Midlatency somatosensory evoked potentials and explicit memory functions during recovery from propofol/sufentanil anaesthesia
© Current Science Ltd 1997
Published: 1 March 1997
Adequate anaesthesia and avoiding awareness in patients is of major concern for anaesthesiologists during anaesthesia. In a prospective study midlatency somatosensory evoked potentials (SEP) were investigated in relation to explicit memory function during recovery from propofol/sufentanil anaesthesia.
After approval of the local Ethics Committee and written informed consent 20 patients (43 ± 12 years, 71 ± 14 kg, ASA I-II) were included in the study. Anaesthesia was induced with 0.5 μg/kg sufentanil, 2 mg/kg propofol and 0.1 mg/kg vecuronium. After endotracheal intubation and normo-ventilation with FiO2 0.3 anaesthesia was maintained with 8 mg/kg/h propofol. SEPs were recorded at Erb, C6 and C4' (N20, P25, N35, P45, N50) following electrical stimulation of the median nerve (3 Hz, intensity of twofold motor threshold, 200/average, bandwidth 0.02–2 kHz). SEP recordings were performed the day before surgery (AWAKE) and during recovery from anaesthesia, until patients were able to identify a shown object (RECOVERY). Monitoring included HR, MAP, PetCO2, SaO2, arm and body temperature. The day after surgery patients were interviewed about their memory of the recovery period and classified into two groups: group 1, no memory; group 2, memory for recovery period. Statistics: Student t-test with P < 0.05 significant.