Comparison of two methodologies; ultrason guided perivascular regional anestesia of the internal carotid artery and deep cervical plexus block for carotid surgery

Abstract

The aim of this study was to determine a more effective and a more secure method by comparing the need of additional local anesthesia, incidence of complications and sedation need on patients undergoing carotid endarterectomy (CEA) associated with cervical plexus block and ultrasound guided perivascular regional anesthesia of the internal carotid artery. After approval of the Ethics Committee of the hospital, and patients’ informed consents were obtained, 58 patients were scheduled for elective CEA under regional anesthesia were randomly assigned to one of the two groups. Group perivascular (PV), at the level of the based of the carotid bifurcation, the needle was inserted at the lateral border of the sternocleidomastoid muscle and, guided by ultrasound, around the carotid artery, where prilocaine and bupivacaine ( 2% prilocaine 7.5 ml and 0.5% bupivacaine 7.5 ml) were injected. Group deep cervical plexus block (DCPB), the classical approach to a deep cervical plexus block was to perform separate injections at C2, C3 and C4, where prilocaine and bupivacaine ( totally 2% prilocaine 7.5 ml and 0.5% bupivacaine 7.5 ml) were injected. Also, both of two groups were to perform superficial cervical plexus block which was a subcutaneous blockade of the distinct nerves of the anterolateral neck. It involved puncturing the investing fascial layer before 2% prilocaine 7.5 ml and 0.5% bupivacaine 7.5 ml were injected. The members of both groups of PV and DCPB were in the same range of age, body weight and gender (respectively 66.6±6.8 years and 69.5±7.5 years, 79.2±15.1 kg and 73.9±9.7 kg, rate of male patient 46.7% and 53.3%, for all comparisons p>0.05). The satisfaction of the surgeon (4.41±0.73 and 4.55±0.68), anesthetist (4.69±0.60 and 4.52±0.83) and the patient (4.21±0.82 and 4.45±0.95) during the operation were identical (p>0.05). Both of the groups did not differ in the means of using additional local anesthesia (1% prilocaine) (respectively 7.97±8.52 mg and 7.24±11.07 mg, p=0.43), however Group PV required more midazolam compared to Group DCPB (respectively 1.06±0.81 mg and 0.43±0.69 mg, p=0,02) The complications of disfagia (13.8% and 17.2%) and shoulder movements (0% and 4.8%) related to applied block were similiar on both groups (respectively Grup DCPB and PV, p=0.78 and p=0.32) while the hoarseness was observed at a higher rate on Group PV (26.9%, CI 0.01-0.37 and 73.1%, CI 0.39-0.85, p=0.003). We conclude that the described ultrasound-guided perivascular anesthesia technique is effective for carotid artery surgery. The satisfaction of anesthesist, operator and the patient were similar on CEA associated with cervical plexus block and ultrasound guided perivascular regional anesthesia of the internal carotid artery. The required amount of midazolam was increased and hoarseness was observed more frequently on operations associated with USG block applications. 1. Ramachandran SK, Picton P, Shanks A, Dorje P, Pandit JJ: Comparison of intermediate vs subcutaneous cervical plexus block for carotid endarterectomy. BJA 107(2):157-163, 2011. 2. Pandit JJ, Satya-Krishna R, Gration P: Superficial or deep cervical plexus block for carotid endarterectomy: a systematic review of complications. BJA 99(2):159-169, 2007. 3. Augoustides JGT: Advances in the management of carotid artery disease: focus on recent evidence and guidelines. J Cardiothorac Vasc Anesth 26(1):166-171, 2012.