Effects of dexmedetomidine on activity of nuclear factor kappa B in neutrophil granulocytes during one-lung ventilation in patients undergoing pulmonary lobectomy

Objective To evaluate the effects of dexmedetomidine on the activity of nuclear factor kappa B (NF-κB) in neutrophil granulocytes during one-lung ventilation in the patients undergoing pulmonary lobectomy.Methods Thirty-eight ASA physical status Ⅰ or Ⅱ patients,aged 40-64 yr,weighing 50-75 kg,scheduled for elective pulmonary lobectomy,were randomized into 2 groups (n =19 each) using a random number table:control group (group C) and dexmedetomidine group (group D).In group D,dexmedetomidine 1.0 μg/kg was infused intravenously over 15 min before induction of anesthesia,followed by infusion at a rate of 0.5 μg· kg-1 · h-1 until 30 min before the end of operation.The equal volume of normal saline was given in group C.At 5 min after intubation,0,30 and 60 min of one-lung ventilation,0 and 30 min of two-lung ventilation,and 30 min after operation,blood samples were taken from the radial artery for blood gas analysis and for measurement of plasma concentrations of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6).The oxygenation index and respiratory index were calculated.The nuclear protein of neutrophil granulocytes was extracted for measurement of NF-κB DNA-binding activity.Results Compared with group C,the respiratory index,plasma concentrations of TNF-α and IL-6 and NF-κB DNA-binding activity were significantly decreased,and no significant difference was found in the oxygenation index in group D.Conclusion Dexmedetomidine can inhibit the activation of NF-κB in neutrophil granulocytes and is helpful in reducing the systemic inflammatory responses during one-lung ventilation in the patients undergoing pulmonary lobectomy. Key words: Dexmedetomidine ;  NF-kappa B ;  Neutrophils ;  Respiration, artificial