Non-Intubated Anesthesia for Adult Heart Transplantation

Inclusion Criteria: Age 18 years or older, regardless of sex. Listed for heart transplantation and scheduled to undergo isolated orthotopic heart transplantation. Able to breathe spontaneously without ongoing dependence on preoperative invasive mechanical ventilation. Perioperative anesthesia, surgical, intensive care unit, and follow-up data can be collected as required by the study protocol. Considered eligible for either NISVA or conventional endotracheal anesthesia following multidisciplinary assessment by the heart transplant surgery, anesthesia, cardiopulmonary bypass, and intensive care teams. Relatively stable vital signs after appropriate treatment and able to complete perioperative assessments and postoperative follow-up. Voluntary participation and written informed consent provided by the participant or the participant's legally authorized representative. Exclusion Criteria: Previous solid-organ transplantation that may substantially affect the assessment of perioperative outcomes for the current transplantation. Planned combined organ transplantation, including combined heart-kidney, heart-liver, or heart-lung transplantation. Complex anatomy associated with adult congenital heart disease that would substantially alter the surgical procedure or anesthetic management and is considered unsuitable for enrollment by the investigator. Preoperative endotracheal intubation or ongoing dependence on invasive mechanical ventilation. Severe pulmonary infection, severe respiratory failure, significant pulmonary edema, severe hypercapnia, or inability to tolerate a spontaneous ventilation anesthesia strategy, as determined by the study team. Severe pulmonary hypertension, severe right heart failure, or severely impaired baseline right ventricular function considered to present an unacceptably high risk for NISVA. Severe preoperative hemodynamic instability requiring high-dose vasoactive support, or use of mechanical circulatory support other than a durable left ventricular assist device or an intra-aortic balloon pump. Known difficult airway, high risk of aspiration, full stomach, gastric retention, severe gastroesophageal reflux, or another contraindication to supraglottic airway use. Estimated glomerular filtration rate below 40 mL/min/1.73 m², need for dialysis or ultrafiltration, or rapidly progressive renal dysfunction. Known liver disease-related coagulopathy, severe hepatic failure, or heparin-induced thrombocytopenia. A systemic disease that may substantially affect transplantation outcomes, including systemic lupus erythematosus, sarcoidosis, or amyloidosis. Active sepsis or a positive blood culture before surgery. ABO-incompatible transplantation. Ongoing pretransplant desensitization therapy, including peri-transplant plasma exchange or another treatment that may substantially affect inflammatory, immunologic, or outcome assessments. Concurrent participation in another interventional transplantation-related clinical trial that may affect the results of this study. Pregnancy or breastfeeding. Inability to understand the study, inability to complete the informed consent process, or considered unsuitable for enrollment by the investigator.