Analgesic Efficacy of Bilateral Superficial Cervical Plexus Block Using Levobupivacaine vs Ropivacaine for Thyroid Surgery Under General Anesthesia.

Background Thyroidectomy is commonly associated with moderate postoperative pain, which may delay recovery and discharge. Bilateral superficial cervical plexus block (BSCPB) is an established component of multimodal analgesia for thyroid surgery. Levobupivacaine and ropivacaine are long-acting aminoamide local anesthetics with improved safety over bupivacaine, but comparative data on their efficacy for BSCPB in thyroidectomy remain limited. Aim This study aimed to compare, in a real-world government teaching hospital cohort, the postoperative analgesic efficacy and duration of analgesia of 0.25% levobupivacaine vs 0.25% ropivacaine when used for landmark-guided BSCPB in patients undergoing thyroid surgery under general anesthesia, an institution-specific comparison for which local, technique-specific comparative data were previously unavailable. Materials and methods This prospective, observational, comparative study was conducted in the Department of Anesthesiology, Government Medical College and Hospital, Chengalpattu. Sixty American Society of Anesthesiologists I-II patients aged 20-55 years scheduled for elective thyroidectomy under general anesthesia were enrolled into two groups (n = 30 each): Group L received a total of 12 mL of 0.25% levobupivacaine (6 mL per side), and Group R received a total of 12 mL of 0.25% ropivacaine (6 mL per side) for landmark-guided BSCPB after induction. The primary outcome was the duration of analgesia (time from block to first rescue analgesic at a Visual Analog Scale (VAS) ≥4). Secondary outcomes included postoperative VAS scores at one, four, eight, 12, 16, 20, and 24 hours; the number of rescue analgesic doses in 24 hours; hemodynamic profile; and adverse events. Results Demographic and baseline variables were comparable between the groups. The duration of analgesia was significantly longer in Group L than in Group R (549.3 ± 36.3 vs 370.0 ± 59.8 minutes; p < 0.001). Postoperative VAS scores at 4, 8, 12, 16, 20, and 24 hours were significantly lower in Group L (p ≤ 0.007). A smaller proportion of patients in Group L required rescue analgesia compared with Group R (40% vs 80%; p = 0.002), and total 24-hour paracetamol consumption was significantly lower in Group L. Both groups remained hemodynamically stable, and no serious block-related complications (defined as hematoma requiring intervention, phrenic nerve palsy with respiratory compromise, or features of local anesthetic systemic toxicity) were observed. Non-serious, self-limiting events (postoperative nausea and vomiting and mild sore throat) occurred at low and comparable rates in both groups. Conclusions In this comparative observational study, BSCPB with 0.25% levobupivacaine provided a significantly longer duration of analgesia and lower postoperative VAS pain scores than 0.25% ropivacaine in thyroid surgery, indicating superior analgesic efficacy as measured by these validated, prespecified outcome measures, with reduced rescue analgesic requirements and a similar safety profile. Levobupivacaine is preferable to ropivacaine for BSCPB in thyroidectomy under general anesthesia.