Electroencephalographic system for intra-operative open-heart surgery

Abstract

During open-heart surgery an EEG (electroencephalograph) system detects a patient's brain waves, amplifies the brain wave signals and converts them into digital data. The cardiopulmonary bypass pump (heart-lung machine) is connected to blood flow and blood temperature transducers whose measurements, in digital form, are used to calculate a standard of normal electro-physiological responses to blood flow and temperature changes with which the patient's actual brain wave responses will be compared. A visual display indicates to the surgical team, as to each of eight brain sectors, whether the patient's brain waves show that remedial action may be required. The digitalized brain wave signals, after processing to reduce muscle artifact and other noise, are displayed, in one embodiment, as intensity modulated time segments, using a moving window type of display in which the current segment is statistically compared to the group of immediate prior segments to provide a current self-norm (NORMS n). A new display (NORMS n+ 1) is started when a statistically meaningful different segment occurs and comparison is made and displayed between the two displays (NORMS n+ 1 and NORMS n). In another embodiment the same comparison of the groups is made, but the visual display utilizes a set of color-coded lights in the eight sectors of the display.

Dependencies are inferred from the claim text.