Effect of ultrasound-guided superficial cervical plexus block combined with esketamine on postoperative recovery quality and pain in patients undergoing radical thyroidectomy for thyroid cancer

Objective This study investigated the effects of ultrasound-guided superficial cervical plexus block (SCPB) combined with esketamine (ESK) anesthesia on postoperative recovery quality, sedation, and analgesia in patients undergoing radical thyroidectomy for thyroid cancer. Methods Ninety-four patients scheduled for radical thyroidectomy were randomly divided into two study groups: the ultrasound-guided SCPB group and the ultrasound-guided SCPB combined with ESK group (SCPB/ESK group), with 47 cases in each group. Peripheral blood was collected preoperatively and 24 h postoperatively to measure hs-CRP, IL-6, IL-1β, norepinephrine, cortisol, and angiotensin II. Sedation and analgesic effects were assessed using the Ramsay Sedation Scale and Visual Analog Scale (VAS), respectively. The primary endpoint, the QOR-40 total score at 48 h postoperatively, was significantly higher in the SCPB/ESK group than in the SCPB group (mean difference: 10.0, 95% CI 3.3 to 16.7; P = 0.004). Contrast-enhanced ultrasound perfusion patterns were quantitatively analyzed by plotting time–intensity curves and calculating peak intensity (PI), time–intensity curve area under the curve (AUC), and time to peak (TTP) in the residual surgical-bed tissue. Results Compared with the SCPB group, the SCPB/ESK group showed significant reductions in intraoperative propofol consumption, intraoperative remifentanil consumption, postoperative patient-controlled intravenous analgesia (PCIA) demand doses, and post-anesthesia care unit (PACU) stay duration ( P < 0.05). Serum levels of hs-CRP, IL-6, IL-1β, NE, Cor, and Ang II at 24 h postoperatively were significantly lower in the SCPB/ESK group than in the SCPB group ( P < 0.05). VAS scores at rest and during activity gradually decreased from 6 to 24 h postoperatively in both groups and were significantly lower in the SCPB/ESK group ( P < 0.05). Ramsay scores also decreased over time and were lower in the SCPB/ESK group ( P < 0.05). Postoperative Ramsay scores differed between groups over time; because lower Ramsay scores indicate lighter sedation, these findings were interpreted descriptively rather than as unequivocal improvement in sedation quality. Compared with the SCPB group, the SCPB/ESK group had significantly higher subscale scores for emotional state, physical comfort, pain perception, psychological support, self-care ability, and total QOR-40 score at 48 h postoperatively ( P < 0.05). Meanwhile, the incidence of nausea/vomiting and extubation coughing in the SCPB/ESK group were significantly lower than those in the SCPB group ( P < 0.05). There were no statistically significant differences between the two groups in postoperative contrast-enhanced ultrasound parameters, including marginal zone PI, AUC, and TTP ( P > 0.05). Conclusion Ultrasound-guided SCPB combined with ESK in radical thyroidectomy can improve analgesia and recovery quality, attenuate inflammatory and stress responses, and reduce the incidence of nausea/vomiting and extubation coughing, and without an observed increase in the other recorded short-term adverse reactions; however, the study was not powered to exclude uncommon complications.