The Effects Of Edaravone On Postoperative Cognitive Function In Elderly Patients Undergoing Knee Replacement Surgery

Objective To investigate the influrence of edaravone on postoperative cognitive function in elderly patients undergoing knee replacement surgery.Methods Ninety ASA Ⅰ～Ⅱ elderly patients,underwent knee arthroplasty surgery,aged 65-79 years old,MMSE score> 23,were randomly divided in edaravone group (group E) and control group (group C). The group E was given edaravone 0.5 mg/kg while the same amount of sodium chloride injection in group C 30 min before anesthesia indunction. The cognitive function of the patients was assessed preoperative, on the 1st and 5th postoperative day with the approximate same scales with ISPOCD studies. These scales included:(1) mini-mental state examination, MMSE (2) Digit Span Test (3) trail-making test,TMT (4) Hopkins Verbal Learning Test-Revised, HVLT-R (5) Digit Symbol Coding (6) Verbal Fluency Test,VF, animal naming. Test the level of serum ALT/AST/BUN/Cre on preoperative、the 1st..3rd and 5th postoperative day.Results On the 1st postoperative day,the incidence of postoperative cognitive dysfunction were 11.11%,33.33% in group E and group C; On the 5th postoperative day, the corresponding data was 6.67% and 22.22%,respectively.On the 1st and 5th postoperative day, the incidence of POCD in group E was lower than that of group C(P=0.01,P=0.04).Two group of patients with MMSE score compared with preoperative basic value difference had no statistical significance on the 1st and 5th postoperative day (P> 0.05). The score of TMT were increased compared with preoperative basic value on both of two group on the 1st postoperative day (P=0.03,P=0.01). The score of HVLT-R on group E was higher than group C on the 5th postoperative day (P=0.01).The difference of two group of patients in the serum ALT/AST/BUN/Cre concentration compared with preoperative basic value were not statistically significant on the 1st,3rd and 5th postoperative day (P> 0.05). There was no difference between group E and group C with the serum concentration of ALT/AST/BUN/Cre on preoperative, the 1st,3rd and 5th postoperative day.Conclusion The edaravone according to the dose of 0.5mg/kg dissolved in 100 ml of sodium chloride injection, static drip off within 30 minutes is not bad for elderly patients with liver and kidney function.The data indicate that edaravone according to the dose of 0.5mg/kg can reduce the occurance of POCD in elderly patients undergoing knee arthroplasty, improve the postoperative cognitive function of senile patients.