Abstract: A microsurgical irrigation/aspiration system is provided, including a controller having a pump roller head, actuators for occluding tubing, a suction sensor, and apparatus for mounting a pump cassette. The system cassette is suitable for mounting on the controller and has an opening with a pump tubing segment passing along an arcuate wall of the opening. When the cassette is mounted on the console, the roller head is engaged in the cassette opening and compresses the pump tubing segment against the arcuate wall. An infusion line passes through the cassette and is occludable by one of the actuators, and a vent line connected to the pump tubing segment is occludable by a second actuator. A suction sensing port on the cassette couples with the suction sensor in the controller.

Abstract: A therapeutic suction device includes an operating vacuum chamber connected to a motor operated pump to create a vacuum pressure therein and a pressure controlling means to maintain a predetermined pressure in the vacuum chamber. The vacuum pressure in the operating vacuum chamber can be pre-arranged so as to provide a suction force by a pressure difference even when there is a shortage of electricity.

Abstract: An improved lipectomy device, or cannula, is disclosed having inner and outer tubes. The outer tube has an elongated aspiration aperture, and the inner tube has a spiral slot. A mechanism inside the handle of the device causes the inner tube to rotate, creating a traveling hole effect along the aspiration aperture. This obviates the necessity of the surgeon repeatedly pushing the cannula in and out. A valve system is also disclosed which allows the surgeon to maintain negative pressure in the vacuum line leading to the cannula while still allowing the cannula itself to be vented to ambient pressures.

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 surgical aspirator cannula including an elongated body having a distal end, a distal end port, a proximal end, a proximal end port and an aspirator conduit passing longitudinally therethrough. A cannula is removably secured to the distal end and when secured its cannula tip opening communicates through the cannula passageway with the distal end port. The proximal end of the body member is connected to a vacuum pump. A ball valve assembly is mounted in the body member in the aspiration conduit, and is operated by a hand-operated lever, knob or button supported on the body member. When the lever is then operated the valve assembly is selectively opened or closed to selectively communicate the source of vacuum with the distal end port and thus the cannula. The cannula has its proximal end fitted into a ferrule which fits into an adaptor that is screwed into the distal end portion of the body member.

Abstract: The aspirator system of this invention is directed to an economical regulator assembly which can provide a substantially uniform vacuum without the need for periodic adjustment. The vacuum of the system can be easily and accurately adjusted, thereby accommodating changes in system pressure demands. The system is not prone to vacuum leakage or undesired vacuum fluctuations.

Abstract: A pistol-shaped frame (26) houses a fluid distribution assembly (58), including a plunger (46) operated by a trigger (30) for discharging fluid from a reservoir (60) through an outlet check valve (68). On return of the spring-loaded trigger (30), an inlet check valve (80) allows fluid to be drawn into the reservoir (60). A thumb-operated valve assembly (96) provides a fluid passage between an output (12) of the device and the outlet check valve (68) in one position, and in another position provides a vacuum passage between a vacuum inlet port (104) and the output (12). Trigger graduations (136 ) provide a visual indication of measured amounts of fluid dispensed by the device (10).

Abstract: An improved lipectomy device, or cannula, is disclosed having inner and outer tubes. The outer tube has an elongated aspiration aperture, and the inner tube has a spiral slot. A mechanism inside the handle of the device causes the inner tube to rotate, creating a traveling hole effect along the aspiration aperture. This obviates the necessity of the surgeon repeatedly pushing the cannula in and out. A valve system is also disclosed which allows the surgeon to maintain negative pressure in the vacuum line leading to the cannula while still allowing the cannula itself to be vented to ambient pressures.

Abstract: The present invention is directed to improved methods and apparatus for the collection of blood, which are particularly useful for autotransfusion purposes. The apparatus includes a conventional blood transfer bag which is in turn placed in fluid communication with an air-blood separator to form a collection system. This system is particularly adaptable for use in the surgical setting in that it can operate at high vacuum while minimizing hemolysis. This is accomplished by early separation of air from the blood as the blood is collected.The air-blood separator and the interior of the blood bag are placed in communication with a vacuum source. As a result, there is a pressure equalizing feature inherent within the device. This allows the blood to continue to flow through the device into the blood bag without extending or opening the blood bag. As a result, there is minimal air-blood interface as the blood enters the blood bag.

