초록 ▼

A patient monitoring system measures the concentration of a particular substance in a patient's tissue, blood, or other bodily fluids, provides an indication of the rate of change of such concentration, and determines whether the measured concentration and rate of change are within certain preset li

A patient monitoring system measures the concentration of a particular substance in a patient's tissue, blood, or other bodily fluids, provides an indication of the rate of change of such concentration, and determines whether the measured concentration and rate of change are within certain preset limits. If not, an audible and/or visual alarm signal is generated. The patient monitoring system includes at least one enzymatic sensor adapted to be inserted into the patient, where it produces sensor signals related to the concentration of the substance being measured. The sensor signals are delivered through a suitable interconnect cable to a monitor. In one embodiment, the interconnect cable includes a contactless connector that electrically isolates the enzymatic sensor from the monitor, and reduces the number of conductors required to interface with a plurality of sensors. The monitor interprets the sensor signals by applying a previously determined calibration to quantitatively determine the substance concentration value. The substance concentration value thus determined is then processed in order to determine the rate of change, is stored (to create a history or record), and may also be displayed in large, easy-to-read numerals. Rate of change information (trend) may also be numerically or graphically displayed.

대표청구항 ▼

[ What is claimed is:] [1.] A glucose monitoring system comprising:an enzymatic glucose sensor adapted to be placed within a person whose blood glucose concentration is to be measured, said glucose sensor including means for generating a sensor signal that varies inversely proportional to the concen

[ What is claimed is:] [1.] A glucose monitoring system comprising:an enzymatic glucose sensor adapted to be placed within a person whose blood glucose concentration is to be measured, said glucose sensor including means for generating a sensor signal that varies inversely proportional to the concentration of sensed glucose, said glucose sensor comprising an oxygen detector that detects the amount of oxygen in the region of a prescribed enzyme held within said glucose sensor, and wherein glucose and oxygen react with said prescribed enzyme such that the amount of oxygen is inversely proportional to the glucose concentration, and wherein said oxygen detector comprisesa first working electrode, a counter electrode, a reference electrode, and a second working electrode, all of said first and second working electrodes, reference electrode and counter electrode being enclosed within a first membrane wherein an ionic solution is maintained, and said first membrane being enclosed within a second membrane,said prescribed enzyme being confined to a window region near said first working electrode,electrical means for causing an electrical current to flow between said counter electrode and said first and second working electrodes, andmeans for measuring how much current flows from said first and second working electrodes when a prescribed trim voltage is maintained across said reference electrode and said first and second working electrodes;sensor signal comprises the ratio of said currents, thereby providing a measure of oxygen in the vicinity of said glucose sensor; anda glucose monitor electrically coupled to the glucose sensor, said monitor comprisingmeans for receiving the sensor signal from the signal generating means,means for processing the sensor signal and generating a glucose concentration data signal therefrom,means for storing the glucose concentration data signal,means for monitoring the glucose concentration data signal over a prescribed period of time and generating a rate of change signal that indicates how rapidly the glucose concentration data signal is changing,means for selectively displaying the glucose concentration data signal and the rate of change signal,first alarm means for determining if the glucose concentration data signal exceeds a preset level limit, and if so, generating a first alarm signal,second alarm means for determining if the rate of change signal exceeds a preset trend limit, and if so, generating a second alarm signal,calibration means for periodically calibrating the sensor so that it provides an accurate measure of the glucose concentration in the blood stream, andcontrol means for controlling the monitor so that it performs at least one of a plurality of monitoring functions as selected by a user of said monitor.