Objective To evaluate the lung protection of flurbiprofen axetil combined with protective mechanical ventilation in the patients undergoing thoracic surgery. Methods Sixty patients of both sexes, aged 25-64 yr, with body mass index of 18-29 kg/m2, of American Society of Anesthesiologists physical status Ⅰ or Ⅱ, scheduled for elective radical resection of esophageal cancer under general anesthesia, were randomly divided into 4 groups(n=15 each)using a random number table: conventional mechanical ventilation(group CMV), flurbiprofen axetil combined with conventional mechanical ventilation group(group F+ CMV), protective mechanical ventilation group(group PMV), and flurbiprofen axetil combined with protective mechanical ventilation group(group F+ PMV). Volume-controlled ventilation was performed in the 4 groups.Conventional mechanical ventilation mode was as follows: tidal volume(VT)10 ml/kg and respiratory rate(RR)10-12 breaths/min during two-lung ventilation(TLV); VT 8 ml/kg and RR 15-18 breaths/min during one-lung ventilation(OLV). Protective mechanical ventilation mode was as follows: VT 6 ml/kg, positive end-expiratory pressure 5 cmH2O, RR 15-18 breaths/min(during OLV)or 10-12 breaths/min(during TLV), inspiratory/expiratory ratio 1∶2, fraction of inspired oxygen 100%, oxygen flow rate 1-2 L/min.The end-tidal pressure of carbon dioxide was maintained at 35-45 mmHg in the 4 groups.Flurbiprofen axetil 2 mg/kg was injected intravenously at 15 min before skin incision, and the patient-controlled intravenous analgesia(PCIA)was used after surgery.PCIA solution contained sufentanil 100 μg and flurbiprofen axetil 2 mg/kg in 100 ml of normal saline.The PCIA pump was set up with a 0.5 ml bolus dose, a 15 min lockout interval and background infusion at a rate of 2 ml/h, and visual analogue scale score was maintained ≤3.Before induction of anesthesia(T0), at 15 min of TLV(T1), at 1 and 2 h of OLV(T2), at 2 h after OLV(T3), at the end of surgery(T4), and at 24 h after surgery(T5), blood samples were taken from the radial artery for determination of arterial oxygen partial pressure, and oxygenation index was calculated.The occurrence of abnormal pulmonary function was recorded during and after surgery.The parameters of pneumodynamics were recorded at T1-4.Central venous blood samples were taken at T0, 4, 5 to measure the concentrations of tumor necrosis factor-alpha, interleukin-6(IL-6), and IL-8 in serum. Results Compared with group CMV, arterial oxygen partial pressure, oxygenation index, and dynamic lung compliance were significantly increased, the peak airway pressure, airway plateau pressure and concentrations of tumor necrosis factor-alpha, IL-6, and IL-8 in serum were significantly decreased, and the incidence of abnormal pulmonary function after surgery was significantly decreased in the other 3 groups, especially in group F+ PMV(P<0.05). Conclusion Flurbiprofen axetil used before and after surgery has lung protection, and it produces better efficacy when combined with protective mechanical ventilation in the patients undergoing thoracic surgery. Key words: Cyclooxygenase inhibitors; Respiration, artificial; Respiratory distress syndrome, adult; Thoracotomy