Abstract: A surgical irrigation apparatus includes a disposable assembly and a reusable assembly. The disposable assembly includes an irrigation fluid pump and a handpiece having a supply passage for delivery of irrigation fluid to the surgical site. The re-usable assembly includes a motor and a power source. The power is transferred from the motor to the pump with a magnetic coupler or other suitable device. The re-usable assembly is isolated from irrigation fluid in the disposable assembly. All of the electrical components of the apparatus are contained in the re-usable assembly. There are no electrical components in the disposable assembly. A sterile disposable assembly may be assembled in the operating room with an unsterilized re-usable assembly.

Abstract: A phacoemulsification instrument that significantly reduces infusion fluid leakage by providing a silicone sleeve with a built in reinforcing member. Also, the sleeve has only a single infusion hole in order to provide better infusion fluid flow without causing turbulence in the eye. In addition, the present invention provides either a valve or a variable aperture aspiration tube in order to regulate the aspiration rate. Also, the present invention includes a single aspiration hole at the tip in order to amplify flow coming to the tip. To assist in cataract removal, the tip may be provided with a variety of different barrier and baffle configuration. A handpiece includes a variable capacity reservoir in the infusion line to account for surges in the aspiration line. The needle includes steps, angles and barriers to focus ultrasonic energy to aid in emulsifying nuclear tissue and to aid in pushing emulsified material in the direction of aspiration flow.

Abstract: A pump assembly for ambulatory peritoneal dialysis transfer procedures includes a portable power supply geared to drive a high-volume peristaltic pump. A cassette of the pump comprises an encasement; tubing including an inner portion positioned within the encasement, a patient-side portion for connection to an indwelling peritoneal dialysis catheter and an opposing portion connectable to a system for containment and communication of a peritoneal dialysis solution which may be one single-compartment bag assembly; a safety valve for selectively occluding and permitting the communication of the solution through the inner portion; and a filter preferably interposed along the patient-side portion which filters air and particles from peritoneal dialysate that is flowing toward a patient and which allows peritoneal dialysate to flow substantially freely and unfiltered away from the patient.

Abstract: A whole blood collection system includes an automated pump/control unit and an accompanying disposable blood set. When combined and connected to a source of anticoagulant, these elements allow automatic priming of the blood set with anticoagulant and automatic collection of anticoagulated blood product according to three different collection modes. The unit's pump and the blood set are specially designed to cooperate during the collection process to assure that the collected product has a precise blood to anticoagulant ratio. During the collection procedure, the pump/control unit automatically collects data relating to the procedure. Additional data specifically identifying components of the blood set, such as the blood collection bag, along with identification data on the donor's registration form may be scanned into the pump/controller unit by a scanner associated with the unit; this facilitates positive sample identification and tracking.

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 displace in a predetermined sequence and forced against a delivery tube by cam means driven by rotary drive means. The device also includes an optical occlusion sensor which is synchronized to operate in phase with the movement of the cam followers to measure pressure within the delivery tube at one pump phase, thereby sensing downstream occlusions, and to measure vacuum within the delivery tube at a second pump phase, thereby sensing upstream occlusions. The occlusion sensor is optical, and measures the degree of total internal reflection at the interface of the tube and the plate assembly, occlusion in the tubing.

Abstract: Methods for detecting the condition of a catheter providing access to a patient's blood vessel are disclosed in which the blood is supplied to an extracorporeal blood flow circuit. The method includes generating a pressure wave on one side of one of the access points for supplying blood to the extracorporeal blood flow circuit or returning the blood to the patient, then sensing the pressure wave on the other side of the access points. Apparatus for detecting the condition of the catheter are also provided.

Abstract: Control apparatus for an ultrasonic phacoemulsification handpiece utilizes flow rates and temperature measurements as well as power provided to a handpiece for calculating an energy balance over a time interval and in response thereto, regulating power and/or fluid flow to and from the handpiece.

