A Review of Hypervolemic Hemodilution in Pediatric Neuroanesthesiology

Hypervolemic hemodilution (HVH) is a blood-sparing technique increasingly used in pediatric neuroanesthesiology, particularly during high-risk procedures such as craniosynostosis repair. By expanding intravascular volume with crystalloids or colloids before surgery, HVH dilutes red blood cell concentration, thereby reducing their loss due to bleeding, while maintaining cerebral oxygenation and hemodynamic stability. This approach is especially valuable in pediatric patients, who are more susceptible to transfusion-related complications due to their limited blood volume and immature immune systems. Compared to acute normovolemic hemodilution, HVH is simpler and equally effective when blood loss is anticipated to be moderate. However, its use requires careful monitoring, as HVH may affect intracranial pressure, cerebral autoregulation, and anesthetic pharmacokinetics. This review highlights the clinical applications, physiologic impacts, and safety considerations of HVH in pediatric neurosurgical care, while identifying gaps in current literature, such as the lack of long-term outcome data and high-quality comparative trials in pediatric patients.