AIM: To investigate the incidence of various types of postoperative pulmonary complications (POPCs) and to evaluate the significance of perioperative arterial blood gases in patients with esophageal cancer accompanied with chronic obstructive pulmonary disease (COPD) after esophagectomy. METHODS: Three hundred and fifty-eight patients were divided into POPC group and COPD group. We performed a retrospective review of the 358 consecutive patients after esophagectomy for esophageal cancer with or without COPD to assess the possible influence of COPD on postoperative pulmonary complications. We classified COPD into four grades according to percent-predicted forced expiratory volume in 1 s (FEV1) and analyzed the incidence rate of complications among the four grades. Perioperative arterial blood gases were tested in patients with or without pulmonary complications in COPD group and compared with POPC group. RESULTS: Patients with COPD (29/86, 33.7%). had more pulmonary complications than those without COPD (36/272, 13.2%) (P < 0.001). Pneumonia (15/29, 51.7%), atelectasis (13/29, 44.8%), prolonged O-2 supplement (10/29, 34.5%), and prolonged mechanical ventilation (8/29, 27.6%) were the major complications in COPD group. Moreover, patients with severe COPD (grade II B, FEV1 < 50% of predicted) had more POPCs than those with moderate(grade II A,50%-80% of predicted) and mild (grade I >= 80% of predicted) COPD (P < 0.05). PaO2 was decreased and PaCO2 was increased in patients with pulmonary complications in COPD group in the first postoperative week. CONCLUSION: The criteria of COPD are the critical predictor for pulmonary complications in esophageal cancer patients undergoing esophagectomy. Severity of COPD affects the incidence rate of the pulmonary complication, and percent-predicted FEV1 is a good predictive variable for pulmonary complication in patients with COPD. Arterial blood gases are helpful in directing perioperative management. (C) 2006 The WJG Press. All rights reserved.