Abstract: Flow in nonlinearly compliant leaky fluid circuits is controlled by alteration of control variables in fluid pathways external to the leaky circuits. In analogous practical applications, blood flow in patients undergoing total cardiopulmonary bypass is modified to limit transvascular fluid loss from the circulatory system into body tissues by altering control variables in an external fluid pathway through which venous blood from the patient passes before being oxygenated and returned under pressure to the patient's arterial system. A controller uses predetermined rules operating on control variables to achieve objectives which may include minimization of fluid leak rates and/or maintenance of euvolemic conditions in a patient's circulatory system while circulatory system flow rates are maintained at or above physiologically-established minimums.

Abstract: An apparatus for performing endoscopic surgical procedures within an internal body cavity. The apparatus includes an imaging unit for viewing the internal body cavity. In addition, the apparatus includes an intra-articular unit for providing a flow of fluid into the internal body cavity as well as for controllably withdrawing fluid from the internal body cavity. The apparatus further includes a cart which allows electrical intercommunication between the imaging unit and the intra-articular unit whereby the operation of the imaging unit and the intra-articular unit are interdependent.

Abstract: The invention relates to an apparatus for irrigating body cavities with a fluid, comprising a reservoir containing the irrigating fluid, a pumping unit which pumps the irrigating fluid from the reservoir via an instrument into the body cavity to be treated, a collector vessel receiving the irrigating fluid flowing out of the body cavity, and measuring means which detect the difference between the introduced quantity of irrigating fluid and the flowing-out quantity of irrigating fluid. The invention excels itself by the aspect that an electronic evaluation unit determines, on the basis of the output signal of the measuring means, the quantity of irrigating fluid lost and additionally the rate of variation of the lost quantity versus time.

Abstract: A method and a device for determining hemodynamic parameters during an extracorporeal hemotherapy, in which the blood arrives via the arterial branch (20) of the extracorporeal circuit (9) of the hemotherapeutic device (7), which is in fluid communication with arterial section (21) of a fistula (6), into dialyzer (10) or into a filter of the hemotherapeutic device and is recirculated via the venous branch (22) of the extracorporeal circuit (9), which is in fluid communication with venous section (23) of fistula (6). The temperature T.sub.A prevailing in the arterial branch (20) of the extracorporeal circuit (9) is measured under a changing blood flow, the temperature T.sub.V of the venous branch (22) of the extracorporeal circuit being kept constant. From the determined value pairs of the arterial temperature T.sub.A and of the extracorporeal blood flow Q.sub.B, those parameters of a predetermined function T.sub.A (Q.sub.

Abstract: An electrocardiograph controlled injection continues until a programmed amount of contrast media has been injected, rather than until a predetermined number of heart cycles has been experienced. As a result, if injections are terminated early due to a PVC in the patient's heart rhythm, the injector will continue to attempt injections for an indefinite number of subsequent heart cycles, until the programmed volume of contrast media has been injected, rather than terminating operation after a set number of injections.

Abstract: Varying flow rate and/or the fluid pressure head through a surgical instrument by selecting which of a plurality of fluid lines will supply fluid through the infusion line of the instrument. The fluid lines connect with supply ports of a common connector that has a common discharge port in fluid connection with the infusion line. The fluid lines are each in fluid connection with either a common fluid source, fluid sources at different elevations, or fluid sources at different or the same pressures. Flow control may be based on opening and closing of valves in the flow lines or operating and stopping operation of pumps or vacuum devices. A controller may determine which flow control to implement based on sensing of pressure changes in the eye or on known capacities of the pumps or vacuum devices. The sensing may be effected with a pressure transducer within the eye, but spaced from the infusion and aspiration lines of the surgical instrument.

Abstract: A irrigation/aspiration apparatus to be used in a cataractal operation comprises an irrigation fluid supply means for supplying an irrigation fluid contained in an irrigation bottle to the patient's eye, and an irrigation fluid aspirating means for aspirating, together with loosened tissues and the like, the irrigation fluid supplied into the patient's eye. The irrigation/aspiration apparatus is characterized by an irrigation flow rate varying means for varying the irrigation rate of the irrigation fluid at which the irrigation fluid supply means supplies the irrigation fluid, and an irrigation flow rate control means for controlling the irrigation flow rate varying means according to the operating condition of the irrigation fluid aspirating means to regulate the irrigation flow rate so that the variation of the pressure in the anterior chamber of the patient's eye is suppressed during the cataractal operation.

