Association of Perioperative Hyperchloremia and Hyperchloremic Metabolic Acidosis with Acute Kidney Injury After Craniotomy for Intracranial Hemorrhage.

Background: The present study evaluated the relationships among perioperative hyperchloremic metabolic acidosis (HCA), hyperchloremia, and postoperative acute kidney injury (AKI) in patients who had undergone craniotomy for intracranial hemorrhage (ICH).

Methods: The present retrospective cohort study included adult patients who had undergone craniotomy for traumatic or spontaneous ICH from January 2005 to December 2017. The association of perioperative hyperchloremia (serum chloride [Cl] >110 mmol/L during postoperative days 0-3), an increase in Cl levels (maximum Cl level in postoperative days 0-3 minus the baseline Cl level before surgery), and perioperative HCA (Cl >110 mmol/L; pH <7.35, with a bicarbonate level <24 mmol/L) with the incidence of AKI was analyzed using multivariable logistic regression analysis.

Results: A total of 968 patients were included. Of these patients, 117 (12.1%) had postoperative AKI. The multivariable logistic regression analysis showed that the development of HCA was associated with a 1.850-fold increase in the incidence of postoperative AKI (odds ratio [OR], 1.850; 95% confidence interval [CI], 1.102-3.106; P = 0.020). However, hyperchloremia was not significantly related to the incidence of postoperative AKI (P = 0.207). Additionally, the presence of hyperchloremia and an increase in Cl levels were both associated with an increased incidence of HCA (hyperchloremia group: OR, 2.162; 95% CI, 1.490-3.138; P < 0.001; 1-mmol/L increase in Cl level: OR, 1.035; 95% CI, 1.008-1.062; P = 0.011).

Conclusions: Perioperative HCA was independently related to an increased incidence of AKI after craniotomy for ICH. An increase in Cl levels and perioperative hyperchloremia were associated with increased development of HCA but were not significantly related to the development of postoperative AKI.