Instrumentarium Corporation

General Electric Company

Instrumentarium Oy

Ge Healthcare Finland Oy

Borje T Rantala

Kurt Peter Weckstrom

Lauri P Kankkunen

Timo Merilainen

Juha Virtanen

Matti VeliTapani Huiku

Pekka Tuomo Merilainen

Kai Karlsson

Hanna Elina Viertio-Oja

Mikko Kaski

Antti L Martikainen

Jan Petri Ekstrom

Markku Erik Spoof

Osmo Toikka

Hanna Elina Vierti&ouml;-Oja

Seppo Iikka Juhani Virtanen

Erno Muuranta

Olli Aaltonen

Raimo A Piskunen

Kari Makiniemi

A method for handling sudden and substantial pressure changes in invasive arterial blood pressure monitoring, a blood pressure monitoring apparatus, and a computer program product for a blood pressure monitoring apparatus are disclosed. To provide a user of a patient monitor a possibility to readily adapt the alarm functionality of blood pressure measurement to a clinical task without a need to go through a complicated nullifying process of a high priority alarm, a touchable user interface element is produced onto a touch screen of patient monitor if a sudden and substantial change is detected in measured arterial blood pressure of the subject. The user interface element is indicative of an alarm and configured to enable the user to modify alarm functionality of the patient monitor for an intentional clinical task that caused the sudden and substantial change in the measured arterial blood pressure.

Method for handling pressure changes in invasive blood pressure monitoring, apparatus for blood pressure monitoring, and computer program product for blood pressure monitoring apparatus

A method for controlling alarms in a physiological monitoring apparatus, a physiological monitoring apparatus, and a computer program product for a physiological monitoring apparatus are disclosed. In order to decrease the number of nuisance alarms, the level of a physiological signal obtained from a subject is observed and signal morphology is determined for the physiological signal in response to detecting a change of the level of the physiological signal to a predetermined value range representing low signal values, thereby to obtain reference morphology for the physiological signal. Signal morphology is monitored if the physiological signal remains in the predetermined value range and alarms are suppressed as long as the signal morphology fulfills predefined criteria with respect to the reference morphology and the level of the physiological signal remains in the predetermined value range.

Alarm control method, physiological monitoring apparatus, and computer program product for a physiological monitoring apparatus

A mechanism for authenticating a physiological sensor is disclosed. When a sensor is connected to a monitor, the monitor examines whether a first sensor-specific usage identifier of the connected sensor is consistent with a second sensor-specific usage identifier thereof. The first and second sensor-specific usage identifiers are indicative of the cumulative usage of the connected sensor, but may nevertheless be unequal. The first sensor-specific usage identifier is maintained in the sensor and the second sensor-specific usage identifier in a host memory external to the sensor. The use of the connected sensor is allowed when the examining indicates that the said two identifiers of the connected sensor are consistent, and rejected when the identifiers are inconsistent. The two identifiers are further updated in response to the use of the connected sensor in the patient monitor, thereby to keep the said identifiers consistent and updated for a subsequent use attempt of the sensor.

Method and computer program for authenticating a physiological sensor, a sensor system, a patient monitor, and a physiological sensor

A sensor interface configured to adapt analog and digital sensors is disclosed herein. The sensor interface unit includes: a port configured to be coupled to either a digital sensor or an analog sensor and a signal processing circuit for processing an analog sensor output when an analog sensor is coupled to the port. The interface further includes a switching mechanism configured to bypass the signal processing circuitry when a digital sensor is coupled to the port.

Sensor interface

The invention relates to a probe and a method for use with a probe, which produces signals indicative of the light absorption of arterial blood at least at a first light wave-length and at a second light wavelength. In order to indicate if the probe is not properly attached to a tissue site the method comprises measuring with at a third wave-length. The third wavelength is chosen so that human tissue is less transparent than at the first and second wavelengths.

Probe and a method for use with a probe

The invention relates to a method and apparatus for detecting artifacts in a bioelectric signal, especially in a frontal EEG signal. In order to accomplish an uncomplicated mechanism for detecting artifacts in clinical applications, an impedance signal is measured through a first electrode set attached to the skin surface in a measurement area of a patient's body, the impedance signal being indicative of the impedance of the signal path formed between individual electrodes of the set. Simultaneously with the impedance measurement, a bioelectric signal is acquired through a second electrode set also attached to the skin surface of the measurement area, and the time periods are determined during which the impedance signal fulfills at least one predetermined criterion indicative of the presence of artifact in the bioelectric signal. In one embodiment, the first and second electrode sets are formed by a common set of two electrodes.

Detection of artifacts in bioelectric signals

A method and apparatus for ascertaining the cerebral state of a patient. The method/apparatus may find use in ascertaining the depth of anesthesia of the patient. In one embodiment, the entropy of the patient's EEG signal data is determined as an indication of the cerebral state. A frequency domain power spectrum quantity is obtained from the patient's EMG signal data. The latter quantity can be updated more frequently than the EEG entropy due to its higher frequency. The EEG entropy indication and the EMG power spectrum indication can be combined into a composite indicator that provides an immediate indication of changes in the cerebral state of the patient. In another embodiment, the frequency range over which the entropy of the biopotential signal from the patient is determined is broadened to encompass both EEG signal data and EMG signal data and the entropy so determined used as an indication of the patient's cerebral state.

