forming partially or totally the flow circuit for the treating fluid, e.g. the dialysate fluid circuit or the treating gas circuit
  • A61M1/152—Details related to the interface between cassette and machine
  • A61M1/1524—Details related to the interface between cassette and machine the interface providing means for actuating on functional elements of the cassette, e.g. plungers
• • 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
  • A61M1/00—Suction or pumping devices for medical purposes; Devices for carrying-off, for treatment of, or for carrying-over, body-liquids; Drainage systems
  • A61M1/14—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis
  • A61M1/15—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis with a cassette forming partially or totally the flow circuit for the treating fluid, e.g. the dialysate fluid circuit or the treating gas circuit
  • A61M1/153—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis with a cassette forming partially or totally the flow circuit for the treating fluid, e.g. the dialysate fluid circuit or the treating gas circuit the cassette being adapted for heating or cooling the treating fluid, e.g. the dialysate or the treating gas
• • 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
  • A61M1/00—Suction or pumping devices for medical purposes; Devices for carrying-off, for treatment of, or for carrying-over, body-liquids; Drainage systems
  • A61M1/14—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis
  • A61M1/15—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis with a cassette forming partially or totally the flow circuit for the treating fluid, e.g. the dialysate fluid circuit or the treating gas circuit
  • A61M1/154—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis with a cassette forming partially or totally the flow circuit for the treating fluid, e.g. the dialysate fluid circuit or the treating gas circuit with sensing means or components thereof
• • 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
  • A61M1/00—Suction or pumping devices for medical purposes; Devices for carrying-off, for treatment of, or for carrying-over, body-liquids; Drainage systems
  • A61M1/14—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis
  • A61M1/15—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis with a cassette forming partially or totally the flow circuit for the treating fluid, e.g. the dialysate fluid circuit or the treating gas circuit
  • A61M1/155—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis with a cassette forming partially or totally the flow circuit for the treating fluid, e.g. the dialysate fluid circuit or the treating gas circuit with treatment-fluid pumping means or components thereof
• • 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
  • A61M1/00—Suction or pumping devices for medical purposes; Devices for carrying-off, for treatment of, or for carrying-over, body-liquids; Drainage systems
  • A61M1/14—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis
  • A61M1/15—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis with a cassette forming partially or totally the flow circuit for the treating fluid, e.g. the dialysate fluid circuit or the treating gas circuit
  • A61M1/156—Constructional details of the cassette, e.g. specific details on material or shape
  • A61M1/1566—Means for adding solutions or substances to the treating fluid
• • 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
  • A61M1/00—Suction or pumping devices for medical purposes; Devices for carrying-off, for treatment of, or for carrying-over, body-liquids; Drainage systems
  • A61M1/14—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis
  • A61M1/15—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis with a cassette forming partially or totally the flow circuit for the treating fluid, e.g. the dialysate fluid circuit or the treating gas circuit
  • A61M1/159—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis with a cassette forming partially or totally the flow circuit for the treating fluid, e.g. the dialysate fluid circuit or the treating gas circuit specially adapted for peritoneal dialysis
• • 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
  • A61M1/00—Suction or pumping devices for medical purposes; Devices for carrying-off, for treatment of, or for carrying-over, body-liquids; Drainage systems
  • A61M1/14—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis
  • A61M1/28—Peritoneal dialysis ; Other peritoneal treatment, e.g. oxygenation
• • 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
  • A61M1/00—Suction or pumping devices for medical purposes; Devices for carrying-off, for treatment of, or for carrying-over, body-liquids; Drainage systems
  • A61M1/14—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis
  • A61M1/28—Peritoneal dialysis ; Other peritoneal treatment, e.g. oxygenation
  • A61M1/281—Instillation other than by gravity
• • 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
  • A61M1/00—Suction or pumping devices for medical purposes; Devices for carrying-off, for treatment of, or for carrying-over, body-liquids; Drainage systems