Abstract: An infusion apparatus includes a pump powered by a source of battery power and capable of operating in a plurality of infusion modes and operating in a power savings mode. The infusion apparatus further includes sensors which sense various conditions of the pump. A controller is programmed to periodically operate in a power-savings mode of operation and also selectively causes each sensor to be connected to the battery power only when the sensor is to detect a condition, thus further conserving battery power.

Abstract: A method for minimizing excess intraocular pressure during a phacoemulsification procedure in which eye tissue is fragmented and aspirated from the eye through a needle with irrigation fluid includes controlling the rate of irrigation fluid flow rate upon partial or total occlusion of the needle. For example, the method may include the steps of: introducing irrigation fluid into an eye at a selected rate; thereafter aspirating said irrigation fluid while introducing the irrigation fluid at a higher rate; during phacoemulsification and aspiration of fragmented eye tissue through the needle, introducing the irrigation fluid at the higher rate; and upon partial occlusion of the needle with fragmented eye tissue, introducing the irrigation fluid at a still higher rate.

Abstract: The invention relates to an installation for remote monitoring of a plurality of controllable equipment, in particular hospital equipment. Each of the equipment includes control means activated in response to a sequence of information. The installation also includes a portable control device. The portable control device includes a means for memorizing at least a portion of the control information relating to each equipment in association with information identifying the equipment, with the information sequence including information concerning the operating duration of the equipment. The portable control device further includes means for generating time information, and means for comparing the operating duration with elapsed time information and for transmitting an alarm signal as a function of the result of the comparison.

Abstract: A dialysis system and method for removing toxic matter from the large intestine comprises an input tube, an output tube concentric with the input tube, both of which tubes are to be inserted in the large intestine an input pressure pump connected to deliver filtrate solution from an input container to the input tube, and an output suction pump connected to the output tube to remove filtrate solution. Pressure gauges control the input and output pumps so that an input pressure level of 75 mm Hg is not exceeded, and so that the output suction pump is disabled unless the input pressure level exceeds 45 mm Hg. A filtrate solution composition comprising a vasodilator of niacin, a high molecular weight protein in the form of casein, a mineral constituents and other components is also provided.

Abstract: Surgical system for phacoemulsification providing infusion fluid apparatus and aspiration or evacuation apparatus to supplement the action of ultrasound vibrational energy applied to the surgical target area via a surgical handpiece. The supplemental apparatus for infusion and aspiration maintains a stable control volume within the anterior chamber of the human eye during a phacoemulsification procedure. Integration of the fluid pressure and flow sensors in a close proximity of less than 8 inches with the surgical handpieceand reduction of communicating fluid pressure and flow rate via fluid conduits allows fast system response time and accurate operation control.

Abstract: A phacoemulsification instrument that significantly reduces infusion fluid leakage by providing a silicone sleeve with a built in reinforcing member. Also, the sleeve has only a single infusion hole in order to provide better infusion fluid flow without causing turbulence in the eye. In addition, the present invention provides either a valve or a variable aperture aspiration tube in order to regulate the aspiration rate. Also, the present invention includes a single aspiration hole at the tip in order to amplify flow coming to the tip. To assist in cataract removal, the tip may be provided with a variety of different barrier and baffle configuration. A handpiece includes a variable capacity reservoir in the infusion line to account for surges in the aspiration line. The needle includes steps, angles and barriers to focus ultrasonic energy to aid in emulsifying nuclear tissue and to aid in pushing emulsified material in the direction of aspiration flow.

