Abstract: A body fat measurement device includes: hand electrodes that make contact with both hands; back area electrodes that makes contact with the surface of the back area side of the trunk area; foot electrodes that make contact with both feet; a body impedance measurement unit that measures a body impedance in a body using these multiple electrodes; and a body fat mass calculation unit that calculates a body fat mass based on the body impedance measured by the body impedance measurement unit. The foot electrodes that make contact with both feet are provided on a platform unit in an exposed state, and the hand electrodes that make contact with both hands and the back area electrodes that make contact with the surface of the back area side of the trunk area are all provided on a fitting unit in an exposed state.

Abstract: A medical electrical lead electrode assembly includes an insulative carrier and at least one conductive component. The at least one conductive component includes an electrode portion disposed on a first side of the carrier and at least one tab extending away from the electrode portion, through the carrier to a second side of the carrier. The electrode portion of the at least one component includes an outward facing contact surface and an inward facing surface, the inward facing surface being disposed opposite the contact surface and against a surface of the first side of the carrier. The electrode assembly further includes a joint coupling a flexible elongate conductor to the tab of the at least one component on the second side of the carrier, and an insulative layer extending over the joint and the tab and the conductor, the insulative layer being bonded to the second side of the carrier.

Abstract: A biosensor is described which can obtain physiological data from an individual. The biosensor may collect electrodermal activity, skin temperature, and other information. The biosensor may be attached to the body through the use of a garment which may be fastened in multiple locations on the human body. The biosensor includes compensation for electrodermal activity measurements based on the amount of pressure applied to the electrodes that are in contact with the skin. As pressure is increased the electrodermal activity values typically increase. By compensating for the influence that pressure changes have on electrodermal activity, more accurate analysis of physiology and therefore mental state analysis may be performed.

Abstract: A sensor device for detecting a change fluid level within body tissue comprising a housing with bridge segments connecting at intersections arranged to circumscribe an opening. Further, antenna elements are partially seated within the housing at intersections of bridge segments, comprise a generally planar antenna mounted to a substrate material at a base of the planar antenna, and an electrical shield surrounding the substrate. Also, an outer surface of the planar antenna faces away from the substrate. The antenna elements comprise at least first and second antenna element pairs having transmitting and receiving antenna elements and a bridging segment. A high sensitivity zone is formed between the transmitting antenna and receiving antenna. The antenna element pairs are spaced to create an area of reduced sensitivity between the high sensitivity zones, and the space is set so that the sensor is insensitive to fluid changes of a predetermined volume.

Abstract: An active dry sensor module for measurement of bioelectricity is disclosed. The active dry sensor module of the present invention excludes the use of a conductive gel, thereby not supplying unpleasantness and discomfort to a reagent and preventing the interference of the signal due to a noise component. Further, the active dry sensor module of the present invention amplifies the biomedical signal to a desired level, thereby precisely and easily measuring the biomedical signal.

Abstract: A device for determining muscle condition of a region of tissue. The device comprises an electrical impedance myography (EIM) portable probe bearing an electrode array. The electrode array comprises excitation electrodes used to apply multi-frequency electrical signals to the region of tissue and pickup electrodes that are used to collect electrical signals resulting from the application of the multi-frequency electrical signals to the region of tissue. To improve accuracy and reproducibility of EIM measurements, the electrode array is reconfigurable to select different subsets of excitation and pickup electrodes so that the electrodes are oriented differently with respect to muscle fibers. Additional devices may be associated with the EIM probe to measure such parameters as temperature, moisture content of the region, quality of contact of electrodes of the electrode array with a surface of the region and pressure with which the EEM probe is applied to the region.

