Background Following thoracotomy, patients frequently receive routine respiratory physiotherapy which may include incentive spirometry, a breathing technique characterised by deep breathing performed through a device offering visual feedback. This type of physiotherapy is recommended and considered important in the care of thoracic surgery patients, but high quality evidence for specific interventions such as incentive spirometry remains lacking.

Methods 180 patients undergoing thoracotomy and lung resection participated in a prospective single-blind randomised controlled trial. All patients received postoperative breathing exercises, airway clearance and early mobilisation; the control group performed thoracic expansion exercises and the intervention group performed incentive spirometry.

Results No difference was observed between the intervention and control groups in the mean drop in forced expiratory volume in 1 s on postoperative day 4 (40% vs 41%, 95% CI −5.3% to 4.2%, p=0.817), the frequency of postoperative pulmonary complications (PPC) (12.5% vs 15%, 95% CI −7.9% to 12.9%, p=0.803) or in any other secondary outcome measure. A high-risk subgroup (defined by ≥2 independent risk factors; age ≥75 years, American Society of Anaesthesiologists score ≥3, chronic obstructive pulmonary disease (COPD), smoking status, body mass index ≥30) also demonstrated no difference in outcomes, although a larger difference in the frequency of PPC was observed (14% vs 23%) with 95% CIs indicating possible benefit of intervention (−7.4% to 2.6%).

Conclusions Incentive spirometry did not improve overall recovery of lung function, frequency of PPC or length of stay. For patients at higher risk for the development of PPC, in particular those with COPD or current/recent ex-smokers, there were larger observed actual differences in the frequency of PPC in favour of the intervention, indicating that investigations regarding the physiotherapy management of these patients need to be developed further.