Effectiveness of Active Cycle of Breathing Technique in Improving Physiological and Functional Outcomes Following Coronary Artery Bypass Graft Surgery: A Narrative Review.

Coronary artery bypass grafting (CABG) is a common surgical approach for advanced coronary artery disease unresponsive to conservative or percutaneous treatments. Despite its benefits in symptom relief and long-term outcomes, CABG is associated with notable postoperative respiratory complications. As such, respiratory physiotherapy plays a crucial role in recovery. The active cycle of breathing technique (ACBT) is a non-invasive, evidence-based method that promotes lung ventilation, secretion clearance, and respiratory function. This review aimed to describe the effectiveness of the ACBT in enhancing physiological and functional outcomes following CABG surgery. A review of PubMed and Google Scholar studies was conducted, with relevant articles analyzed for study design, patient profiles, intervention protocols, and clinical outcomes. Fifteen articles were included, encompassing studies on pulmonary complications following CABG, dosage and application of ACBT, its preventive role in postoperative pulmonary complications (PPCs), and its effects on respiratory and functional outcomes. The results of this review are expected to enhance clinicians' insight into selecting physical therapy to prevent PPCs. Pulmonary complications, including atelectasis and impaired gas exchange, are common after CABG and are primarily associated with anesthesia, surgical trauma, systemic inflammatory response, and impaired airway clearance. ACBT, consisting of breathing control, thoracic expansion, and forced expiration techniques, is a structured, non-invasive intervention designed to mobilize secretions and improve ventilation. It is typically applied 2-3 times per day over 2-5 days and often combined with incentive spirometry and conventional chest physiotherapy. The reviewed studies suggest that ACBT enhances oxygenation, improves lung volumes, and increases functional capacity. Additionally, ACBT helps reduce postoperative pain and dyspnea, contributing to overall recovery without reported adverse events. To conclude, ACBT is a safe, practical, and effective physiotherapeutic approach to support postoperative pulmonary recovery in CABG patients. Further well-designed trials are needed to validate and standardize its clinical use.