Objective: Pulmonary complications that occur postoperatively are important reasons of mortality and morbidity. The aim of this study is to research the relation between pulmonary complications, and preoperative risk factors, pulmonary risk index (PRI) and anesthesia type performed in patients who have undergone orthopedic surgery. Method: After Ethical Community consent, 1406 elective cases which were operated by Department of Orthopedics and Traumatology of Uludaǧ University Medical Faculty between January 2007- June 2008. Gender, age, clinical ASA status and anaesthesia types of all the subjects were recorded. Additional systemic diseases and operation types were also recorded. PRI of all patients were calculated. Six parameters were evaluated in this index. Postoperative pulmonary complications (PPC) determined in 24 hours postoperatively and mortality were also recorded. Atelectasis, pneumonia and respiratory failure were recorded as PPC. Results: Postoperative pulmonary complications developed in 44 (3.1%) subjects and 1 subject died in the early postoperative period. The rate of developing PPC was found out to be higher in patients older than mean age, with high ASA status, with additional diseases, with a high body mass index (BMI), with patology in preoperative clinical evaluation, with abnormal results in pulmonary function tests (PFTs) and the ones who had PaCO2 > 45mmHg in arterial blood samples. There was no relation between smoking in the last 8 weeks and PPK. Postoperative pulmonary complications rate was higher in patients who were administered general anesthesia compared with patients who had regional anaesthesia. Pulmonary risk index was higher in the subjects who developed PPC. Conclusion: Eventually, in the preoperative period, patients must be evaluated by taking a good medical history, performing an appropriate physical examination and it if deemed neccessary, additional examinations like PFTs must be used. Pulmonary rise factors must be evaluated, and for critical patients, regional anaesthesia techniques should be retained.