Preoperative Neutrophil-Platelet Ratio as a Predictor of Acute Kidney Injury after Total Aortic Arch Replacement: A Retrospective Cohort Study

Background: Acute kidney injury (AKI) is a common complication following total aortic arch replacement (TAAR) in patients with acute type A aortic dissection (ATAAD), with inflammatory dysregulation contributing to its pathogenesis. This study aims to develop a predictive model that integrates neutrophil-to-lymphocyte ratio (NPR) with clinical risk factors to facilitate the early identification of high-risk patients, thereby enabling targeted interventions to mitigate AKI and enhance clinical outcomes. Methods: This research was a single-center, retrospective cohort study comprising 396 patients undergoing TAAR between July 2021 and March 2023 in China. Participants were categorized into AKI and non-AKI groups based on KDIGO criteria. ROC analysis was employed to assess the predictive capability of inflammatory markers for AKI. Significant predictors identified were incorporated into a multivariate logistic regression model, which was adjusted for potential confounding variables, to ascertain independent risk factors for AKI. Furthermore, a causal mediation analysis was performed. Results: ROC analysis identified NPR as the most robust predictor (AUC 0.660, p<0.001), surpassing both NLR and NLPR. Multivariable regression analysis confirmed that NPR (OR 1.20, 95%CI 1.10–1.30) and renal artery involvement (OR 1.68, 95% CI 1.36–2.09) were independent risk factors for AKI. Mediation models incorporate the interaction term, reveals that NPR serves as a negative moderator in the relationship between the involved renal artery (β=-0.044). Conclusions: Preoperative NPR demonstrated desirable predictive accuracy for AKI incidence following TAAR. The study further indicated that both renal artery involvement and NPR independently and significant increased AKI risk. while they negatively interact, renal artery involvement diminished the positive association between NPR and AKI, while an increase in NPR also reduced the exacerbating effect of renal artery involvement. These findings suggest potential targets for improving perioperative renal protection, though further validation and studies are needed. Clinical trial number： No. NCT05206032（Registered on December 1, 2021）