Patent ID: 6487428
Filing Date: 2002-11-26
Classification: A61B

Abstract:
Extravasation detection apparatus comprising:a support pad adapted for attachment to a body part of a patient in proximity to a site at which a fluid is to be injected into the patient; a plurality of light sources, mounted to said support pad, for radiating light into the body part; means for energizing said light sources in an encoded manner to radiate light into the body part in an encoded manner; a plurality of light detectors, mounted to said support pad, for: (a) individually detecting light transmitted from said light sources that is reflected, scattered, diffused or otherwise emitted from the body part, and (b) individually developing light source/light detector pair signals representative of the light detected individually by said light detectors; means for developing, prior to injection of the fluid into the body part, a plurality of individual light source/light detector pair baseline signals associated with each light source/light detector pair and against which measurements made during injection of the fluid into the body part are compared; means for comparing the light source/light detector pair signals with the associated light source/light detector pair baseline signals; means for developing from the comparisons of the light source/light detector pair signals with the associated light source/light detector pair baseline signals new light source/light detector pair signals having an improved signal-to-noise ratio; means for developing, prior to injection of the fluid into the body part, a model, dependent on the arrangement of said light sources and said light detectors on said support pad, for calculating extravasation volume from the new light source/light detector pair signals having an improved signal-to-noise ratio; means for combining, according to the extravasation model, the new light source/light detector signals having an improved signal-to-noise ratio to determine the volume of extravasation; and means for comparing the volume of extravasation with a prescribed level of extravasation.