Preparation for Surgery on Supratentorial Low-Grade Gliomas in Children

The signs and symptoms of LGGs evolve slowly, so time can usually be taken to prepare a child for surgical treatment. 

Preoperative Orders

• Steroid and anticonvulsant premedication: Medications are given to decrease ICP and to deal with any seizure activity.

Anesthetic Considerations

Children are not “miniature adults.”  This pediatric aphorism is basic to planning surgery in children. LGGs require large hemispheric craniotomies with major subgaleal stripping with possible associated blood loss and a very long operating time.

• Perioperative monitoring: The basic perioperative monitoring practices should be expanded in children with hemispheric lesions, given the potential for heavy bleeding. Children have a limited functional reserve when facing the probable hypovolemia and significant blood loss involved with surgery.
• Specialized pediatric anesthesia: Anesthetic management should be handled in specialized pediatric units, as this practice has been demonstrated (14) to be beneficial in the management of supratentorial lesions.
• Cardiovascular support: Minimum support should include appropriate venous catheterization, central venous access, and invasive control of blood pressure. The difficulty of performing venous catheterization in very small patients and the increased time required to insert these catheters should be anticipated. No procedure of this type should be started before adequate vascular support and control have been attained.

Devices to Be Implanted

• Catheters and other devices for CSF drainage: Sometimes if there is hydrocephalus, the surgeon can implant a ventricular shunt or EVD.

Ancillary/Specialized Equipment Required for Surgery

• Multidisciplinary coordination: Coordination between truly multidisciplinary teams of surgeons, anesthesiologists, neurophysiologists, and the nursing staff is essential.  Systems that permit information distribution (imaging and data) in real time to the different operating room specialists contribute to success in this type of intervention.
• Neuromonitoring: An important problem for pediatric anesthesiologists is the patient who requires neuromonitoring of pathways such as the corticospinal tracks. These children require specialized neuroanesthetic techniques that should be coordinated with the anesthesia personnel prior to the surgery.
• Mapping of function: The localization of eloquent areas with preoperative imaging and intraoperative neurophysiological mapping has contributed to success in the resection of supratentorial glial lesions. Such functional studies are complicated in young children, however, since intrasurgical identification with a cooperative, awake patient is very difficult in children under 10 years of age without appropriate psychological preparation, while fMRI studies are quite complex and not widely available. Presurgical transcranial mapping of the eloquent areas is impossible in young children. It can be attempted intraoperatively but it is not always successful due to an infant’s and young child’s relative resistance to cortical stimulation.
• Neuronavigation makes it possible to perform smaller craniotomies, determine surgical trajectories that avoid injury, and decrease surgery time. Results (15) show that the combination of a navigator with microsurgery results in fewer long-term complications, sequelae, and, above all, longer survival times for patients with supratentorial astrocytomas than surgery with only a surgical microscope.
• Intrasurgical imaging: Intrasurgical MRI and CT, the fusion of MRI and ultrasound images with the navigation techniques, or the integration of multiple images and medical data are qualitative elements that doubtlessly lead to a greater degree of control over the resection, permitting fewer sequelae. This technology has made control over the tumor resection possible so as to avoid eloquent anatomical structures (16).