  • A61M1/14—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis
  • A61M1/28—Peritoneal dialysis ; Other peritoneal treatment, e.g. oxygenation
  • A61M1/282—Operational modes
• • 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
  • A61M39/00—Tubes, tube connectors, tube couplings, valves, access sites or the like, specially adapted for medical use
  • A61M39/10—Tube connectors; Tube couplings
• • 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
  • A61M1/00—Suction or pumping devices for medical purposes; Devices for carrying-off, for treatment of, or for carrying-over, body-liquids; Drainage systems
  • A61M1/14—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis
  • A61M1/15—Dialysis systems; Artificial kidneys; Blood oxygenators ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis with a cassette forming partially or totally the flow circuit for the treating fluid, e.g. the dialysate fluid circuit or the treating gas circuit
  • A61M1/156—Constructional details of the cassette, e.g. specific details on material or shape
  • A61M1/1565—Details of 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
  • A61M2205/00—General characteristics of the apparatus
  • A61M2205/12—General characteristics of the apparatus with interchangeable cassettes forming partially or totally the fluid circuit
  • A61M2205/128—General characteristics of the apparatus with interchangeable cassettes forming partially or totally the fluid circuit with incorporated 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
  • A61M2205/00—General characteristics of the apparatus
  • A61M2205/33—Controlling, regulating or measuring
  • A61M2205/3331—Pressure; Flow
  • A61M2205/3344—Measuring or controlling pressure at the body treatment site
• • 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
  • A61M2205/33—Controlling, regulating or measuring
  • A61M2205/3331—Pressure; Flow
  • A61M2205/3351—Controlling upstream pump pressure
• • 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
  • A61M2205/33—Controlling, regulating or measuring
  • A61M2205/3331—Pressure; Flow
  • A61M2205/3355—Controlling downstream pump pressure
• • 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
  • A61M2205/33—Controlling, regulating or measuring
  • A61M2205/3379—Masses, volumes, levels of fluids in reservoirs, flow rates
• • 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
  • A61M2205/58—Means for facilitating use, e.g. by people with impaired vision
  • A61M2205/581—Means for facilitating use, e.g. by people with impaired vision by audible feedback
• • 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
  • A61M2205/58—Means for facilitating use, e.g. by people with impaired vision
  • A61M2205/583—Means for facilitating use, e.g. by people with impaired vision by visual feedback

Definitions

• This invention relates to a new machine and method for carrying out automated peritoneal dialysis (PD) .
• peritoneal membrane In PD, the peritoneal membrane is exposed to the external environment every time a catheter is connected or disconnected from the solution supply, making infection (peritonitis) a significant problem.
• the most popular osmotic agent used in PD dialysates is glucose, Glucose can be absorbed by the body via the peritoneum membrane. This can result in patient obesity and its accompanying complications.. Moreover, heat sterilization of the dialysate which contains glucose produces harmful glucose byproducts .
• APD modality of treatment In a continuing effort to provide adequate PD treatment for the varied population of ESRD patients, clinicians have developed a number of different forms of the APD modality of treatment. These include the APD modalities of:
• IPD Intermittent Peritoneal Dialysis
• NPD Nightly Peritoneal Dialysis
• Applicant's overall objective was to provide an automated peritoneal dialysis machine capable of fully “customizing” the composition of dialysate delivered to a patient to meet his or her immediate physiological needs and, to that same end, capable of monitoring the effectiveness of treatment during the treatment process and use this diagnostic information to optimise the customisation process.
• Figure 1 is a schematic representation of the first "basic" APD machine according to the present invention.
• Figure 2 schematically illustrates one of the liquid input/output ports and a portion of the occluding mechanism in the machine at Figure 1.
• Figure 5 is a graphical representation of the volume of fluid removed to stabilize pressure as a function of time during the DWELL period of a dialysis cycle, as measured using APD apparatus according to the present invention.
• Figure 6 is a schematic illustration of a second embodiment of APD machine according to the present invention.
• Figure 7 is a schematic illustration of a second embodiment of APD machine according to the present invention.
• Figure 8 is a preferred version of the apparatus embodiment of Figure 7, in which components are structurally integrated into a compact cartridge.
