Effects of dexmedetomidine on cellular immune function during analgesia with morphine after radical resection for esophageal cancer

Abstract

Objective To evaluate the effects of dexmedetomidine on the cellular immune function during analgesia with morphine after radical resection for esophageal cancer in the patients.Methods Sixty patients of both sexes,of ASA physical status Ⅰ or Ⅱ,after radical resection for esophageal cancer under general anesthesia,were randomly divided into 2 groups (n =30 each) using a random number table:control group (group C) and dexmedetomidine group (group Dex).Patient-controlled intravenous analgesia (PCIA) was performed immediately after operation in the two groups.In group C,the PCIA solution (150 ml) contained morphine 0.48 mg/kg.In group Dex,the PCIA solution (150 ml) contained morphine 0.48 mg/kg and dexmedetomidine 1 μg/kg.The postoperative visual analogue scale (VAS) scores were maintained ≤ 3.The consumption of morphine was recorded within 24,48 and 72 h after operation.The adverse effects such as nausea,vomiting,pruritus,bradycardia,hypotension,oversedation and respiratory depression were also recorded after operation.Before induction of anesthesia (T0),immediately after extubation (T1),and at 24,48 and 72 h after operation (T2-4),venous blood samples were obtained for determination of the levels of T-lymphocyte subsets (CD3+,CD4+,CD8+) and natural killer (NK) cells by flow cytometry.CD4+/CD8+ ratio was calculated.Results Compared with group C,the consumption of morphine within 24,48 and 72 h after operation and incidence of nausea,vomiting and pruritus after operation were significantly decreased in group Dex.The levels of CD3+,CD4+,CD4+/CD8+ ratio and NK cells were significantly lower at T1-4 than at T0 in the two groups.The levels of CD3+,CD4+,CD4+/CD8+ ratio and NK cells were significantly higher at T1-4 in group Dex than in group C.Conclusion Dexmedetomidine can improve the cellular immune function during analgesia with morphine after radical resection for esophageal cancer in the patients. Key words: Dexmedetomidine ; Morphine ; Analgesia, patient-controlled ; Immunity, cellular