Abstract: An anti-free-flow mechanism includes an occluder mechanism which is disposed along a segment of tubing and a mounting structure. The occluder mechanism is normally in a biased closed position, but may be moved into an open position by placement in the mounting structure. However, unless force is applied to keep the occluder mechanism in the mounting structure, the occluder will move relative to the mounting structure and return to the first, closed position.

Abstract: A pressure sensor and method of use provides for the detection of a sudden increase or decrease of pressure within tubing during the administration of solutions to a patient. Detection of an occlusion, partial or other significant pressure change in the tubing is accomplished by measuring the compression and/or expansion of the tubing. Transfer of the change in force within the tubing is communicated from the tubing to a sensor by a transfer rod which as a membrane attached thereto to provide a seal thereabout.

Abstract: Air bubbles may be characterized by an air bubble detector by choosing an optimum set of frequencies and then comparing a return signal from a sensor receiving those frequencies against an internal reference. The number of pulses that exceed the internal reference represents a width and may be counted. The width, as counted, may be correlated to bubble characteristics including volume.

Abstract: In an infusion pump operable to deliver fluid to a patient at a programmed therapy flow rate, air-in-line sensing is improved by commanding the pumping mechanism to deliver a bolus volume of fluid at a flow rate higher than the therapy flow rate when an uninterrupted volume of air is detected that exceeds a first threshold. In many cases, the bolus will be effective to clear microbubbles from an observation zone of the air-in-line sensor to avoid an air-in-line alarm condition. If the uninterrupted volume of air continues to grow beyond a second threshold in spite of the bolus, then an alarm may be triggered. The invention reduces false alarms.

Abstract: A method for forming peristaltic pump cassettes includes cutting tubing segments to different lengths based on the physical properties of the individual tubing segments. The size variations compensate for the physical parameters of the tube and improve accuracy in a peristaltic pump using the cassettes.

Abstract: Methods for improving the accuracy of occlusion sensor baselines in an infusion pump are described. An infusion pump includes logic for making an antiratchet decision for determining whether a new administration set was installed after there has been access to the administration set. If so, then new occlusion sensor baselines are established. If not, then the current baselines are maintained. The antiratchet decision logic may depend upon the value of a baseline delta equal to a difference between the upstream sensor signal and the downstream sensor signal. In another aspect, an upstream occlusion sensor baseline is shifted in correspondence with decreases in the upstream sensor signal occurring while a pumping mechanism of the infusion pump is not operating to compensate for sensor signal drift.

Abstract: An automatic safety occluder provides an occluder for an infusion set that is biased in a closed position until an electrical signal is received that causes the occluder to open. Should the occluder fail to be installed correctly, or if power is removed, the occluder will return to its biased closed position, preventing free flow. The occluder may also be placed in an integrated unit such that the automatic safety occluder may attach to the tubing as a unit.

Abstract: A sensor and method of use provides for detection of an occlusion (or sudden pressure increase) in tubing during the administration of solutions to a patient. The occlusion sensor may be attached to an infusion pump using a biasing mechanism. The tubing may be positioned in contact with the occlusion sensor using a cassette. Detection of an occlusion in the tubing is accomplished by measuring the compression and expansion of the tubing. When the tubing becomes occluded pressure within the tube will increase, resulting in expansion of the tubing. Expansion of the tubing exerts a force on the sensor to trigger an alarm to alert medical personnel of the occluded tube.

Abstract: Current phacoemulsification handpieces require rigorous cleaning after each procedure because the aspiration and irrigation pathways for fluids are integral to the handpiece. According to the present invention, a removable horn extension and nosecone may be used with a phacoemulsification handpiece to allow for disposable fluid pathways exterior to the handpiece. This will reduce the cleaning time and effort, reduce cross-contamination, and increase the lifespan of the handpiece. Furthermore, the current invention allows different horn extensions to be used to excite different motions at the tip of the handpiece, depending on the preference of the surgeon.

Abstract: An anti-free-flow mechanism includes an occluder mechanism which is disposed along a segment of tubing. The occluder mechanism is normally in a biased closed position, but may be moved into an open position by moving an engagement member into engagement with the tubing segment to deform the tubing segment and open a flow channel. Unless force is applied to keep the engagement member in contact with the tubing segment, the tubing will return to the first, closed position.

Abstract: A Langevin transducer horn uses split electroding or selective electroding of transducer elements and phase relationships of the voltages applied thereto to determine the relative longitudinal and flexural/transverse motion induced in the tip of the horn.

Abstract: A Langevin transducer horn uses split electroding or selective electroding of transducer elements and phase relationships of the voltages applied thereto to determine the relative longitudinal and flexural/transverse motion induced in the tip of the horn.

Abstract: An anti-free-flow mechanism includes an occluder mechanism which is disposed along a segment of tubing and a mounting structure. The occluder mechanism is normally in a biased closed position, but may be moved into an open position by placement in the mounting structure. However, unless force is applied to keep the occluder mechanism in the mounting structure, the occluder will move relative to the mounting structure and return to the first, closed position.

Abstract: Air bubbles may be characterized by an air bubble detector by choosing an optimum set of frequencies and then comparing a return signal from a sensor receiving those frequencies against an internal reference. The number of pulses that exceed the internal reference represents a width and may be counted. The width, as counted, may be correlated to bubble characteristics including volume.

Abstract: Air bubbles may be characterized by an air bubble detector by choosing an optimum set of frequencies and then comparing a return signal from a sensor receiving those frequencies against an internal reference. The number of pulses that exceed the internal reference represents a width and may be counted. The width, as counted, may be correlated to bubble characteristics including volume.

Abstract: A Langevin transducer horn uses split electroding or selective electroding of transducer elements and phase relationships of the voltages applied thereto to determine the relative longitudinal and flexural/transverse motion induced in the tip of the horn.

Abstract: A universal air bubble detector allows for use with a variety of sizes and types of tubing. The detector maintains proper alignment of a sensor emitter and receiver with different sizes of tubing. The detector may be mounted on existing equipment or may be used to monitor a tubing at any position along the tubing, and may operate in a stand alone mode or in combination with existing equipment.

Abstract: An automatic safety occluder provides an occluder for an infusion set that is biased in a closed position until an electrical signal is received that causes the occluder to open. Should the occluder fail to be installed correctly, or if power is removed, the occluder will return to its biased closed position, preventing free flow. The occluder may also be placed in an integrated unit such that the automatic safety occluder may attach to the tubing as a unit.