Abstract: The present invention is directed to improved methods and apparatus for the collection of blood, which are particularly useful for autotransfusion purposes. The apparatus includes an upper reservoir wherein the collected blood enters the device. A lower container is placed in fluid communication with the upper reservoir. Disposed within the interior of the container is a conventional blood bag which is in turn placed in fluid communication with the upper reservoir. The upper reservoir has two external connections. The first connection is for receiving blood from the patient. The second external connection places the upper reservoir in communication with a source of vacuum. In one embodiment of the present invention a filtering structure is disposed within the upper reservoir and is connected directly to the inlet connection from the patient.

Abstract: The valve is positioned in the left ventricle drain line and includes a check valve which permits flow only away from the heart. A vent valve is located downstream of the check valve to prevent buildup of pressure. In addition, the valve includes an inwardly directed umbrella valve to limit left ventricle drain line vacuum intensity applied to the heart.

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 collection system particularly suitable for drawing fluids from a patient area and storing the fluids for later use or disposal, which is operable in any orientation of the device, thereby providing a field operable system which may be transported in battlefield conditions. The portable suction system consists of a cylindrical evacuating chamber with a top sealing cap. A suction port on the sealing cap is connected to the fluid collection bag, which consists of a laminar flexible plastic bag having an air permeable, liquid impermeable patch or portion through which air may pass for purposes of providing a vacuum suction, yet the collected fluids will remain in the bag. The suction power is provided by a vacuum pump which is electronically regulated by periodically energizing and de-energizing the pump to conserve power supply energy.

Abstract: A fluid T-coupling comprising a through fluid flow path, and an intersecting vent path, wherein the vent path is integrally molded within the filtered bayonet connector to be used with an aspirator to control the level of vacuum communicated to an irrigation/aspiration handpiece during eye surgery.

Abstract: A surgical suction cassette for use with a microsurgical apparatus having a surgical handpiece connected by tubing with a control cabinet contains a tank to receive aspirated material from the microsurgical site, fluid connections for the tubes providing suction, pressure and irrigation fluid to the handpiece, fluid connections for connecting sources of pressure, vacuum and vent within the cabinet, fluid connection for an external source of irrigation fluid, and internal tubing providing connections between the connections to the handpiece and the connections to the cabinet. Solenoid actuated occluders in the cabinet compress the tubing in the cassette to turn the various fluid streams on and off. The cassette is provided with a drain for automatically removing the contents without changing the cassette. A latch hook, centrally located between the fluid connections to the cabinet holds the cassette in the cabinet when in use.

Abstract: A multi-component meconium aspirator, adapter and endotracheal tube are manipulated, by one-handed use, to keep them assembled and to control suction level, during meconium removal from an infant.

Abstract: The valve is positioned in the left ventricle drain line and includes a check valve which permits flow only away from the heart and downstream of the check valve includes a vent valve which prevents buildup of pressure. In addition, the valve includes a vacuum orifice to limit left ventricle drain line vacuum intensity applied to the heart.

Abstract: A male fluid control member for controlling aspiration flow is insertable in a standard female receptacle having an interior cylindrical recess including a vent line leading to the recess. The male member includes an open end intruding into the recess in the female receptacle and filled by a protruding resilient gasket having a central orifice. The end recess is in communication with an interior chamber that extends along the aspiration fluid flow path, but is sealed therefrom by a hydrophobic membrane of substantial cross-sectional area. In operating position the orifice in the gasket in the male member is aligned with the vent line and the gasket and membrane seal the conduit thus formed from external sources of contamination. The opening in the gasket diverges in the direction toward the membrane which, together with the interior chamber, has a substantial cross-section.

Abstract: A regulator is provided for controlling the degree of suction within a collection chamber in a drainage device. The regulator includes a means for measuring the degree of negativity within the chamber and a feedback passageway leading from the measuring means to the suction source. When the measuring means detects a degree of negativity which is equal to or greater than a predetermined value in relation to the available suction the feedback passageway is opened to atmosphere and when the degree of negativity becomes less than the predetermined value the feedback passageway is closed so as to impose the full suction of the suction source upon the chamber.

