Background: Neonates have a higher metabolic rate and an increased risk of perioperative hypoglycemia and lipolysis, but during anesthesia, both oxygen consumption and metabolic rate are decreased, and this may lead to reduced intraoperative glucose requirements. Objective: The objective of this prospective multicentre observational post-authorisation safety study was to evaluate the intraoperative use of a novel isotonic balanced electrolyte solution with a low glucose concentration of 1% (BS-G1) in neonates with a particular focus on changes in acid-base, electrolyte, and glucose concentrations. Methods: Following the local ethics committee approval, neonates with a postmenstrual age under 45 weeks and an ASA risk score of I-IV undergoing intraoperative administration of BS-G1 were enrolled. Patient demographics, the performed procedure, adverse drug reactions, hemodynamic data, and the results of blood gas analysis before and after infusion were documented with a focus on changes in acid-base, electrolyte, and glucose concentrations. Results: In 66 neonates (ASA I-IV; postmenstrual age 38 +/- 4, range 25-45 weeks; body weight 2.9 +/- 0.9, range 0.65-4.6 kg), the mean infusion rate was 10.4 +/- 3.2 (range 4.5-19.6) ml.kg(-1) h(-1) BS-G1. During the infusion, hemoglobin, hematocrit, bicarbonate, base excess, anion gap, strong ion difference, and calcium decreased, and chloride and glucose increased significantly within the physiological range. All other measured parameters including sodium and lactate remained stable. Neither hypoglycemia (glucose < 3 mM) nor hyperglycemia (glucose > 10 mM) was documented after BS-G1 infusion. No adverse drug reactions were reported. Conclusion: The study shows that the intraoperative use of an isotonic balanced electrolyte solution with 1% glucose and a mean infusion rate of 10 ml.kg(-1) h(-1) helps to avoid acid-base dysbalance, hyponatraemia, hypoglycemia, ketoacidosis, and hyperglycemia in surgical neonates. A careful intraoperative monitoring and adaptation of the infusion rate as needed is crucial because the glucose and fluid requirements may vary widely between subjects.
