The purpose of this study was to determine the incidence of different postoperative pulmonary complications (PPCs) and their associated risk factors in patients with severe chronic obstructive pulmonary disease (COPD) (forced expiratory volume in 1 s [FEV1] < or = 1.2 L and FEV1/forced vital capacity (FVC) < 75%) undergoing noncardiothoracic operations. Thirty-nine of 105 patients (37%) had one or more PPCs (death, pneumonia, prolonged intubation, refractory bronchospasm, or prolonged intensive care unit (ICU) stay). Thirty-eight of 39 patients (97%) with a PPC had an anesthetic duration > 2 h. Our study patients had a 47% 2-yr mortality rate. We determined specific risk factors for each PPC by analyzing potential preoperative and intraoperative risk factors. Pulmonary factors alone do not predict the likelihood of PPCs in severe COPD patients. Multiple logistic regression identified composite scoring systems, such as the ASA physical status, as the best preoperative predictors of PPCs, probably because they include both pulmonary and nonpulmonary factors. During the intraoperative period, avoiding general anesthesia with tracheal intubation may decrease the risk of postoperative bronchospasm. Shortening the duration of surgery and anesthesia may decrease the risk of prolonged ICU stay.