To explore the factors related to hyperammonemia caused by perioperative valproate (VPA) use in neurosurgery and its effect on prognosis of patients.

Patients with intracranial lesions who were admitted to Neurosurgery Department of Xuanwu Hospital, Capital Medical University from March to June 2021 were selected. VPA was used during the perioperative period. The clinical data of patients were collected, including basic information, VPA dosage, duration, blood concentration and related complications. Related factors and complications of hyperammonemia caused by VPA were analyzed.

A total of 123 patients with intracranial lesions using VPA were included in this group, 42 patients (34.15%) developed hyperammonemia, among which 3 patients (2.44%) developed hyperammonia-encephalopathy. Univariate and multivariate Logistic regression analysis showed that body mass index (BMI) and steroid hormone use were independent risk factors for the occurrence of hyperammonemia (P<0.05). Among them, patients with high BMI and combined use of steroid hormones were more likely to develop hyperammonemia. The dosage, duration and blood concentration of VPA were not related to hyperammonemia, and the difference was not statistically significant (P>0.05). Hyperammonemia prolonged the treatment time and total hospital stay in ICU, which would affect the prognosis 30 d after discharge (P<0.05), but had no effect on the prognosis 90 d and 1 year after operation (P>0.05). Postoperative complications occurred in both hyperammonemia group and non hyperammonemia group, but the difference was not statistically significant (P>0.05).

VPA is relatively safe to prevent epileptic seizures during perioperative period of neurosurgery, but attention should be paid on the related complications, especially hyperammonemia. Neurosurgeons should pay close attention to the differentiation of consciousness disturbance caused by operation and high ammonia encephalopathy to avoid influencing clinical decision making.