Abstract: The present invention provides an accurate method and apparatus for monitoring the drop flow rate from a fluid source. The drops are indirectly sensed by piezoelectric means mounted on a drip chamber when the drops impinge on a fluid surface in the chamber. The chamber can include a second differential piezoelectric sensing element, which provides a noise reference signal which can be subtracted from the drop sensing signal. The volume of the fluid drops sensed can be determined. The sensing element can be incorporated in open and closed loop disposable chamber modules which can include both monitoring and occlusion valving functions integral therewith.

Abstract: The present invention provides an accurate method and apparatus for sensing and monitoring any buildup in the downline tubing pressure in a fluid infusion system. The initial fluid pressure as indicated by the tubing location is sensed after a delay period and is utilized as a base pressure if it is within allowable limits. The infusion tubing location or pressure is then monitored and compared with the base location or pressure. The system will alarm if a preset differential location or pressure change is exceeded.

Abstract: The present invention provides an uncomplicated quick disconnect rotor assembly for peristaltic pumps. The assembly includes a magnetic carrier mounted on the pump drive shaft which has a mating configuration with a recess in the rotor. The rotor includes at least one magnet, preferably with segments on opposite sides of an axial drive shaft alignment passageway. The carrier and rotor are assembled and held in operation only with the magnetic force therebetween, which eliminates tools and mechanical moving parts from the assembly.

Abstract: The present invention provides a fast, efficient, precise method and apparatus for compounding solutions for use in hyperalimentation therapy. The apparatus includes a controller for entering the volume and specific gravity of the solution to be compounded.A load cell monitors the weight of the solutions that have been transferred to a collection vessel and in connection with the controller thereby maintains the precise amount of each therein. The controller also surveys various process conditions and warns of any failure of those conditions. Peristaltic pumps are used for the delivery of the compounding solution to maintain the solutions in a sterile condition.

Abstract: The present invention provides an accurate method and apparatus for monitoring the drop flow rate from a fluid source. The method and apparatus allows for an intermittent drop flow rate by accumulating a weighted drop period rate error factor which is adjusted for each drop period detected.A drop period window is adjusted by each drop period and is utilized to determine if the current drop period is within the window indicating a normal operation. Drop periods outside the window cause a factor to be added to the accumulated error factor and drop periods within the window cause a factor to be subtracted from the accumulated error factor. This allows good periods to offset bad periods, so that minor fluctuations in the drop periods during normal operation can be ignored.

Abstract: A temperature independent dosimeter is provided for measuring an amount of irradiation of a predetermined frequency. A photodiode (24) operating in its photovoltaic mode is irradiated with the irradiation to produce a signal that is amplitude-proportional to the amplitude of the irradiation. The signal is converted by a pair of operational amplifiers (89, 96) to a plurality of pulses that are proportional in frequency to the amplitude of the signal. The plurality of pulses is counted by a counter (20) and the irradiation is terminated when the count reaches a predetermined amount.

Abstract: The present invention provides an economical quick and accurate method and apparatus for transferring and monitoring a preselected amount of fluid from a fluid source container to a receiving container. The method and apparatus monitors the flow rate of the fluid to be transferred by measuring the weight change of the receiving container per unit time.A weight sensor monitors the weight of the receiving container at various time intervals. The weight information received by the control module at the various time intervals is compared to each other and to predetermined values for the detection of no flow, low flow or high flow conditions.

Abstract: Patients having a clotting factor defect can be successfully treated by the administration of a composition containing effective hemostatic amounts of factor VIIa. Preferably, the factor VIIa is substantially free of factors IXa and Xa. Procedures for preparing the above therapeutic compositions are also described. A method involving the activation of factor VII is set forth.

Abstract: A circuit is provided for resetting a digital logic circuit, such as a digital counter. A switch 16 provides a first signal when a predetermined condition has occcurred. A flip-flop 24 provides an output reset signal when the flip-flop is in a first state, in response to the first signal. The digital logic circuit to be reset 32 is coupled to the output of the flip-flop 24 for receiving its output reset signal. Feedback means 34, 36, 38 are coupled from the digital logic circuit 32 back to the flip-flop 24 for providing a signal to put the flip-flop into its other state whereby its output reset signal is terminated.

Abstract: The fluid dispensing device (10) is utilized in a fluid dispensing system (12) which includes a syringe (22) having a cylindrical barrel (36) with an inlet/outlet opening (20) at a forward end thereof and which is open at the rearward end thereof. A plunger (38) is received in the barrel (36). A source (14) of medicinal additive is coupled by a two-way check valve (18) to the inlet/outlet opening (20). A needle (24) is mounted to the outlet (26) of the valve (18).The fluid dispensing device (10) is manipulatable to operate the syringe (22), first to draw a precise amount of medicinal additive into the syringe (22) through the valve (18) and second to dispense the precise amount of medicinal additive from the syringe (22) through the needle (24) into, for example, a receptacle (34) having a base liquid therein.

