ORIGINAL ISSN: 2005-162X J Korean Thyroid Assoc 2012 November 5(2): 138-142 ARTICLE http://dx.doi.org/10.11106/jkta.2012.5.2.138 Usefulness of the Harmonic Scalpel in Thyroid Surgery Hwan Choe, Kwang-Yoon Jung, Soon-Young Kwon, Jeong-Soo Woo, Min Woo Park and Seung-Kuk Baek Department of Otolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea Background and Objectives: The harmonic scalpel using the ultrasonic energy is able to grasp and divide tissue while sealing small vessels in narrow operating fields. The aim of the present study was to evaluate the usefulness of the harmonic scalpel in thyroid surgery. Materials and Methods: This study was performed for 247 patients who underwent thyroidectomy. According to the use of harmonic Scalpel, the patients could be divided into two groups: the conventional technique (CT) group of knot tying and the harmonic scalpel (HS) group. Results: For hemithyroidectomy, operation time and hospital stay were shorter in the HS group compared with the CT group (p＜0.05). For total thyroidectomy with central neck dissection (CND), operation time, total drainage volume, drain removal date, and hospital stay were significantly reduced in the HS group (p＜0.05). Among the patients who underwent total thyroidectomy with CND with the HS, one patient (2.9%) showed transient recurrent laryngeal nerve palsy. Transient hypoparathyroidism showed significantly lower incidence in the HS group (p＜0.05). Conclusion: HS might be cost-effective by reducing operation time and hospital stay without increased postoperative complications. Key Words: Thyroidectomy, Harmonic scalpel The ultrasonically activated scalpel (harmonic scalpel) Introduction that uses high frequency mechanical energy makes it possible to cut and coagulate tissues and vessels The standardized thyroid surgery developed by simultaneously, without the need of knot tying.4) Theodor Kocher and Theodor Billroth, the pioneers of Therefore, this device might be useful to reduce thyroid surgery, has not undergone a major change operation time and hypoparathyroidism since in thyroid in operative technique in the last century.1) Even if surgery that requires a large amount of knot tying and alternative surgical methods in thyroid gland, including may impair the pedicle of parathyroid gland during endoscopic surgery or recurrent laryngeal nerve knot tying. stimulation, have been tried during the last decade, they The present study was conducted to evaluate the have not been widely accepted.2,3) Recently, there was strength and weakness of the harmonic scalpel by a major development in the device using ultrasonic comparing two groups that used the conventional energy and it has been using for various surgeries, technique (knot tying) and the harmonic scalpel in especially by laparoscopists. thyroid surgery. Received September 27, 2012 / Revised October 10, 2012 / Accepted October 16, 2012 Correspondence: Seung-Kuk Baek, MD, Department of Otolaryngology-Head and Neck Surgery, Korea University College of Medicine, 126-1 Anam-dong 5-ga, Seongbuk-gu, Seoul 136-705, Korea Tel: 82-2-920-5486, Fax: 82-2-925-5233, E-mail: [email protected] Copyright ⓒ 2012, the Korean Thyroid Association. All rights reserved. This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http:// creative- commons.org/licenses/by-nc/3.0/), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. 138 Usefulness of the Harmonic Scalpel in Thyroid Surgery hypoparathyroidism was classified as transient, and in Materials and Methods the other cases, it was classified as permanent. Study design Surgical technique We performed the hemithyroidectomy and total All patients had the same anesthetic and hospital thyroidectomy in 286 patients with thyroid benign and care and the patients were positioned and draped in malignant nodules, from January 2006 to June 2007. the conventional manner. About 5 cm incision was Among them, thirty-nine patients who were asso- made over the level of the thyroid isthmus. After ciated with toxic goiter and who underwent complete elevation of subplastysmal flaps, the strap muscles thyroidectomy or total thyroidectomy with lateral neck were separated in the midline and laterally reflected. dissection were excluded. Thus, a total of 247 patients The superior and inferior thyroid vessels were then were included in the study population. Institutional divided either with the harmonic scalpel with the ethical board approval and preoperative informed CS-14C handpiece (Harmonic Synergy Curved consent from all patients were obtained. All patients Blade, Ethicon Endosurgery Inc., Cincinnati, OH, USA) were explained in the price and functions of harmonic or with conventional knot tying and electric cauteri- scalpel and then harmonic scalpel was used only in zation. The only small vessels in the ligament of Berry patients with permission to use it. were clamped with clips in both groups. After that, the According to the use of harmonic scalpel, the wound