关键词: 结直肠肿瘤；认知障碍；老年人；手术后并发症；髓样细胞触发受体；白介素6；肿瘤坏死因子&alpha, ；乌司他丁；右美托咪定

Abstract: Background　Perioperative neurocognitive disorders （PND） are a kind of mental disorders syndrome characterized by an acute onset and fluctuating course and induced by perioperative anesthesia and surgery with no effective preventive measures available.Thus，how to prevent and treat PND has become a hot topic in recent years.Objective　To investigate the effect of dexmedetomidine with ulinastatin on PND in elderly patients undergoing laparoscopic surgery for colorectal cancer.Methods　Six hundred and fifty-four elderly patients who were scheduled for elective laparoscopic surgery for colorectal cancer under general anesthesia were recruited from Nantong University Haian Hospital，Affiliated Hospital of Nantong University，and Nantong First People’s Hospital from May 2018 to June 2019，18 of them were excluded（7 were due to suspended surgery，and 11 disagreed to attend this study），and other 636 were finally included and equally randomized into control group （received 0.9% sodium chloride solution by infusion pump），dexmedetomidine group（received a loading dose of dexmedetomidine hydrochloride of 0.5 μg/kg using a micro-pump within 15 minutes before anesthesia induction，followed by continuous infusion at 0.3 μg?kg-1?h-1 until the end of surgery），ulinastatin group （received a loading dose of ulinastatin of 2 ku/kg using a micro-pump within 15 minutes before anesthesia induction，followed by continuous infusion at 1 ku·kg-1·h-1 until the end of surgery） and dexmedetomidine with ulinastatin group（received the same dexmedetomidine regimen as dexmedetomidine group and the same ulinastatin regimen as ulinastatin group）.ELISA was used to detect plasma levels of sTREM1，IL-6 and TNF-α on the day before surgery and on the 1st，3rd，and 7th days after surgery，respectively.Confusion Assessment Method （CAM） was used to assess delirium on the 1st，3rd，and 7th days after surgery，respectively.Z-score was used to assess neurocognitive disorder at 30，60 and 90 days after surgery，respectively.Results　Compared with the control group，the average levels of plasma sTREM1，IL-6 and TNF-α were significantly decreased in other three groups at each measurement （P<0.05）.Compared with dexmedetomidine and ulinastatin groups，the average levels of plasma sTREM1，IL-6 and TNF-α were significantly decreased in dexmedetomidine with ulinastatin group at each measurement（P<0.05）.Compared with the control group，postoperative delirium prevalence was significantly decreased in other three groups at each assessment（P<0.008 3）.Compared with dexmedetomidine and ulinastatin groups，the postoperative delirium prevalence at 7 days after surgery was significantly decreased in dexmedetomidine with ulinastatin group （P<0.008 3）.Compared with the control group，the postoperative neurocognitive disorders prevalence was significantly decreased in dexmedetomidine with ulinastatin group at each measurement（P<0.008 3）.Compared with dexmedetomidine and ulinastatin groups，the neurocognitive disorders prevalence at 60 days after surgery was significantly decreased in dexmedetomidine with ulinastatin group （P<0.008 3）.Conclusion　In elderly patients undergoing laparoscopic surgery for colorectal cancer，ulinastatin with dexmedetomidine may decrease the incidence of short-term postoperative delirium and long-term postoperative neurocognitive disorders，which may be achieved by down-regulating the levels of plasma sTREM1，IL-6 and TNF-α proteins.

Key words: Colorectal neoplasms；Congnition disorders；Aged；Postoperative complications；Triggering receptor expressed on myeloid cell；Interleukin-6；Tumor necrosis factor-&alpha, ；Ulinastatin；Dexmedetomidine