Effects of different depths of sedation on postoperative cognitive function in elderly patients with mild cognitive impairment / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the effects of different depths of sedation on postoperative cognitive function in elderly patients with mild cognitive impairment.Methods A total of 100 patients with mild cognitive impairment before surgery,aged 65-75 yr,weighing 55-75 kg,of American Society of Anesthesiologists physical status Ⅱ or Ⅲ,scheduled for elective gynecological surgery under general anesthesia,were divided into Ⅰ and Ⅱ groups (n =50 each) using a random number table method.Propofol was given by closed-loop target-controlled infusion,and the target plasma concentration was automatically regulated.The bispectral index value was maintained at 40-50 in group Ⅰ and at＞50-60 in group Ⅱ.Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) were used to evaluate the cognitive function at 1 day before operation (T0) and 7 days after operation (T1),and the development of postoperative cognitive dysfunction (POCD) was recorded.Venous blood samples were collected at T0 and T1 for determination of the concentrations of serum interleukin-10 (IL-10) and tumor necrosis factor-alpha (TNF-α) by enzyme-linked immunosorbent assay.Results Compared with the baseline value at T0,MoCA and MMSE scores were significantly decreased at T1,and the serum concentrations of IL-10 and TNF-α were increased in both groups (P＜0.05).Compared with group Ⅰ,MoCA and MMSE scores were significantly decreased at T1,and the incidence of POCD was increased,the serum concentration of TNF-α was increased,and the serum concentration of IL-t0 was decreased in group Ⅱ (P ＜ 0.05).Conclusion Maintaining BIS value at 40-50 during operation can decrease the development of POCD in elderly patients with mild cognitive impairment,which may be related to reduced systemic inflammatory responses.