Abstract: A blood pumping system and method in which a selective backflow warning is generated in response to the detection of a backflow condition only in the absence of electrical interference that could cause the generation of a false backflow warning. Detection of a backflow condition is performed by activating the transmitter and receiver of a flow detector to determine the direction of blood flow and detection of the electrical interference is performed by activating the receiver of the flow detector while the transmitter is not activated. If electrical interference that could cause the generation of a false backflow warning exceeds a threshold, the system does not generate a backflow warning.

Abstract: A simple and inexpensive method and apparatus are provided for increasing the pressure at which fluid may be delivered by a lavage/irrigation system.

Abstract: Systems are disclosed which utilize implanted chemo-sensitive living cells to monitor tissue or blood concentration levels of chemicals. The implanted cells produce a detectable electrical, optical or chemical signal in response to changes in concentration in surrounding medium. The signal is then detected and interpreted to give a reading indicative of blood concentration levels. Capsules containing chemo-sensitive cells and electrodes for detecting electrical activity are also disclosed. Methods of monitoring the concentration are also described utilizing the systems and capsules disclosed.

Abstract: A valve assembly adapted for introduction of surgical instruments into a patient's body includes a valve body formed of a flexibly resilient material which defines an aperture for reception of the instrument. The aperture is configured and dimensioned such that insertion of the instrument into the aperture will cause the resilient material of the valve body to resiliently engage the outer surface of the instrument in a substantially gas tight manner. The valve assembly includes a biasing member for closing the valve body to form a gas tight seal prior to inserting the instrument therethrough.

Abstract: A valve for fluids employs two telescoping parts which cooperate with one another to block fluid flow when pulled partially apart and open a flow path therethrough when pushed together. A plunger component, having a central bore, a closed off end and perforated walls, is slidingly and sealingly received within the collar of the hollow valve body. When the plunger's closed end is pushed far enough into the valve body so as to expose the apertures, fluid is free to flow from within the valve body into the plunger component. When pulled apart so as to cause the perforations to be positioned within the confines of the collar, flow is blocked. An actuation mechanism integrated into a housing serves to automatically pull the valve's components apart to stop flow when its cover is swung open and conversely causes the two components to be pushed together to open flow when the cover is closed.

Abstract: A drip detecting device for detecting drips dropping in a drip cylinder, includes an image detecting portion disposed in the vicinity of the outer wall surface of the drip cylinder for detecting the state in the drip cylinder as an image, and a drip detecting portion for detecting a drip dripping in the drip cylinder on the basis of the image. Disclosed also is a drip alarming device which includes a drip rate detecting portion for detecting the rate of dripping on the basis of the data detected by the drip detecting device, a determining portion for determining whether the detected dripping rate is proper, and a generating portion for generating an alarm in accordance with the result of the determination. A drip rate control device also is detected which has a drip rate detecting portion for detecting the rate of dripping on the basis of the data detected by the drip detecting device, and a drip rate control portion for controlling the drip rate to a required rate.

Abstract: A homeostatic organ preservation system includes structure for defining a chamber for holding a donor organ, and a pump for providing a perfusion solution to the organ. A first conduit is coupled to the pump and is adapted to be coupled to the organ. The first conduit provides perfusion solution from the pump to the organ. A second conduit is coupled to the pump and to the organ chamber. The second conduit returns perfusion solution from the organ chamber to the pump. A pressure sensor is coupled to the first conduit to sense the pressure of the perfusion solution in the first conduit. The pressure sensor provides an output signal which is indicative of the vascular resistance of the organ. A pump control circuit is also included. The pump control circuit is responsive to the output signal of the pressure sensor to raise and lower the pump pulse rate respectively in response to a decrease and increase in the organ vascular resistance.

Abstract: An endoscopic electrosurgical suction-irrigation instrument with insertable probes and attachments is disclosed. The instrument has a fluid chamber sealed at its proximal end with a slit valve for receiving the probes and connected at its distal end to a cannula through which the inserted probes extend. The fluid chamber is selectively provided with suction and/or irrigation and includes an electrical contact for supplying voltage to an inserted electrosurgical probe. Depending on the probe configuration suction and/or irrigation is provided in an annular space between the probe and the cannula or through the probe. Valves, connectors and switches for use with the instrument are also disclosed.

