Abstract: The optical interrupter system includes a moving member having a sequence of optical flags, interposed between a source of illumination and a detector, such that as the optical flags of the moving member are illuminated and detected, the detector generates a signal having a waveform with a first portion less than a first threshold, a second portion greater than the first threshold and less than a second threshold, and a third portion greater than the second threshold. Signal processing circuitry operates to generate a count signal indicating a transition between the first and third waveform portions.

Abstract: The clamp for flexible tubing may be used in conjunction with an infusion pump instrument or separately. The clamp includes a pair of elongated clamping members pivotally hinged together and biased to clamp a segment of flexible tubing received between the clamping members. A latch is also preferably provided for allowing the clamping members to be releasably latched apart. The latch, and the elongated clamping members are arranged in a manner such that when the clamp has a segment of flexible tubing received between the clamping members and the clamp and tubing are set between the housing and door of an infusion pump, closing the door causes the clamp to release to an open position allowing fluid flow, and opening the door causes the clamp to automatically move to a closed position, clamping the tubing so as to prevent fluid flow.

Abstract: The apparatus accurately measures flow rate of fluid within a conduit without direct fluid contact, based on the introduction of a thermal marker into the fluid stream by means of at least one externally mounted heater, and detection of the thermal marker by means of at least one externally mounted sensor. The transit time of the thermal marker can be ascertained for transit of the thermal marker from a heater to a sensor, or from one sensor to another sensor. A preferred embodiment of the heater comprises a resonant microwave cavity which heats the fluid radiatively, and a preferred embodiment of the sensor comprises a resonant microwave cavity through which a portion of the fluid conduit passes, the resonant characteristics of said microwave sensor being perturbed by the passage of the thermal marker.

Abstract: The negative pressure monitor is intended for use in combination with an IV administration set, for monitoring venous, arterial and other physiological pressure signals. The system provides a coupling mechanism with a sealed vacuum chamber between a fluid chamber in communication with the fluid in line, and the pressure transducer. The vacuum in the coupling mechanism serves not only to communicate pressure changes within the fluid chamber to the pressure transducer, but also functions to maintain the fluid chamber in pressure communication with the pressure transducer.

Abstract: The infrared thermometer optical chopper includes a planar shutter having infrared radiation transmissive and infrared reflective portions arranged on the shutter, and a mechanism for rotating the shutter sequentially through a series of stop positions in which the transmissive and reflective portions are sequentially aligned with the internal optics of the infrared thermometer. A mechanism is also preferably provided for sensing the positioning of the shutter at the stop positions, to determine whether the shutter stop position alignment is in an infrared radiation transmissive phase or in an infrared radiation reflective phase.

Abstract: A prime mover module used in a fluid delivery micropump, especially for pharmaceutical purposes, transports an electrochemically active material, such as oxygen, at a steady rate across an ion exchange cell to apply external pressure to a collapsible reservoir and expel fluid therefrom. An air-actuated battery, such as a zinc-air battery, which is located in the module in a fixed closed circuit with the cell and which shares one of its electrodes with the cell, is activated by peeling off an adhesive tape covering air inlet ports to thereby establish a voltage gradient acrosss the cell and control the rate at which fluid is expelled from the reservoir in accordance with the value of a resistor in the cell/battery circuit. The reservoir is filled or refilled by inserting a vented needle into an air bleed port while discharging a fluid-filled syringe inserted into a fluid injection port.

Abstract: A biomedical thermometer for taking the temperature of a person at various body sites, including the ear, includes a radiation detector, a temperature detector for measuring the temperature of the radiation detector, and a heating and cooling unit for changing the temperature of the radiation detector. The system also includes a temperature processor for generating an output proportional to the absolute temperature of the radiation detector, responsive to signals generated by the radiation detector and the temperature detector.

Abstract: An electrochemically driven drug dispenser for dispensing a drug at a controlled rate. The drug dispenser includes an electrochemical pump which pumps an electrochemically active fluid from a first compartment through a membrane into a scond compartment. As the fluid enters the second compartment it exerts pressure on a diaphragm separating the second compartment from a chamber containing a drug to be administered. As the pressure increases, the drug is expelled. In the absence of any pumping action, the fluid moves between the two compartments by diffusion through the membrane at a rate which is characteristic of the membrane and determined by any pressure difference between the two compartments. The pumping rate is determined by the magnitude of an electric current applied to the pump, and by varying the pumping rate with reference to the diffusion rate any of a variety drug administration rates can be implemented. A pressure sensor may be included in the pump for more precise control of the pumping rate.

Abstract: The invention is directed to a fluid flow monitoring method and system for parenteral fluid delivery systems for use in situations, such as with sedentary patients, when wide pressure variations are not expected. The resistance of the fluid delivery system is determined from the ratio of pressure differences at high and low fluid flow rates to differences in the high and low fluid flow rates. The resistance is used to develop a pressure limit from the sum of the pressure at low fluid flow rates and the product of the resistance and the high fluid flow rate. The pressure limit is compared with the pressure monitored and if the pressure monitored exceeds the calculated pressure limit, an alarm is actuated to warn medical personnel of an occlusion or other fluid flow fault. Additionally, if the noise level (pressure) excess predetermined limits during the periods of low and high fluid flow, the pressure monitoring is terminated.

Abstract: A device for infusing a drug into an ambulatory patient, the drug being contained in a transparent spiral conduit which is embedded in a disposable flexible casting conformingly adhered to the patient's body, includes a reusable micropump module which is detachably mounted in a collar valve on the casting and forces oxygen into the conduit under pressure to expel the drug into a semi-pivoting cannula inserted into the patient's body. A colored oil drop between the oxygen and the drug in the conduit provides a visual indication of drug quantity, while a filter with hydrophobic and hydrophylic membranes keeps the oxygen and oil substantially out of the cannula.

Abstract: This invention is directed to a method and system for evaluating the fluid communication between a parenteral fluid delivery system and a patient's blood vessel. In accordance with the invention, one or more fluid flow pulses are applied to the fluid within the delivery system. Both positive and negative fluid flow pulses may be applied. The pressure response to the pulses under conditions of normal, unimpeded fluid flow is significantly different than the pressure response to such pulses when an infiltration or other fluid flow fault has occurred and this difference is used to detect fluid faults.

Abstract: An improved drug dispenser for the pulsatile or peristaltic delivery of drugs. The drug dispenser includes a fluid reservoir for storing the drug to be dispensed, an electrochemical pump for pumping the drug from the fluid reservoir, and a pump valve responsive to the pump pressure such that when the pump pressure reaches some predetermined value, the pump valve releases the pressure exerted upon the drug. The result is a low cost, low weight ad efficient drug dispenser for the pulsatile delivery of drugs.