Regional anesthesia for carotid endarterectomy: a comparison between ropivacaine and levobupivacaine.

Background: This study compares ropivacaine and levobupivacaine when administered for cervical plexus block. The authors therefore compared the arterial pressure profile and the incidence of hypotension between drugs.
Methods: Forty-eight patients scheduled for carotid artery surgery (American Society of Anesthesiologists [ASA] 2-3) were randomly assigned to receive levobupivacaine or ropivacaine (24 patients each). Neurological status, arterial pressure profile and control of postoperative pain were the main observed parameters. All patients had severe carotid stenosis (>80%) and/or had suffered transient ischemic attacks (TIAs) or preoperative strokes. The same team performed anesthesia and surgery for carotid endarterectomy; the cervical block was performed according to Moore's technique.Arterial pressure, heart rate and S(a)O(2p) were monitored continuously with particular regard to T0 (baseline), T1 (immediately before carotid clamping), T2 (immediately before declamping) and T3 (at the end of the procedure). Hypotension was defined as the fall of arterial systolic pressure 30% below baseline or less than 100 mmHg.
Results: Arterial pressure fell significantly in both groups at T1 with respect to T0 (P<0.0001). Levobupivacaine patients showed higher mean arterial pressure on T0 (112+/-12 mmHg versus 103+/-7 mmHg; P<0.05), thus suggesting a more pronounced vasodilator effect, as confirmed by the larger drop of arterial diastolic pressure (P=0.007). An absolute 6% difference of hypotension-related drug was recorded with levobupivacaine (19%) as compared with ropivacaine (13%) (P=0.28).
Conclusions: Levobupivacaine has a greater vasodilatory effect than ropivacaine. Its higher incidence of hypotension, although not statistically significant, suggests ropivacaine as the drug of choice for cervical plexus block.