A Study of Clinical Monitoring for Psycosedative Levels by Electrophysiological Method

1997 Fiscal Year Final Research Report Summary

• Project/Area Number: 08672345
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Surgical dentistry
• Research Institution: Matsumoto Dental University
• Principal Investigator: HIROSE Isao Matsumoto Dental University, School of Dentistry, Professor, 歯学部, 教授 (70029982)
• Project Period (FY): 1996 – 1997
• Keywords: PARM / MONITORING / I.V.SEDATION / MIDAZOLUM

Research Abstract

Optimum levels of psycosedation are usually determined on the bases of the analysis of vital signs. We often experience differences in the sensitivity to sedative drugs among patients. To messure sedation levels more objectively by analyzing the relationship between sedation levels and changes in the posterior auricular muscle response (PAMR) which was messured electrophisiolosically. The subjects were 14 adult dental patients who gave informed consent to the test, and blood sampling. For sedation by intravenous midazolam injection, one or two milligrams midazolam were first administered. Additional 1 mg was given at intervals of 3 to 5 minutes until the optimum levels of sedation was achieved. PAMR was messured 3 minutes after each dose of midazolam. Plasma midazolam levels were messured by gas chromatography. An NEC-Sanei 7s12 signal processor was used for messuring PAMR. PAMR is easy to record. However, its amplitude varied greatly among individuals. For this reason, it was analyzed percent changes in the amplitude relative to its control value during the couse of sedation. The results were as follows; 1) the decrease of PAMR amplitudes were well correlated to sedation levels, and reduced to 19.7 ± 6.9% (at 193.0 ± 11.0ng in serum midazolam) of the control value on average at clinical optimum sedation levels. 2) Both the latency and inter-peak latency were significantly prolonged. PARM was found to be useful in assessing the depth of sedation in conscious individuals.