Brainstem and Autonomic Nervous System Dysfunction: A Neurosurgical Point of View.

Central autonomic control nuclei and pathways are mainly integrated within the brainstem, especially in the medulla oblongata. Lesions within these structures can lead to central dysautonomia.Central autonomic control structures can be damaged by tumors, during surgery, or by other neurosurgical pathologies. These may elicit clinical or subclinical autonomic complications that can constitute a serious clinical problem.The authors present a broad review of the central autonomic nervous system, its possible dysfunctions, and the relation between neurosurgery and this "not-well-known system". Preliminary results of an autonomic study of brainstem lesions that is currently being carried out by the authors are also shown.

Autonomic dysfunction elicited by a medulla oblongata injury after fourth ventricle tumor surgery in a pediatric patient.

We report the case of a 9-year-old male patient with a recurrent fourth ventricle anaplastic ependymoma who developed severe arterial hypertension and blood pressure lability during and after surgery. A punctual bilateral lesion located within mid dorsal medulla oblongata caused by both infiltration and surgical resection was observed in postoperative MRI. Three years later, the patient remained neurologically stable but the family referred the presence of a chronic tachycardia as well as palpitations and sweating with flushing episodes related to environmental stress. On autonomic evaluation, an increase in sympathetic outflow with tachycardia together with orthostatic hypotension caused by baroreceptor reflex dysfunction was observed. We postulate that a bilateral injury to both nuclei of the solitary tract may have caused central dysautonomia.