en Clinical Medicine Clinical Medicine مقاله پژوهشی Original Research Article <p style="text-align: justify;"><span style="font-family:Times New Roman;"><span style="font-size:16px;"><strong><span style="color:#ffffff;"><span style="background-color:#16a085;">Background and Objective:</span></span> </strong>Pain is one of the most common complications after thyroidectomy. Opioid administration can overcome this complication, however, it has some side effects, including nausea and vomiting. So, the use of local anesthetic instead of opioids is a good alternative. This study was conducted to evaluate and compare the effect of ultrasound-guided superficial cervical plexus block (SCPB) versus anatomic landmark (LM)-based SCPB on post-operative severity of pain after thyroidectomy.<br> <strong><span style="color:#ffffff;"><span style="background-color:#16a085;">Materials and Methods:</span></span> </strong>In this clinical trial 113 patients were selected through convenience sampling method. Patients were randomly divided in to three groups: a) control, b) LM-based nerve block, and c) ultrasound-guided nerve block. Data collection was performed by demographic checklist and visual analogue scale (VAS). After general anesthesia, nerve block was performed by 15 mL of 0.25% Bupivacaine solution. Postoperative pain was measured in post anesthesia care unit (PACU) at 3, 6, 9, 12 and 24 hours. One-way analysis of variance (ANOVA), chi-square and fisher exact tests and repeated measurements were used for data analysis (SPSS V.18 software).<br> <span style="color:#ffffff;"><strong><span style="background-color:#16a085;">Results:</span></strong></span> Patients of group c in comparison to other groups received lower analgesic dose during operation (p&le;0.001); fewer of them needed post-operative analgesia (p&le;0.001). The ultrasound-guided SCPB group had significantly lower pain severity in comparison to other groups in different time intervals (p&le;0.001).<br> <span style="color:#ffffff;"><strong><span style="background-color:#16a085;">Conclusion:</span></strong></span> Ultrasound-guided superficial cervical plexus block reduced the pain after thyroidectomy. However, the ultrasound-guided nerve block is a well-organized and expanding technique, but it needs more practice and training.</span></span></p> Superficial cervical plexus block, Thyroidectomy, Pain intensity, Landmark (LM), Ultrasound 346 351 http://journal.zums.ac.ir/browse.php?a_code=A-10-5643-1&slc_lang=en&sid=1 Morteza Hashemian mortezahashemian@kmu.ac.ir 5200319475328460088902 5200319475328460088902 No Dept. of Anesthesiology and Pain Medicine, Kerman University of Medical Sciences, Kerman, Iran Amirhossein Mirafzal a.mirafzal@yahoo.com 5200319475328460088903 5200319475328460088903 No Dept. of Emergency Medicine, Kerman University of Medical Sciences, Kerman, Iran Mehrdad Noroozi mehrdadnoroozi@gmail.com 5200319475328460088904 5200319475328460088904 No Dept. of Anesthesiology, Isfahan University of Medical Sciences, Isfahan, Iran Majid Kazemi Dr.kazemi.n@rums.ac.ir 5200319475328460088905 5200319475328460088905 No School of Nursing and Midwifery, Rafsanjan University of Medical Sciences, Rafsanjan, Iran Sadra Samadi Samadi_sadra@yahoo.com 5200319475328460088906 5200319475328460088906 Yes Dept. of Anesthesiology and Pain Medicine, Kerman University of Medical Sciences, Kerman, Iran