The Clinical Investigation About The Target-contolled Infusing Propofol Or Midazolam And Bispectral Index Applied To Sedation For Patients In ICU

Objective TCI (Target-contolled Infusion, TCI) and BIS (Bispectral Index, BIS) is the great advance in the field of total intravenous anaesthesia and the monitoring of the depth of anaesthesia. In this study we sedated the mechanically ventilated patients in general ICU (Intensive Care Unit ICU) with propofol and midazolam as sole agent or in combination with the two sedatives. Our aims were to investigate the predicted drug effective site concentration of different sedatives with which to reach the different levels of sedation and observe the correlation between BIS and RASS (The Richmond Agitation-Sedation Scale, RASS ). It is one of our aims to find a economic and proper method which can be used in administering sedatives in ICU, too.Method Sixty critically ill patients undergoing mechanical ventilation in ICU were randomly divided into three groups: propofol group (group A) , midazolam group (group B) and propofol-midazolam group (group C). we observed the predicted drug effective site concentration, BIS and life sign of the patients involved in these three groups at different RASS. The recovery time, total dosage in 8 hours and the incidence of undesired reaction of the three administration method were compared too.Results In group A, the effective site concentration of propofol to keep the patient at ideal sedation level(RASS=-2~-3) was 1.26±0.19~1.52±0.18ug/ml and it was 0.50±0.95ug/ml~ 1.01 ±0.24ug/ml in group C. In group B, the effective site concentration of midazolam was 97.05 ± 14.51 ~ 134.75±9.66ng/ml to make the patients at this sedation level. The corresponsive BIS was 66.10±2.52~71.05± 1.45 when patients was at ideal sedation level.Among the three groups, the recovery time is similar between the group A and group C, but it was longer in group B than the other groups(P<0.05). the rate of sleeping again is higher in group B either(P<0.05). There is no significantly difference on the rate of the hypotension and nausea among this three groups(P>0.05). In the group C, the total dosage of the two sedatives to maintain the proper sedation level within 8 hours was reduced dramatically in contrast to the other two groups(P<0.05).Positive correlation was proved between RASS and BIS, the coefficient of correlation was 0.94,0.92,0.90 in different group (P<0.01) and 0.93 to all of the patients(N=60,P<0.01).Conclusion 1 It will offer some reference for TCI and BIS be used in ICU that the effective site concentration of propofol or midazolam we gained from this study. 2 In these three administration method, the using solely of propofol was the most controllable but expensive, when midazolam was used solely the recovery time was very long, thus unhandy. Contrary, TCI the two drugs synchronously can reduce the total dosage significantly, avoid the shortcoming when neither of the two sedatives was administrated solely, retained the respective merit of the two drugs at the same time. Therefore it is a perfect way administrating sedatives in ICU. 3 BIS was highly correlated with RASS, can be used to guide sedation and promote the security of sedation therapy.