Abstract: A patient monitoring device to be worn on a limb of a patient. Some embodiments of the patient monitoring device include at least one sensor assembly configured to detect a measurement indicating a distance around the patient's limb and a communications subassembly configured to transmit the measurement to at least one external computing device. Other embodiments of the patient monitoring device include at least one sensor assembly configured to detect a measurement indicating a distance around the patient's limb and at least one processor configured to detect whether the distance around the patient's limb has increased indicating edema. Some embodiments include an accelerometer configured to detect device orientation and/or patient activity information. The patient activity information may be analyzed by an external computing device and/or the patient monitoring device to determine whether the patient's activity level has declined indicating a medical problem.

Abstract: A sensor web device is provided for measuring EMG (electromyographic) signals. The device has a base sheet and a plurality of EMG sensors disposed on the base sheet. The plurality of EMG sensors are arranged so that a desired EMG signal of a muscle in a human body is obtained by a corresponding one of the plurality of EMG sensors.

Abstract: A “Wearable Electromyography-Based Controller” includes a plurality of Electromyography (EMG) sensors and provides a wired or wireless human-computer interface (HCl) for interacting with computing systems and attached devices via electrical signals generated by specific movement of the user's muscles. Following initial automated self-calibration and positional localization processes, measurement and interpretation of muscle generated electrical signals is accomplished by sampling signals from the EMG sensors of the Wearable Electromyography-Based Controller. In operation, the Wearable Electromyography-Based Controller is donned by the user and placed into a coarsely approximate position on the surface of the user's skin. Automated cues or instructions are then provided to the user for fine-tuning placement of the Wearable Electromyography-Based Controller.

Abstract: Apparatus comprising a housing; stimulation means mounted to the housing; a biosensor releasably mounted to the housing, the biosensor comprising a plurality of electrodes for detecting a sural nerve response evoked by the stimulation means; acquisition means mounted to the housing and electrically connected to the biosensor for acquiring the sural nerve response; processing means mounted to the housing and electrically connected to the acquisition means for digitizing, processing and storing the acquired sural nerve response; calculation means mounted to the housing and electrically connected to the processing means for calculating the conduction velocity and amplitude of the processed sural nerve response; and display means mounted to the housing for displaying the sural nerve conduction velocity and amplitude; wherein the stimulation means and the biosensor are designed to be placed on a patient's anatomy, in the vicinity of a sural nerve, by manipulating the housing.

Abstract: A textile structure for detecting body surface electrical signals of human is provided. The textile structure includes a non-conductive textile, a conductive textile, and a plurality of test terminals. The non-conductive textile covers the human body. The conductive textile has a first region, a second region, and a third region. The first region is interdigitated into but not electrically coupled to the third region. The first to third test terminals are respectively coupled to the first to third regions of the conductive textile. The first and second test terminals are used for detecting ECG signals. The first and third test terminals are used for detecting respiratory signals.

Abstract: An apparatus for muscle activation includes least one electrode adapted to deliver a neuromuscular stimulation (NMES) signal to a body portion. A controller provides a NMES signal comprising a sequence of stimulation signals to the electrode. A mechanical motion element coupled to the body portion and a mirror body portion is operatively coupled to the controller. The controller controls the NMES signal in conjunction with the mechanical motion element.

Abstract: A portable electrocardiograph, characterized in that a clamping cover which tends to close automatically is provided on one end of a housing; a finger hole is provided between the clamping cover and the housing; a lower half of the inner wall of the finger hole is defined on the housing; an upper half of the inner wall of the finger hole is provided on the clamping cover; the lower half of the inner wall is provided with a first electrode; the other end of the housing is provided with a second electrode; and the back face of the housing is provided with a third electrode, in which the first electrode or the third electrode is a neutral electrode. According to the present invention, at least one portion of at least one of the middle finger, the so-called ring finger, and the little finger of the user's hand for grasping the electrocardiograph can contact the neutral electrode, such that the error of the measured result caused by electrical potential fluctuation on the measured person's body can be eliminated.