• Figure 9 is a schematic illustration of a fourth embodiment of apparatus according to the present invention.
• FIG. 1 A "basic" layout of components of apparatus according to the present invention is illustrated schematically in Figure 1.
• the apparatus is connected to the peritoneal cavity of patient 10 by means of a patient tubing line 12, through which fresh fluid is infused and spent fluid is withdrawn.
• Containers (solution bags) S ⁇ , S 2 carry sterile PD solutions of two different electrolyte compositions and are connected to cartridge inputs 1 and 2 by tubing lines L ⁇ and L 2 , respectively.
• In-line heaters 13 are provided, as is conventional in PD apparatus, to warm the sterile PD solutions to body temperature.
• Containers S ⁇ and S 2 could alternatively carry standard PD solutions (glucose or similar as the osmotic agent) .
• Input 3 of manifold 14 is connected by line L 3 to a container Gi of highly concentrated sterile osmotic agent (glucose solution or other known osmotic agent) .
• Apparatus according to the present invention includes a precise metering pump P- x whose operation is described in more detail below.
• Aforementioned patient line 12 is connected to input 7, while a drain line 15 is connected to port 8.
• a pressure transducer means 17 is preferably included, the signal from which is monitored by electronic control means for the apparatus (not shown) .
• FIG. 3 shows an exploded view an assembly of plungers 22 and 22c, springs 22a and 22b and motors 23 for assembly of an occlusion mechanism of the manifold of automated PD apparatus according to the present invention.
• plungers 22 and plunger springs 22b are first inserted into manifold 14c.
• Cams 23a attached to individual small rotary motors 23 are inserted into the manifold, so that the plungers are retained inside the manifold by the cams and ride directly on the cams.
• the small springs 22a and corresponding plunger heads 22c are inserted from the top into respective plungers 22 through the manifold. All the motors 23 are mounted on a motor mounting plate 24. Two screws 24a are used to secure motor mounting plate 24 to manifold 14c.
• the machine will be controlled by microprocessor means (not shown) , having stored memory for on-line monitoring of information and for programming of set operational parameters .
• a removable memory card can also be incorporated to ensure easy collection and transfer of treatment data for the patients.
• an interactive voice interface and visual and audio alarm systems can be incorporated to simplify the diagnosis of problems during and after PD treatments .
• metering pump PI For efficient operation in drawing calibrated volumes of fluid from container bags and infusing the withdrawn fluid to target locations, whether the container bags and the target locations are vertically above or below the machine, it is essential that metering pump PI provide positive displacement of fluid and have a known volumetric displacement.
• a variable volumetric displacement mechanism included in the metering pump PI. Variable displacement was achieved with controlled linear translation of a volume displacement member. This type of motion was achieved by coupling a worm gear to the output driveshaft of an electric motor. The controlled rotary motion of the electric motor is then smoothly translated into a controlled linear motion which in turn will adjust the volumetric displacement of the pump.
• a common example of this type of metering pump is a syringe pump with controlled linear translation of the plunger in the barrel of the syringe.
• the linear motion (volume displacement) of a metering syringe pump was calibrated in the following manner.
• the internal shaft on the electric motor was digitally encoded. Its rotary position was optically sensed thus generating a set of electrical pulses whose number were directly proportional to linear displacement of the worm gear.
• One particular configuration which was used in this way gave a fluid displacement of 20cc for each 2.15 inches of linear travel of the worm gear.
• the lead screw of the worm gear had a lead of 0.12 inches and was driven through a gear box (gear ratio 81:1) .
• FIG 4 A graphical example of such a predetermined state is shown in Fig 4 at point P 2 .
• the intraperitoneal pressure will increase slowly from T 0 to Ti and in proportion to the filled volume.
• the machine will be programmed to remove enough fluid to back off the pressure from the maximum P 2 to a safe and controlled pressure level P x . This would be the steady state pressure for the monitoring process.
• the official DWELL period then begins at T 2 .
• ports #6 and #7 are opened.
