Abstract
Lung expansion techniques (LET) are widely used to prevent postoperative pulmonary complications (PPC). However, the effect of each of these techniques on thoracoabdominal mechanics and its relationship with the incidence of PPC after abdominal surgery remain unclear. HYPOTHESIS: The LET that promotes higher chest wall volume with lower respiratory effort would be better to prevent PPC. OBJECTIVE: To compare the effect of LET on pulmonary volumes, respiratory muscle activation and incidence of PPC after abdominal surgery. METHODS: This randomised and controlled trial enrolled 137 patients randomly assigned into 4 groups: control (n=35), volume incentive spirometry (n=34); flow incentive spirometry (n=33) and deep breathing (n=35). Intervention groups performed 50 repetitions of specific technique, 3 times a day during 5 days. PPC (pneumonia or atelectasis or severe hypoxemia) were analysed by a blinded evaluator until hospital discharge. Chest wall volume (via optoelectronic plethysmography) and sternocleidomastoid and superior and inferior intercostal muscles activation (via electromyography) were assessed before and 3 days after surgery, during baseline and deep breathings. ANOVA and chi-square were tested considering intention to treat. RESULTS: Groups were homogenous for age, gender, BMI and lung function. After surgery, all groups were similar on chest wall volume variation and respiratory muscle activation. The incidence of PPC was higher on deep breathing group (p<0.05). CONCLUSION: LET have similar effect on thoracoabdominal mechanics and do not prevent PPC in patients undergoing upper abdominal surgery.
- © 2014 ERS
