[Clinical study on applying brainstem auditory evoked potential to monitor anesthesia depth and awaken in children].

OBJECTIVES: To study applying auditory brainstem reaction (ABR) to monitor the general anesthesia depth and awaken degree in children as an objective guide. METHODS: Forty-five infant or children patients, American Society of Anesthesiologists(ASA) graded I-II, with normal audition, were selected and divided into 3 groups (15 cases per group) to receive propofal venous anesthesia, fentanyl venous anesthesia, or isoflurane anesthesia, respectively. During anesthesia, peak latencies (PL) of I, III, V wave, and interpeak latencies (IPL) of I-III, III-V, I-V were monitored and recorded after short sound stimulation of 90 db which accumulated 1,000 times with Madsen. The changing of PL and IPL with time passing and anesthesia dosage was studied to discuss the feature of ABR in each anesthesia procedure as above. RESULTS: There is a significant positive correlation between PL and IPL of ABR waves as above and the dosage of propofol or the concentration of isoflurane. The dosage or the concentration increased, and PL and IPL prolonged. It is important of PL of wave I to reflect anesthesia degree. It is wave V with the best stability and correlation to monitor anesthesia degree. After anesthesia period or patients almost awaken, PL and IPL of some ABR waves were still more than normal values, which is detention reaction. For the fentanyl anesthesia, ABR is not sensible enough, i.e. has little correlation. CONCLUSION: The changing of PL and IPL of ABR waves could conclude anesthesia degree in children and be treated as reference of whether awaken or not in some certain, but have possibility of detention reaction.