Abstract The aim of this study was to evaluate the predictive value of preoperative spirometric and arterial gas data on severe pulmonary complications (PC) after elective abdominal surgery. We retrospectively studied 480 patients, 254 males and 226 females, mean ( SD ) age 63 (11) years, at risk for PC according to standardized criteria, who underwent laparotomy for resection of gallbladder for gallstones (44% of patients), resection of colon, rectum or stomach for malignant tumours (37%), and other abdominal surgery (19%). The overall incidence of postoperative PC was 18%. In a logistic regression analysis adjusted for smoking habit and clinical history of chronic bronchitis, FEV 1<61% of predicted [odds ratio (OR)=16·86, 95% confidence interval (95%CI)=5·62−50·58] and PaO 2<9·33 kPa (OR=6·42, 95%CI=2·48−16·61) were the main determinants of PC. Ischaemic heart disease (OR=3·44, 95%CI=1·08−10·93), operation for malignant tumours (OR=3·24, 95%CI=1·75−6·00) and age (OR=1·04, 95%CI=1·00−1·08) were also independent predictors of PC. Patients with moderate-to-severe airway obstruction combined with hypoxaemia had a significant higher risk of PC in comparison with patients with a normal respiratory pattern. Taking into account age, type of operation, and comorbidity, a preoperative respiratory functional assessment could be useful in identifying an increased risk of major PC in selected patients.