Abstract: The present disclosure relates to methods, apparatus and sensor for measurement of cardiovascular quantities. In particular, a method for determining one or more cardiovascular quantities is disclosed, the method comprising determining the distension of a vessel enclosed by tissue having a skin surface, wherein determining the distension is based on a first sensor signal indicating capacitance variations between a first electrode and a second electrode; determining the vascular stiffness of the vessel; and determining the blood pressure based on the distension and the vascular stiffness of the vessel.

Abstract: A stretchable electrode for use in physiologic measurements on a human body, such as peripheral impedance plethysmography, is disclosed. One embodiment of the stretchable electrode comprises an uninsulated stainless steel wire braid formed into a tubular conductor surrounding an elastic core and attached to an elastic substrate or base. Other embodiments of the stretchable electrode include a garter spring, a flat braided or woven conductor and an undulating wire. The electrode is placed about a limb of a human body and elastically stretched so that the conductor is in substantially continuous circumferential electrical contact with the skin of the limb. A method of attaching the stretchable electrode to the limb of a human body is also disclosed.

Abstract: What is described are a signal detecting device for detecting a vital parameter of a living being, having a plurality of electrodes and an electrode selecting device for selecting a pair of electrodes from the plurality of electrodes such that a difference signal suitable for measuring the vital parameter is derivable, an electrode arrangement and a method.

Abstract: In a system and method for peripheral impedance plethysmography, an electrode for application to the patient's limb includes two outer current electrodes and two inner voltage electrodes. A distance between the two inner electrodes is automatically input into an analyzing device, either as a pre-stored value or as determined automatically from the electrode. Peripheral blood flow is calculated in accordance with that distance.

Abstract: This invention relates to the detection of bioelectric signals indicative of neuromuscular function. A mapping biosensor array is first used to identify, relative to reliable anatomical landmarks, the optimal myoelectrical detection site for the majority of the population. Then a diagnostic biosensor array is fabricated using this information so that when the diagnostic biosensor array is positioned on an individual using the reliable anatomical landmarks, the detection electrode is automatically positioned over the optimal detection site.

Abstract: Ultrasound Doppler probe 2 is placed above the vein downstream of the infusion site. Processor 4 converts the output from the probe 2 into a form that may be displayed as an image on display unit 5. It also determines whether the velocity corresponds to a flow of contrast medium along the vein. If the cannula 13 is properly sited and the contrast medium flows as desired along the vein, this will lead to an increased flow velocity in the vein. This is detected by ultrasound probe 2 and, as described above, the processor unit 4 will therefore determine that no extravasation has occurred. However, where extravasation of contrast medium occurs this results in a low or zero velocity output from the probe 2 from which the processor unit 4 determines that extravasation has occurred. It therefore immediately sends a “stop” signal to pump controller 11 which stops pump 10.

Abstract: The present invention relates to a method for recognizing and measuring heartbeat in physical training, in which method individual heartbeats are recognized and measured from the electrical signal of the heart, the EKG signal, on the area of waist and/or on the body area below the waist by means of two or more electrodes (2, 3) integrated to an outfit (1) or to a part of an outfit, and/or by means of two or more electrodes integrated to one or several wearable sensors, and for calculating various quantities describing the function of the heart. In the method in accordance with the invention, for recognizing and measuring heartbeat, the signals received from the heart are processed and examined with two or more different ways for improving the reliability of calculation and for decreasing the impact of noises.

Abstract: A workability evaluating apparatus comprises a myoelectric potential detecting unit, a signal processing unit, an arithmetic operation unit, and an output unit. The myoelectric potential detecting unit detects time-series fluctuations in myoelectric potentials of at least one pair of muscles, which show antagonistic activities while operating equipment among muscles of an operator used to operate the equipment, as myoelectric potential signals. The signal processing unit processes the detected myoelectric potentials. The arithmetic operation unit calculates time-series data of a first correlation coefficient in a specified sampling time between signals obtained by processing the myoelectric potential signals from the pair of antagonistic muscles, and performs evaluation of workability in operating the equipment by using the calculated time-series data. The output unit outputs a result of the performed evaluation.

