[Lung expansion exercises: improve lung function capacity in the postoperative period following cardiac surgery]

The objective was to analyze the effect of pulmonary expansion exercises on pulmonary functional capacity in patients undergoing cardiac surgery. An integrative review with a quantitative approach was conducted, structured based on methodological principles of PRISMA 2020. The research question was formulated using the PIO framework. The literature search was performed in PubMed, BVS, Journal of PeriAnesthesia Nursing, Epistemonikos, SciELO, ScienceDirect, and EBSCO, using DeCS and MeSH terms combined with Boolean operators. A total of 45 potentially relevant studies were identified, of which 12 met the inclusion criteria, incorporating both primary studies and systematic reviews. Methodological quality was assessed using the FLC instrument version 3.0 and the Oxford Centre for Evidence-Based Medicine classification. Risk of bias was evaluated according to study design, using RoB 2 for randomized controlled trials and ROBIS for systematic reviews. The synthesis considered comparisons across levels of evidence to minimize potential duplication of results. Findings suggest that inspiratory muscle training is associated with improvements in respiratory muscle strength, pulmonary function, and functional capacity. Additionally, the use of volume-oriented incentive spirometry, particularly when guided by nursing staff, is associated with favorable pulmonary outcomes in the postoperative period.