Abstract: The invention is a method of identifying whether a particular fluid collection cassette is designated to have a particular use, such as posterior surgery or anterior surgery. A reflux bulb attached to a fluid collection cassette has a material disposed on or in said reflux bulb in a predetermined location. When the reflux bulb is disposed on the fluid collection cassette, and the fluid collection cassette inserted into a housing, a sensor attached to the housing senses the existence, or non-existence of the material and sends a signal conveying the information to a main controller.

Abstract: The invention discloses methods for preserving organs in brain-dead humans or cadavers which allows additional time for the organs to remain viable such that they may be harvested for subsequent transplantation. This invention also discloses methods for preserving and/or resuscitating organs in live (nonbrain-dead) patients, allowing for additional time to stabilize the patient's condition. The methods include the steps of instrumentizing (e.g., catheterizing, cannulating, injecting, etc.) the vessels or tissues around the organ, or the organ itself sought to be preserved and/or resuscitated, the body cavity, or cavities of the body, and introducing a temperature-controlled solution to preserve and/or resuscitate the organ(s). The temperature-controlled organ preservation solution includes components such as oxygen carrying agents, antioxidants, tissue damage reversing and protecting agents, carrier vehicles, diluents, nutrients, and anti-coagulating agents.

Abstract: An aspiration and irrigation system of an ophthalmologic device for performing surgical operations on an eye of a living being, includes an irrigation unit for conducting a fluid under pressure to the eye via a first passageway, and an aspiration unit for simultaneous removal of fluid and/or tissue from the eye via a second passageway. The aspiration unit includes a two-stage pump system with a primary vacuum pump producing suction to effect a withdrawal of fluid and/or tissue from the eye through the second passageway and a secondary vacuum pump positioned downstream of the primary pump in a third passageway in communication with the second passageway, for boosting the suction pressure produced by the primary pump.

Abstract: The present invention relates to systems and methods for operating ambulatory medical devices, such as drug delivery devices. The pump includes the pump control system for activating a pumping mechanism wherein the pump control system includes a processor, a flash memory electrically interconnected to the processor for storing pump operation information, and a communications port electrically interconnected to the flash memory to permit transfer of the pump information into the flash memory from outside the pump. Communication with the pump can be through a computer system located locally or remotely with respect to the pump. The flash memory is utilized to initially program the pump electronically, or to reprogram the pump to change operation of the pump.

Abstract: An improved occlusion detector is provided in a medication infusion pump to monitor medication delivery to a patient, and to provide an early alarm in the event of medication nondelivery. The detector comprises a force sensor and related control circuit for reading and comparing the pressure applied to the medication at the time of pump operation to administer a dose to the patient, with the same pressure at a later point in time preceding the next dose. If the difference between the pressure readings is less than a predetermined value, an occlusion of the medication delivery line is indicated and an alarm is activated.

Abstract: A peritoneal dialysis system is illustrated of the continuous flow type which includes a reverse osmosis unit which prepares sterilized and filtered water for mixing with a sterilized dialysate in a dialysis production unit. The process includes proportioning water, dialysis concentrate, and dextrose to provide a dialysis fluid which is then heated and sterilized. The fluid may be accumulated in a reservoir which accumulates a desired amount of dialysis fluid as measured by a load cell which measures the weight of the fluid. The dialysis process may be used with a single or double catheter. A desired amount of fluid is delivered to the peritoneal cavity as measured by the load cell, and a desired amount of fluid is drained from the cavity as measured by a load cell into a drain reservoir so that a desired amount of peritoneal dialysis fluid is maintained in the cavity during dialysis.

Abstract: An infusion apparatus having a pump powered by a source of battery power and a controller that performs a plurality of processing tasks related to the pumping of liquid through a conduit. The controller is operable in a normal mode of operation utilizing a first rate of power consumption from the source of battery power. The infusion apparatus includes control means for causing the controller to operate in a first power-saving mode of operation utilizing a second rate of power consumption, the second rate of power consumption being lower than the first rate of power consumption, and the control means causes the controller to operate in a second power-saving mode of operation utilizing a third rate of power consumption, the third rate of power consumption being lower than the first rate of power consumption.