Abstract: An apparatus and method for detecting physiological function, for example, nerve conduction, is described. In one embodiment the apparatus includes a housing including a stimulator shaped to fit a first anatomical site and a detector shaped to fit a second anatomical site. The housing automatically positions the detector substantially adjacent to the second anatomical site when the stimulator is positioned substantially adjacent to the first anatomical site. The detector contains a plurality of individual detection elements, whereby the response evoked by stimulation at the first anatomical site is measured using one or more of these detection elements at the second anatomical location.

Abstract: A system and method for determining smooth muscle motor activity in body organs. The system comprises electrodes for recording an analog signal in the subject's body, an analog to digital converter that converts the analog signal to a digital signal and a processor. Processing the digital signal includes obtaining power spectra of the digital signal, and identifying one or more frequency peaks in the power spectra. A peak in the power spectrum is identified within a frequency range in which an organ generates slow waves. The energy of the identified frequency peak is measured and an energy above a characteristic threshold is indicative of smooth muscle motor muscle motor activity in the respective organ.

Abstract: Tissue sensors house one or more sensor elements. Each element has a housing mounted substrate and a superstrate with a planar antenna between. A transitional periphery (TP) of a superstrate outer surface interconnects a base to a plateau. At least some of the TP has a generally smooth transition. Plural elements are spaced by the housing. Alternately, the superstrate TP is flat, the housing extends to the outer superstrate surface and a shield surrounds the element. The housing is flush with or recessed below the superstrate and defines a TP between the housing and superstrate. A method converts a reference signal to complex form; plots it in a complex plane as a reference point (RP); converts a measurement signal to complex form; plots it in the complex plane as a measurement point (MP); determine a complex distance between the MP and the RP; and compares complex distance to a threshold.

Abstract: An electric diagnostic tape measure used to measure the electrical conduction of a peripheral nerve using a standard electrical nerve stimulator. The tape measure includes a flexible, elongated body with an active recording electrode mounted or attached to its distal end. Formed on the lower surface of the active recording electrode is a conductive, adhesive layer that temporarily holds the electrode on the patient's skin during a test. Located on the top surface of the elongated body is a distance-measuring index. During a test, the elongated body is aligned so that the end of the distance-measuring index is aligned and registered with the active recording electrode. By moving the nerve stimulator to different locations adjacent to the skin adjacent to the elongated body, the distance of the nerve being tested may be measured. In one embodiment, a wire extends through the elongated body.

Abstract: A portable electrocardiograph, characterized in that a clamping cover which tends to close automatically is provided on one end of a housing; a finger hole is provided between the clamping cover and the housing; a lower half of the inner wall of the finger hole is defined on the housing; an upper half of the inner wall of the finger hole is provided on the clamping cover; the lower half of the inner wall is provided with a first electrode; the other end of the housing is provided with a second electrode; and the back face of the housing is provided with a third electrode, in which the first electrode or the third electrode is a neutral electrode. According to the present invention, at least one portion of at least one of the middle finger, the so-called ring finger, and the little finger of the user's hand for grasping the electrocardiograph can contact the neutral electrode, such that the error of the measured result caused by electrical potential fluctuation on the measured person's body can be eliminated.

Abstract: The present disclosure relates to dressings, such as patches and bandages, and other devices and systems that deliver nitric oxide.

Abstract: The methods and devices of a multi-functional operating interface for a care-taking machine. The multi-functional operating interface of the care-taking machine includes: muscle stretch sensor, multiplexer amplifying wave filter, analog-to-digital signal converter, image processing unit, and muscle pattern database and control bus. Aided by the present muscle template training method and potential image data collecting and processing method, it can become an interface that offers the user of a care-taking machine instantaneous and unlimited controllability of the machine, enabling such people, either sick or handicapped, to enjoy more convenience and better life.

