Postoperative acute kidney injury in major abdominal surgery. Utility of the urinary biomarker [TIMP-2] × [IGFBP7] (NephroCheck™).

Background: The urinary biomarker [TIMP-2] × [IGFBP7] enables the prediction of postoperative acute kidney injury (PO-AKI). Our study aimed to assess the incidence of PO-AKI in high-risk patients undergoing major abdominal surgery and to evaluate the impact of implementing KDIGO renal optimization measures in those with renal stress identified by [TIMP-2]×[IGFBP7].

Materials and methods: This was a prospective study including 182 patients who underwent major abdominal surgery. Perioperative data, [TIMP-2] × [IGFBP7] levels, and the implementation of KDIGO renal protection strategies in the ICU were collected. Predictors of PO-AKI were identified through multivariate analysis.

Results: The overall incidence of PO-AKI was 25.3%, reaching 42.7% in ICU patients. [TIMP-2] × [IGFBP7] showed moderate predictive ability (AUROC = 0.74), with a PO-AKI incidence of 47.5% in patients with elevated levels. Despite the implementation of KDIGO measures in the ICU, the incidence of PO-AKI in patients with elevated [TIMP-2] × [IGFBP7] was 65.6%. In multivariate analysis, the main predictors of PO-AKI were elevated [TIMP-2] × [IGFBP7] (OR = 6.3; 95% CI: 2.6-15.6; p < 0.001), male sex (OR = 6.1; 95% CI: 1.9-19.6; p = 0.002), and ICU admission (OR = 4.5; 95% CI: 1.5-13.6; p = 0.009).

Conclusions: PO-AKI is common after major abdominal surgery, particularly in ICU patients. The [TIMP-2] × [IGFBP7] biomarker allows for early identification of at-risk patients, although the implementation of KDIGO measures in the ICU did not significantly reduce its incidence.