Objective: To characterize perioperative dynamic changes in immune-cell phenotypes and inflammatory cytokines in patients undergoing CPB (cardiopulmonary bypass) cardiac surgery, and to explore their associations with postoperative outcomes. Methods: In this prospective cohort study, 120 adult patients who underwent elective cardiac surgery under CPB at West China Hospital from May 2022 to March 2023 were enrolled. Perioperative immune-cell phenotypes and concentrations of 40 inflammation-related cytokines were measured. The primary outcomes were the sequential organ failure assessment (SOFA) score at 24 h after surgery and ΔSOFA (the peak SOFA score within 48 h after surgery minus the preoperative SOFA score). Secondary outcomes included major adverse cardiovascular events (MACE), acute kidney injury (AKI), respiratory failure, severe liver injury, and infection. Results: The mean age of enrolled patients was 57±10 years. Of these, 52% (62/120) were male and 90% (108/120) underwent valve surgery. During the rewarming to the end of CPB, neutrophil counts rapidly increased (7.39×10 /L vs preoperative 3.07×10 /L, P<0.001), with significant upregulation of CD11b (7.30×10 /L vs preoperative 3.05×10 /L, P<0.001) and CD54 (7.15×10 /L vs preoperative 2.99×10 /L, P<0.001). Lymphocyte counts increased at the end of CPB (1.75×10 /L vs preoperative 1.12×10 /L, P<0.001) but decreased significantly at 24 h after surgery (0.59×10 /L vs preoperative 1.12×10 /L, P<0.001). Plasma analysis showed that multiple pro-inflammatory cytokines increased during CPB and remained elevated up to 24 h after surgery; five chemokines and the anti-inflammatory cytokine IL-10 peaked at the end of CPB. The SOFA score increased from 1 (1, 2) preoperatively to 7 (5, 10) at 24 h after surgery, with a ΔSOFA of 6 (4, 8). Within 30 days after surgery, 48 patients (40.0%) developed AKI, 17 (14.2%) developed infection, 4 (3.3%) developed severe liver injury, 3 (2.5%) developed respiratory failure, and 3 (2.5%) experienced MACE. During the 2-year follow-up, 8 patients (6.7%) experienced MACE and 5 (4.2%) died. Conclusion: Multi-organ dysfunction is common after cardiac surgery under CPB (median ΔSOFA, 6), accompanied by perioperative activation of multiple immune-cell subsets and upregulation of pro-inflammatory, anti-inflammatory, and chemotactic mediators. This study provides data-driven evidence and research clues for further investigation of the associations between CPB-related immune perturbations and postoperative organ dysfunction and clinical outcomes.

[Objective] To explore the relationship between neutrophil activation under cardiopulmonary bypass (CPB) and the incidence of cardiac surgery-associated acute kidney injury (CS-AKI). [Methods] This prospective cohort study enrolled adult patients who scheduled for cardiac surgery under CPB at West China Hospital between May 1, 2022 and March 31, 2023. The primary outcome was acute kidney injury (AKI). Blood samples (5 mL) were obtained from the central vein before surgery, at rewarming, at the end of CPB, and 24 hours after surgery. Neutrophils were labeled with CD11b, CD54 and other markers. To assess the effect of neutrophils activation on AKI, propensity score matching (PSM) was employed to equilibrate covariates between the groups. [Results] A total of 120 patients included into the study, and 17 (14.2%) developed AKI. Both CD11b⁺ and CD54⁺ neutrophils significantly increased during the rewarming phase and the increases were kept until 24 hours after surgery. During rewarming, the numbers of CD11b⁺ neutrophils were significantly higher in AKI compared to non-AKI (4.71×10⁹/L vs 3.31×10⁹/L, Z=-2.14, P<0.05). Similarly, the CD54⁺ neutrophils counts were also significantly higher in AKI than in non-AKI before surgery (2.75×10⁹/L vs 1.79×10⁹/L, Z=-2.99, P<0.05), during rewarming (3.12×10⁹/L vs 1.62×10⁹/L, Z=-4.34, P<0.05), and at the end of CPB (4.28×10⁹/L vs 2.14×10⁹/L, Z=-3.91, P<0.05). An analysis of 32 matched patients (16 in each group) revealed that CD11b⁺ and CD54⁺ neutrophil levels of AKI were 1.74 folds (4.83×10⁹/L vs 2.77×10⁹/L, Z=-2.72, P<0.05) and 2.34 folds (3.32×10⁹/L vs 1.42×10⁹/L, Z=-4.12, P<0.05), respectively, of non-AKI at rewarming phase. [Conclusion] Neutrophils are activated during CPB, and they can be identified by CD11b/CD54 markers. The activated neutrophils of AKI patients are approximately 2 folds of non-AKI during the rewarming phase, with disparity reached peak between groups during rewarming. These findings suggest the removal of 50% of activated neutrophils during the rewarming phase may be effective to reduce the risk of AKI.

Objective     To explore the clinical effect of hemoperfusion (HP) in cardiopulmonary bypass (CPB) on postoperative inflammation in patients with acute type A aortic dissection (AAD). Methods    Adult patients with AAD who planned to undergo total aortic arch replacement from July 2020 to November 2021 were continuously enrolled in our heart center. Patients were randomly divided into a HP group and a control (C) group. The HP group was treated with disposable HP device (Model: HA380, Zhuhai Jafron Biomedical, China) in CPB during the operation. Results    Finally,  70 patients were included with 59 males and 11 females at an age range of 21-67 years. There were 35 patients in both groups. In this study, 3 patients died within 3 days after surgery, 2 in the HP group and 1 in the C group, and the remaining 67 patients survived to the follow-up end point (30 days after surgery). There was no statistical difference in preoperative baseline data, operative method, CPB time, block time, or other intraoperative data between the two groups. Blood product dosage, intubation time, hospital stays, and hospitalization expenses were similar between the two groups. Intraoperative hemoglobin (82.70±2.31 g/L vs. 82.50±1.75 g/L, P=0.954] and platelet concentration [(77.87±7.99)×109/L vs.(89.17±9.99)×109/L, P=0.384] were not statistically different between the HP group and C group. In the HP group, postoperative (ICU-12 h) interleukin-6 (IL-6) [338.14 (128.00, 450.70) pg/mL vs. 435.75 (180.50, 537.00) pg/mL, P=0.373], IL-8 [35.04 (18.02, 40.35) pg/mL vs. 43.50 (17.70, 59.95) pg/mL, P=0.383], and IL-10 [21.19 (6.46, 23.50) pg/mL vs. 43.41 (6.34, 50.80) pg/mL, P=0.537] were slightly lower than those in the C group, and the difference was not statistically different. The incidences of pulmonary infection (0.00% vs. 11.76%, P=0.042) and liver injury (2.94% vs. 20.58%, P=0.027) in the HP group were significantly lower than those in the C group, and the incidence of other postoperative complications, such as arrhythmia, nervous system complications and urinary system complications, showed no statistical difference between the two groups. Conclusion     HP therapy in CPB is safe, but its effect on reducing postoperative inflammatory factors, postoperative inflammatory reactions and postoperative complications in the patients with AAD is limited, and it may be of application value to some high-risk patients with lung and liver injury.