Measurement of central somatosensory conduction time in patients undergoing cardiopulmonary bypass: An index of neurologic function

Abstract

It is feasible to monitor somatosensory evoked potentials and central somatosensory conduction times during open heart surgery and cardiopulmonary bypass with moderate or profound hypothermia. Central conduction times are reproducible, have acceptably low interpatient and intrapatient variability, and are not significantly affected by fentanyl-induced anesthesia. There is a predictable logarithmic relationship between central conduction times and temperature with the central conduction time increasing by 6.6 percent for a 1 degree C decrease in temperature. These data indicate that somatosensory conduction times may be a useful index of central nervous system integrity during open heart surgery that utilizes cardiopulmonary bypass and hypothermia.