Abstract: A process and device are provided for detecting frequency variations of waveforms (10). The waveform (10) is sensed and a first signal (16) is provided with each occurrence of the sensed waveform (10). Each time that the first signal is provided, a measuring pulse (24) that is different in duration than the sensed waveform (10) is provided. The sensed waveform (10) and the measuring pulse (24) are simultaneously transmitted to a gate (28) which provides a signal at its output to indicate if the frequency of the sensed waveform has varied more than a predetermined amount.

Abstract: Dynamically changing time-multiplexed numbers are presented by reading data one digit at a time, storing the digits, repeating the reading sequence at least twice and comparing the stored digits from each reading sequence against the stored digits from the previous reading sequence. If two consecutive reading sequences are not identical, the reading sequence is repeated at least twice again.

Abstract: A parenteral solution administration system having a conduit for communication with a source of parenteral solution, a drip chamber carried by the conduit, drop detector circuit for detecting drops falling through the drip chamber and flow control circuit including an occlusion device moving between first and second positions for opening and closing the conduit. Feedback circuit is provided for controlling the flow control circuit to cause the rate of drops falling through the drip chamber, as sensed by the drop detector circuit, to correspond to a predetermined drop rate. The occlusion device is preferably operated by a stepper motor, and the system is disengagable so that at the occurrence of a predetermined circumstance, the occlusion device can be disengaged from the motor circuit and can be moved without corresponding action of the motor circuit.

Abstract: An improved nephelometer for immunochemical complex assay measures forward light scatter in samples. The angle of forward scatter, about 30.degree., is small enough to result in a large amount of forward scatter from the immunochemical complex particles which are to be assayed, whose size is of the order of the wave length of the light used in the optical system. Forward scattering from smaller particles, such as from molecules of buffer, antibody and serum, is constant during the course of a test, and is compensated for by the use of subtraction circuits which are readily and semiautomatically adjusted to subtract proper values, in accordance with the readings taken on standard or "blank" samples of buffer, antibody and serum. Forward scattering from large particles, such as dust, is variable, and results in fluctuating signals, which are electrically processed to ignore the spurious peaks. The results of a test are displayed on a digital read out meter.

Abstract: A centrifugal analyzer and method for performing chemical reaction measurements. A cuvette ring (60) is positioned on a rotor (36) encircling a shaft (40). A carrier member (62) defining a central aperture (92) is positioned within the central opening of the cuvette ring (60). The carrier member (62) defines a plurality of slots (100), each of which receives a disposable container-like insert (130). The inserts (130) may carry a precoating of an agent for use in an in vitro diagnostic test. Each insert has a slot (136) for enabling centrifugal transfer of the liquid in the insert through the slot, through the aperture (122) defined by the peripheral wall of the carrier member (62), and into a respective cuvette cell.

Abstract: The photometer is adapted for sensing radiation emitted by a chemical sample held in a cuvette received in a first compartment and includes a highly sensitive photomultiplier in a second compartment adjacent the first compartment for detecting fluorescent radiation emitted by the chemical sample and passing through an opening between the compartments. A mechanical protector assembly is provided for protecting the photomultiplier from ambient light and includes a movable light shield movable between a first position blocking the opening and a second position not blocking the opening. A knob is provided for moving the light shield to the first position to protect the photomultiplier from light entering from the first compartment when the first compartment is opened for insertion or removal of a cuvette, and for moving the light shield to the second position not blocking the opening to permit radiation emitted by the chemical sample to impinge upon the photomultiplier in the second compartment.

Abstract: The method for separating whole blood into the components thereof is practiced with and within a separation chamber mounted in a centrifuge device during centrifugation of the chamber, the chamber having inner and outer wall surfaces and first and second side edges. The method comprises the steps of: arranging and configuring the chamber such that it has (a) an inlet on the first side thereof through which whole blood is received, (b) a first upper outlet at the top of the chamber from which plasma with particles therein is withdrawn, (c) a second lower outlet at the bottom corner of the chamber on the second side thereof from which red blood cells are withdrawn, and (d) the inner wall surface positioned in a plane including a tangent to a circle about the axis of rotation and the plane positioned about normal (in a vertical direction) to a radius extending from the axis of rotation of the centrifuge device.

Abstract: An improved nephelometer for immunochemical complex assay measures forward light scatter in samples. The angle of forward scatter, about 30.degree., is small enough to result in a large amount of forward scatter from the immunochemical complex particles which are to be assayed, whose size is of the order of the wave length of the light used in the optical system. Forward scattering from smaller particles, such as from molecules of buffer, antibody and serum, is constant during the course of a test, and is compensated for by the use of subtraction circuits which are readily and semiautomatically adjusted to subtract proper values, in accordance with the readings taken on standard or "blank" samples of buffer, antibody and serum. Forward scattering from large particles, such as dust, is variable, and results in fluctuating signals, which are electrically processed to ignore the spurious peaks. The results of a test are displayed on a digital read out meter.

Abstract: The method includes the steps of: placing blood in a transparent tubing; passing intense, coherent light through the tubing and blood; sensing the light passed through the tubing and blood; and, producing a signal related to the amount of transmitted light sensed and indicative of the hematocrit of the blood. The apparatus includes a laser light source for generating the intense, coherent light beam at a wavelength in the red spectrum and an optical photodetector including a silicon diode positioned to receive the transmitted light and an amplifier circuit.