Abstract: A blood pressure measuring system includes a transducer having first and second sensors adapted to be mounted above the artery of a patient with the second sensor more distal relative to the direction of blood flow than the first sensor. A processor digitizes the signals from the first and second sensors and determines when the second signal is phase shifted about 90 degrees relative to the first signal for determining the occurrence of the Korotkoff sound. The transducer comprises a film of a material having piezoelectric properties and at least two spaced apart electrodes on one surface of the film and a third electrode on the opposite side and opposed to the two electrodes.

Abstract: A method and apparatus for simultaneously displaying a plurality of time variables indicative of the condition of a dynamic system. The system is constructed and arranged to be coupled to an array of sensors each positioned for sensing a discreet signal functionally related to one of the variables and includes an acquisition module coupled to the sensors for generating time variable signals indicative of the variables, a sorter for sorting the data into rows, and a processor receiving the rows of data and for computing a function for each variable, and means for determining a color coded plot value for each computed function.

Abstract: A blood pressure measuring system includes a transducer having first and second sensors adapted to be mounted above the artery of a patient with the second sensor more distal relative to the direction of blood flow than the first sensor. A processor digitizes the signals from the first and second sensors and determines when the second signal is phase shifted about 90 degrees relative to the first signal for determining the occurrence of the Korotkoff sound. The transducer comprises a film of a material having piezoelectric properties and at least two spaced apart electrodes on one surface of the film and a third electrode on the opposite side and opposed to the two electrodes.

Abstract: An infrared gas analyzer and method employing one optical path which includes one infrared source, one sample cell containing the gas(es) to be analyzed, one infrared sensor and one infrared filter no matter how many gases are to be analyzed. The one optical path with one filter is utilized for both determining infrared source output and infrared absorption by the gas(es) to be measured.

Abstract: A signal acquisition method comprises the steps of recording ECG data signals on a tape in a first direction through a first high pass filter; and acquiring the data from the tape in an analyzer in a reverse direction through a second high pass filter having the same effective characteristics as the first filter.

Abstract: A cardiac monitoring system includes an acquisition module for acquiring a plurality of analog cardiac signals through leads connected to predetermined locations on the body of a patient and for converting the cardiac signals to twelve standardized ECG lead signals. An arrhythmia monitor analyzes a plurality of the ECG signals for determining the existence of rhythm abnormalities and a twelve lead analyzer analyzes both the rhythm and the contours of all of the ECG lead signals for rhythming conduction, infarction, hypertrophy and repolarization abnormalities. The arrhythmia monitor and the twelve lead analyzers are operated concurrently for the simultaneous analysis of the ECG signals so that the occurrence of a rhythm abnormality and its cause can be determined on a real time basis.

Abstract: A method and gas analysis system for a mass spectrometer including an ion pump for creating an internal vacuum within said mass spectrometer, an ionization chamber, an inlet passage through which a gas sample is introduced into the ionization chamber, valve means associated with the inlet passage for controlling the volume of gas sample introduced into the ionization chamber, a filament for introducing electrons into the ionization chamber whereby the electrons bombard the gas sample thus forming ions, an extractor plate positioned adjacent the ionization chamber and biased such that a proportion of ions and electrons are allowed to pass through the extractor plate, a quadrupole filter into which the ions and electrons are directed by the extractor plate, the quadrupole filter operative to permit a stream of ions with a pre-selected mass-to-charge ratio to pass through the filter and ions other than those having the pre-selected mass-to-charge ratio being separated from the stream of ions, means for directing

Abstract: An electrical connector assembly includes a terminal block having a plurality of spaced contact pins mounted thereon and oriented in a first direction. A plurality of openings are formed in the terminal block and each is aligned with one of the contact pins. A plurality of sockets are each mounted at the end of a lead wire and are constructed and arranged to be received in any one of the openings for electrically engaging the contact pin aligned therewith. A locking bar has a plurality of locking portions and is pivotally mounted on the terminal block for movement between an unlocking position and a locking position wherein the locking portions are respectively aligned with one of the openings. A biasing spring engages the locking bar for biasing the locking bar toward its locking position.

Abstract: A windowing control for a video display includes a programmed controller, a video display including a screen and a raster for scanning the screen, a first memory having a first area for storing data to be displayed in a first window defined on the screen and a second area for storing data to be displayed in a second window on the screen and a second memory for storing the addresses of the data to be displayed in the first and second windows and the transitions between the windows. The controller includes a processor programmed to load data into the first and second memory means and a memory controller for initiating the transfer of data from the first and second memory to a pixel multiplexer. The processor is also programmed to load new address data into the second memory means for each complete raster scan so that the position of the data within the window has the appearance of horizontal (panning) or vertical (scrolling) movement.

