Autonomic Hyperactivity

  • show all 0 hide
This is an excerpt from the content

Definition

Autonomic hyperactivity may manifest as sympathetic hyperactivity, parasympathetic hyperactivity or both.

These most often occur in the context of acute brain injury resulting in loss of inhibition or irritation of excitatory foci within the central autonomic network.

Centrally mediated sympathetic hyperactivity is also seen in chronic spinal cord injury (Autonomic dysreflexia).

Sympathetic or parasympathetic hyperactivity are also occasional features of Guillain-Barré syndrome.

Patients may present with extraordinarily high blood pressure and heart rate – even a doubling of normal values – or conversely hypotension and bradycardia where vagal hyperactivity predominates.

These and other symptoms, such as salivary and bronchial hypersecretion, may place patients at immediate risk of cardiac or respiratory failure.

Autonomic Insufficiency

Guillain-Barré Syndrome