Abstract: A nerve stimulator measuring device used to measure the length of electrical conduction of a nerve using a standard electrical nerve stimulator. The device includes an outer housing attached or integrally formed on the cathode probe on the standard nerve stimulator. Mounted on the two probes or located inside the outer housing is a retractable, flexible tape measure with length measure units printed thereon. During assembly, the outer housing is positioned over the two probes so that the tape measure disposed therebetween. During use, the end point of the tape is positioned over the recording sensor. The nerve stimulator is then pulled towards the hand so that the tape unwinds to the display the desired distance. The nerve stimulator is then held so that the cathode probe is pressed against the skin over the nerve and adjacent to the desired distance shown on the tape. The nerve stimulator is then activated and a reading is obtained.

Abstract: Methods and apparatus for non-invasively assessing physiological hard of soft tissue of human and other species are described. In a preferred embodiment, tissue is vibrationally stimulated in vivo through a frequency spectrum. The tissue reacts against the stimulus and the reaction is preferably measured and recorded. Based on analytical algorithms or comparisons with previously taken measurements, changes within the tissue can be detected and used for diagnostic purposes. Further embodiments describe the usage of the device and methods for in vivo intra-operative and post-operative implant evaluations and as a therapeutic tool.

Abstract: A hand and digit immobilizer is disclosed for preventing a patient from dislodging a pulse oximeter finger sensor by finger movement or fist clenching. In one form, the hand and digit immobilizer includes a glove body having a palm section and a back section defining a proximal opening for receiving a person's hand. The glove body has four finger base openings for receiving the fingers of the hand and has a thumb base opening for receiving the thumb. A finger covering section is connected to and extends away from each finger base opening. At least one finger covering section having a distal finger opening at its distal end. A rigid plate is secured to the palm section of the glove body and a palm side of each finger covering section such that clenching of the fingers is prevented thereby avoiding dislodging of a finger sensor from a fingertip.

Abstract: A monitoring system (800) is operative for receiving sensor signals and analyzing the sensor signals to identify events or conditions of interest, such as colic, with respect to a monitored animal. The sensors may be animal-borne sensors such as motion related sensors. The system (800) includes a processor (802) operative to identify the conditions of interest based on a stored pattern database (806), threshold tables (808) and heuristic engines (812). Upon identification of a condition of interest, a human expert may be consulted and alerts may be generated as required.

Abstract: An electronic system includes a reader and a remotely powered and remotely interrogated sensor transponder. The sensor transponder includes a coil or an antenna, a switched reactance circuit, a processor, and a sensor. The sensor transponder receives power radiated from the reader to the coil or antenna. The sensor uses the power for sensing. The sensor transponder is capable of processing sensor data in the processor and transmitting the sensor data to the reader using the switched reactance circuit. In one embodiment, the receiver coil or antenna is part of a resonant tank circuit which includes an impedance matching circuit. The impedance matching circuit is connected to the receiver coil or antenna to provide greater current to the sensor or other power-using device than would be available to the sensor or other power-using device if the sensor or other power-using device were connected between the first and second end. The impedance matching circuit can be two or more taps to the coil or antenna.

Abstract: An apparatus for detecting dislodgement of a needle inserted into a patient includes a sensor for detecting wetness due to blood and a sensor holder to secure the sensor to the patient such that the sensor detects wetness due to blood loss from the patient upon dislodgement of the needle. Methods and apparatuses for detecting, monitoring and/or controlling blood loss from a patient due to needle dislodgement are also provided.

Abstract: A method and apparatus for enabling the non-invasive acquisition of physiological parameters of a mammal, while allowing the mammal to move around a predetermined area is provided. In accordance with one example embodiment, a monitoring device for non-invasively acquiring physiological measurements of a mammal is provided. The device includes a first electrode configured to attach to an ear of the mammal in a manner suitable for obtaining a first electrical signal. A second electrode is configured to attach to a first alternate location of the mammal in a manner suitable for obtaining a second electrical signal. A third electrode is configured to attach to a second alternate location of the mammal in a manner suitable for obtaining a third electrical signal. The first electrode, second electrode, and third electrode are in communication with a signal receiver. Physiological parameters, such as those associated with electrocardiograms, can be obtained using the monitoring device.

