Abstract:
A respiration monitor for monitoring respiration of an individual comprising a sending light conductor (12) and a receiving light conductor (18). The sending light conductor (12) and the receiving light conductor (18) are held in a position generally near a portion of the individual which moves in response to the respiration motion of the individual. More particularly, the ends (16, 20) of the sending light conductor (12) and the receiving light conductor (18) are spaced a distance (28) apart and positioned so that the distance between the end (16) of the sending light conductor and the end (20) of the receiving light conductor varies in response to respiration motion of the individual. A light source (100) emits light which is received by the sending light conductor (12) and transmitted therethrough across the distance (28) between the ends (16, 20) of the sending light conductor and the receiving light conductor, such light being received by the receiving light conductor (18) and transmitted therethrough. The light from the receiving light conductor (18) is received and indications (30) of respiration motion are determined in response to changes in the intensity of the light received from the receiving light conductor (18) and output indications (30) are provided indicative of respiration motion.
Abstract:
Method for non-invasively measuring respiration volume whereby weighting factors are non-invasively determined by (a) totaling delta values over a baseline period of substantially steady state breathing for obtaining a rib cage signal, (b) totaling delta values over a baseline period of substantially steady state breathing for obtaining an abdominal signal, (c) dividing the average variability of the mean of the total of the delta values for one of either the rib cage or abdomen signals by the average variability of the mean of the total of the delta values for the other of either the rib cage or abdomen signals; and (d) multiplying the other signal by the quotient derived from step (c).
Abstract:
An adaptor assembly for sampling gas in an airway tube attached to a patient. The adaptor assembly employs a filter arrangement (17) in a subassembly (15) which extends transversely of the axis of the pateint's airway and maximizes the ratio of the effective filter area of the dead volume added by the adaptor assembly to the sampling system.
Abstract:
Method and apparatus for determining the partial pressure of carbon dioxide in the arterial blood of a patient. The method and apparatus are particularly useful where the patient is under anesthesia. Carbon dioxide concentration is measured at the end tidal of the patient's exhaled breath. Nitrous oxide concentration is also measured so that the measured values of the carbon dioxide concentration may be corrected in accordance with the measured value of the nitrous oxide concentration. Particular wavelengths of detection are described, together with other apparatus parameters to provide a high level of accuracy.
Abstract:
The resuscitator unit (10) has a plurality of bellows assemblies (20) cyclically actuated, by motor (62) through a drive train (52, 58, 60) to provide pressurized air through a plurality of valved conduits (14) to the associated face masks (12) for simultaneous resuscitation of a plurality of patients.
Abstract:
Apparatus for providing a measure of extravascular lung water of a subject using a single thermal indicator, including means (16) for providing an injection of the thermal indicator into the bloodstream of the subject at a position proximal to or in the right heart (10), means (26) for detecting a first time-temperature concentration curve of the bloodstream at a position in the pulmonary artery, means (104) responsive to the first time-temperature concentration curve detected in the pulmonary artery for calculating a characteristic time for the first time-temperature concentration curve, means (28) for detecting a second time-temperature concentration curve of the bloodstream at a position in a systemic artery, means (104) responsive to the second time-temperature concentration curve detected in the systemic artery for calculating a characteristic time for the second time-temperature concentration curve, means (104) for calculating the now of blood through the heart and lungs, and means (104) for calculating a measure of extravascular lung water in accordance with the difference between the products of the blood flow times the first characteristic time and the blood now times the second characteristic time.
Abstract:
The present invention relates to a pneumatic sensor for detecting a breathing process, wherein said sensor comprises two rigid plates (1, 2) which are connected together along an edge (3), one at least of said plates being capable of rotation relative to the other. The plates are separated by a resilient member (6, 7) which is subject to deformation and has an inner volume filled with air and isolated from the environment. The inner volume of the member subject to deformation (6, 7) is further connected to a converter (10) for converting a pressure into an electric signal. This invention also relates to an apnoea monitoring unit that may include the above-mentioned pneumatic sensor. This monitoring unit comprises an amplifier for amplifying the signal from the pneumatic sensor as well as a comparator that generates pulses corresponding to a breathing process when the output signal from the amplifier exceeds an absolute value of the comparator threshold level. The amplification ratio of the amplifier and the threshold level of the comparator are automatically adjusted by a control unit according to the value of the output signal from said amplifier.
Abstract:
A nasal cavity patency tester (1) which tests the patency of the nasal cavity (C) of a subject, comprising a light transmitting member (85) having a first flat face (70) and a second face (71), transmitting light incident from the second face (71) and directing the transmitted light to the first face (70), a light source (16) which emits light directed to the second face (71) of the light transmitting member (85), an image pickup device (18) which picks up the image (I) of the exhale (B) through the nostrils of the subjects (P) blown over the first face (70), formed of water droplets (W), and an image processor (19) which processes the image (I) and finds nasal cavity patency information about at least one of the shape, area, change with time of the area, and coordinates of the distinctive end points of the image (I).
Abstract:
A method of treatment of tissue (136) with focussed ultrasound comprises placing adjacent the tissue (136) to be treated a reflector of ultrasound or an ultrasound energy conversion device (128) which converts received ultrasound energy to heat, stores the heat and then releases the heat over time into the tissue (136) to be treated. An ultrasound transducer (120) is then oriented with its focal point (142) adjacent the reflector or ultrasound energy conversion device (128). The tissue (136) is then irradiated with high intensity focussed ultrasound while the reflector or ultrasound energy conversion device (128) is in place.
Abstract:
A pressure sensor (18) is combined with a temperature sensor (14) to monitor a patient's breathing patterns. The combination of sensors (18, 14) enables an analysis of the patient's breathing patterns to be made without the use of a face mask even if the patient breathes through the mouth or draws only very weak breaths. The patient's sleep is therefore less likely to be disrupted by the presence of the monitoring equipment and a more accurate diagnosis of any sleep disorder can be made.