Abstract:
A fetal pulse oximeter sensor (22, 24) is mounted on a sensor head (10) with articulating means comprising a cable (26) or rod, lodged in a lumen (36) on one side of the sensor to either push or pull that side of the sensor with respect to the main body, thus causing the sensor head to articulate. By using the articulating mechanism, the sensor head can be applied with pressure against the fetus' scalp, until an adhesive (34) takes hold, preferably an adhesive which is appropriate for the wet surface. The adhesive has sufficient adhering properties to maintain the sensor in place, without requiring suction, while at the same time does not damage the fetus' skin upon removal.
Abstract:
The oxygen generation compositions are tin fueled to produce a significantly lower carbon monoxide contamination of the breathable oxygen generated. The oxygen generating compositions comprise about 0.5-15 % by weight of tin powder as a fuel and rheology modifier; from zero to about 15 % by weight of a transition metal oxide catalyst; about 0.1-5 % by weight of an alkaline compound as a chlorine remover and reaction rate modifier; and the remainder of an oxygen source selected from the group consisting of alkali metal chlorates, alkali metal perchlorates, and mixtures thereof. The oxygen generating composition can optionally further include up to about 5 % of a binder. The oxygen generating compositions have a smoother, more uniform rate of oxygen generation, lower temperature sensitivity, and a lower operating temperature than comparable chlorate/perchlorate oxygen generation compositions utilizing iron powder as a fuel.
Abstract:
A blower (14) pressurizes the system with fresh air, conduit (16) ducts such pressurized air to a standard nasal mask (18) which is fitted about the nose or a nasal pillow that is fitted to the nose and extends directly into the patient's nares. Port (19) continuously vents a small amount of air from the nasal mask or pillow in order to prevent moisture buildup and subsequent condensation therein. The port also prevents buildup of exhaled gases including CO2. The actual pressure within the system is controlled by relief valve (20) which vents superfluous air volume to the atmosphere. The position of the relief valve is in turn controlled by controller (24) pursuant to a number of different signals. Flow meter (26) provides information as to the volume of air inhaled by the patient, while pressure sensor (28) provides information as to the pressurization of the system at any given moment. The function of the controller is additionally subject to various parameters that are input such as through keyboard (30). The controller is also operative to control the position of valve (21) which is closed when relief valve (20) is opened and to tailor the output of blower (14) in relation to pressure demands. The system (12) monitors the tidal volume of each cycle and more particularly the sum of the tidal volumes over a given period of time to calculate the minute volume. The calculated value is compared with a target to determine whether an insufficient or an excessive volume of air is being respirated. In the event the actual minute volume exceeds the target value, the IPAP is gradually reduced such as by a small increment every few minutes. If, on the other hand, the actual minute volume is less than the target value, the IPAP is gradually increased, again by a small increment every few minutes.
Abstract:
A presenting part fetal pulse oximeter sensor which does not penetrate the fetus' skin, and does not rely on a vacuum for attachment is provided. The fetal sensor (10) of the present invention is held in place by pressure applied to the fetus by a number of different mechanisms. In one embodiment, the sensor is held in place against the fetus by a rigid rod (12), with the pressure being applied by the physician or technican's hand on the rod. This type of sensor is useful for spot-checking, where continuous monitoring is not needed. In another embodiment, a pre-loaded spring (24) is coupled between the rod and the sensor head to prevent too much pressure being applied by the user.
Abstract:
A fetal pulse oximeter sensor in which a sensor head (10) is held against the fetus (14) by the action of a securing means (20, 24) which is remote from the sensor head. The securing means is sufficiently remote so that light detected by the light detector (48) in the sensor head does not scatter through tissue which may be deformed by the securing mechanism. The securing mechanism could deform the tissue by applying pressure, to exanguinate the tissue, or could attach to the tissue by vacuum, penetration, or glue, etc.
Abstract:
An improved infant/neonatal pulse oximeter sensor substrate which is preferably conforming to the shape of the infant or neonate's foot. In one embodiment, the pad (10) conforms to the heel of the infant, with the emitter (14) and detector (20) preferably being mounted in the region of the calcaneus bone (26). The heel pad can be held in place with a stretchable sock (52). In an alternate embodiment, the conformable pad is a sock (52) with recesses or pockets (54, 56) cut in it for holding the emitter (14) and detector (20).
Abstract:
An improved electromagnetic shield for a photodetector which uses a wire mesh screen laminated to an insulating layer. A portion of the wire mesh screen and laminated layer sandwich can then be cut out to provide an individual electromagnetic shield. The sandwich combination (24) is flexible, and can be easily wrapped around the photodetector (26). Preferably, an adhesive is on one side of the insulating layer, to allow the wrapped combination to adhere to the photodetector.
Abstract:
A heat exchanger strip (19) which can be incorporated into a heat and moisture exchanger (10). The heat exchanger strip (19) includes an elongate polymer film having a longitudinal axis, a front and a back surface and a first and second edge (27, 29) generally parallel to the longitudinal axis of the strip (19). A plurality of elongate curved spacers (24) are connected to the polymer film. Each spacer (24) can include a curved longitudinal axis and first and second edges (27, 29) disposed on opposite sides of the longitudinal axis of each spacer (24). The edges (27, 29) are generally parallel to the longitudinal axis of the spacer (24). Spacers (24) can be connected to the front surface of the film such that the spacer's longitudinal axes extend generally parallel to each other between the first edge (27) of the strip (19) and the second edge (29) of the strip (19) to define three sides of a curved rectangular flow channel (28). The heat exchanger strip (19) can be disposed in a spiraling, generally cylindrically spaced roll such the heat exchanger strip (19) is arranged in generally concentric layers with the back surface of the polymer film defining a fourth side of the flow channel (28).
Abstract:
An apparatus (10) is provided for controlling discharge of oxygen from an oxygen supply source (12) to a patient. The apparatus includes an oxygen supply inlet (47), a pressure regulator (14) coupled to the oxygen supply inlet and configured to reduce pressure of oxygen received from the oxygen supply inlet to a selected magnitude, a flow controller (16) coupled to the pressure regulator (14) and configured to meter oxygen received from the pressure regulator at a selected flow rate, and an oxygen distribution assembly including a pneumatic demand oxygen valve (18) and a conduit (51) conducting oxygen discharged from the flow controller through the pressure regulator to the pneumatic demand oxygen valve for delivery to a patient. The flow controller (16) includes a chamber (110) and a rotary valve (112) for splitting oxygen discharged from chamber (110) into a first stream in an oxygen supply passageway (51) for use by a patient and a second stream in a diaphragm supply passageway (48) for controlling operation of pneumatic demand oxygen valve.
Abstract:
Motion compensation is based on analysis of intensity signals received by detectors, without separately measuring a motion signal, without providing feedback to cancel the motion signal and without attempting to mathematically eliminate the motion signal. Instead, the present invention mathematically recognizes the presence of the motion signal and recognizes a few key characteristics of the motion signal and makes corresponding assumptions. First, it is recognized that the motion/noise in each wavelength signal is proportional. Second, it is assumed that the blood pulse signal is not affected by motion.