• the metering pump PI draws the spent fluid from the patient and into the syringe. This volume is measured as it is being withdrawn.
• port #7 closes and port #8 opens .
• the pump PI reverses its direction and pushes the waste fluid from the syringe through the drain line and into a receptacle for spent dialysate. This is operated until all the fluid is drained out or the pressure registers negative, or until the end of the set DRAIN time. The final UF is then determined by the machine .
• FIG. 5 Another important characteristic of this invention is its ability to make decisions based on real-time physiological needs of a patient or provide previously unattainable clinical information.
• the invention will allow the normal set DWELL time (T 2 to T 3 ) to be rationally adjusted. At maximum UF volume, V m , the dialysis fluid has reached equilibrium with the plasma in the peritoneal membrane. Therefore anytime beyond T x , would be treatment time wasted.
• a clinician could either program the machine to automatically drain the patient of the spent fluid and introduce fresh fluid for better dialysis or use the information to set more effective DWELL time for the next treatment .
• the set DWELL time terminates at the rising phase of the ultrafiltration curve, then the dialysate is not being utilized properly.
• This graph also reflects real time solute and fluid transport rates of the peritoneal membrane for any given dialysate formulation. That is, the greater the efficiency of the peritoneal membrane the greater the initial slope of the ultrafiltration curve and or the faster time T x is achieved. For the first time clinicians will be able to quantify the transport characteristics of the membrane on-line and use this information to directly control the machine or allow the machine to make the necessary adjustments automatically.
• the later determines the ratio of dialysate-to-plasma (D/P) of a given solute and is the one most commonly used to assess patients . At best this is performed once a month.
• D/P dialysate-to-plasma
• Combining the unique ability of apparatus according to the present invention to secure a sample of the fluid during DWELL at known correlated points on the ultrafiltration curve clinicians will be better able to properly evaluate the PD treatment in vivo. This represents a major advance in the art of PD treatment .
• a related clinical advantage is that clinicians will immediately be able to correlate changes in ultrafiltration curve with the type of medication or additive used during a treatment cycle.
• the pressure monitoring activities used to control the UF using a machine according to the present invention makes it possible to perform a true tidal peritoneal dialysis.
• the actual volume of fluid in the cavity is the same as the initial fill volume. This volume is known.
• an APD machine will be able to use the actual volume of fluid in the peritoneal cavity and not a pre-estimated amount to determine the actual tidal withdrawal and refill volumes. This is a major improvement in the art.
• additional detectors and sensors may be included in the system and their signals taken into account to a programme microprocessor or diagnostic and therapeutic advantage.
• a turbidimeter including a light source and light detector monitoring the clarity of the effluent during DRAIN can give early detection of the onset of infection. If patient line 12 is passed between such a light source and light detector, it will be possible to detect whether or not the patient's effluent is cloudy during DRAIN, owing to an onset of peritonitis (production of enhanced level of light-scattering white blood cells brought about by infection) . The detector will transmit this information to the microprocessor and audio and visual alarms may be initiated, the machine triggered to empty metering pump PI and a sample of cloudy effluent collected for further analysis .
• the "basic" machine shown in Figure 1 employs a metering pump to draw and deliver the apportioned dialysate components
• the arrangement could be used without a metering pump at all, but employing a weighing system and gravity for the discharge of sterile fluids and medications from container bags supported vertically above the patient, with a weigh bag located below the patient for determining the volume.
• FIG. 6 A second embodiment of a PD apparatus according to the present invention is illustrated schematically in Figure 6.
• the same reference numerals are used in Figure 6 and in the below-discussed Figures 7 and 8 to identify parts of the apparatus which are entirely analogous and co-functional with like-numbered components of the basic machine shown in Figure 1.
• the second preferred embodiment as shown in Fig 6. depends on pump PI for achieving compact arrangement and ease of clinical use and uniqueness in portability.
• the cartridge is divided into two distinct chambers 14a and 14b.
• the first chamber houses ports #1, #2, #3, #4, and #5.
• the second chamber houses ports #6, #7, and #8.