Abstract: A closed-end catheter having a flat-surfaced valve positioned in a recess about the distal portion of the catheter for preventing retrograde flow of blood therethrough when positioned in a blood vessel of a patient. The valve catheter comprises a flexible material, cylindrical tube having a semi-circular cross-sectional wall extending longitudinally about the distal portion thereof. The laterally facing valve is formed in a planar surface of a flexible material layer attached to the wall in the distal portion of the cylindrical tube. One or more passages extend through the cylindrical tube in which medicaments or fluids can be simultaneously injected or aspirated. The valve is formed by inserting one or more flat-surfaced rods in the passages of the tube to stretch the surrounding wall. A flat-surfaced layer of flexible material is applied over the flat-surfaced rod to the stretched wall.

Abstract: A TROCAR catheter assembly employs a regulated gas flow between a catheter and the inner wall of a cannula sleeve in which the catheter moves. Annular grooves are formed in the wall of the sleeve and the grooves are connected to a source of gas which produces a pressure differential which causes gas to flow in a manner to control passage of gas to or from a body cavity in which the sleeve is inserted. In one embodiment, one of the annular grooves is connected to a bladder which is inflated to seal the entire opening defined by the inner wall of the sleeve when the catheter is absent.

Abstract: In the method and dissolving therapeutic apparatus for dissolving a coagulation within a living body, a medicinal liquid for dissolving the coagulation within the living body is injected into the living body, the injected medicinal liquid is left within the living body for a predetermined time and the fluid within the living body containing the coagulation dissolved by the medicinal liquid and the medicinal liquid is substantially all discharged out of the living body. A series of steps including at least respective injecting, leaving and discharging steps is repeated. Preferably, vibrating waves are radiated toward the coagulation during the leaving step.

Abstract: A double lumen gastric tube including a valve to prevent gastric reflux or leakage through the vent lumen thereof. The gastric tube also includes an adaptor which allows fluid injection through the tube without removing the valve. The valve allows the passage of air into the vent lumen when atmospheric pressure exceeds stomach pressure. When stomach pressure exceeds atmospheric pressure the valve prevents flow of fluid through the tube. The adaptor allows fluid to be injected into the vent lumen through the valve.

Abstract: The present invention relates to compositions for killing undifferentiated epithelial cells during cataract surgery on an eye to prevent posterior capsule clouding after the surgery and to a method for performing cataract surgery on an eye including injecting a cell-killing substance between the anterior capsule and the natural lens prior to removing the natural lens from the eye. The cell-killing substance is preferably an acid or base adjusted aqueous solution having a pH in the range between about 1.0 to below 6.5 or about above 7.5 to 14.0; or a hypotonic solution having a salinity less than 0.9% or a pH adjusted hypotonic solution having a salinity less than 0.9% and a pH either below 6.5 or above 7.5. The compositions of the present invention also incorporates a viscoelastic material, a dye or a mixture thereof, in combination with the cell-killing substance.

Abstract: An infusion device with a disposable administration set which is inexpensive to manufacture. In the preferred embodiment of the present invention the disposable administration set has a plurality of elongated cam followers connected to a plate assembly, wherein the cam followers are displaced in a predetermined sequence and forced against a delivery tube by cam means driven by rotary drive means. The disposable administration set is injection molded as a single integral piece. The disposable administration set includes adjustment spacers disposed between the plate assembly and the cam followers which adjust the distance between them to keep the device accurate. In the preferred embodiment of the present invention the cam means are configured to provide fluid delivery at a consistent and uniform rate.

Abstract: A treatment apparatus for removing a coagulum such as a calculus or the like produced in an organism by dissolving it comprises irrigation with a medical fluid by using an irrigation pump and suction of the medical fluid by using a suction pump. In this apparatus, when a switch for stopping treatment is operated, the apparatus is not immediately stopped, but the apparatus is stopped after the medical fluid introduced into the organism has been completely discharged so that no medical fluid harmful to the organism remains in the organism.

