The aim of this study is to evaluate how an ultrasound-guided bilateral intermediate cervical plexus block affects the surgical stress response in individuals undergoing total thyroidectomy. The primary objective is to quantify this physiological response through the analysis of specific stress and inflammatory biomarkers collected from the participants' saliva.

The clinical trial will encompass a total of 48 patients, randomized equally into two distinct cohorts of 24 participants each. The control group will undergo standard total intravenous anesthesia (TIVA), whereas the experimental group will receive the bilateral intermediate cervical plexus block in combination with the TIVA protocol.

It is hypothesized that integrating this regional nerve block with total intravenous anesthesia will significantly attenuate the surgical stress response, evidenced by a reduction in salivary biomarker concentration, compared to utilizing TIVA alone during thyroid surgery.

Validating this hypothesis would offer robust scientific evidence to advocate for the routine integration of the bilateral intermediate cervical plexus block into standard anesthetic practices for total thyroidectomy. Ultimately, this approach aims to minimize perioperative stress and facilitate a more rapid postoperative recovery for patients.