Each year, over four million patients die within 30 days after surgery, accounting for 7.7% of global deaths. Due to its unique nature, cardiac surgery carries a significantly higher risk of perioperative complications and long-term mortality compared to non-cardiac surgeries. Therefore, the identification, management, and prevention of perioperative complications in cardiac surgery have long been a clinical focus. Common manifestations of perioperative organ injury include neurological complications, acute kidney injury, respiratory failure, gastrointestinal dysfunction, and liver injury. This study aims to explore the association between preoperative lifestyle and postoperative complications in cardiac surgery, as well as their interaction with clinical characteristics, in order to facilitate the prediction and prevention of perioperative complications. This retrospective cohort study plans to include adult patients undergoing elective cardiac surgery as the object of study. Different preoperative lifestyle habits will be considered as exposure factors to investigate the relationships between these exposure factors and the occurrence of major organ complications after cardiac surgery.

The risk of death and major complications in patients undergoing general anesthesia is less than 1%, thanks to the implementation of clinical practice guidelines and checklists, as well as advancements in training, medications, monitoring devices, and equipment. Consequently, the safety of anesthesia has steadily improved over the past century. However, a recent assessment in Europe and the United States indicates that the overall postoperative mortality rate remains higher than expected and is considered the third leading cause of death globally, following ischemic heart disease and cancer. This statistical result should be noted, as perioperative deaths are multifactorial and it is challenging to clearly distinguish between surgery-related deaths and those attributed to preoperative comorbidities. Each year, over four million patients die within 30 days after surgery, accounting for 7.7% of global deaths.

Due to its unique characteristics, cardiac surgery carries a significantly higher risk of perioperative complications and long-term mortality compared to non-cardiac surgeries. Therefore, the identification, management, and prevention of perioperative complications in cardiac surgery have long been a clinical focus. Integrating surgical and patient-related risk factors in a personalized manner before, during, and after surgery can improve patient outcomes, as exemplified by Enhanced Recovery After Surgery (ERAS) protocols. However, despite improvements in all preventive measures, acute organ injury remains a common complication and a significant risk factor for morbidity and mortality in cardiac surgery patients. Common manifestations of perioperative organ injury include neurological complications, acute kidney injury (AKI), respiratory failure, gastrointestinal dysfunction, and liver injury.

Although much beneficial work has been done regarding the prevention and identification of perioperative complications in cardiac surgery, there is currently limited research on the impact of patients' preoperative medical history, personal history, and comorbidities on the occurrence and prediction of perioperative complications in cardiac surgery. This study focuses on exploring the association between preoperative lifestyle and postoperative complications in cardiac surgery. Additionally, the study will examine the interaction between preoperative laboratory tests and examinations, intraoperative anesthetic medication and vital sign monitoring, and preoperative lifestyle factors.

1. Inclusion Criteria:

1. Age ≥ 18 years old.
2. Patients scheduled for elective cardiac surgery.
3. Patients who received medical care at hospital from January 2018 to November 2022.

2.Exclusion Criteria:

1. Pregnant women.
2. Patients whose preoperative examinations indicated they had already met the diagnostic criteria for acute kidney injury (AKI) or acute respiratory distress syndrome (ARDS).
3. Patients with severe preoperative abnormalities in liver or kidney function.
4. Patients with more than 10% missing data in their basic clinical information.
5. Patients with mental disorders.

Adult patients (age ≥18 years) who underwent cardiac surgery with cardiopulmonary bypass in a large-scale comprehensive hospital between January 1, 2019 and October 31, 2023, were included.

The relevant data need to be kept confidential.