• the ports #4 and #7 are now connected to the metering pump PI via one way valves Vi and V 2 for fluid inflow and outflow respectively.
• plungers #4, #5, #7, and #8 are opened.
• the spent fluid from the patient is drawn into PI through the patient line, the pressure transducer 17, through #5, #4 and Valve V : .
• the syringe PI measures the drawn in fluid accordingly.
• the feedback of the pressure transducer regulates the rate of fluid drawn in by Pi from the patient.
• PI is emptied through V 2 , plungers #7 and #8 to the final drain. All the previously mentioned activities are equally applicable to this version.
• Plungers #4 and #7 are not strictly necessary, because, with plungers #s 1, 2, 3, 5, 6 and 8 all closed, the metering pump is isolated and there is no movement of fluid.
• a machine according to this second embodiment could be operated from a normal table top or a short stand, with the solutions and medications located conveniently below the main machine.
• the machine could even be operated at the floor level .
• the positive displacement pump PI ensures that the efficiency of the delivery system does not depend upon the relative vertical positions of the solutions, the patients and/or the final drain, as is the case in gravity-fed cyclers. This therefore makes the new machine universal for patients on normal beds, hospital beds or lying on floor mats.
• Pressure in the lines, and hence in connected bags, or in the patient and in the drain line are all monitored by opening the appropriate port.
• the pressure readings could be used to detect other important conditions in addition to all those already discussed under the previous versions; the detection of these, (a) empty solution bags (S, G : , G 2 & i) (b) obstructions in the drain line and (c) obstructions in the patient line.
• a "compact cartridge” version of the system of Figure 7 is as shown in Figure 8.
• the occlusion block 14, the heater and metering pump PI are all integrated into a single compact cartridge.
• the heating chamber is divided into two sections : the initial heater chamber 13a that houses the incoming cold solution, and the corrugated heater section 13b that directs the fluid path to ensure proper heating of the solution.
• the output of the heater is attached to port #1.
• a preferred embodiment of the new APD apparatus is as shown in Figure 9.
• the operation of this embodiment is the same as the one discussed above for the third version in Figure 7, except in this embodiment there are two additions, namely (a) effluent detector 28 and (b) sample collector port (at #6) .
• the drain line 15 is now located at port #7.
• the effluent detector comprises of a light source 28a facing a light detector 28b. Variations in the light intensities are detected by the light detector and the signals transmitted to microprocessor for the appropriate actions.
• the patient line 12 passes between the light source 28a and the light detector 28b of the effluent detector 28.
• the light beam to the light detector is diffused.
• the detector transmits the message accordingly to the microprocessor. Both audio and visual alarms are initiated.
• the machine automatically, at the point of emptying the metering pump PI, opens port #6 and sends a sample of the cloudy effluent solution into the sample collector container 30 (which could be a bag or a syringe) . Then port #6 will be closed and the normal drain procedure will be continued by operating port #7.
• the effluent detector similarly, will detect excessive amount of blood in the effluent (usually with new catheter operations or with new catheter break-ins) , and could be programmed to automatically reduce the amount of heparin additive and or reduce the dialysate infusion volumes.

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• 1997
  • 1997-07-28 CA CA002211848A patent/CA2211848C/en not_active Expired - Lifetime
• 1998
  • 1998-07-27 WO PCT/CA1998/000722 patent/WO1999006082A1/en not_active Application Discontinuation
  • 1998-07-27 AU AU85257/98A patent/AU8525798A/en not_active Abandoned
  • 1998-07-27 EP EP98936046A patent/EP0999862A1/de active Pending
  • 1998-07-27 JP JP2000504893A patent/JP4070953B2/ja not_active Expired - Lifetime
  • 1998-07-27 CN CNB988091062A patent/CN1185022C/zh not_active Expired - Lifetime
  • 1998-07-27 KR KR1020007000997A patent/KR20010022416A/ko not_active Application Discontinuation
• 2001
  • 2001-05-14 HK HK01103319A patent/HK1032758A1/xx not_active IP Right Cessation

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