What are the autonomic manifestations that accompany severe brain injury?
In the initial phase of severe traumatic brain injury, dysautonomic manifestations are frequent.
The main features of this syndrome include marked agitation, diaphoresis, hyperthermia, hypertension, tachycardia, tachypnea, and dystonia of limbs.
Various names have been given to this complex of symptoms, including paroxysmal sympathetic storm, diencephalic seizures, hypothalamic-midbrain dysregulation syndrome, paroxysmal sympathetic hyperactivity, and paroxysmal autonomic instability with dystonia.
The pathophysiology of this syndrome seems to be related to the dysfunction of autonomic centers in the diencephalon (thalamus and hypothalamus) or their connections to cortical, subcortical, and brain stem loci that mediate autonomic function.
It has been suggested that a disinhibition phenomenon occurs, with loss of cortical and subcortical control of vegetative functions, including blood pressure and temperature.
First-line treatment options in the acute setting of the syndrome include opioids, gabapentin, benzodiazepines, centrally acting α-agonists and β-antagonists, and in refractory cases intrathecal baclofen.