Abstract: A device for monitoring a delivery system comprising a volumetric micropump, a measuring element or sensor located in the infusion line, a matching system and an analyzing system. The devices are preferably for use in insulin administration when treating type-I diabetes and in analytical laboratories, the chemical and pharmaceutical industries and other technologies.

Abstract: The invention concerns a surgical apparatus for the irrigation and aspiration of the operative cavity during endoscopic surgery. The apparatus comprises a reservoir of liquid for irrigation of the cavity, a pump for circulating the liquid in the cavity, a pressure measuring and control means, such as a piezometric cell and valve for measuring and controlling pressure in the cavity and a flow control means for controlling the flow of the liquid. The apparatus also provides temperature control means by which the temperature of the liquid may be adjusted, which along with pressure control means and adjustment of pressure of the liquid in the cavity, provides a desired hemostatic effect during the surgical process.

Abstract: An irrigation system for irrigating and pressurizing a body cavity during an endoscopic procedure, such as during arthroscopy, includes a source of irrigation liquid, a pneumatically driven pump for pumping irrigation liquid from the source into the body cavity. The pump develops pulsatile flow and its operation is controlled by a pressure regulator that regulates the pressure of air applied to the pump. The system enables disablement of the pumping function of the pump while permitting gravity flow of irrigation liquid to the body cavity. The pump and associated tubing is inexpensive and adapted for one-time, disposable use.

Abstract: A method and device for protecting the circulatory system of a patient from incurring injury from inadvertent passage of air into the aorta when elevated with respect to and supported by a heart-lung machine and associated nonocclusive pump. This device and method provides positioning a valve means having unidirectional flow properties within the extracorporeal blood line connecting the heart-lung machine and patient. The valve is configured to offer nominal resistance against blood being returned to the patient, while blocking blood flow from the patient to the heart-lung machine.

Abstract: An irrigation system is provided to communicate fluid pressure to a body cavity for diagnostic or surgical proceedings. A pump control unit generates fluid pressure and a monitor control circuit provides feedback to the pump control unit to substantially avoid a build up of excessive fluid pressure within the body cavity. In combination with a hysterscope, the irrigation system extends a uterus in a safe manner so that fluid absorption within the uterus is substantially eliminated.

Abstract: A capacitance-type fluid level sensing system, method, and device is disclosed for determining the amount of fluid in a container, for example, a disposable plastic bag used for intravenous (i.v.) injection or collection of waste from a human body (catheter). In one illustrated embodiment, conductive plates are disposed on the outside of the plastic bag and connected to a circuit for detecting any change in the capacitance of the capacitor formed thereby. In another embodiment, the conductive plates are integrally constructed as part of a surface of the electronic device housing, such that the fluid level can be detected when the housing is affixed directly to the outside of the bag. Alternative annunciation, detection, flow rate calculation, display, and housing features are shown in various embodiments.

Abstract: Surgical procedures on biological tissue are carried out with the aid of a laser with substances being applied to the tissue before or during the treatment and these substances are absorbent in the range of the wavelength of the laser beam. A surgical manipulator can be provided and equipped with suction and irrigation channels and the substances can be directed to one of these channels via a metering unit. The application of substances such as sulfisomidine or sulfacetamide increases the ablation rate and reduces the threshold of the ablation process. At the same time, sensitive structures are protected from the damaging effects of the laser radiation as well as from the stray radiation and fluorescence radiation triggered by the laser radiation during the application of microsurgery to the eye.

Abstract: An electronic controller connected to an electronic infusion pump which regulates the rate at which a drug is infused into a person. A magnetic card reader reads from a magnetic card, the name of the drug, the stock solution, concetration recommended dosage rate and warnings. The weight and the desired dosage rate of the patient is fed by a touch pad to the controller. The controller automatically computes the infusion rate and notifies via a display whether the desired rate exceeds the recommended rate. Also displayed are details about the drug, the length of time the patient has been infused, the amount of drug infused, and the dosage rate since the last rate change.

