The Effect Of Dexamethasone On POCD In Elderly Patients

Objective: To observe the effect of dexamethasone on postoperative cognitive function of elderly patients undergoing radical resection of colorectal cancer,and explore the possible mechanism of mast cell degranulation,furthermore,reduce the incidence and provides new unique therapeutic targetsthe for postoperative cognitive impairment in elderly patients.Methods: Sixty colorectal carcinoma patients under general anesthesology,ASA I-III grade,aging 60-80 years old,were randomly divided into two groups: test group(dexamethasone group Group D,n=30)and control group(saline group,group C,n=30).One hour before operation,the experimental group was given a intravenous injection of dexamethasone for 10 mg(2 ml).The control group was given an equal volume of normal saline.The anesthsia introduction of all of the two group patients are introvenous anesthesia intrudution,then tracheal intubation was performed.The maintenance of anesthesia is Intravenous-inhalation anesthesia.The PCIA was used to pstoperative analgesia.Every patients were detected serum complement C3,C5,5-HT,TNF-? and S100? protein concentration with ELISA 1 day before surgery(T0),1 day after surgery(T1),3 days after surgery(T2),besides,MoCA tested in 1 day before the surgery(T0),1 day after the surgerry(T1),3 days after surgery(T2),7 day after the surgery(T3),MMSE tested in 1 day after surgery(T1),Cog-12 tested in 3 days after surgery(T2),and CASI tested in 7 day after the surgery(T3),were recorded from the two groups of patients.Results: 1.General information: There was no statistically significant difference in the sex ratio,age,BMI,operation time,anesthesia time,extubation time,hospital stay and ASA grade between the two groups(P>0.05).2.Serum complement C3: There was no significant difference in the concentration of serum complement C3 between the two groups in T0(P>0.05);The concentration of serum complement C3 in the time point(T1?T2)was significantly lower compared with it in T0 between the two group(P<0.05).The concentration of serum complement C3 of group D was lower than that of group C in the time point(T1?T2)(P<0.05).3.Serum complement C5: There was no significant difference in concentration of serum complement C5 between this two group in T0(P>0.05);Serum complement C5 concentration in the time point(T1?T2)was significantly higher than it in T0 between the two group(P<0.05);The concentration of serum complement C5 of group D was significantly lower than that of group C in the time point(T1)(P<0.05).4.Serum TNF-?: There was no significant difference in serum TNF-? levels between the two groups in T0(P>0.05);in the time point(T1?T2),The postoperative concentration of serum TNF-? in was significantly higher than that T0 between the two group(P<0.05).In the time point(T1?T2),The concentration of serum TNF-? of group D was lower than that of the group C(P<0.05).5.Serum 5-HT: There was no statistically significant difference in serum 5-HT levels between the two groups in T0(P>0.05);in the time point of T1 and T2,postoperative Serum 5-HT levels were significantly higher than it in T0(P<0.05);The concentration of Serum 5-HT of group D In the time point(T1?T2)was lower than that of the group C(P<0.05).6.Serum S100? protein: There was no significant difference in the concentration of serum S100? protein in T0 between the two groups(P>0.05);in the time point of T1 and T2,the concentration of serum S100? protein were significantly higher than it in T0(P<0.05);The concentration of serum S100? protein of group D in T1 and T2 was significantly lower than that of the group C(P<0.05).7.MoCA scores: There was no significant difference in MoCA scores between the two groups in T0(P>0.05);The MoCA score in the time point(T1,T2,T3)was significantly lower than it in T0 in the two group(P<0.05).The MoCA score of group D in the time point(T1,T2,T3)MoCA score was higher than that of C group(P<0.05).8.MMSE,Cog-12,CASI scores: The MMSE score of group D in T1 was higher than that in group C(P<0.05);Cog score of group D in T2 was lower than that in group C(P<0.05).There was no significant difference in CASI of group D score in T3 compared with group C(P>0.05).Conclusion: Intravenous injection of 10 mg dexamethasone 1 hour before surgery can improve the postoperative cognitive function of elderly patients undergoing elective colorectal cancer radical resection and reduce brain injury.The mechanism may be through the reduction of serum complement C3,C5,and the inhibition of mast cell degranulation.