Subanesthetic ketamine infusion in the postoperative period as a means of cerebral protection in children undergoing surgical correction of congenital heart defects: a prospective randomized study

INTRODUCTION: The world literature describes the cerebroprotective properties of ketamine when used in minimal doses, which is due to its effect on NMDA receptors and inhibition of damage to the neurovascular unit. However, there is a lack of research on the use of ketamine for cerebroprotection in pediatric populations and cardiac surgery. OBJECTIVES: To establish the safety and effectiveness of ketamine infusion for cerebroprotection in children in the postoperative period during cardiac surgery. MATERIAL AND METHODS: The study included 45 children aged from 1 to 60 months and weighing from 3.5 to 20 kg, who underwent surgical correction of atrial or ventricular septal defect of the heart under artificial circulation. Patients were randomized into a study group or a control group. In the study group, upon completion, patients received a ketamine infusion at a dose of 0.1 mg/kg/hour for 16 h. To establish the effectiveness of cerebroprotection, serum markers of damage to the neurovascular unit were used: protein S100-β, neuron-specific enolase (NSE), glial fibrillary acidic protein (GFAP), occludin, claudin-1. Blood sampling for marker analysis was carried out at three control points: before the start of the operation, immediately after completion of artificial circulation and 16 hours after completion of the operation. RESULTS: Al studied factors in the intra- and postoperative period did not differ significantly between groups. When analyzing markers of damage to a neurovascular unit, their maximum concentration was revealed at the second control point. For the NSE marker, a lower level was found in the group using ketamine — 16.52 [11.61–18.8] and 21.37 [17.78–28.74] ng/ml (p = 0.0019). CONCLUSIONS: The safety of using ketamine infusion in the postoperative period at a dose of 0.1 mg/kg/hour was revealed. Among all markers used, NSE serum concentrations were statistically significantly lower in the ketamine group.