[Trigeminocardiac reflex in pituitary surgery. A prospective pilot study]

Area of Science:

• Neurosurgery
• Cardiovascular Physiology
• Neuroscience

Background:

• The trigeminocardiac reflex (TCR) is a brainstem reflex causing simultaneous drops in mean arterial pressure and heart rate.
• It is triggered by stimulation of the trigeminal nerve, a phenomenon increasingly recognized in neurosurgery.

Purpose of the Study:

• To prospectively determine the incidence of TCR during trans-sphenoidal surgery.
• To identify potential predisposing factors for TCR.
• To investigate biomarkers related to ischemic events and neuroprotection following TCR.

Main Methods:

• Prospective registration of TCR during trans-sphenoidal surgeries.
• Measurement of biomarkers, including C-reactive protein, tumor necrosis factor A, and noradrenalin.
• Correlation analysis between biomarkers, tumor size, and TCR occurrence.

Main Results:

• TCR occurred in 7.5% of patients after cavernous sinus exposure and 2.5% during nasal mucosa preparation.
• No permanent cardiovascular damage or adverse postoperative outcomes were observed.
• A trend towards lower C-reactive protein levels post-TCR suggested potential neuroprotective cascades, though not definitively proven.

Conclusions:

• The extent of neuroprotective mechanisms activated by TCR remains unclear, despite an apparent trend.
• Prophylactic or therapeutic use of atropine is not justified due to potential adverse effects and the reflex arc.
• Further research is needed to fully elucidate the neuroprotective aspects of TCR.