The Study Of Dexmedetomidine Of The Neuroprotective Effect In Patients Undergoing Craniotomy

Objective: To observe the effect of dexmedetomidine (DEX) onserum S100β, neuron specific enolase (NSE),interleukin-6(IL-6), tumornecrosis factor-alpha (TNF-α) levels, Glasgow Coma Scale (GCS) andMini Mental State Examination (MMSE) scores24hours before surgeryand24hours after surgery, and change of Glasgow Outcome Scale (GOS)scores1month after sugery in patients undergoing craniotomy，and toexplore neuroprotective effect of DEX and its possiblemechanism．Mthods: Forty five patients(with intracranial aneurysm，gliomas or meningiomas）undergoing craniotomy were randomly dividedinto3groups: blank control group (group C), group DEXⅠ,group DEXⅡ,15in each group. Intravenous cannula established after patientsentered operating room, BP，HR，RR，SpO2，ECG， PETCO2and BISwere monitored. Patients in group DEXⅠwere injected loading dose0.5μg/kg(10min)of DEX before skin incision, and continous intravenousinjected at the rate of0.5μg/(kg.h) to the end of operation. Patients ingroup DEXⅡwere injected loading dose1μg/kg(10min) before skinincision, and continous intravenous injected at the rate of1μg/(kg.h) to the end of surgery. GCS, MMSE scores were determined24hours beforeand after operation in all patients，GOS scores were assessed1monthafter operation，and calculated the ΔMMSE (the difference of MMSEbetween preoperative and postoperative). Serum S100β, NSE, IL-6,TNF-α levels were determined24hours before operation，after cerebraldura mater incision，and24hours after operation. Results:1. MMSE，GCS and GOS scores：MMSE scores preoperative were no significancebetween groups(p>0.05). MMSE scores24hrs postoperative were nosignificance between Group DEX I and group DEX II (p>0.05), but weresignificantly higher than group C (p<0.05). ΔMMSE were no significancebetween Group DEX I and group DEX II (p>0.05), but were significantlylowerer than group C (p<0.05). There were no significant difference inGCS and GOS scores among three groups. In group C, MMSE scorespreoperative was lower than postoperative (p<0.05). However, there wasno significant difference within Group DEX I and group DEX II(p>0.05).ΔGCS were no significance difference among three groups（p>0.05).2.Serum S100β, NSE: They were normal at T0in three groups, withoutsignificance (p>0.05). There were no significant difference in S100β,NSE at T1between DEXⅠand group C, and between DEXⅠandDEXⅡ(p>0.05); but S100β and NSE in DEXⅡ was significantly lowerthan that in group C (p<0.05).Within groups, S100β, NSE increasedgradually, and then decreased, highest at T2, second at T3, there were significant difference between all time points(p<0.05), except nosignificance between T0, T1in S100β and NSE of group DEXⅡ.3. SerumIL-6,TNF-α:They were normal at T0in the three groups,withoutsignificance (p>0.05). There were no significant difference in IL-6,TNF-α at T1between DEXⅠand group C, and between DEXⅠandDEXⅡ(p>0.05), but IL-6, TNF-α in DEXⅡwas significantly lower thanthat in group C (p<0.05).There were significantly difference in IL-6,TNF-α at T2,T3between DEXⅠand DEXⅡ(p<0.05), but bothsignificantly lower than group C (p<0.05). In all groups, IL-6, TNF-αincreased gradually, and then decreased, highest at T2, second at T3, therewere significant difference between all points(p<0.05), except nosignificance between T1, T3in IL-6of group DEXⅡ(p>0.05).Conclusions: Dexmedetomidine could protect brain function in patintsundergoing craniotomy, its possible mechanism was to decrease serumIL-6and TNF-α levels during operation and24hrs after operation.