Relationship between perioperative plasma neutrophil gelatinase-associated lipocalin level and acute kidney injury after acute type A aortic dissection.

Background: Acute type A aortic dissection (ATAAD) is a prevalent and life-threatening emergency in cardiovascular surgery. Acute kidney injury (AKI) is a common perioperative complication of ATAAD. The mechanism of occurrence is multi-factor. The traditional assessment of renal function might be postponed and better biomarkers are needed to predict AKI. This study simultaneously evaluated perioperative plasma neutrophil gelatinase-associated lipocalin (NGAL) levels during ATAAD surgery to predict the risk of postoperative. Methods: Total of 104 ATAAD patients were included in this research. Blood samples were collected from the patients at different time points: before surgery (T1), at the end of hypothermic circulatory arrest (HCA) (T2), at the end of cardiopulmonary bypass (CPB) (T3), 24 hours post-operation (T4), and 48 hours post-operation (T5). The patients were grouped based on whether the AKI occurred after surgery, and we compared levels of plasma NGAL across different time points. Additionally, we constructed a multivariate logistic regression model using preoperative and intraoperative data from the patients, incorporating plasma NGAL as a predictor to assess its predictive capability. Results: Based on Kidney Disease: Improving Global Outcomes (KDIGO) criteria, the occurrence of AKI among the 104 ATAAD patients was found to be 39.4% (41 out of 104). Within this group, 12 patients were categorized as KDIGO stage 1, 11 as stage 2, and 18 as stage 3; additionally, 14 patients required continuous renal replacement therapy (CRRT). Plasma NGAL levels were elevated at all measured time points for AKI patients compared to non-AKI group. Subgroup analysis revealed that plasma NGAL levels in patients with severe AKI (sAKI) consistently exceeded those in mild AKI (mAKI) cases, while no significant difference was observed between mAKI and non-AKI groups. Plasma NGAL demonstrated predictive capability for sAKI at each time point, with an area under the curve (AUC) of 0.739 [95% confidence interval (CI): 0.616-0.861; P<0.001] recorded at T5. Independent risk factors for postoperative AKI in ATAAD patients included preoperative ejection fraction [odds ratio (OR): 0.90; 95% CI: 0.81-0.99; P=0.043], D-dimer level (OR: 1.05; 95% CI: 1.01-1.09; P=0.01), and plasma NGAL level (OR: 1.02; 95% CI: 1.01-1.04; P=0.01). Conclusions: The perioperative levels of plasma NGAL in patients who developed AKI after ATAAD were notably elevated compared to those without AKI. Furthermore, plasma NGAL demonstrated strong predictive capability for severe postoperative AKI.