Abstract: An oximetry sensor constructed including first and second opposed shell members for engaging the opposite sides of a patient's finger. A coupler releasably connects a pair of LEDs to the first member for projecting light through the finger and a light detector is mounted on the other member for detecting unabsorbed light transmitting through the finger. One of the shell members is mounted for sliding movement on the other for engaging the opposite sides of the patients finger and a coupler retains the shell members in position. In a first embodiment, the LED's are directly releasably coupled to the first member and in a second embodiment a fiber optic cable releasably couples the LED's to the first member.

Abstract: A patient monitoring system includes a plurality of leads adapted to be coupled to a patient for generating individual ECG data voltage signals. A switching matrix couples the leads to a plurality of differential circuits for coupling selected pairs of the ECG voltage signals to each of the differential circuits for generating differential ECG vector signals functionally related to the difference between selected pairs of the ECG voltage signals. A microprocessor is coupled to the leads and to the switching matrix and is operative to reset the switching matrix to uncouple one or more first leads from the differential circuits and for coupling one or more different ones of the ECG voltage signals to differential circuit formerly coupled to receive the voltage signal from the one or more first leads.

Abstract: A method of monitoring natural electrical impulses from a patient's heart, and providing appropriate therapeutic electrical impulses to a patient's heart comprising the steps of placing on the patient's chest an electrode pad having a plurality of electrode sites arranged such that at least one electrode site is disposed sufficiently near the patient's right arm to intercept an adequate right arm signal, at least one electrode site is disposed sufficiently near the patient's left arm to intercept an adequate left arm signal, and a plurality of additional electrode sites disposed approximately therebetween.

Abstract: A patient monitoring system includes a plurality of leads adapted to be coupled to a patient for generating individual ECG data voltage signals. A switching matrix couples the leads to a plurality of differential circuits for coupling selected pairs of the ECG voltage signals to each of the differential circuits for generating differential ECG vector signals functionally related to the difference between selected pairs of the ECG voltage signals. A microprocessor is coupled to the leads and to the switching matrix and is operative to reset the switching matrix to uncouple one or more first leads from the differential circuits and for coupling one or more different ones of the ECG voltage signals to differential circuit formerly coupled to receive the voltage signal from the one or more first leads.

Abstract: A patient monitoring system includes a plurality of leads adapted to be coupled to a patient for generating individual ECG data voltage signals. A switching matrix couples the leads to a plurality of differential circuits for coupling selected pairs of the ECG voltage signals to each of the differential circuits for generating differential ECG vector signals functionally related to the difference between selected pairs of the ECG voltage signals. A microprocessor is coupled to the leads and to the switching matrix and is operative to reset the switching matrix to uncouple one or more first leads from the differential circuits and for coupling one or more different ones of the ECG voltage signals to differential circuit formerly coupled to receive the voltage signal from the one or more first leads.

Abstract: Heating pattern uniformity is provided in a coaxial microwave hyperthermia probe by varying the open area in the outer conductor in an axial direction such that there is a maximum open area in the axial center portion. The variations may be provided by winding an outer conductor in a helical pattern with a variable pitch or by cutting openings of axially varying size in a solid outer conductor. The invention is applicable to both flexible and rigid probes.

Abstract: A monitoring system for providing continuous monitoring of a patient, including periods of transport, includes a data acquisition and processing module receiving physiological data from the patient. The module may be inserted in a bedside display unit to display the physiological condition data being monitored. The module may also be inserted in a portable display unit that can accompany the patient during transport. Connectors permit the module to simultaneously drive both the display units so that no data is lost when the module is removed from the bedside unit and placed in the portable unit and vice versa.

Abstract: A chart recorder has a writing platen over which a moving strip of recording medium passes. The recording medium is Z folded along slotted lines. The tip of the tubular pen of a pressurized ink supply system is forced into contact with the strip as it passes over the platen. A pressure plate is positioned adjacent the pen for pressing the strip onto the platen. A capstan drive is located downstream of the writing platen to draw the strip off a Z folded supply stack past the pressure plate and over the writing platen. The pressure plate exerts a drag on the recording medium strip which tensions the strip to further cause it to lie flat across the writing platen. The pressure of the plate and the tension of the strip as well as the size relationship between the pen tip and the slots facilitate passage of the pen over the lines of slots.

Abstract: A stepping motor rate control employs a predetermined energization of one quantity to step the motor and a lower, predetermined quantity of current energization to hold the motor in position as by using a current pulse to hold the motor. The frequency of energization of the motor is constant; the speed of the motor being determined by the ratio of stepping pulses to holding pulses.The stepping motor rate control is driven from a clock. A duty cycle divider reduces the clock frequency down to the energizing frequency of the stepping motor. An energizing pulse is applied to the motor during each cycle. A divide-by-N-divider, coupled to the duty cycle divider, is used to determine the ratio of stepping energization pulses to holding energization pulses to be provided to the motor and hence the speed of the motor.