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Updated: Jul 30, 2026
05:30
Controlled Cortical Impact Model for Traumatic Brain Injury
Published on: August 5, 2014
Head injury: clonidine decreases plasma catecholamines.
D Payen1, L Quintin, P Plaisance
1Département d'Anesthésie-Réanimation, Hôpital Universitaire Lariboisière, Paris, France.
Critical Care Medicine
|April 1, 1990
Summary
Clonidine administration reduced sympathetic overactivity in head injury patients by lowering norepinephrine and epinephrine levels. This treatment maintained cerebral blood flow, suggesting potential benefits for managing head injuries.
Area of Science:
- Neuroscience
- Pharmacology
- Critical Care Medicine
Background:
- Head injury can lead to sympathetic overactivity, potentially worsening outcomes.
- Cerebral hemodynamics are critical for recovery after head trauma.
Purpose of the Study:
- To investigate the effect of clonidine on sympathetic activity and cerebral hemodynamics in patients with head injury.
Main Methods:
- Seven patients with recent head injury received intravenous clonidine (2.5 µg/kg).
- Plasma norepinephrine and epinephrine levels were measured.
- Common carotid blood flow and diastolic blood flow were assessed using pulsed Doppler to evaluate cerebral perfusion.
Main Results:
- Clonidine significantly reduced plasma norepinephrine and normalized plasma epinephrine levels (p < .05).
- No significant changes were observed in common carotid blood flow or diastolic blood flow, indicating preserved global cerebral perfusion.
- The drug's action is likely mediated via alpha 2-adrenoceptors in the rostral ventrolateral medulla.
Conclusions:
- Clonidine effectively reduces sympathetic overactivity in the context of head injury.
- The drug appears to maintain stable cephalic hemodynamics, which is crucial for managing head trauma.
- These findings suggest clonidine may be a valuable therapeutic option for head injury management.
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