Abstract: Systems are disclosed which utilize implanted glucose sensitive living cells to monitor blood glucose levels. The implanted cells produce a detectable electrical or optical signal in response to changes in glucose concentration in surrounding tissue. The signal is then detected and interpreted to give a reading indicative of blood glucose levels. Capsules containing glucose sensitive cells and electrodes for detecting electrical activity are also disclosed. Methods of monitoring blood glucose are also described utilizing the systems and capsules disclosed.

Abstract: The present invention pertains to a device for irrigation of and aspiration from body cavities, especially during surgical laparoscopy, comprising a delivery pump and a suction pump and tubing lines, which are connected to these and lead to the body cavity. A device for irrigation of and aspiration from body cavities, which can be operated in a very simple manner and fully meets sterility requirements is provided.

Abstract: Safety enhanced device and method are disclosed for effecting application of a therapeutic agent. A removable and operationally non-volatile programmable element is used to control operation of a therapeutic agent delivery unit. A computer, operationally independent of the delivery unit, is utilized to establish coded information for programming of the programmable element while removed from the delivery unit. Operation of the delivery unit according to the program then established for the programmable element is simulated at the computer prior to actual programming of the programmable element to insure the integrity of subsequent delivery of the therapeutic agent to a patient by the delivery unit. The programmable element effects independent delivery of therapeutic agents in each of a plurality of channels under the control of the programmable element.

Abstract: A programmable infusion system includes a disposable IV tubing apparatus for conveying intravenous fluid from a source to a patient. A compact, portable case has a receptacle for removably receiving a segment of the disposable apparatus. A peristaltic pump is mounted in the case for engaging the segment of the disposable apparatus and pumping intravenous fluid therethrough. A motor is mounted in the case and is connected for driving the pump upon energization thereof. A bar code reader is mounted in an edge portion of the case for sensing a bar code label attached to the source of intravenous fluid, such as a bag. The bar code label represents the prescribed fluid delivery parameters. These are read and displayed in alphanumeric form by the system when the edge portion of the case containing the bar code reader is passed over the label.

Abstract: A medical fluid flow set comprises flexible flow tubing having a plastic "pillow" connected in-line with the flow tubing through opposed, generally parallel first and second longitudinal ports. By this invention, the plastic pillow comprises a single, blow-molded, integral piece with a third port communicating with the pillow at a point between the first and second ports. The third port tube extends laterally outwardly from the pillow and turns, typically by essentially a right angle to define an outer tube end having an axis essentially parallel to the first and second ports. A set branch line may be connected to the outer tube end. Such a pillow is manufactured by blow molding to provide an improved product over the prior art, at less cost.

Abstract: An assembly for the removal and examination of amnioytes in early pregnancy by filtering the amniotic fluid and returning the fluid to the fetus subsequent to filtering wherein a conduit structure has a filter incorporated therein and is constructed to include two different paths of fluid flow, one for drawing off said amniotic fluid through the filter means and one for returning the amniotic fluid subsequent to filtering along a path which bypasses said filter structure.

Abstract: A method and apparatus to evaluate the performance of an implanted medication delivery device such as pumps and ports is described. In the case of a pump, the system measures ambient pressure and obtains two pressure measurements from the implanted device. One of these measurements is device reservoir pressure and the other is based on a disturbance pulse injected into the system at a point downstream of the reservoir. Based on those measurements and input calibration data, an expected flow rate is determined. The expected flow rate together with device refill data is in turn used to determine a normalized flow rate for the in-vivo device. Determinations are then made as to the performance of the reservoir, its pump and the condition of the outlet catheter without explant of the device. In the case of a port, the system measures the catheter resistance based on decay time of a disturbance pulse.

Abstract: A continuous cycle peritoneal dialysis system which includes a source (14) of dialysis fluid, and an inflow line (34) and outflow line (35) connected to a catheter (26) implanted in the peritoneal cavity (28). A fill pump (B) pumps dialysis fluid from the source to the catheter during a fill cycle. A drain pump C pumps fluid from the catheter to a drain during a drain cycle. A function of a volume of the dialysis fluid in the peritoneal cavity is detected by a manometer (D). A process controller (A) controls the fill and drain pumps in response to signals from a high fluid level detector (50) and a low fluid level detector (52) on a fluid column tube (48) to pump a calibrated fill volume of fluid into the cavity and a calibrated drain volume of fluid out of the cavity continuously in alternating fill and drain cycles in a manner that the fluid flows through the cavity generally with zero dwell time.

