A Study to Evaluate the Efficacy of Dexamethasone as an Adjuvant in Ultrasound-Guided Bilateral Superficial Cervical Plexus Block using 0.25% Bupivacaine in Patients Undergoing Thyroid Surgeries under Entropy-Guided General Anesthesia.

Abstract

Context: Ultrasound-guided bilateral superficial cervical plexus block (BSCPB) is a technique described for thyroid surgeries for postoperative analgesia as the surgery can cause severe pain and discomfort. Perineural dexamethasone is known to prolong analgesic duration and reduce postoperative nausea/vomiting.

Aims: To assess the efficacy of dexamethasone as an adjuvant to BSCPB with 0.25% bupivacaine on isoflurane consumption, intraoperative hemodynamic parameters, and postoperative analgesia in patients undergoing thyroid surgeries under general anesthesia.

Settings and design: This was a randomized control trial.

Subjects and methods: Eighty patients were randomized to two equal groups using random number table into Group A with BSCPB receiving 20 mL of 0.25% bupivacaine and Group B with BSCPB receiving 19 mL of 0.25% bupivacaine + injection dexamethasone 4 mg in the preinduction period. Hemodynamic parameters, isoflurane consumption, postoperative visual analog scale (VAS) score, and antiemetic effect over 24 h were compared between two groups.

Statistical analysis used: Microsoft excel data sheet, Chi-square test, and independent t-test were used for statistical analysis.

Results: The intraoperative hemodynamic parameters were comparable between the two groups. There was a significant difference in mean VAS score between two groups from 6 h to 20 h postoperatively. The time of rescue analgesic in Group A was 7.09 ± 1.04 min and Group was 13.19 ± 1.46 min with P < 0.0001. In Group A, 40% had nausea and 35% had vomiting, and in Group B, 7.5% had nausea and 5% had vomiting.

Conclusions: Preinduction ultrasound-guided BSCPB with bupivacaine and dexamethasone provides longer duration of postoperative analgesia and lesser nausea and vomiting compared to bupivacaine alone.