Open heart surgery is often associated with postoperative pulmonary complications, reduced lung expansion, dyspnea, and impaired cardiopulmonary function. Breathing exercises are commonly used after surgery to improve lung ventilation, enhance oxygenation, and support respiratory recovery. However, limited evidence is available comparing the effectiveness of segmental breathing exercises and active cycle breathing technique (ACBT) in patients after open heart surgery.

This randomized controlled trial will compare the effects of segmental breathing exercises and ACBT on dyspnea and cardiopulmonary parameters in adults undergoing open heart surgery. Participants will be randomly assigned to either the segmental breathing exercise group, the ACBT group, or the standard care group during the postoperative period following extubation.

Cardiopulmonary parameters, including oxygen saturation, respiratory rate, heart rate, and blood pressure, as well as dyspnea severity and postoperative pulmonary complications, will be assessed before and after the interventions.

The findings of this study may help identify the most effective breathing exercise technique for improving respiratory outcomes, reducing postoperative pulmonary complications, and supporting evidence-based postoperative rehabilitation after cardiac surgery.

This randomized clinical trial evaluates the effects of segmental breathing exercises (SBE) and active cycle breathing technique (ACBT) on dyspnea, cardiopulmonary parameters, and postoperative pulmonary complications in adults undergoing elective open-heart surgery with cardiopulmonary bypass.

Participants will be randomly assigned to one of three groups: segmental breathing exercises group, active cycle breathing technique group, or standard care group. Patients in the intervention groups will perform the assigned breathing exercises after extubation, including sessions conducted 1 hour and 6 hours post-intervention during the early postoperative period.

Cardiopulmonary parameters, including oxygen saturation, respiratory rate, heart rate, and blood pressure parameters, will be monitored throughout hospitalization. Dyspnea and postoperative pulmonary complications, including atelectasis and pneumonia, will also be assessed.

The primary purpose of this study is to determine the effectiveness of breathing exercise interventions in improving postoperative respiratory outcomes and reducing pulmonary complications after cardiac surgery. The study also aims to support evidence-based postoperative rehabilitation practices for healthcare professionals caring for patients after open-heart surgery.

Inclusion Criteria:

• Age 18-75 years.
• Scheduled for elective open-heart surgery.
• Can understand instructions and perform Segmental breathing and Active cycle breathing techniques.
• Stable preoperative hemodynamic condition.

Exclusion Criteria:

• Emergency cardiac surgeries.
• Patients with pre-existing severe pulmonary disease (e.g., COPD, asthma, restrictive lung disease, Atelectasis, and Tuberculosis).
• Neurological disorders affecting breathing effort.
• Patients with rib fractures, recent thoracic trauma, or contraindications for coughing maneuvers.
• Inability to provide informed consent (cognitive impairment, language barrier).

IPD will not be shared due to patient privacy and confidentiality concerns.