Risk factors for acute kidney injury in an enhanced recovery pathway for colorectal surgery

Purposes: Enhanced recovery pathways (ERPs) have been disseminated worldwide to improve the perioperative patient outcomes while lowering direct healthcare costs. Recent evidence has revealed a potential association between ERPs for colorectal surgery and acute kidney injury (AKI). We, therefore, sought to identify the risk factors associated with postoperative AKI among patients in an ERP for colorectal surgery. Methods: We analyzed the data resulting from a large multicenter, prospective cohort study of patients in an ERP for colorectal surgery. A multivariable analysis was performed to identify factors independently associated with postoperative AKI. The receiver operating characteristic (ROC) curves and contour representations were plotted for the diagnostic prediction analysis. Results: Among those patients included in the analysis (n = 1652), the overall incidence of postoperative AKI was 7.7% (95% CI 6.5–9.1%). After adjustment, the independent risk factors for AKI included age > 60 (OR 1.03, 95% CI 1.01–1.05), male gender (OR 2.33, 95% CI 1.36–4.02), ASA III-IV (OR 2.43, 95% CI 1.39–4.26), CKD (OR 2.45, 95% CI 1.42–4.23), open surgical approach (OR 2.62, 95% CI 1.63–4.21) and serum albumin < 3.5 g/dL (OR 1.68, 95% CI 1.02–2.79). An ROC analysis revealed that the composite of albumin, creatinine and age was a strong predictor of postoperative AKI [area under the curve (AUC) 0.756; 95% CI 0.705–0.808]. Conclusion: Postoperative AKI is common in the setting of ERPs for colorectal surgery and it is associated with a poor clinical outcome. Of those characteristics associated with postoperative AKI, one modifiable factor is a low preoperative albumin level. Screening for malnourished patients or optimizing the nutritional status may be a useful preoperative intervention to prevent postoperative AKI and associated complications.