Abstract: A fluid drainage system includes a suction chamber and a collection chamber. The suction chamber includes a suction regulator comprised of first and second chambers separated by a divider. An opening in the divider has a biased closing member associated therewith for opening or closing the opening according to the pressure differential between the chambers. A dash pot is connected to the closing member for damping the force on the closing member. The drainage system further includes devices for measuring the patient airflow, patient negativity and imposed suction. Those devices consist of diaphragms having dials connected thereto such that movement of the diaphragm results in movement of the dial and thereby indicating a change in one of the above noted variables. As an alternative, the drainage system includes a venturi meter for measuring airflow. Finally, the system contains an anti-spill device that prevents the spilling of fluids from the collection chamber to other chambers in the device.

Abstract: A linear suction control system 10 includes a linear solenoid valve 11 which exhibits a flow through rate having a known proportional relationship with the current through the solenoid 30. Regulated fluid pressure 12 is fed through the linear solenoid valve 11 to a venturi-type pressure vacuum converter 17. The resulting vacuum is proportional to the flow rate through the valve 11 and thus to the current through the solenoid 30. A transducer 16 samples the vacuum output and produces a signal fed to a differential amplifier 17. The signal is compared in negative feedback fashion with a variable input voltage set by a potentiometer 18 or other variable voltage source, so that the transducer signal tracks the voltage source signal. The voltage source can comprise a potentiometer 18 actuated by a foot switch 19 or the like, so that angular position of the foot switch 19 relates directly and predictably to the vacuum output of the converter 13.

Abstract: An intubation suction device having first and second elongated tubular sections and a centrally located, uniquely configured handle is disclosed. The first section has an in-line port which has two functions. First, it acts as a suction valve to control suction. Second, its permits the easy introduction of a stylet through the device to an associated endotracheal tube. This latter feature enables the endotracheal tube to be easily inserted into the trachea region of a new born baby. By use of such device, expedited suction of material, such as meconium, from the oral, nasal, gastric and trachea regions of a newborn baby can be achieved.

Abstract: A ventilating and aspirating assembly comprising an aspirating catheter tube internally disposed within and coextensive with a surrounding flexible collapsible sterility preserving film envelope, a connector by which ventilating air is involuntarily delivered to and exhausted from the lungs of a medical patient, said connector comprising structure which accommodates the manual insertion of the catheter tube into and manual removal from the trachea/bronchi patient through the connector. This facilitates aspiration of undesired respiratory fluids.

Abstract: A lavage/suction tip comprising an elongated barrel with a first pliable conical shield extending outwardly from the distal tip of the barrel and a second substantially rigid conical shield which is slidable upon the barrel. The lavage/suction tip is utilized to provide irrigating fluid to a surgical site while providing suction to remove fluids and debris away from the surgical site. The first shield helps to eliminate splashback of the fluid. The second shield may be positioned to surround the first shield to provide firm support about the first shield, yet with a flexible, pliable tip perimeter. Alternatively, the second shield may be secured on the tip spaced away from the first shield so that the pliable first shield is used alone and may be easily, manually formed to more closely match the tip of the first shield to the working area or surface of the surgical site.

Abstract: The invention relates to a surgical instrument especially for performing neurosurgical operations, having a flexible suction tube to be connected to a vacuum source, the suction tube being provided with a finger plate having a hole communicating with the inner space of the suction tube. The suction tube is provided with an electric connector which can be connected to a high-frequency power source and the portion of said suction tube reaching the locality of the operative field--with the exception of the tube end functioning as a coagulating end--being provided on its outer surface with an electrically insulating, flexible plastic coating.The basic point of the invention is that the suction tube (2) is formed by a silver pipe with a coat (4) made of a synthetic thermoplastic material of the polyamide type.

Abstract: The fluid infusion device includes a primary and an auxiliary fluid pump capable of providing a substantially continuous flow of a fluid, such as air. A pressure regulator driven by a reversible electric motor regulates the air pressure and the flow of pressurized air through an disposable air delivery unit, consisting of a millipore, bacterial static filter and a tube removably connected to an air outlet is controlled by a normally closed, solenoid-operated infusion valve. Separate pressure transducers detect the pump output pressure, the regulator outlet or preset pressure, and the infusion pressure downstream of the infusion valve when it is open.