Abstract: A dialysis system and method for removing toxic matter from the large intestine comprises an input tube, an output tube concentric with the input tube, both of which tubes are to be inserted in the large intestine an input pressure pump connected to deliver filtrate solution from an input container to the input tube, and an output suction pump connected to the output tube to remove filtrate solution. Pressure gauges control the input and output pumps so that an input pressure level of 75 mm Hg is not exceeded, and so that the output suction pump is disabled unless the input pressure level exceeds 45 mm Hg. A filtrate solution composition comprising a vasodilator of niacin, a high molecular weight protein in the form of casein, a mineral constituents and other components is also provided.

Abstract: A system which provides information necessary to diagnose a failure or malfunction of an oxygenator. The system provides information to differentiate oxygenator failure from other causes of hypoxemia (inadequate blood oxygen concentration). Such as malfunction of the ventilating circuit, or components of the ventilating circuit. This is accomplished by analyzing the oxygen concentration of the ventilating gas entering the oxygenator, the flow of the ventilating gas entering the oxygenator, and also the pressure in the ventilating gas circuit or the pressure of gas within the oxygenator. As a result the invention provides information to diagnose ventilating gas flow obstruction or a gas leak from an oxygenator housing.

Abstract: The irrigation circuit of this apparatus comprises a second pressure sensor CP2 forming a flowmeter with a first CP1, as well as a pressure sensor CPA located downstream.The apparatus also comprises a processing and control unit UCCG which establishes the calculated value of internal pressure within the cavity PI using the pressure variations furnished by pressure sensors CP1, CP2 during a procedure in relation to the values of the pressure differences during operation outside the cavity, which are stored for each resectoscope RT1. . . RTi . . . RTn during an initial calibration phase so that the absorption flow rate can be controlled.This invention is of interest to manufacturers of surgical instruments.

Abstract: An infusion apparatus includes a roller assembly adapted to exert pressure on opposed sides of an IV bag to forcibly remove the fluid contents therefrom in an even and controllable manner. A sensing element mounted to the roller assembly senses the pressure exerted during the infusion operation and generates a signal to a control assembly which automatically adjusts the movement of the roller assembly in response to the pressure sensed. If the pressure sensed exceeds a predetermined level, the control assembly will activate a drive assembly to return the roller assembly to a neutral position.

Abstract: An apparatus essentially consisting of an aspiration conduit, a pump, and a pressure transducer and logic console which senses vacuum level fluctuations in the aspiration conduit. The aspiration conduit is connected to a surgical cavity. The pump creates a vacuum in the pre-pump aspiration conduit and transports the fluid and/or tissue material from the surgical cavity, through the aspiration conduit and into a collection container. The logic console responds to a predetermined rate of decrease in vacuum in the pre-pump aspiration conduit and causes an electric signal to be sent to 1) the pump, which upon receiving such signal, reverses its action and/or: 2) an electromechanical valve located along the aspiration conduit, which upon receiving such signal acts to occlude the aspiration conduit and terminate the removal of tissue or fluid from the surgical site. The reversal of rotation prevents the occurrence of a fluid surge which would result in the collapse of the surgical cavity.

Abstract: A liquid level sensing and monitoring system for a medical fluid infusion system has an IV spike with a pressure sensor which contacts fluid in an infusion container such as an IV bag or bottle. When an adequate amount of fluid is in the container, the resulting pressure on the sensor is at a relatively high level; however, when the fluid reservoir is nearly depleted, the pressure on the sensor falls to a low level, thereby activating the sensor and associated control circuitry which operates an alarm or warning indicator. In lieu of the pressure sensor, the device may use a resistive or capacitive sensor. When the liquid level falls below the electrical sensor, its state changes, and the alarm circuitry is activated.