was irrigated and closed using absorbable patients could be divided into two groups, prospec- suture material to approximate strap muscle, platysmal tively: the conventional technique (CT) group of tying layer, and subcutaneous layer. Then, the skin was and knots (hemithyroidectomy, n=100; total thyroi- sutured with non-absorbable material. dectomy, n=52) and the harmonic scalpel (HS) group The indications of hemithyroidectomy were benign (hemithyroidectomy, n=60; total thyroidectomy, n=35). nodule and single micropapillary carcinoma (1 cm and All patients were examined about age, gender, less) without nodal metastasis or extrathyroid spread. operation time, postoperative drainage (duration and In the other malignant nodule, total thyroidectomy with volume), hospital stay, and postoperative complication central neck dissection (level VI) was performed. including bleeding, recurrent laryngeal nerve palsy, Statistical analysis and hypoparathyroidism. Operation time was defined as the time between skin incision and skin closure. Hemithyroidectomy and total thyroidectomy groups Vacuum drains were placed in all patients, and were divided into two groups using either the HS or postoperative drainage was estimated every morning. conventional knot tying. All the patients who were to When the drainage volume was less than 20 mL per undergo surgery during the study period were selected 24 hours, the suction device was removed. All using simple random sampling. Each group was patients who were removed suction device were analyzed to estimate the usefulness of HS. Statistical discharged from the hospital the next day. In the analysis was performed using the independent t-test, patients who underwent total thyroidectomy, a series the Pearson χ2 test, and Fisher’s exact test to of serum calcium levels were obtained every post- compare the series. For all tests, a probability of less operative day until patients were discharged. All the than 0.05 was accepted as statistically significant. All patients with serum calcium levels of less than 2.10 statistical analyses were done with SPSS software mmol/L (reference range, 2.10-2.60 mmol/L) during version 12.0 (SPSS Inc., Chicago, IL, USA). the first 3 postoperative days were considered as having hypocalcemia and received oral calcium Results carbonate and vitamin D3 supplementation. If serum calcium levels returned to normal within 6 months, All groups were similar regarding age and sex, and 139 J Korean Thyroid Assoc Hwan Choe, et al there were no intraoperative complications. For hemi- difference according to tumor volume and malignancy thyroidectomy, there was no significant difference between the 2 groups. according to drainage volume and drain removal date In terms of postoperative complication, postoperative between the 2 groups. However, operation time (p= hemorrhage and transient recurrent laryngeal nerve 0.006) and hospital stay date (p=0.048) were shorter palsy occurred in one patient each (1%) who under- in the HS group compared with the CT group (Table 1). went hemithyroidectomy with the CT. Among the For total thyroidectomy with central neck dissection, patients who underwent total thyroidectomy with central there was no difference of drainage volume of first neck dissection (CND) with the HS, only one patient postoperative day between the 2 groups. However, (2.9%) showed transient recurrent laryngeal nerve operation time (p＜0.001), total drainage volume (p＜ palsy. The incidences of these complications were too 0.001), drain removal date (p=0.007), and hospital low to reach statistical significance, with the exception stay date (p＜0.001) were significantly different of transient hypoparathyroidism that showed significantly between them (Table 2). There was no significant Table 2. Difference between harmonic scalpel group and Table 1. Difference between harmonic scalpel group and conventional technique group according to clinical factors in conventional technique group according to clinical factors in patients who underwent total thyroidectomy with central neck patients who underwent the hemithyroidectomy dissection Hemithroidectomy Total thyroidectomy with CND Clinical factors (n=160) p Clinical factors (n=87) p HS (n=60) CT (n=100) HS (n=35) CT (n=52) Age 50.6±13.2 50.4±13.2 0.927* Age 48.1±14.2 45.3±14.2 0.371* † Gender 0.434 Gender 0.386† Female 44 80 Female 27 44 Male 16 20 Male 8 8 Operation time 85.0±27.6 98.4±30.9 0.006* Operation time 110.3±20.1 148.4±31.9 ＜0.001* Drainage volume Drainage volume POD 1st 32.0±13.9 32.2±13.6 0.974* POD 1st 39.0±10.7 35.7±28.4 0.445* Total volume 69.9±28.3 71.8±38.1 0.734* Total volume 84.3±22.1 123.7±67.5 ＜0.001* POD of 3.02±0.83 3.08±0.84 0.643* POD of 3.5±0.8 4.0±0.8 0.007* drain removal drain removal Hospital stay date 3.92±0.67 4.16±0.86 0.048* Hospital stay date 4.4±0.7 5.5±1.2 ＜0.001* CT: conventional technique, HS: harmonic scalpel, POD: CND: central neck dissection, CT: conventional technique, † postoperative day.