Abstract: A multiple suctioning system, particularly for use in endoscopic procedures or the like, which is provided with a suction source, a Y-shaped connector which is provided with a rotatable stopcock and a plug-like stopper, at least three segments of pliable tubing, and a suction catheter which comprises an elongated handle, a deformable tip, means for preventing the tip from plugging, means for anchoring the catheter in a convenient location, bright-colored vinyl plastic tubing to connect the catheter to a suction source, means for attaching the tubing to the catheter, and means for controlling the flow of suction forces through the catheter.

Abstract: A method and apparatus for aspirating secreted fluids from a wound is disclosed which involves the placement of a drain into a wound via the tissue adjacent the wound. After the wound is closed, a secretion aspiration and collection device, which is connected to the drain via a tube, is placed into operation. The device is designed to have a suction effect controlled between a minimum value and a maximum value according to the quantity of secreted fluid to be aspirated. This is achieved by one or more sensors which control a tube pump. When a second sensor is used, the pump will not be shut off by a passing air bubble in the fluid. A sleeve may also be provided to facilitate introduction of the drain into the wound. Additionally, a needle may be detachably connected to the sleeve to aid the insertion of the sleeve.

Abstract: A system for electronically monitoring and controlling the drainage of fluids from a body cavity, including transducers for measuring suction, suction air flow, patient air flow, patient negativity and the like, and displays for rendering measured values in legible form. Various valves for regulating pressure and flow rates are electronically controlled according to desired values and direct measurements of the respective parameters.

Abstract: The valve is positioned in the left ventricle drain line and includes a check valve which permits flow only away from the heart and downstream of the check valve includes a vent valve which prevents buildup of pressure. In addition, the valve includes a manually adjustable vacuum control orifice whereby the surgeon can control the left ventricle drain line vacuum intensity applied to the heart.

Abstract: The replaceable cassette is integrally formed with a small primary container for fast response time when aspirating, and an integrally formed, larger secondary container into which the contents of the primary container are periodically flushed. During aspiration, the secondary container is sealed from the primary container and, therefore, has no adverse effect on aspiration response time. The primary container is located above the secondary container and the two containers are connected by a standpipe through which substances are flushed by the force of gravity in emptying the contents of the primary container into the secondary container. Although the cassette will operate with microsurgical consoles having two separate vacuum sources, only one vacuum source is required.

Abstract: The application discloses an operation aspirator with which, without provoking contamination of the aspirator opening, fine-metering of the vacuum that is available at the aspirator opening is possible and actuation of the valve apparatus closing off the suctioning line is simultaneously made easier.

Abstract: A device for the aspiration of an air pocket surrounding a collapsed lung. The device includes a needle to be inserted into the cavity surrounding the collapsed lung, through the ribs of the patient. The needle is connected to a suction pump by means of a hose. A float-type flow-meter is provided to measure the air flow rate through the hose and the suction pump and to transmit an electrical signal which is indicative of the flow rate to an electronic controller which calculates and displays the total volume of the air that has flowed through the sensor. A vent line is provided between the suction pump and the flow-meter to prevent sudden increases in flow rates through the needle, and a three-way valve is provided to control flow through the vent line.

Abstract: The present invention discloses an improved suction device and a method of making the same. The improved device comprises a valve means for one time use, particularly in health care field. The valve device is made from two parts which are pushed into one another while bending at least one resilient lip into a shunt conduit or into abutment over the shunt conduit opening to the channel, so that the lip is limited in its movement by another part of the device.

Abstract: A continuous vacuum drainage system for wound drainage. A base unit has apparatus responsive to releasable attachment thereto of a drain reservoir for evacuating the reservoir to a subatmospheric pressure in a predetermined range. The drain reservoir is continuously operable before, during and after release from the base unit for uninterrupted suction draining of a wound.