Abstract: A portable apparatus which allows a user to perform self-diagnostic evaluation of nerve sensory latency between a pair of epidermal locations proximal to nerve conduction paths. The device provides a simple and low-cost self-diagnostic apparatus which may be used for the detection and ongoing monitoring of sensory latency, such as sensory latency which is the result of carpal tunnel syndrome. The apparatus is powered by a single battery which provides power to all circuitry of the apparatus. Upon power activation, the device generates a series of high voltage stimulus pulses at an electrode in epidermal contact with the user/operator. The nerve response voltage is detected by a second electrode located along nerve pathway and the time delay between stimulus and response is displayed and periodically updated as each new response is detected.

Abstract: A measuring system for measuring physiological parameters comprises a garment in the form of a sleeve or glove, or combination sleeve and glove, having a series of sensors and a control unit incorporated therewith. The control unit sleeve or glove and a sling in combination with the measurement of numerous physiological parameters by effecting accurate placement of the sensors on a patient's body.

Abstract: An assembly that incorporates an expandable strap for use in electrical impedance tomography includes a strap adapted to be mounted onto the body of a patient. A plurality of electrodes is mounted on the strap and spaced equidistantly along the length of the strap. An electrical connector is mounted on the strap, and electrical traces extend from each electrode to the connector. Preferably, the strap is made of a substantially inelastic material. In one embodiment, the strap has a serpentine shape to allow for uniform expansion.

Abstract: The hematocrit of blood (i.e., the percentage of whole blood volume occupied by red blood cells) perfusing a finger is determined by stimulating the finger with two current frequencies, one relatively high (e.g., 10 MHZ) and the other relatively low (e.g., 100 KHz). Voltages induced in the finger in response to the two current frequencies are then captured and separated into baseline and pulsatile components. The hematocrit is determined as a function of the ratio of the high frequency pulsatile component to the low frequency pulsatile component, multiplied by the ratio of the square of the low frequency baseline component to the square of the high frequency baseline component. The volume of blood perfusing the body part at which hematocrit is to be measured may be increased on each pulse by the application of external pressure to the finger, such as by applying a pressure cuff to the finger. Assemblages including two pairs of electrodes are used to effect the determination of hematocrit.

Abstract: An electrode structure for measuring an ECG signal on a person's skin. The electrode structure (100) to be arranged on the person's finger (102) comprises an inner surface (116) residing against the finger (102), which inner surface (116) of the electrode structure (100) comprises an inner surface electrode (118), the electrode structure (100) further comprising an outer surface (120) opposite to the inner surface (116), which outer surface (120) of the electrode structure (100) comprises an outer surface electrode (122) to be arranged against a point on the person's skin other than said finger (102) having the electrode structure (100) arranged thereon, the electrode structure being arranged to measure a potential difference caused by the ECG signal between a first electrode and a second electrode.

Abstract: Disclosed is a impedance measuring apparatus which is easy to use, and which is guaranteed to be free of incorrect measurement caused by some joints appearing in the current flowing passage intervening between two selected body parts and by the indefinite length between two selected body parts. The measuring apparatus of the present invention limits the place of the body under measurement to “one body region”, i.e.

Abstract: Apparatus for temporarily attaching a sensor of a physiological parameter to an extremity of a person. The apparatus includes a fabric structure configured to be positioned on an extremity of a person, the fabric structure advantageously formed of loops of yarn-like material which exhibit porosity and controlled elasticity; and sensor(s) of physiological parameters mounted on the fabric structure such that when the structure is positioned on the extremity of a person, the sensors sense physiological parameters of the person.

