Coronary Artery Bypass Graft Surgery (CABG)

This prospective observational study evaluates the association between intraoperative mechanical power (MP) - a composite measure of the total energy delivered to the lungs during mechanical ventilation - and postoperative pulmonary complications (PPCs) and prolonged mechanical ventilation in adult patients undergoing elective coronary artery bypass graft (CABG) surgery with cardiopulmonary bypass (CPB). Intraoperative ventilatory parameters including tidal volume, respiratory rate, airway pressures, and PEEP will be recorded and used to calculate MP and driving pressure (DP). No additional interventions will be applied beyond standard clinical care.

Coronary artery bypass graft (CABG) surgery is the commonest type of heart operation performed. During this, arteries or veins (termed 'grafts') are used to supply blood around blockages within the blood vessels that supply the heart. Unfortunately, these grafts can sometimes fail, and patients can also experience complications like heart attacks and strokes, after surgery. It is known that vein grafts are more likely to narrow over time. Additionally, treating vein graft failure is very challenging, as repeat surgery is riskier and procedures to stent open the veins can also fail. However, it is not fully understood why these complications occur. In this study, the investigators will use an imaging technique called a total-body Positron Emission Tomography (PET) scan. This uses special radioactive dyes (radiotracers) to look at what is happening inside vein grafts. With this technique, the investigators will also be able to see what is happening to the heart, brain and wider parts of the body after CABG surgery. This study will aim to recruit 70 participants in total (maximum 150). 40 (maximum of 120) of these participants will have recently undergone CABG surgery and received ≥1 vein graft. The remaining 30 will have undergone CABG surgery ≥5 years ago and will have symptoms suggestive of vein graft failure. The study will last a total of 36 months and will involve participants undertaking the following assessments: 1. Total-body Positron Emission Tomography and Computed Tomography (PET-CT) scan 2. Ultrasound scan of the heart (echocardiogram) 3. A blood test - up to four tablespoons (60 mL) of blood will be taken for immediate testing and the remainder will be stored for future ethically approved studies.

This methodological study aims to determine the level of agreement between nurses and an artificial intelligence system (ChatGPT-4.0) in providing scenario-based discharge education for patients who have undergone coronary artery bypass graft (CABG) surgery. Thirty standardized patient scenarios representing different demographic, clinical, and psychosocial characteristics will be used. For each scenario, both expert nurses and ChatGPT-4.0 will prepare discharge education content based on six main domains and twenty-four subtopics identified from the literature and clinical guidelines. The educational materials will be independently evaluated by two blinded reviewers in terms of content accuracy, completeness, scientific consistency, and clarity of language. Agreement between nurses and AI-generated content will be analyzed using Cohen's Kappa coefficient and Fisher's Exact Test. The findings are expected to provide evidence for the reliability and applicability of AI-assisted discharge education systems in cardiac surgery nursing practice.

This study is planned as a randomized controlled experimental study to determine the effect of progressive relaxation exercises applied before mobilization on pain, anxiety and physiological parameters in patients undergoing coronary artery bypass graft surgery.