Abstract: A ventilating and aspirating assembly comprising an aspirating catheter tube internally disposed within and coextensive with a surrounding flexible collapsible sterility preserving film envelope, a connector by which ventilating air is involuntarily delivered to and exhausted from the lungs of a medical patient, said connector comprising structure which accommodates the manual insertion of the catheter tube into and manual removal from the trachea/bronchi patient through the connector. This facilitates aspiration of undesired respiratory fluids.

Abstract: A medical instrument for removing fat from inside a human body is provided wherein first and second projections, each adapted to be connected to a suction probe or a suction tube, are located at one end of a hollow body.

Abstract: Fluid coupling devices are disclosed for use in receptacles such as receptacles on surgical aspiration equipment for selectively connecting a fluid conduit in the receptacle with a flow passage formed through a coupling device. The coupling devices in accordance with the invention comprise a spindle member which is non-rotatably held in the receptacle and a body member rotatably mounted on the spindle member for movement between an open position in which communication is established between the flow conduit in the receptacle and the flow passage in the coupling device, and a closed position disconnecting the conduit from the flow passage. The body member has a cam insert member with a through bore for connecting the flow conduit with the flow passage.

Abstract: Anticoagulant is added to blood being aspirated through a hand-held wand having a venturi throat. The anticoagulant flows into the wand from a generally closed anticoagulant reservoir higher than the wand as replacement air flows into the anticoagulant air reservoir. This air inflow is controlled by a regulator fixed on the wand and in accordance with the amount of aspirated blood flowing in through the venturi throat.

Abstract: A surgical instrument for use in suction lipolysis consists of a long, narrow tube having a pointed or tapered closed end, for insertion into the body, and being open at the other end for connection to a source of vacuum. The tube has a side opening adjacent to the closed end for entry of fatty material during use. A passageway is provided, either as a separate passage inside the tube or a separate tube inside or outside the main tube, with an end opening inside the closed end of the main tube beyond the side opening. A handle surrounds and supports the main tube and passageway and includes a manually operated valve for venting the other end of the passageway or separate tube to allow air to enter the closed end portion of the main tube during use for clearing obstruction therein.

Abstract: A suction control device for an aspirator system includes a generally T-shaped body having a main lumen and a passage which extends outwardly from the lumen to the exterior of the body through a vent or chimney portion of the body, and a resiliently deformable closure cap having one or more apertures therethrough which is received on the end of the chimney portion. The chimney portion is preferably formed with a flared terminal end, and the cap is resiliently depressible to a closed position wherein the apertured portion thereof is urged against the inner surface of the flared chimney portion end to obstruct the apertures in the cap and thereby close off the chimney portion. When the device is in the open position thereof, suction communication in the main lumen is interrupted by a venting effect through the chimney portion; and when the device is in its closed position, suction or negative pressure may be transmitted through the main lumen.

Abstract: A suction irrigator, particularly for surgical use, is made as two units of plastics material. One unit is formed by a handle having first and second parallel bores which are coupled respectively to a suction source and a source of irrigating fluid. The other unit comprises a valve assembly the housing of which is formed by injection moulding. The valve assembly has two inlet conduits which are inserted within respective bores in the handle, and an outlet conduit which can be connected to one or the other of the inlet conduits by displacing a valve member. The bores extend along tubular formations in the handle which are linked along most of their length by a land but which are separated by a slit close to the valve. On the handle there is a lip positioned to engage a resilient catch on the valve member and thereby limit its displacement.

Abstract: A selective tracheal bronchial catheter is provided with a double bend at the distal end and means for twisting the catheter around its longitudinal axis at its proximal end. Thus, the surgeon can selectively cause the tip of the catheter to enter the left main bronchus and upper lobar bronchus without fluoroscopy. Slight withdrawal and 15.degree. twist guides the tip into the left lower lobar bronchus. Slight withdrawal and 180.degree. twist guides the tip into the right main bronchus. Markings on the catheter indicate the degree of twist of the double bend and the distance of insertion. A concentric irrigation tubule, of different material, irrigates and dislodges phlegm, well in advance of the suction tip of the catheter, and self cleans the catheter tip opening.