Abstract: An infusion alarm includes an infusion bag formed between an infusion bottle and a needle or cannula insertable in a patient body, and an exhausting sensor having two leaves pivotally connected with each other for resiliently clamping the infusion bag having two contactors respectively connected to two poles of a power source connected to an alarm, whereby when the infusion liquid is being dripped to be almost exhausted as injected to a patient's body, the two leaves of the sensor originally separated by the clamped infusion bag may be restored to close the two contactors for sounding the alarm and alerting a nurse for renewing the infusion liquid.

Abstract: An apparatus for the biofeedback control of body functions is proposed having at least one sensor for detecting biological body functions, a data memory for storing comparison values, a control unit or microprocessor (9, 16) and a therapy member, the control means (9, 16) activating the therapy system as a function of the measured values detected by the sensor and the comparison values. The therapy systems has a pump for the intravenous, intra-arterial, oral or intraluminal administration and a drug reservoir connected to the pump. The control unit and/or therapy means is provided with a memory, which stores the therapy objectives for the body functions with associated drug doses as a function of the detected measured values and comparison values.

Abstract: Disclosed is a gravity flow fluid balancing system that includes an infusion line to transport an infusate from an infusate supply to a patient's body and an ultrafiltrate line for transporting ultrafiltrate from the body to an ultrafiltrate reservoir. The infusate and ultrafiltrate reservoirs are each connected to a load cell. The load cells are, in turn, connected to a control unit which compares the readings received from the load cells. A clamp, which is controlled by the control unit, controls the flow out of the infusate reservoir into the patient's body. Control of the clamp and fluid flow through the system can be regulated on a weight change basis (infusate - ultrafiltrate) or on an infusion basis.

Abstract: Disclosed is an apparatus and method for exchanging cerebrospinal fluid. The apparatus withdraws cerebrospinal fluid from the lumbar subarachnoid space, filters, cools, pH adjusts and performs diagnostic/monitoring functions on the fluid. It then returns purified and/or artificial spinal fluid to the subarachnoid space. The apparatus monitors fluid temperature and core body temperature. Furthermore, it detects increased subarachnoid hemorrhage or repeat subarachnoid hemorrhage. The apparatus is attached to an indwelling spinal cannula, and can continually exchange cerebrospinal fluid and monitor the patient. The apparatus can be completely controlled by computer with technician supervision for the treatment of patients needing purification of their spinal fluid.

Abstract: A fully automatic organ pressure sensitive apparatus for dislodging and removing obstructions in bodily cavities or organs by both delivering and removing fluid thereto, operable by high rate continuous or intermittent infusion of fluid solvent over a set pressure range to effect rapid dissolution and removal of the obstruction without complications to the patient. By continuous feedback monitoring of fluid pressure in the bodily organ or cavity of interest, the apparatus can constantly vary infusion and aspiration rates to maintain the set passages range. If the pressure persists above or below the set range, the apparatus activates a safety feature leading to a period of maximal aspiration and cessation of infusion, followed by cessation of solvent transfer and triggering of an alarm to alert the operator.

Abstract: An apparatus and method for providing a colonic lavage to a patient comprises a speculum for insertion into the colon of the patient with the speculum being generally tubular and having a tapered end within the colon with opposing openings formed therein and discharge and inlet openings outside the anal canal. The inlet opening is connected to a lavage liquid holding chamber through an inlet conduit and the discharge conduit is connected to a collection chamber through a discharge conduit. The discharge conduit has a resilient collapsible portion that passes through a pinch valve that can be actuated to close the discharge conduit. In operation, lavage liquid is pumped from the holding chamber while the pinch valve is closed causing the colon to fill with liquid. When the colon is full, pumping is discontinued and the pinch valve opened allowing liquid and loosened fecal matter within the colon to be purged through the discharge conduit to the collection chamber.

