Electrical impedance tomography (EIT) is an emerging medical imaging technology characterized by its non-invasive nature, absence of ionizing radiation, real-time dynamic imaging capability, low cost, and portability. In recent years, significant progress has been made in the application of EIT for perioperative respiratory management in adult major surgeries, particularly in the context of postoperative pulmonary complications. This review focuses on adult cardiac surgery patients and explores the clinical value of EIT in addressing extracorporeal circulation-related lung injury, managing one-lung ventilation, and enabling early detection of postoperative complications (such as atelectasis, pneumothorax). It also discusses EIT’s core functions in perioperative monitoring and its added value in the context of cardiac surgery, providing insights for precision and personalized respiratory management.