Abstract: An endotracheal complex for insertion into the trachea of a patient, and wherein the trachea branches through the carina trachea distally into two bronchi, includes a tube which has a distal blunt and atraumatically shaped tip so as to restrain passage of the tip beyond the carina tracheae into the bronchi and to serve as an internal palpator to identify an anatomical reference point, and an inflatable cuff near the tip for preventing any air or air component other than oxygen emanating from the source of oxygen to pass to the bronchi. A removable introducer is disposed in the tube and has a bevelled end portion to facilitate insertion of the tube through the larynx into the trachea. After the endotracheal tube is inserted into the trachea of a patient, the bevelled end portion is removed by pulling on the introducer tube or stylet. The bevelled end portion collapses off the blunt end of the endotracheal tube and can be pulled through the endotracheal tube to be removed and discarded.

Abstract: A method is disclosed in which the suctioning of materials from a surgical zone, such as the human eye, is automatically controlled linearly by means of a pressure transducer continuously sensing the vacuum level of a debris receptacle (for collecting suctioned materials from the surgical zone) when material is being suctioned from the zone. The vacuum level in the debris receptacle is linearly varied when the vacuum level in the receptacle is either raised or lowered depending on the suctioning requirements from the surgical zone and whether or not the vacuum level in the receptacle is greater or lower than a previously determined and desirable vacuum level. The vacuum level of the receptacle may, in part, be controlled and varied, by means of a foot pedal operated by the surgeon.

Abstract: An adjustable, disposable suction device that is particularly adapted for medical use. The device is used for removing excess blood or body fluids from an open incision during surgery and is constructed so that it can drain the fluids from a point source or from a larger general area. In the latter case the device can be adjusted to control how much fluid is removed in a given period of time. The device is essentially comprised of a handle, a rigid outer tube formed with an oblique bend and a coacting flexible inner tube. The outer tube is connected at one end to the handle and has a plurality of longitudinally spaced radial apertures adjacent its free end. The flexible inner tube is positioned with a sliding fit in the rigid tube. The inner tube is open at its outer or free end but is otherwise imperforate. With this arrangement, the inner tube can be moved longitudinally within the outer tube to block all of the outer tube apertures or selectively open some or all of them.

Abstract: A fast response vacuum aspiration collection system includes a pair of sealed collection containers, one container having a significantly smaller volume. The larger container is connected to a fixed vacuum source, the smaller container is connected to a controlled, variable vacuum source, and the containers are connected together by an exchange line passing through a normally closed first pinch valve. A surgical probe line is connected to the exchange line, and extends through a normally closed second pinch valve to an aspirating surgical instrument. The controlled vacuum applied to the smaller container is conducted through the exchange line and the surgical line to the surgical instrument, with the small volume of the small container quickly assuming the vacuum level applied to that container.

Abstract: A surgical aspirator adaptable for body cavity or passageway use includes a handle having a vacuum passage extending longitudinally therethrough and a valve bore extending perpendicularly therethrough to receive a poppet in sealing fashion. The poppet includes sealing ribs protruding radially therefrom and extending longitudinally therealong to form a seal in the bore in any rotational position. The poppet also includes a radio-opaque pin which extends through the open port thereof. An aspirator tube is received in a bore in the handle, and is retained therein by the frictional engagement of an elongated hole in the aspirator tube which includes edges deformed radially outwardly therefrom to engage the bore. The distal end of the aspirator tube includes crossed slots extending therethrough and through adjacent side wall portions to prevent clogging thereof.

Abstract: A medical aspirator including an automatic valve means to reverse the flow of air upon stoppage of the suction system whereby the stoppage may be dislodged and the normal suction function of the aspirator is reinstituted. The aspirator includes a spring loaded suction responsive trigger means to rotate the valve means.

Abstract: A flexible, compressible reservoir draws a substantially constant vacuum to permit uniform removal of fluid from a surgical incision through a wound drain catheter. The reservoir includes a compression spring interposed between a pair of congruent articulated plates. The spring provides biasing force to expand the reservoir and create a vacuum therein. Each of the articulated plates has a central member hinged on opposite sides to wing members. As the reservoir expands, the wing members pivot relative to the central members to decrease the effective area to which the spring force is applied. Such decrease in the effective area permits the spring force per unit of area to remain more nearly constant, and thus, reduces changes in reservoir vacuum.