Abstract: A device for the irrigation and suction drainage of body cavities, especially in surgical laparoscopy, hysteroscopy, uroscopy, or arthroscopy. The device comprises two conventional pumps, each being equipped with a pressure sensor and being preferably designed as rotary tube pumps. The irrigation pump and the suction drainage pump are connected with each other by way of a control line, and they operate in a master-slave mode. Operation is very simple, in that only the irrigation pump needs to be adjusted and operated by the operator. Control of the suction drainage pump takes place automatically based on the measured values of both pressure sensors in the irrigation and suction drainage conduits and the set r.p.m.'s of the irrigation pump. The primary advantage of the device resides in that the suction drainage pump takes care automatically of uniform pressure and flow relationships at the site of the surgery independently of the adjustment of the irrigation pump.

Abstract: The present invention concerns a pump provided with a control module and an attachable fluid reservoir cassette. The control module includes a pumping mechanism for pumping fluid from the fluid reservoir to the patient. The cassette is provided with appropriate indicia to identify differences between a plurality of cassettes. The control module further includes cassette indicia identification structure for identifying indicia on the cassette. One type of cassette identification system includes a projection extending from the cassette and structure associated with the control module which engages the projection. Another type of cassette identification system includes a light reflecting system which utilizes light from the control module and reflected off the cassette. Still other types of cassette identification systems utilize other non-contact switches or sensors to sense indicia on the cassette to identify the cassette from a plurality of cassettes.

Abstract: The present invention concerns a pump provided with a control module and an attachable fluid reservoir cassette. The control module includes a pumping mechanism for pumping fluid from the fluid reservoir to the patient. The cassette is provided with appropriate indicia to identify differences between a plurality of cassettes. The control module further includes cassette indicia identification structure for identifying indicia on the cassette. One type of cassette identification system includes a projection extending from the cassette and structure associated with the control module which engages the projection. Another type of cassette identification system includes a light reflecting system which utilizes light from the control module and reflected off the cassette. Still other types of cassette identification systems utilize other non-contact switches or sensors to sense indicia on the cassette to identify the cassette from a plurality of cassettes.

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 pressure 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 (10) and method for surgical decompression and irrigation/lavage of a patient comprising a tube (12) having a distal end (14) which is inserted into the intestine and a proximal end (16) which is located outside the patient. The tube (12) has a wall which surrounds a plurality of longitudinally extending lumens. A suction lumen (22) is connected to a suction means located exteriorly in relation to the patient. There are one or more pores capable of delivering irrigation fluid and for syphoning the contents of the patient's intestine. An irrigation lumen (24) is connected to irrigation means (32) located exteriorly in relation to the patient. There are one or more openings extending from the suction lumen (22) to the irrigation lumen (24) for ducting irrigation fluid or gastrointestinal content and for avoiding plugging of the pores by particulate matter or by a stomach lining when the stomach is aspirated.

Abstract: An open loop system for delivering fluid during hysteroscopic surgery. The system includes first and second fluid conduits in fluid communication with the uterine cavity of a patient. First and second measuring devices are provided for measuring the amount of fluid flowing into and out of the uterus. The measuring devices produce electronic signals which are communicated to a controller which uses them to calculate a value reflecting the difference in in-flow and out-flow. This difference is then compared with a preset value; if the preset value is exceeded, the surgeon knows the patient is absorbing too much fluid, and the procedure may be terminated.

Abstract: A medical method comprises the steps of attaching a sensing device to a limb of a patient, automatically operating the sensing device to monitor a circumference of the limb, automatically comparing a measured circumference with a reference value, and automatically generating an alarm signal upon detecting that the measured circumference differs from the reference value by more than a predetermined magnitude. In one application of the method, an intravenous catheter is inserted into a blood vessel in the limb, and a fluid is fed into the blood vessel via the catheter. The limb is covered upon insertion of the catheter and attachment of the sensing device, thereby preventing direct visual observation of the limb during performance of a surgical operation on the patient. The circumference measurements and automatic comparisons are performed periodically.

Abstract: The disclosure is of a suction catheter having a valve body including a vertical plunger in a vertical bore and two horizontal tubes, one for connection to a source of suction and one for connection to a patient. In one position of the plunger, the two tubes are aligned with a path through the plunger to provide suction to the patient. In another position of the plunger, the tube connected to the suction is led to the atmosphere whereby suction is completely removed from the patient.

