Carotid sinus nerve blockade during carotid surgery: a randomised controlled trial

Area of Science:

• Cardiovascular Surgery
• Anesthesiology
• Neurosurgery

Background:

• Carotid endarterectomy (CEA) is a surgical procedure to remove plaque from the carotid artery.
• Blood pressure lability can occur post-CEA, potentially due to alterations in carotid sinus nerve function.
• Lignocaine (LA) is a local anesthetic that could theoretically modulate nerve activity.

Purpose of the Study:

• To investigate the efficacy of carotid sinus nerve infiltration with lignocaine in reducing blood pressure lability following CEA.
• To compare the effects of lignocaine, placebo, and nerve excision on blood pressure control and variability post-CEA.

Main Methods:

• Prospective, randomized, double-blind, controlled trial involving 80 patients undergoing CEA.
• Lignocaine or saline placebo was infiltrated around the carotid sinus nerve after initial dissection.
• Blood pressure was monitored continuously via intra-arterial cannula and intermittently manually for 24 hours post-procedure.

Main Results:

• Carotid sinus nerve excision led to significantly higher systolic and diastolic pressures compared to lignocaine or placebo groups.
• Nerve excision also resulted in greater blood pressure variability than lignocaine or placebo.
• Normotensive patients receiving lignocaine showed reduced diastolic pressure and variability, but pulse pressure was unaffected.

Conclusions:

• Lignocaine infiltration of the carotid sinus nerve offers no significant benefit for blood pressure lability in patients with treated hypertension post-CEA.
• Marginal benefits were observed in normotensive patients, but preserving the carotid sinus nerve is paramount.
• The study emphasizes the importance of nerve preservation over anesthetic infiltration for managing post-CEA hemodynamics.