Abstract: Device and method are disclosed for effecting application of a therapeutic agent. A removable programmable element is used to control operation of a delivery unit, which unit delivers the therapeutic agent to the patient. The programmable element is programmed, while removed from the delivery unit, by a computer that is operationally independent of the delivery unit to insure the integrity of subsequent delivery of the therapeutic agent to the patient by the delivery unit. The delivery unit requires no microprocessor and can include a plurality of channels for effecting independent delivery of therapeutic agents in each channel under the control of the programmable element. The programmable element is programmed with respect to available protocol informaton, including patient history, needs and tolerances, as well as therapeutic agent parameters, to thereby establish a flow profile that is customized for a particular patient during each moment of each day.

Abstract: Apparatus for monitoring fluid flow in dialysis systems include a tube holder for mounting the tube at a predetermined location on a dialysis monitor, a transmitter for transmitting a signal such as ultraviolet light through that location, a receiver for receiving the signal after it has passed through that location, and a sensor for sensing whether the tube is mounted at that location and whether the fluid is contained within the tube in response to the signal received by the receiver.

Abstract: There is disclosed herein a system for providing control of multiple functions needed to perform eye surgery. A microprocessor based system controls a vacuum generation system using venturis and linear valves and a pneumatic system for driving vitrectomy probes and pneumatic scissors in either a variable frequency, multicut mode or a proportional cut mode where the cutting pressure is proportional to the position of a foot operated position sensor. The frequency of the vitrectomy probe cutting action can also be controlled and the level of vacuum can be controlled from a foot operated position sensor which can also be used to turn on or off a fragmentation device. The footswitch can also be used to turn irrigation fluid on or off, and the flow rate can be controlled from a control on the front panel. By making a certain foot motion in any certain aspiration modes, reflux of the aspiration line can be controlled.

Abstract: A suction drainage device is provided, particularly for collecting liquids and any solids that may be carried therewith from a cavity of a body. Suction draws air or other gases from a collection chamber, and liquid and entrained particles from the cavity are drawn into a collection chamber. The device also has a water manometer. A liquid seal is also provided through which is drawn air and other gases from the collection chamber. A fluid control valve-like device is provided between various portions, chambers, and conduits of the device, and preferably between the device itself and atmosphere, such control device preferably being a gas permeable, liquid impermeable membrane, but optionally comprising a baffle. A facility is provided for breaking up bubbles of air at the inlet to the water in the manometer.

Abstract: The principal of total internal reflection is utilized in sounding an alarm in a medical fluid infusion system when a downstream blockage occurs. A miniature prism is mounted in a cavity in a rigid exterior tube. The infusing fluid flows in a plastic tubing along the central channel of the rigid tube. The plastic tubing in the interior of this exterior rigid tube is diametrically expansive with an unpressurized outside diameter which is less than the inside diameter of said rigid exterior tube. A light source and light detector is positioned adjacent to the equilateral planes of the prism mounted in the rigid tube.

Abstract: There is disclosed herein a system for providing control of multiple functions needed to perform eye surgery. A microprocessor based system controls a vacuum generation system using venturis and linear valves and a pneumatic system for driving vitrectomy probes and pneumatic scissors in either a variable frequency, multicut mode or a proportional cut mode where the cutting pressure is proportional to the position of a foot operated position sensor. The frequency of the vitrectomy probe cutting action can also be controlled and the level of vacuum can be controlled from a foot operated position sensor which can also be used to turn on or off a fragmentation device. The footswitch can also be used to turn irrigation fluid on or off, and the flow rate can be controlled from a control on the front panel. By making a certain foot motion in any certain aspiration modes, reflux of the aspiration line can be controlled.

Abstract: A medical drainage and irrigation system employs a reversible peristaltic pump to perform both drainage and irrigation. A motor control system independently controls the duty cycle and flow rate during drainage and irrigation using an electronic control to transfer the pumping direction between drainage and irrigation. A loop comprising a flow control valve assembly and external tubes connected thereto may be removed as an assembly for cleaning or discard.