Method and apparatus for determining the cerebral state of a patient with fast response

The invention relates to pulse oximeters used to measure blood oxygenation. The current trend towards lower power consumption has brought a problem of erroneous readings caused by intrachannel crosstalk, i.e. errors due to the coupling of undesired capacitive, inductive, or conductive (resistive) pulse power from the emitting side of the pulse oximeter directly to the detecting side of the oximeter. The pulse oximeter of the invention is therefore provided with means for detecting whether intrachannel crosstalk is present and whether it will cause erroneous results in the oxygenation measurements. The pulse oximeter is preferably further provided with means for eliminating intrachannel crosstalk which are adapted to control the measurement so that measurement signals can be obtained which are substantially void of crosstalk components.

Pulse oximeter

An apparatus and a method for analyzing a compound to be drawn from a patient's organ. The apparatus comprises a sampling element having a wall which a compound to be analyzed is capable of penetrating. The apparatus also includes a pressure-difference producing element which, through the action of a pressure-difference, is capable of delivering a sample along a tube extending from the sampling element. The apparatus also includes an analyzer capable of performing an analysis on a sample drawn from the sampling element. The analyzer is in flow communication with the sampling element by way of the tube. According to the method, a mixture consisting of a medium and a compound drawn from the organ is delivered to the analyzer for a subsequent analysis, and at least some of the mixture is returned from the analyzer back to the sampling element.

Method and apparatus for analyzing a sample

Patient monitoring system for the monitoring of a patient's condition using monitoring parameters determined about the patient, said system comprising a central data processing unit (1), peripherals (2, 3, 4); parameter modules (5), each comprising a preamplifier (6) for preliminary amplification of a parameter signal, an A/D converter (7) for converting the parameter signal into digital form, and a first optic transmitter-receiver (8) for isolating the data transfer of the digital parameter signal; data transfer equipment for data communication between the first transmitter-receivers (8) of the parameter modules and the central data processing unit (1); a coupling frame (9), on which parameter modules (5) can be detachably mounted: parameter sensors (10) to be connected to the patient and a sensor cable (11) for each parameter sensor to pass the parameter signal from the parameter sensor to the preamplifier corresponding to the parameter concerned. The coupling frame (9) is made of a material substantially optically permeable to light to allow it to function as a medium for optic data communication. The data transfer equipment for communication between a first transmitter-receiver (8) and the central data processing unit (1) comprises a second optic transmitter-receiver (12) attached to the coupling frame (9) to achieve data communication together with the first transmitter-receivers using optic signals travelling inside the material of the coupling frame (9).

Patient monitoring system

The invention relates to a measuring instrument for detecting muscular activity (F) especially in the area of the hand. The measuring instrument (1) comprises an elongated connecting part (2), by which at least two points of the hand (6) moving with respect to one another are supported so that the movement of these points is transferred to the connecting part, a hand-securing means (12), and a measuring transducer (3, 13) secured to the connecting part for providing a signal dependent on the movement between the said points of the hand and preferably proportional to this movement, which signal can be transferred to the device (10) providing the measuring results. The connecting part (2) comprises two branches (4a and 4b) which together form an angle (5) and are connected to one another in an articulated (9) manner so that the angle (5) between the branches forms a plane (20) which remains at least approximately constant. The first branch (4a) is supported by one finger (7) and the second branch (4b) is supported by a part (8) of the hand with respect to which the said finger moves, in this case the forefinger. A force measuring transducer (3) is placed to measure the force respectively dominant between the branches.

Measuring instrument for detecting degrees of relaxation

A radiation source assembly for optical transducers used for the analysis of material components of media, whereby the radiation source assembly comprises: two thermal radiation sources (1, 2), of which the first radiation source (1) is located, in relation to the second radiation source, in such a position that it emits through the second radiation source (2); a band-stop filter (10) located between the first and the second radiation sources, so that the radiation (6) emitted by the first radiation source passes through it. Both thermal radiation sources (1, 2) comprise a substrate (3, 11) made of silicon, of a silicon mixture or of a silicon compound, and a recess (53) made in the substrate, and micro-filaments (4, 5), which are fastened at their ends to the outer surface (51, 52) of the substrate, their radiation (6, 8) emitting regions being at a distance (H) from the bottom surface (54) of the recess. The stop band of the band-stop filter (10) substantially corresponds to the absorption distribution of the material component of the medium to be analyzed with the transducer.

Double radiation source assembly and transducer

A method for calibrating a gas analyzer (1). A gas analyzer is calibrated by measuring the zero level of the analyzer (1). The level of the analyzer is measured, after a preceding reset, whenever a temperature variation (.DELTA.T) of an infrared sensor (14) included in the analyzer (1) or of a component thermally connected in a highly conductive manner thereto exceeds a predetermined threshold value (A), or the temperature variation rate (D) of the infrared sensor (14) of the analyzer (1) or of a component thermally connected in a highly conductive manner thereto exceeds a predetermined limit valve.

Method for calibrating the zero point in a gas analyzer

The invention relates to a method and apparatus for temperature compensation in gas analyzer equipment for transient error caused by temperature change. According to the method, a radiation source (1) is used for transmitting electromagnetic radiation through a gas mixture to be analyzed, the intensity of radiation transmitted through the gas mixture being analyzed is detected by means of a thermal detector (4) comprising a radiation detecting sensor element (16) and a reference sensor element (17) for generating an output signal proportional to the concentration of gas being analyzed, the temperature of said thermal detector (4) is measured either directly or indirectly, the measured detector temperature values are recorded as a function of time, and the output signal of the thermal detector (4) is temperature compensated by a correction term dependent on the temperature rate of change (DT) of the thermal detector. According to the invention, the uncorrected output signal V.sub.mass of the thermal detector (4) is temperature compensated by adding a correction term V.sub.comp dependent on the temperature rate of change (DT) of the thermal detector to said output signal.

Growing community of inventors

Helsinki, Finland

Borje T Rantala