Perioperative complications of acute kidney injury (AKI) can seriously affect patient prognosis, with extremely high mortality and disability rates. The neurosurgical literature has reported that AKI increases the risk of death in patients with severe craniosynostosis. In craniotomy, the impact of AKI on the risk of death in patients within 30 days is not known. Vesela P. Kovacheva et al, Department of Anesthesiology, Brigham and Women’s Hospital, Boston, Massachusetts, USA, found that AKI does affect the outcome of patients undergoing craniotomy through a retrospective analysis of clinical data, with results published online in the November 2015 issue of Neurosurgery. A total of 1,656 patients with documented renal function test results underwent craniotomy at Brigham and Women’s Hospital or Massachusetts General Hospital from 1998 to 2011, with a mean age of 55 years, 63% male, and 75% white. AKI was graded by RIFLE criteria according to the multiple increase in blood creatinine over basal levels: risk, ≥1.5-fold increase in creatinine; injury, ≥2-fold increase in creatinine and failure, ≥3-fold increase in creatinine. The correlation between AKI and mortality was analyzed using mortality within 30 days as the primary outcome event. The risk, injury, and failure incidence of AKI in the RIFLE classification were 5.7%, 2.9%, and 1.3%, respectively. After eliminating the mortality influencing factors of age, sex, ethnicity, Deyo-Charlson index, trauma, acute respiratory failure, chronic kidney disease and intracranial hemorrhage, the ratio of the risk of death within 30 days due to AKI in the above 3 grades was 2.79 (95% CI 1.76-4.42), 7.65 (95% CI 4.16-14.07) and 14.41 ( 95% CI 5.51-37.64) (Table 1). In addition, patients also had a significantly higher risk of death during follow-up, 1.82 (95% CI 1.34-2.46), 3.37 (95% CI 2.36-4.81), and 5.06 (95% CI 2.99-8.58), corresponding to 3 different levels of AKI. The likelihood of readmission after AKI was also significantly increased compared to patients who did not experience AKI, with 2.8-fold, 7.7-fold and 14.4-fold for the 3 levels, respectively. Table 1, Risk of death within 30 days after craniotomy for different RIFLE levels of AKI. In conclusion, AKI complicating craniotomy can lead to increased mortality in patients. The severity of AKI in patients is positively correlated with the risk of death within 30 days, which requires high attention of clinicians.