Abstract: A surge suppresser which has a collapsible flexible wall that accumulates the aspiration fluid of an interocular surgical system. The surge suppresser has an inlet port and an outlet port that are connected to an aspiration line downstream from a surgical tip. The aspiration line is connected to a vacuum device which draws fluid from the tip. When an occlusion in the aspiration line occurs, the decrease in pressure caused by the vacuum device will cause the flexible wall to collapse and close the inlet and outlet ports of the surge suppresser. When the occlusion breaks, the inlet port initially opens and the outlet port remains closed so that the flexible wall is expanded by the flow of fluid from the surgical tip. The closed outlet port prevents a surge of fluid from the eye. Additionally, the ports are arranged in a parallel relationship to reduce the momentum of the fluid into the suppresser and further limit the surge of fluid from the eye.

Abstract: Peritoneal dialysis systems and methods move liquid using a pump chamber that is operated in response to pneumatic pressure variations applied by a pump actuator. The systems and methods periodically measure air pressures in the actuator and an associated reference air chamber and derive from these a measurement of liquid volume moved through the pump chamber. The systems and methods minimize derivation errors by compensating for temperature differences among the pump chamber; the pump actuator; and the reference chamber.

Abstract: A volume sensor is described for automating an extracorporeal system used for the recovery and concentration of salvaged blood. The system includes a disposable plastic reservoir in which blood is collected from the surgical site and stored for processing. Volume is sensed in one embodiment by a strain gage device which is sensitive to vertical forces. In another embodiment volume is sensed by measuring the transit time of an ultrasonic pulse-echo signal generated by piezoelectric transducer.

Abstract: An irrigation system contains a safety relief valve and a safety relief valve control valve. The safety relief valve control valve acts to modulate the operation of the safety relief valve when there is flow from an outflow port. By this mechanism high flow rates are accommodated without causing premature activation of the safety relief valve.

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 medical pump drive for automatically displaying not only the flow rate of circulating blood but also blood flow rate per surface area of the body of a patient in a medical treatment such as extracorporeal circulation includes at least a pump driving circuit, an ultrasonic transceiver and ultrasonic oscillator for measuring flow rate of the blood conveyed by a pump, a CPU, to which values of height and weight of a patient are entered, for calculating the body surface area of the patient as well as the blood flow rate per body surface area of the patient based upon the blood flow rate and body surface area obtained, an LCD for displaying the calculated blood flow rate per body surface area, and an LED for displaying the blood flow rate obtained.

Abstract: An irrigation system including a pump that regulates the supply of fluid to an endoscopic surgical site, and a tubing set for supplying the fluid. The tubing set comprises an inflow line for supplying fluid to the surgical site, and an outflow line for draining fluid from the surgical site. At least one of the inflow and outflow lines includes an expandable compliant tubing segment that expands to accommodate changes in the rate of fluid flow through the surgical site to reduce variations in fluid pressure in the surgical site. The fluid volume within the compliant tubing segment increases in response to increasing fluid pressure within the compliant tubing segment. The system is particularly designed for use in small joint arthroscopy (e.g., of the wrist) where the fluid volume in the surgical site is relatively small.

Abstract: A check valve manifold assembly contains multiple inlet and outlet ports extending through a housing into a fluid passageway. The fluid passageway interconnects the various ports, and the housing further contains multiple check valves, one such valve being associated with each of the ports. When used with an active perfusion pump, the manifold system permits easy and proper perfusion of the patient at high pressures.

Abstract: A data transfer system is provided for communication with an infusion pump of the type used for programmable delivery of medication such as insulin to a patient. The data transfer system includes a communication station having a shaped pocket formed therein for seated reception of the infusion pump. Optical communication members including light emitting and detecting devices mounted on the pump and station are aligned for two-way data transmission when the pump is seated within the station pocket. The communication station can be used directly to monitor data received from the pump, and to transmit reprogrammed data to the pump, as desired. Alternately, the communication station can provide a data relay link to a remote site such as to a computer via a computer data cable, or a modem.