Abstract: A continuous flow peritoneal dialysis system and process is disclosed which includes a source of sterilized peritoneal dialysis system in the form of a gravity feed head vessel (32). A by-pass valve (34) connects the head vessel to an inflow/outflow directional valve 40 which controls the inflow and outflow of the sterilized dialysis fluid to a peritoneal catheter (12). The peritoneal catheter is implanted into the peritoneal membrane (14) of the peritoneal cavity (15). A connectable/disconnectable inflow line (42) and outflow line (48) are connected to an inflow catheter (44) and outflow catheter (46), respectively, of the double peritoneal catheter (12). A pressure monitor (50) in the outflow line (48) monitors the pressure within the cavity (15) and adjusts the inflow and outflow accordingly to maintain a predetermined volume and pressure of dialysis fluid in the cavity to maintain the membrane (14) properly distended at all times for maximum dialysis efficiency and patient comfort.

Abstract: A drop detecting system has light emitting diodes and phototransistors located on either side of a translucent drip chamber. The phototransistors respond to either the shadow or the reflection from a drop falling through a light beam produced by the light emitting diodes. The electrical response from the phototransistors is conducted to an integrator circuit which generates an electrical signal voltage. A comparator circuit receives the electrical signal voltage from the integrator circuit and outputs a signal indicating the presence of a drop passing through the drip chamber. A drip chamber housing cooperates with the drip chamber to shroud the translucent portion of the drip chamber. Additionally the drip chamber housing provides for the mounting of the light emitting diodes and the phototransistors.

Abstract: A continuous flow peritoneal dialysis system and process is disclosed which includes a source of sterilized peritoneal dialysis system in the form of a gravity feed head vessel (32). A by-pass valve (34) connects the head vessel to an inflow/outflow directional valve 40 which controls the inflow and outflow of the sterilized dialysis fluid to a peritoneal catheter (12). The peritoneal catheter is implanted into the peritoneal membrane (14) of the peritoneal cavity (15). A connectable/disconnectable inflow line (42) and outflow line (48) are connected to an inflow catheter (44) and outflow catheter (46), respectively, of the double peritoneal catheter (12). A pressure monitor (50) in the outflow line (48) monitors the pressure within the cavity (15) and adjusts the inflow and outflow accordingly to maintain a predetermined volume and pressure of dialysis fluid in the cavity to maintain the membrane (14) properly distended at all times for maximum dialysis efficiency and patient comfort.

Abstract: A method and system for continuously monitoring patient heart rate and blood pressure during hemodialysis and for automatically controlling fluid extraction rate and/or dialysate sodium concentration in the event that blood pressure and/or heart rate indicate onset or impending onset of a patient hypotensive episode. A decrease in patient blood pressure below preselected systolic and/or diastolic low alarm limits automatically initiates a second mode of therapeutic intervention wherein sodium concentration in the dialysate is increased for a predetermined time duration. Upon detection of such low blood pressure alarm, or upon detection of an increase in patient heart rate above a preselected alarm limit, the extraction rate of fluids from the patient through the ultrafiltration membrane is reduced in a first mode of therapeutic intervention by reducing such fluid extraction rate to a minimum level.

Abstract: A compact, lightweight, variable rate suction and collection device is provided for the withdrawal and collection of fluid from a patient. The device includes a collection receptacle which is connected to the patient and to a pump through suction inlet, so that suction is created within the collection receptacle whereby fluids from the patient are drawn into the receptacle. A piezoelectric transducer or diaphragm pressure switch senses the suction created while a suction level selector permits an operator to select a given suction pressure within a predetermined range. A control circuit, responsive to the piezoelectric transducer or switch and to the suction level selector, controls the suction created within the receptacle. Among other features, the control circuit provides a selected suction pressure as well as controls delivery of fractional power to the pump motor to reduce noise.

Abstract: A gate or slide valve of molded plastic construction having a flat gate or slide member reciprocable or rotatable in a slot whose widths may vary due to the limitations of the molding process in combination with a flat low-friction laminated seal which is resiliently adjustable to accommodate the aforesaid widthwise variations.