Use of bispectral index and narcotrend monitor in inspecting the depth of anesthesia in elderly patients induced different doses of propofoi infusion

Objective To observe the changes of HR,MAP,BIS and Narcotrend induced by different doses of propofol in elderly patients. Methods One hundred elder patients(60 ～ 85 years old), AS A class Ⅰ or Ⅱ, scheduled for selective surgeries,were divided equally into 5 different doses of propofol( constant intravenous injection for 1min) groups of 0.5mg/kg( Ⅰ ) ,0. 75mg/kg( Ⅱ ) ,1.0mg/kg(Ⅲ) ,1.25mg/kg( Ⅳ)and 1.5mg/kg(Ⅴ). HR,MAP,BIS and Narcotrend were monitored before propofol injection and at 1 and 5 min after propofol injection. Results HR of 5 group s as similar. At 1 min after pmpofol injection, MAP decreased remarkably compared with at before in all 5 groups( t =2. 17,2.84,2.49,5.63,7.10, all p ＜ 0.05 ), which in group Ⅳ and Ⅴ decreased significantly compared with at in group Ⅰ, Ⅱ and Ⅲ(t =4.67,2.77,2.45,5.49,4.57,2. 18,all P＜0.05).At 1 min after propofol injection,BIS and NI values decreased compared with at before in all 5 groups(t =7.74,11.74,28.18,30.34,45.28, 6. 65,10.52,17.27,26.28,30. 14,allP ＜0.05) ,which in groupⅢ, Ⅳ and Ⅴ were significantly lower than those in group Ⅰ and Ⅱ (t =12.59,11.08,16.72,15.12,17.67,15.64,allP＜0.05).Dose of propofol was negatively correlated with BIS and NI value ( r =-0. 898/0. 930, P ＜ 0.01 ). Conclusion Propofol 1.0mg/kg constant injection should meet the sedation and hypnosis demand of general anesthesia in elderly patients and could not inhibit circulatory system; Bispectral Index and Narcotrend could accuratly monitor depth of anesthesia in elderly patients. Key words: Anesthesia;  Bispectral index;  Narcotrend;  Propofol;  Aged