Brain-stem monitoring. I. A system for high-rate sequential BAEP recording and feature extraction.

A computerized system is proposed for the continuous automatic monitoring of BAEPs in the intensive care unit or in the operating room. A new adaptive optimal digital filtering technique has been developed to allow BAEP recording with 200-400 stimulations, i.e., within 10-20 sec only, every 2 min. This method permits a selective cancellation of the major artifacts as soon as they occur: electrical interference and myogenic activities which are commonly encountered in such environments. An algorithm for automatic peak detection (waves I-V) has been implemented, and the whole system has been evaluated in terms of reduction of the intra-individual variability of latencies and amplitudes. Some clinical examples of comatose patient monitoring are briefly presented to illustrate the performance and the reliability of the system.