Abstract: An apparatus and method for distinguishing between different types of apneic episodes. The method includes measuring a new index, TCD/VT, and measuring the phase relation between the abdominal and rib cage contributions to total respiration volume. The episode is classified as central, obstructive or mixed based on the value of TCD/VT and the phase relation.

Abstract: An apparatus comprised of a canister having a valved opening thereon and containing, under pressure, heparin and a low boiling point propellant is disclosed. The valved opening can be activated to release a metered dose of aerosolized heparin to a patient or preferably to an inhalation device which improves efficiency with respect to the amount of heparin reaching the lungs of the patient.

Abstract: The presence and origin of apnea in a newborn subject is detected by separately and concurrently monitoring relative movement of the cranial bones and nasal ventilation. The cranial bones have been found to move with respiration as a function of intrapleural pressure, and monitoring of their movement is accordingly used to generate a signal representative of intrapleural pressure. A nasal cannula, thermistor, thermocouple or CO.sub.2 sensors are employed to concurrently generate a signal representative of tidal volume. Absence of changes in both cranial bone movement and respiratory air flow at the nose is indicative of the presence of central apnea, while absence of nasal air flow accompanied by continuing cranial bone movements is indicative of obstructive apnea. The preferred device for detecting cranial bone movement is a surface inductive plethysmographic transducer, although other suitably sensitive motion detecting devices may be employed.

Abstract: A method for monitoring cardiopulmonary events is disclosed. The basic method comprises looping an extensible conductor (14) in close encircling relation about the neck (12) of the subject (10), providing a signal indicative of the inductance of the loop, and monitoring the signal. This signal contains both qualitative and quantitative cardiopulmonary information. In accordance with another aspect of the method, an extensible conductive loop (14) is disposed in close encircling relation about the head such that the plane defined by the loop extends through the mouth. By providing a signal indicative of changes in the inductance of the loop, qualitative and quantitative information for mouth volume may be obtained.

Abstract: A method of permitting restful sleep at high altitudes is disclosed involving administration to a patient susceptible to Cheyne-Stokes respiration of a pharmaceutically acceptable amount of an endorphin-blocking compound capable of blocking the action of endogenous endorphins, whereby sleep interruptions characteristic of Cheyne-Stokes respiration are alleviated. There is also disclosed a method of permitting a continuous flow of oxygen to the brain cells in a sleeping patient otherwise susceptible to repeated interruptions of breathing that would retard the necessary steady flow of oxygen to brain cells to maintain their viable condition, which comprises administration prior to retiring of a pharmaceutically acceptable amount of an endorphin-blocking compound capable of blocking the action of endogenous endorphins to substantially obviate sleep interruptions that otherwise would occur.

Abstract: A subject rebreathes an inert aerosol from a closed system and, during each of a plurality of breaths, the aerosol concentration in the closed system is determined and compared to determine differences with a predetermined concentration value. Identified differences indicating enhanced aerosol deposition signify airway narrowing and/or an increase in accumulated airway secretions.

Abstract: A method and an apparatus for administering a drug through a breathing passage for absorption on the mucous tissue of a patient includes introducing an aerosol of the drug into an expanded bag and bidirectional channel for communicating the drug with the breathing passage of the patient and otherwise is substantially impervious to the passage of air, collapsing the expanded bag while the bidirectional channel for communicating with the breathing passage is in position to deliver the drug into the breathing passage of the patient. A signal in a bidirectional channel indicates when the rate of passage of the drug exceeds a desirable limit, whereby the patient taking the drug is reminded to decrease the rate of collapse of the airbag, thereby maximizing drug utilization.

Abstract: A method of semiquantitatively measuring a subject's neck volume includes the steps of providing an extensible conductor in the form of a loop having a predetermined height; providing a signal variably responsive in value to changes in the inductance of the conductor; calibrating the signal by determining reference signal values obtained with the conductor disposed about at least two known volumes and using the reference signal values to establish the relationship between signal value and the volume enclosed by the conductor; disposing the conductor in close encircling relationship about the subject's neck; calibrating the signal for intrapleural pressure by using an invasive technique as a reference for determining a plurality of intrapleural pressures for the subject and simultaneously determining the signal value for each such intrapleural pressure measurment, thereby establishing the relationship between intrapleural pressure and signal value; discontinuing the reference technique; determining the signal

Abstract: A method for monitoring cardiopulmonary events is disclosed. The basic method comprises looping an extensible conductor (14) in close encircling relation about the neck (12) of the subject (10), providing a signal indicative of the inductance of the loop, and monitoring the signal. This signal contains both qualitative and quantitative cardiopulmonary information. In accordance with another aspect of the method, an extensible conductive loop (14) is disposed in close encircling relation about the head such that the plane defined by the loop extends through the mouth. By providing a signal indicative of changes in the inductance of the loop, qualitative and quantitative information for mouth volume may be obtained.

Abstract: A device for measuring a predetermined respiratory volume comprises an elongate, air-tight flexible bag of the predetermined volume, the bag being closed at one end and open at the other; and an elongate substantially rigid tubular member extending into the bag through its open end and occupying a major portion of the length of the bag, the bag being secured at its open end to the tubular member for forming an air-tight seal between the bag and the tubular member, the portion of the tubular member extending into the bag having a plurality of distributed apertures along its length and the portion of the tubular member outside the bag having at least one opening defining a mouthpiece.

Abstract: A method and apparatus are shown for monitoring respiration volumes by continuously measuring, while the patient breathes, variations in the patient's chest cross sectional area, or preferably, variations in both chest and abdomen areas. Each area is measured by measuring the inductance of an extensible electrical conductor closely looped around the body, by connecting the loop as the inductance in a variable frequency LC oscillator followed by a frequency-to-voltage converter and a voltage display. Calibration is made by measuring the area variations for a few breaths while directly measuring corresponding volumes of breath, preferably while the patient assumes at least two body positions, for example sitting and supine. The method and apparatus may also be used to monitor changes in area of any non-magnetic object.

Abstract: A suction catheter in which an elongate flexible plastic tube having an open distal tip is provided with axially extending flanges at its distal end with apertures extending through the wall of the catheter between the flanges.