Effects of dexmedetomidine on perioperative cellular immune function and micro-metastasis in blood circulation in patients undergoing radical operation for colon cancer / 中华麻醉学杂志

ABSTRACT

Objective To investigate the effects of dexmedetomidine on perioperative cellular immune function and micro-metastasis in blood circulation in patients undergoing radical operation for colon cancer.Methods Sixty ASA Ⅰ or Ⅱ patients,aged 38-69 yr,weighing 45-67 kg,undergoing radical operation for colon cancer,were randomly divided into 2 groups (n =30 each) ∶ dexmedetomidine group (D group) and control group (C group).Anesthesia was induced with midazolam,cisatracurium and sufentanil,and maintained with propofol,remifentanil and sevoflurane.After tracheal intubation,a loading dose of dexmedetomidine 1 μg/kg was injected intravenously,followed by infusion at 0.5μg· kg-1 · h-1 until the end of operation in D group.The equal volume of normal saline was administered in C group.Venous blood samples were obtained at 5 min before induction of anesthesia (T0),1 h after beginning of operation (T1),the end of operation (T2) and 24 h after the end of operation (T3) for determination of the levels of T lymphocyte subsets (CD3+,CD4+,CD8+) and NK cells by flow cytometry.CD4+/CD8+ ratio was calculated.Cytokeratin 20 (CK20) expression in circulation was detected by RT-PCR at T0 and T3 and the positive rate was calculated.Results Compared with the baseline value at T0,the levels of CD3+ and CD4+,CD4+/CD8+ ratio and level of NK cells were significantly decreased at T2 and T3 in group C,and the levels of CD3+ and CD4+ were significantly decreased at T2 and T3 in group D (P ＜ 0.05).The levels of CD3+,CD4+ and NK cells at T2 and T3 were significantly higher and positive rate at T3 was significantly lower in group D than in group C (P ＜ 0.05).Conclusion Dexmedetomidine can improve the cellular immune function and decrease the probability of micro-metastasis in blood circulation in patients undergoing radical operation for colon cancer.