Risk factors for postoperative hypoxemia in patients with Stanford type A aortic dissection

Postoperative hypoxemia is quite common in patients with Stanford type A aortic dissection (STAAD) and is associated with poor clinical outcomes. However, there is no method to predict this potentially life-threatening complication. This study aims to identify the risk factors for postoperative hypoxemia in patients with Stanford type A aortic dissection, optimize perioperative management protocols, reduce the incidence of postoperative complications, and decrease patient mortality. Retrospective case–control study. A retrospective analysis was conducted on 206 patients diagnosed with Stanford type A aortic dissection in the Department of Cardiovascular Surgery of our hospital from January 2023 to December 2025. All patients underwent Sun's procedure. Among them, 132 were male, aged 32–76 years, with a mean age of (54.8 ± 10.9) years, and the time from onset to surgical treatment was less than 7 days. Hypoxemia was defined as arterial partial pressure of oxygen (PaO 2 )/fraction of inspired oxygen (FiO 2 ) less than 200 mmHg in arterial blood gas within 48 h postoperatively. Patients were divided into hypoxemia group (PaO 2 /FiO 2 < 200 mmHg) and non-hypoxemia group (PaO 2 /FiO 2 ≥ 200 mmHg) based on the presence of hypoxemia within 48 h postoperatively. Preoperative, intraoperative, and postoperative clinical data were compared between the two groups. Univariate analysis and multivariate logistic regression analysis were used to identify independent risk factors for postoperative hypoxemia in Stanford type A aortic dissection, aiming to develop individualized prevention and treatment strategies and improve patient prognosis. Among the 206 patients, 86 cases developed postoperative hypoxemia, with an incidence rate of 41.75%. Univariate analysis showed that risk factors for postoperative hypoxemia in patients with Stanford type A aortic dissection included preoperative total white blood cells (TWBC), operative time, deep hypothermic circulatory arrest (DHCA) time, postoperative mechanical ventilation time, intensive care unit (ICU) stay time, and postoperative hemodialysis, with statistical significance ( P < 0.05). Multivariate logistic regression analysis revealed that preoperative total white blood cell count > 10 × 10 9 /L, deep hypothermic circulatory arrest time were independent risk factors for postoperative hypoxemia. Preoperative total white blood cell count > 10 × 10 9 /L, deep hypothermic circulatory arrest time are independent risk factors for postoperative hypoxemia in Stanford type A aortic dissection. Clinical practice should strengthen preoperative infection control, optimize extracorporeal circulation strategies, and emphasize perioperative respiratory management to reduce the incidence of postoperative hypoxemia.