The cardiorespiratory system integrates systemic and pulmonary circulation while ensuring adequate oxygenation of the body at rest and during exercise. In addition to chronic respiratory problems that mainly affect the lungs, airways and pulmonary vascular system, respiratory capacity and respiratory muscle strength can be negatively affected in a wide spectrum including cardiac diseases, surgeries, neuromuscular diseases, obesity, long-term bed rest, aging and inactivity. Weakness of the respiratory muscles causes important secondary consequences by causing the increased respiratory demands not to be met during physical activity. It has been reported that respiratory muscle training applied within the scope of pre-operative and post-operative cardiac rehabilitation program is beneficial in terms of increasing respiratory functions, reducing the risk of post-operative complications and length of stay. Respiratory muscle training is known to have many potential beneficial effects on patients undergoing cardiac surgery. Different methods and devices are used to improve and develop the functions of the inspiratory and expiratory muscles and each training method and device has differences. Therefore, it is thought that examining the clinical effects of using a personalized breathing exercise device on respiratory functions, respiratory muscle strength and functional capacity in individuals who have undergone cardiac surgery will contribute to the literature.

Breathing exercises can be applied specifically to different segments of the lungs, increasing collateral ventilation and helping mobilize secretions. Chronic respiratory diseases, rib cage deformities, neuromuscular diseases that cause breathing problems, lung transplant or lung surgery patients in the pre-operative and post-operative period, cancer patients, heart failure patients and cardiovascular surgery patients, and those whose quality of life is impaired due to shortness of breath. People are known to be groups that benefit from breathing exercises. Breathing exercises have been shown to be effective in preserving respiratory function and preventing or reducing respiratory complications in all of these conditions. It has been reported that respiratory muscle training applied within the scope of pre- and post-operative cardiac rehabilitation programs is beneficial in increasing respiratory functions and reducing the risk of postoperative complications and length of stay. Respiratory muscle training is known to have many potential beneficial effects on patients undergoing cardiac surgery. Different methods and devices are used to improve and develop the functions of inspiratory and expiratory muscles, and each training method and device has differences. For this reason, the respiratory exercise device to be developed is aimed to be a device that can be shaped according to the desired purpose, has visual feedback, and can combine multiple respiratory muscle training methods. The device is thought to play an active role in rehabilitating complications such as lung ventilation and respiratory muscle weakness, which are frequently affected in patients after major surgery such as cardiac surgery. Therefore, it is thought that examining the clinical effects of using a personalized breathing exercise device on respiratory functions, respiratory muscle strength, and functional capacity in individuals who have undergone cardiac surgery will contribute to the literature.

Inclusion criteria

• Individuals with New York Heart Association Functional Class I or II who are scheduled to undergo elective coronary artery bypass graft surgery, aortic valve replacement, mitral valve replacement, or combined surgery of aortic and mitral valve replacement
• Individuals who are planning to undergo surgery with the median sternotomy technique
• Individuals with Mini-Mental State Score >24

Exclusion criteria

• Individuals with uncontrolled arrhythmia, unstable angina pectoris, uncontrolled hypertension
• Individuals with accompanying chronic respiratory disease
• Individuals with accompanying neuromuscular or orthopedic/musculoskeletal limitations
• Individuals with a history of spontaneous or trauma-related pneumothorax
• Individuals with middle ear-related pathologies (such as tympanic membrane rupture otitis)
• Cases with thorax drains in the ward
• Individuals who stayed in the intensive care unit for ≥ 4 days in the postoperative period
• Individuals who have had another surgery in the last six months

The assessor will be blind to the group allocation and participants will be blind to the intervention.