Abstract: A portable apparatus which allows a user to perform self-diagnostic evaluation of nerve sensory latency between a pair of epidermal locations proximal to nerve conduction paths. The device provides a simple and low-cost self-diagnostic apparatus which may be used for the detection and ongoing monitoring of sensory latency, such as sensory latency which is the result of carpal tunnel syndrome. The apparatus is powered by a single battery which provides power to all circuitry of the apparatus. Upon power activation, the device generates a series of high voltage stimulus pulses at an electrode in epidermal contact with the user/operator. The nerve response voltage is detected by a second electrode located along nerve pathway and the time delay between stimulus and response is displayed and periodically updated as each new response is detected.

Abstract: An apparatus for the detection of extravasation is positioned in a manner so that the vicinity of a site is available for palpation and is visible for visual inspection. Another embodiment of the apparatus improves the sensitivity of detection by positioning an energy source and a receiver between a first layer of a high dielectric material and a second lay of a low dielectric material. The apparatus may further include a third layer of a conductive material to shield the apparatus from stray capacitance. In addition, a system for detection of extravasation includes an array of sensors located at, adjacent to and/or remote from an injection site.

Abstract: A method and device for detecting extravasation employs a non-invasive sensor system deployed on the skin to identify changes in both subcutaneous interstitial fluid pressure and skin temperature. Preferably, the system monitors the sensor system outputs to identify a sequence of a skin temperature drop followed by a interstitial fluid pressure increase. This pattern is distinctive of the occurrence of extravasation, thereby providing very reliable detection. Most preferably, a simple sensor structure based upon multiple piezoelectric film sensors is used.

Abstract: A transcutaneous medical electrode for use with devices for introduce electrical signals into areas of the body or for receiving electrical signals from body areas. The electrode includes a flexible electrically conductive sheet having an electrically conductive adhesive layer on one surface. A female connector having an opening for receiving a conventional lead wire tip is secured to the opposite surface of the sheet. A sheathed male connector includes a tip for insertion into the female connector opening without exposing the tip to touching by the operator of the device or the patient. The female connector is preferably tubular with an approximately axial opening. The female connector may be secured to the sheet, parallel to the sheet, with the male connector receiving end extending beyond and edge of the sheet.

Abstract: An apparatus for the detection of extravasation is positioned in a manner so that the vicinity of a site is available for palpation and is visible for visual inspection. Another embodiment of the apparatus improves the sensitivity of detection by positioning an energy source and a receiver between a first layer of a high dielectric material and a second lay of a low dielectric material. The apparatus may further include a third layer of a conductive material to shield the apparatus from stray capacitance. In addition, a system for detection of extravasation includes an array of sensors located at, adjacent to and/or remote from an injection site.

Abstract: A medical extravasation device has an electrode patch that can attach to the skin for sensing electrical information. Tissue impedance is calculated from the electrode patch signals. The patch has elongate pick-up electrodes inboard of elongate energizing electrodes. The measuring zone determined by the elongate space between the pick-up electrodes enhances sensitivity and specificity. The presence of an extravasation is determined by interpreting the tissue impedance measurement. The method for determining the extravasation includes a first step of determining a pre-injection baseline measurement of the tissue impedance. Then, the tissue impedance is monitored during the procedure itself. A predetermined amount of change in tissue impedance is determined to indicate an extravasation.

Abstract: The technique for detecting extravasation during the injection of fluid into a patient involves the establishment of a baseline representing impedance at the zone of the injection prior to the injection starting. Extravasation is signaled when at least two characteristics appear. First is that the impedance varies from the baseline more than a predetermined amount in more than a predetermined number of discreet time slots called epochs herein. Second is that, the rate of change of the impedance, which is called the slope herein, is consistently greater than a predetermined amount.

Abstract: Body function measuring apparatus which provides: (1) an indication of the body function being measured, and (2) a loose probe condition by determining that the difference between the rate of change of a first body function signal, developed by a first sensor in the probe, and the rate of change of a second body function signal, developed by a second sensor in the probe, exceeds a predetermined threshold.